@inproceedings{HanzlEndisch2026, author = {Hanzl, Christian and Endisch, Christian}, title = {Closed-Form Modeling of MOSFET Switching Losses Including Variable Gate-Drain Capacitance and Zero-Voltage Switching}, booktitle = {Proceedings of the 2025 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3315-5984-7}, doi = {https://doi.org/10.1109/ITECAsia-Pacific63742.2025.11345027}, year = {2026}, language = {en} } @article{StoettnerHanzlEndisch2022, author = {St{\"o}ttner, Julia and Hanzl, Christian and Endisch, Christian}, title = {Extensive investigation of symmetrical and asymmetrical cascaded multilevel inverters for electric vehicle applications}, volume = {2022}, pages = {108009}, journal = {Electric Power Systems Research}, number = {209}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-2046}, doi = {https://doi.org/10.1016/j.epsr.2022.108009}, year = {2022}, language = {en} } @article{SchwertnerBuchbergerDiehletal.2025, author = {Schwertner, Stefan and Buchberger, Tobias and Diehl, Simon and Ferg, Rebekka and Hanzl, Christian and Hartmann, Christoph and H{\"o}lzle, Markus and Kleiner, Jan and Komsiyska, Lidiya and Lewerenz, Meinert and Liebhart, Bernhard and Schmid, Michael and Schneider, Dominik and Scholz, Florian and Speer, Sascha and St{\"o}ttner, Julia and Terbrack, Christoph and Hinterberger, Michael and Endisch, Christian}, title = {Design and Implementation of an Intelligent Reconfigurable High-Voltage Battery System for Next-Generation Electric Vehicles}, volume = {11}, pages = {11110424}, journal = {Batteries}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries11110424}, year = {2025}, abstract = {Battery system engineers face the challenge of balancing competing requirements regarding performance, maintainability, sustainability, safety, and cost—especially in the automotive industry. IBS potentially offer a solution with fewer trade-offs. They feature a battery management system with advanced sensing and data analysis capabilities that facilitate improved battery monitoring and operation. Reconfigurable energy storage units enable sophisticated operating strategies, including complete cell state control, full energy content utilization, and a measured response to faults. This article presents the design, development, and operation of a full-scale intelligent battery system prototype comprising 324 automotive lithium-ion cells with a nominal voltage of 400V. The system exhibits a modular single cell architecture and an advanced centralized battery management system. We detail the system architecture, hardware and software component design, and system integration. Initial tests demonstrate the battery's operability, extended functionality, and enhanced safety. Our analysis shows that the additional losses introduced by reconfigurability are more than offset by the benefits of full energy utilization—even for new cells, with increasing advantage as aging progresses. The results underscore the potential of intelligent battery systems and motivate further research and development toward economic assessment and industrial adoption.}, language = {en} } @article{KleinerKomsiyskaElgeretal.2019, author = {Kleiner, Jan and Komsiyska, Lidiya and Elger, Gordon and Endisch, Christian}, title = {Thermal modelling of a prismatic lithium-ion cell in a battery electric vehicle environment}, volume = {13}, pages = {62}, journal = {Energies}, subtitle = {influences of the experimental validation setup}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en13010062}, year = {2019}, abstract = {In electric vehicles with lithium-ion battery systems, the temperature of the battery cells has a great impact on performance, safety, and lifetime. Therefore, developing thermal models of lithium-ion batteries to predict and investigate the temperature development and its impact is crucial. Commonly, models are validated with experimental data to ensure correct model behaviour. However, influences of experimental setups or comprehensive validation concepts are often not considered, especially for the use case of prismatic cells in a battery electric vehicle. In this work, a 3D electro-thermal model is developed and experimentally validated to predict the cell's temperature behaviour for a single prismatic cell under battery electric vehicle (BEV) boundary conditions. One focus is on the development of a single cell's experimental setup and the investigation of the commonly neglected influences of an experimental setup on the cell's thermal behaviour. Furthermore, a detailed validation is performed for the laboratory BEV scenario for spatially resolved temperatures and heat generation. For validation, static and dynamic loads are considered as well as the detected experimental influences. The validated model is used to predict the temperature within the cell in the BEV application for constant current and Worldwide harmonized Light vehicles Test Procedure (WLTP) load profile.}, language = {en} } @article{ErikssonThomassonEkbergetal.2018, author = {Eriksson, Lars and Thomasson, Andreas and Ekberg, Kristoffer and Reig, Alberto and Eifert, Mark and Donatantonio, Fabrizio and D'Amato, Antonio and Arsie, Ivan and Pianese, Cesare and Otta, Pavel and Held, Manne and V{\"o}gele, Ulrich and Endisch, Christian}, title = {Look-ahead controls of heavy duty trucks on open roads — six benchmark solutions}, volume = {2019}, journal = {Control Engineering Practice}, number = {83}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-6939}, doi = {https://doi.org/10.1016/j.conengprac.2018.10.014}, pages = {45 -- 66}, year = {2018}, language = {en} } @article{LiebhartSatzkeKomsiyskaetal.2020, author = {Liebhart, Bernhard and Satzke, Martin and Komsiyska, Lidiya and Endisch, Christian}, title = {Application of nonlinear impedance spectroscopy for the diagnosis of lithium-ion battery cells under various operating conditions}, volume = {2020}, pages = {228673}, journal = {Journal of Power Sources}, number = {480}, publisher = {Elsevier}, address = {New York}, issn = {1873-2755}, doi = {https://doi.org/10.1016/j.jpowsour.2020.228673}, year = {2020}, language = {en} } @article{LiebhartKomsiyskaEndisch2019, author = {Liebhart, Bernhard and Komsiyska, Lidiya and Endisch, Christian}, title = {Passive impedance spectroscopy for monitoring lithium-ion battery cells during vehicle operation}, volume = {2020}, pages = {227297}, journal = {Journal of Power Sources}, number = {449}, publisher = {Elsevier}, address = {New York}, issn = {1873-2755}, doi = {https://doi.org/10.1016/j.jpowsour.2019.227297}, year = {2019}, language = {en} } @article{SchneiderVoegeleEndisch2019, author = {Schneider, Dominik and V{\"o}gele, Ulrich and Endisch, Christian}, title = {Model-based sensor data fusion of quasi-redundant voltage and current measurements in a lithium-ion battery module}, volume = {2019}, pages = {227156}, journal = {Journal of Power Sources}, number = {440}, publisher = {Elsevier}, address = {New York}, issn = {1873-2755}, doi = {https://doi.org/10.1016/j.jpowsour.2019.227156}, year = {2019}, language = {en} } @article{KleinerStuckenbergerKomsiyskaetal.2021, author = {Kleiner, Jan and Stuckenberger, Magdalena and Komsiyska, Lidiya and Endisch, Christian}, title = {Advanced monitoring and prediction of the thermal state of intelligent battery cells in electric vehicles by physics-based and data-driven modeling}, volume = {7}, pages = {31}, journal = {Batteries}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries7020031}, year = {2021}, abstract = {Novel intelligent battery systems are gaining importance with functional hardware on the cell level. Cell-level hardware allows for advanced battery state monitoring and thermal management, but also leads to additional thermal interactions. In this work, an electro-thermal framework for the modeling of these novel intelligent battery cells is provided. Thereby, a lumped thermal model, as well as a novel neural network, are implemented in the framework as thermal submodels. For the first time, a direct comparison of a physics-based and a data-driven thermal battery model is performed in the same framework. The models are compared in terms of temperature estimation with regard to accuracy. Both models are very well suited to represent the thermal behavior in novel intelligent battery cells. In terms of accuracy and computation time, however, the data-driven neural network approach with a Nonlinear AutoregRessive network with eXogeneous input (NARX) shows slight advantages. Finally, novel applications of temperature prediction in battery electric vehicles are presented and the applicability of the models is illustrated. Thereby, the conventional prediction of the state of power is extended by simultaneous temperature prediction. Additionally, temperature forecasting is used for pre-conditioning by advanced cooling system regulation to enable energy efficiency and fast charging.}, language = {en} } @article{TheilerEndischLewerenz2021, author = {Theiler, Michael and Endisch, Christian and Lewerenz, Meinert}, title = {Float Current Analysis for Fast Calendar Aging Assessment of 18650 Li(NiCoAl)O2/Graphite Cells}, volume = {7}, pages = {22}, journal = {Batteries}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries7020022}, year = {2021}, abstract = {Float currents are steady-state self-discharge currents after a transient phase—caused by anode overhang, polarization, etc.—is accomplished. The float current is measured in this study with a standard test bench for five 18650 cells (Samsung 25R) at potentiostatic conditions while the temperature is changed in 5 K steps from 5 °C to 60 °C. The entire test is performed in about 100 days resulting in 12 measurement points per cell potential for an Arrhenius representation. The float current follows the Arrhenius law with an activation energy of about 60 kJ/mol. The capacity loss measured at reference condition shows a high correlation to the results of float currents analysis. In contrast to classical calendar aging tests, the performed float current analysis enables determining the aging rate with high precision down to at least 10 °C. Returning from higher temperatures to 30 °C reference temperature shows reducing float currents at 30 °C for increasing temperature steps that may originate from an hysteresis effect that has to be investigated in future publications.}, language = {en} } @article{MayerClassenEndisch2021, author = {Mayer, Sebastian and Classen, Tobias and Endisch, Christian}, title = {Modular production control using deep reinforcement learning: proximal policy optimization}, volume = {32}, journal = {Journal of Intelligent Manufacturing}, number = {8}, publisher = {Springer Nature}, address = {Cham}, issn = {1572-8145}, doi = {https://doi.org/10.1007/s10845-021-01778-z}, pages = {2335 -- 2351}, year = {2021}, abstract = {EU regulations on CO2 limits and the trend of individualization are pushing the automotive industry towards greater flexibility and robustness in production. One approach to address these challenges is modular production, where workstations are decoupled by automated guided vehicles, requiring new control concepts. Modular production control aims at throughput-optimal coordination of products, workstations, and vehicles. For this np-hard problem, conventional control approaches lack in computing efficiency, do not find optimal solutions, or are not generalizable. In contrast, Deep Reinforcement Learning offers powerful and generalizable algorithms, able to deal with varying environments and high complexity. One of these algorithms is Proximal Policy Optimization, which is used in this article to address modular production control. Experiments in several modular production control settings demonstrate stable, reliable, optimal, and generalizable learning behavior. The agent successfully adapts its strategies with respect to the given problem configuration. We explain how to get to this learning behavior, especially focusing on the agent's action, state, and reward design.}, language = {en} } @article{MoralesTorricosBergFiggemeieretal.2025, author = {Morales Torricos, Pablo and Berg, Sascha and Figgemeier, Egbert and Endisch, Christian and Lewerenz, Meinert}, title = {The important role of lithiation-induced pressure change on apparent aging of lithium-ion batteries during accelerated cyclic aging tests}, volume = {2025}, pages = {117323}, journal = {Journal of Energy Storage}, number = {131, Part A}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2025.117323}, year = {2025}, abstract = {In assessing the lifespan of lithium-ion batteries in laboratory conditions, the measured capacity declines during accelerated cyclic aging tests but increases when the cells are left idle. This recoverable capacity loss, known in literature as apparent aging, results from an inhomogeneous lithium distribution in the anode appearing in dV/dQ and capacity difference analysis. This study explores the origin of the apparent aging by correlating lithium distribution in the anode and recoverable capacity loss, with the lithiation induced pressure change and generated electrolyte motion during cycling. To this end, we compressed five commercial pouch lithium-ion cells (NMC/Gr) with holder stiffnesses ranging from 0.9 to 15.4 MPa/mm and offset pressure from 289 to 681 kPa and subjected them to continuous cyclic aging tests. While offset pressure had no significant impact, we observed, that holder stiffnesses over 3.3 MPa/mm induces an apparent capacity loss, which is recoverable by 35 \% during a resting phase. The root cause is the so-called electrolyte motion induced salt inhomogeneity (EMSI), driven by continuous high current cycling and electrolyte motion, which is intensified by higher holder stiffness but not by offset pressure. These insights are crucial for improving the accuracy of accelerated aging tests and enhancing battery lifespan predictions.}, language = {en} } @article{YuKiranEhrensbergeretal.2025, author = {Yu, Qing and Kiran, Iqra and Ehrensberger, Moritz and Streck, Luiza and Roth, Thomas and Jossen, Andreas and Endisch, Christian and Lewerenz, Meinert}, title = {Assigning Calendar Aging during Open Circuit and Float Current Analysis to Anode and Cathode Aging Using Three-Electrode Cells}, volume = {172}, pages = {060523}, journal = {Journal of the Electrochemical Society}, number = {6}, publisher = {IOP Publishing}, address = {Bristol}, issn = {1945-7111}, doi = {https://doi.org/10.1149/1945-7111/ade295}, year = {2025}, abstract = {Analyzing calendar aging by float current analysis, instead of solely repeating capacity tests, gains more insights into aging. However, the underlying mechanisms of the recharge current required to keep the voltage constant are not yet fully understood. Therefore, this study performs float current and additional open circuit voltage (OCV) tests on 3-electrode cells for four different voltages at 30 °C. By monitoring the potentials of the anode and the cathode over time individually, the aging rate on both electrodes and the present capacity can be calculated based on adjusting the electrode-specific OCV curves according to the voltage slippery theory. The electrode-specific aging and the capacity prediction show high agreement among both methods and the capacity tests at the end of the experiment. As a result, the capacity loss appears linear-like and is associated with the loss of active lithium mainly due to SEI formation on the anode. Additionally, a significant cathode voltage decay is observed especially for higher cell voltage. According to the literature, this is associated with cathode lithiation where the conductive salt is decomposed by inserting active lithium into the cathode masking SEI losses. Finally, OCV and float current analysis return comparable results and support present 2-electrode evaluation approaches.}, language = {en} } @inproceedings{RauscherStenzelEndisch2025, author = {Rauscher, Andreas and Stenzel, Peer and Endisch, Christian}, title = {Investigation of Factors Influencing the End-of-Line Partial Discharge Testing of Electrical Machines}, booktitle = {2025 IEEE Workshop on Electrical Machines Design, Control and Diagnosis (WEMDCD)}, publisher = {IEEE}, address = {Piscataway}, doi = {https://doi.org/10.1109/WEMDCD61816.2025.11014117}, year = {2025}, language = {en} } @article{SchreiberLinSommeretal.2025, author = {Schreiber, Markus and Lin, Yilei and Sommer, Alessandro and Wassiliadis, Nikolaos and Morales Torricos, Pablo and Rogge, Marcel and Lewerenz, Meinert and Grosu, Cristina and Endisch, Christian and Jossen, Andreas and Lienkamp, Markus}, title = {Apparent vs. true battery aging: Impact of various load characteristics on accelerated aging tests}, volume = {2025}, pages = {116924}, journal = {Journal of Energy Storage}, number = {127}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2025.116924}, year = {2025}, abstract = {Vehicle applications involve highly dynamic and variable operating conditions. These result from changing driving profiles and diverse driving behaviors. To accelerate battery aging tests, experiments are often based on constant load cycles. While efficient, this approach distorts the natural degradation behavior of the cells. This study compares cell aging under real-world and laboratory load conditions. For this purpose, we compare realistic driving profiles measured in a test vehicle in the field with synthetic constant power cycles. Average discharge power and charging sequences are kept identical for comparability. Results show that constant power cycles cause stronger cell aging than dynamic loads. Differential voltage analysis indicates more lithium inventory loss and active material loss at the negative electrode under static loads. Static loading also leads to strong inhomogeneity in the negative electrode and altered charge transfer and diffusion kinetics, as shown by impedance data. After 15 months of rest, the cells recovered up to 52 of lost capacity and 66 of the resistance increase. Impedance assessment and differential voltage analysis confirm the recovery and rehomogenization of the negative electrode. These findings show that conventional accelerated tests are strongly influenced by relaxation and load dynamics. As a result, their applicability to specific use cases, such as automotive applications, is strongly limited . Therefore, andraditional test strategies require reconsideration and redesign.}, language = {en} } @article{AzzamAydinEndischetal.2025, author = {Azzam, Mohamed and Aydin, Atakhan and Endisch, Christian and Sauer, Dirk Uwe and Lewerenz, Meinert}, title = {Float Current Analysis for Lithium-Ion Battery Aging: Insights into SEI Growth and Cathode Lithiation with EIS and ICP OES}, volume = {172}, pages = {070529}, journal = {Journal of The Electrochemical Society}, number = {7}, publisher = {IOP Publishing}, address = {Bristol}, issn = {1945-7111}, doi = {https://doi.org/10.1149/1945-7111/adef85}, year = {2025}, abstract = {This study investigates calendar-aging mechanisms in lithium-ion batteries, focusing on cathode lithiation due to decomposition of conductive salt and SEI growth, by correlating quantified float currents, capacity loss rates, and pulse resistances with changes in electrochemical impedance spectroscopy (EIS) spectra. Seven SamSung 25 R cells are aged at different float voltages with periodic EIS measurements at 30 °C. Using a pre-characterization cell, the internal processes via EIS are allocated across various states of charge and temperatures and GITT measurements are performed to derive scaling factors. GITT, float currents and capacity loss rate measurements at 30 °C enables the separation of SEI growth ISEI growth and cathode lithiation current ICL based on float current behavior across a temperature range of 5 °C to 50 °C. The distribution of relaxation times (DRT) method is employed to deconvolute overlapping electrochemical processes. EIS and DRT analyses showed significant changes in cathode charge transfer resistance and diffusion, confirming that cathode lithiation correlates substantially to elevated internal resistance at high cell voltages. The theory of ISEI growth and ICL is further supported using inductively coupled plasma atomic emission spectroscopy by quantifying elemental inventory changes and linking phosphorus release and lithium consumption to degradation mechanisms.}, language = {en} } @inproceedings{GankinMayerZinnetal.2021, author = {Gankin, Dennis and Mayer, Sebastian and Zinn, Jonas and Vogel-Heuser, Birgit and Endisch, Christian}, title = {Modular Production Control with Multi-Agent Deep Q-Learning}, booktitle = {Proceedings: 2021 26th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-2989-1}, doi = {https://doi.org/10.1109/ETFA45728.2021.9613177}, year = {2021}, language = {en} } @article{SchmidKneidingerEndisch2020, author = {Schmid, Michael and Kneidinger, Hans-Georg and Endisch, Christian}, title = {Data-driven fault diagnosis in battery systems through cross-cell monitoring}, volume = {21}, journal = {IEEE Sensors Journal}, number = {2}, publisher = {IEEE}, address = {New York}, issn = {1558-1748}, doi = {https://doi.org/10.1109/JSEN.2020.3017812}, pages = {1829 -- 1837}, year = {2020}, language = {en} } @article{KleinerSinghSchmidetal.2020, author = {Kleiner, Jan and Singh, Randeep and Schmid, Michael and Komsiyska, Lidiya and Elger, Gordon and Endisch, Christian}, title = {Influence of heat pipe assisted terminal cooling on the thermal behavior of a large prismatic lithium-ion cell during fast charging in electric vehicles}, volume = {2021}, pages = {116328}, journal = {Applied Thermal Engineering}, number = {188}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1359-4311}, doi = {https://doi.org/10.1016/j.applthermaleng.2020.116328}, year = {2020}, language = {en} } @article{SchmidGebauerEndisch2021, author = {Schmid, Michael and Gebauer, Emanuel and Endisch, Christian}, title = {Structural analysis in reconfigurable battery systems for active fault diagnosis}, volume = {36}, journal = {IEEE Transactions on Power Electronics}, number = {8}, publisher = {IEEE}, address = {New York}, issn = {1941-0107}, doi = {https://doi.org/10.1109/TPEL.2021.3049573}, pages = {8672 -- 8684}, year = {2021}, language = {en} } @inbook{AltmannshoferEndisch2017, author = {Altmannshofer, Simon and Endisch, Christian}, title = {Robuste Parametersch{\"a}tzung f{\"u}r reale Anwendungen}, booktitle = {Intelligente Verfahren: Identifikation und Regelung nichtlinearer Systeme}, editor = {Schr{\"o}der, Dierk and Buss, Martin}, edition = {2., erweiterte Auflage}, publisher = {Springer Vieweg}, address = {Berlin}, isbn = {978-3-662-55327-5}, doi = {https://doi.org/10.1007/978-3-662-55327-5_12}, pages = {399 -- 472}, year = {2017}, language = {de} } @article{WiedererLeitnerEndischetal.2016, author = {Wiederer, Julian and Leitner, Lukas and Endisch, Christian and Reiss, Hans}, title = {Fast Crank-Angle Based 0D Simulation of Combustion Engine Cold Tests including Manufacturing Faults and Production Spread}, volume = {9}, journal = {SAE International Journal of Passenger Cars - Mechanical Systems}, number = {1}, publisher = {SAE International}, address = {Warrendale}, issn = {1946-4002}, doi = {https://doi.org/10.4271/2016-01-1374}, pages = {321 -- 335}, year = {2016}, language = {en} } @article{JardanStumpfVargaetal.2016, author = {J{\´a}rd{\´a}n, Rafael K. and Stumpf, P{\´e}ter and Varga, Zolt{\´a}n and Endisch, Christian and Sipos, P{\´e}ter and Simon, Mikl{\´o}s}, title = {Laboratory system for measurement of iron losses in high speed drives}, volume = {41}, journal = {International Journal of Hydrogen Energy}, number = {29}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0360-3199}, doi = {https://doi.org/10.1016/j.ijhydene.2016.01.061}, pages = {12650 -- 12658}, year = {2016}, language = {en} } @article{StolzeKaramanakosKenneletal.2014, author = {Stolze, Peter and Karamanakos, Petros and Kennel, Ralph and Manias, Stefanos and Endisch, Christian}, title = {Effective variable switching point predictive current control for ac low-voltage drives}, volume = {88}, journal = {International Journal of Control}, number = {7}, publisher = {Taylor \& Francis}, address = {London}, issn = {0020-7179}, doi = {https://doi.org/10.1080/00207179.2014.942699}, pages = {1366 -- 1378}, year = {2014}, language = {en} } @inproceedings{OkonOpferkuchEndisch2020, author = {Okon, Michael and Opferkuch, Johannes and Endisch, Christian}, title = {Modular gear transmission model for analyzing production tolerances in electric drivetrains}, booktitle = {Proceedings, 2020 IEEE International Conference on Industrial Technology}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-5754-2}, doi = {https://doi.org/10.1109/ICIT45562.2020.9067240}, pages = {709 -- 716}, year = {2020}, language = {en} } @inproceedings{GerngrossKohlerEndischetal.2020, author = {Gerngroß, Martin and Kohler, Markus and Endisch, Christian and Kennel, Ralph}, title = {Model-based control of nonlinear wire tension in dynamic needle winding processes}, booktitle = {Proceedings, 2020 IEEE International Conference on Industrial Technology}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-5754-2}, doi = {https://doi.org/10.1109/ICIT45562.2020.9067168}, pages = {381 -- 388}, year = {2020}, language = {en} } @inproceedings{KleinerKomsiyskaElgeretal.2019, author = {Kleiner, Jan and Komsiyska, Lidiya and Elger, Gordon and Endisch, Christian}, title = {Modelling of 3D temperature behavior of prismatic lithium-ion cell with focus on experimental validation under battery electric vehicle conditions}, booktitle = {2019 25th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-2078-2}, doi = {https://doi.org/10.1109/THERMINIC.2019.8923604}, year = {2019}, language = {en} } @inproceedings{SchneiderEndisch2020, author = {Schneider, Dominik and Endisch, Christian}, title = {Robustness and reliability of model-based sensor data fusion in a lithium-ion battery system}, booktitle = {IEEE CCTA 2020, 4th IEEE Conference on Control Technology and Applications}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-7140-1}, doi = {https://doi.org/10.1109/CCTA41146.2020.9206336}, pages = {685 -- 691}, year = {2020}, language = {en} } @inproceedings{SchneiderLiebhartEndisch2021, author = {Schneider, Dominik and Liebhart, Bernhard and Endisch, Christian}, title = {Adaptive Variance Estimation of Sensor Noise within a Sensor Data Fusion Framework}, booktitle = {2021 IEEE International Instrumentation and Measurement Technology Conference (I2MTC 2021) Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-9539-1}, issn = {2642-2077}, doi = {https://doi.org/10.1109/I2MTC50364.2021.9459790}, year = {2021}, language = {en} } @article{TheilerSchneiderEndisch2022, author = {Theiler, Michael and Schneider, Dominik and Endisch, Christian}, title = {Kalman Filter Tuning Using Multi-Objective Genetic Algorithm for State and Parameter Estimation of Lithium-Ion Cells}, volume = {8}, pages = {104}, journal = {Batteries}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries8090104}, year = {2022}, abstract = {To ensure a reliable and safe operation of battery systems in various applications, the system's internal states must be observed with high accuracy. Hereby, the Kalman filter is a frequently used and well-known tool to estimate the states and model parameters of a lithium-ion cell. A strong requirement is the selection of a suitable model and a reasonable initialization, otherwise the algorithm's estimation might be insufficient. Especially the process noise parametrization poses a difficult task, since it is an abstract parameter and often optimized by an arbitrary trial-and-error principle. In this work, a traceable procedure based on the genetic algorithm is introduced to determine the process noise offline considering the estimation error and filter consistency. Hereby, the parameters found are independent of the researcher's experience. Results are validated with a simulative and experimental study, using an NCA/graphite lithium-ion cell. After the transient phase, the estimation error of the state-of-charge is lower than 0.6\% and for internal resistance smaller than 4mΩ while the corresponding estimated covariances fit the error well.}, language = {en} } @inproceedings{NachtsheimHartmannEndisch2022, author = {Nachtsheim, Martin and Hartmann, Thomas and Endisch, Christian}, title = {Physically Inspired Neural Network for Modeling Induction Machine Nonlinear Magnetic Saturation}, booktitle = {ITEC+2022: 2022 IEEE/AIAA Transportation Electrification Conference and Electric Aircraft Technologies Symposium (ITEC+EATS)}, publisher = {IEEE}, address = {Piscataway (NJ)}, isbn = {978-1-6654-0560-7}, doi = {https://doi.org/10.1109/ITEC53557.2022.9813908}, pages = {874 -- 881}, year = {2022}, language = {en} } @inproceedings{KohlerFendtEndisch2022, author = {Kohler, Markus and Fendt, David and Endisch, Christian}, title = {Modeling Geometric Wire Bending Behavior in Needle Winding Processes Using Circular Arcs with Tangential Linear Functions}, booktitle = {ITEC+2022: 2022 IEEE/AIAA Transportation Electrification Conference and Electric Aircraft Technologies Symposium (ITEC+EATS)}, publisher = {IEEE}, address = {Piscataway (NJ)}, isbn = {978-1-6654-0560-7}, doi = {https://doi.org/10.1109/ITEC53557.2022.9814041}, pages = {894 -- 901}, year = {2022}, language = {en} } @inproceedings{MayerHoehmeGankinetal.2020, author = {Mayer, Sebastian and H{\"o}hme, Nikolas and Gankin, Dennis and Endisch, Christian}, title = {Adaptive Production Control in a Modular Assembly System - Towards an Agent-based Approach}, booktitle = {Proceedings, 2019 IEEE 17th International Conference on Industrial Informatics (INDIN)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-2927-3}, doi = {https://doi.org/10.1109/INDIN41052.2019.8972152}, pages = {45 -- 52}, year = {2020}, language = {en} } @inproceedings{MayerEndisch2019, author = {Mayer, Sebastian and Endisch, Christian}, title = {Adaptive production control in a modular assembly system based on partial look-ahead scheduling}, booktitle = {Proceedings, 2019 IEEE International Conference on Mechatronics (ICM)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-6959-4}, doi = {https://doi.org/10.1109/ICMECH.2019.8722904}, pages = {293 -- 300}, year = {2019}, language = {en} } @inproceedings{HerrmannStenzelVoegeleetal.2016, author = {Herrmann, Patrick and Stenzel, Peer and V{\"o}gele, Ulrich and Endisch, Christian}, title = {Optimization Algorithms for Maximizing the Slot Filling Factor of Technically Feasible Slot Geometries and Winding Layouts}, booktitle = {2016 6th International Electric Drives Production Conference (E|DPC): Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-2909-9}, doi = {https://doi.org/10.1109/EDPC.2016.7851327}, year = {2016}, language = {en} } @inproceedings{MuellerEndisch2016, author = {M{\"u}ller, Tino and Endisch, Christian}, title = {Compensation techniques for iterative rig control in multi-axial durability testing}, booktitle = {2016 IEEE 21st International Conference on Emerging Technologies and Factory Automation (ETFA)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-1314-2}, doi = {https://doi.org/10.1109/ETFA.2016.7733517}, year = {2016}, language = {en} } @inproceedings{LeitnerLagrangeEndisch2016, author = {Leitner, Lukas and Lagrange, Antoine and Endisch, Christian}, title = {End-of-line fault detection for combustion engines using one-class classification}, booktitle = {2016 IEEE International Conference on Advanced Intelligent Mechatronics (AIM)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-2065-2}, doi = {https://doi.org/10.1109/AIM.2016.7576768}, pages = {207 -- 213}, year = {2016}, language = {en} } @inproceedings{LeitnerEndisch2018, author = {Leitner, Lukas and Endisch, Christian}, title = {Skewed and Heavy-Tailed Hidden Random Walk Models with Applications in Automated Production Testing}, booktitle = {2018 IEEE 22nd International Conference on Intelligent Engineering Systems (INES)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-1122-7}, doi = {https://doi.org/10.1109/INES.2018.8523927}, pages = {000281 -- 000286}, year = {2018}, language = {en} } @inproceedings{ZiegmannSchmidEndisch2018, author = {Ziegmann, Johannes and Schmid, Michael and Endisch, Christian}, title = {Sensitivity Analysis for Driver Energy Prediction with Environmental Features and Naturalistic Data}, booktitle = {2018 IEEE International Conference on Intelligent Engineering Systems (INES)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-1122-7}, doi = {https://doi.org/10.1109/INES.2018.8523987}, pages = {000199 -- 000206}, year = {2018}, language = {en} } @inproceedings{HerrmannGerngrossEndisch2018, author = {Herrmann, Patrick and Gerngroß, Martin and Endisch, Christian}, title = {Numerical Optimization in Planning of Flexible Needle Winding Trajectories}, booktitle = {2018 IEEE International Conference on Intelligent Engineering Systems (INES)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-1122-7}, doi = {https://doi.org/10.1109/INES.2018.8523924}, pages = {000255 -- 000260}, year = {2018}, language = {en} } @inproceedings{AltmannshoferEndischTrieu2017, author = {Altmannshofer, Simon and Endisch, Christian and Trieu, Khanh Duy}, title = {On-line identification and identifiability analysis of electrical and mechanical parameters of induction machines}, booktitle = {2017 IEEE International Conference on Advanced Intelligent Mechatronics (AIM)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-6000-9}, issn = {2159-6255}, doi = {https://doi.org/10.1109/AIM.2017.8014079}, pages = {577 -- 583}, year = {2017}, language = {en} } @inproceedings{MuellerEndisch2017, author = {M{\"u}ller, Tino and Endisch, Christian}, title = {An estimation based iterative learning control approach for cross-coupled vehicle test systems}, booktitle = {2017 IEEE International Conference on Advanced Intelligent Mechatronics (AIM)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-6000-9}, issn = {2159-6255}, doi = {https://doi.org/10.1109/AIM.2017.8014210}, pages = {1375 -- 1381}, year = {2017}, language = {en} } @inproceedings{ZiegmannShiSchnoereretal.2017, author = {Ziegmann, Johannes and Shi, Jieqing and Schn{\"o}rer, Tobias and Endisch, Christian}, title = {Analysis of individual driver velocity prediction using data-driven driver models with environmental features}, booktitle = {2017 IEEE Intelligent Vehicles Symposium}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-4804-5}, doi = {https://doi.org/10.1109/IVS.2017.7995770}, pages = {517 -- 522}, year = {2017}, language = {en} } @inproceedings{VoegeleZiegmannEndisch2017, author = {V{\"o}gele, Ulrich and Ziegmann, Johannes and Endisch, Christian}, title = {Driver adaptive predictive velocity control}, booktitle = {2017 IEEE 20th International Conference on Intelligent Transportation Systems (ITSC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-1526-3}, issn = {2153-0017}, doi = {https://doi.org/10.1109/ITSC.2017.8317668}, year = {2017}, language = {en} } @inproceedings{HerrmannGerngrossEndischetal.2017, author = {Herrmann, Patrick and Gerngroß, Martin and Endisch, Christian and Stenzel, Peer and Uhlmann, Philipp}, title = {Automated contacting technology for needle winding applications with distributed windings}, booktitle = {2017 7th International Electric Drives Production Conference (EDPC) Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-1069-5}, doi = {https://doi.org/10.1109/EDPC.2017.8328169}, year = {2017}, language = {en} } @inproceedings{HerrmannGerngrossEndisch2018, author = {Herrmann, Patrick and Gerngroß, Martin and Endisch, Christian}, title = {NURBS based trajectory generation for an industrial five axis needle winding robot}, booktitle = {Conference Proceedings of 2018 4th International Conference on Control, Automation and Robotics (ICCAR)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-6338-7}, doi = {https://doi.org/10.1109/ICCAR.2018.8384640}, pages = {31 -- 36}, year = {2018}, language = {en} } @inproceedings{LeitnerEndisch2018, author = {Leitner, Lukas and Endisch, Christian}, title = {Robust stochastic process models and parameter estimation for industrial end-of-line-testing}, booktitle = {Proceedings: 2018 IEEE International Conference on Industrial Technology (ICIT)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-5949-2}, doi = {https://doi.org/10.1109/ICIT.2018.8352406}, pages = {1520 -- 1525}, year = {2018}, language = {en} } @inproceedings{LiebhartDiehlSchneideretal.2021, author = {Liebhart, Bernhard and Diehl, Simon and Schneider, Dominik and Endisch, Christian and Kennel, Ralph}, title = {Enhancing the Cell Impedance Estimation of a Lithium-Ion Battery System with Embedded Power Path Switches}, booktitle = {APEC 2021: Thirty-Sixth Annual IEEE Applied Power Electronics Conference and Exposition}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-8949-9}, issn = {2470-6647}, doi = {https://doi.org/10.1109/APEC42165.2021.9487173}, pages = {967 -- 974}, year = {2021}, language = {en} } @inproceedings{KleinerHeiderKomsiyskaetal.2021, author = {Kleiner, Jan and Heider, Alexander and Komsiyska, Lidiya and Elger, Gordon and Endisch, Christian}, title = {Experimental Study on the Thermal Interactions in Novel Intelligent Lithium-Ion Modules for Electric Vehicles}, booktitle = {Proceedings of the Twentieth InterSociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems: ITherm 2021}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-8539-2}, issn = {2694-2135}, doi = {https://doi.org/10.1109/ITherm51669.2021.9503299}, pages = {556 -- 562}, year = {2021}, language = {en} } @inproceedings{LiebhartDiehlSchmidetal.2021, author = {Liebhart, Bernhard and Diehl, Simon and Schmid, Michael and Endisch, Christian and Kennel, Ralph}, title = {Improved Impedance Measurements for Electric Vehicles with Reconfigurable Battery Systems}, booktitle = {Proceedings of the Energy Conversion Congress and Exposition - Asia, 2021 (ECCE Asia 2021)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-6344-4}, issn = {2150-6086}, doi = {https://doi.org/10.1109/ECCE-Asia49820.2021.9479060}, pages = {1736 -- 1742}, year = {2021}, language = {en} } @inproceedings{HerrmannGerngrossEndisch2019, author = {Herrmann, Patrick and Gerngroß, Martin and Endisch, Christian}, title = {Benefits of numerical optimization and CAD/CAM in needle winding processes}, booktitle = {Proceedings, 2019 IEEE International Conference on Mechatronics (ICM)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-6959-4}, doi = {https://doi.org/10.1109/ICMECH.2019.8722940}, pages = {301 -- 307}, year = {2019}, language = {en} } @inproceedings{OkonEndisch2019, author = {Okon, Michael and Endisch, Christian}, title = {On air-gap approximations for slotted electrical machine models assuming radial magnetic fields}, booktitle = {Proceedings, 2019 IEEE International Conference on Industrial Technology (ICIT)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-6376-9}, doi = {https://doi.org/10.1109/ICIT.2019.8755196}, pages = {292 -- 297}, year = {2019}, language = {en} } @inproceedings{GerngrossHerrmannEndisch2019, author = {Gerngroß, Martin and Herrmann, Patrick and Endisch, Christian}, title = {Nonlinear modelling of dynamic wire tension for needle winding processes of distributed windings}, booktitle = {Proceedings, 2019 IEEE International Conference on Industrial Technology (ICIT)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5386-6376-9}, doi = {https://doi.org/10.1109/ICIT.2019.8755052}, pages = {151 -- 156}, year = {2019}, language = {en} } @inproceedings{KohlerGerngrossEndisch2022, author = {Kohler, Markus and Gerngroß, Martin and Endisch, Christian}, title = {A Test Bench Concept and Method for Image-Based Modeling of Geometric Wire Bending Behavior in Needle Winding Processes}, booktitle = {2022 IEEE 31st International Symposium on Industrial Electronics (ISIE)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-8240-0}, issn = {2163-5145}, doi = {https://doi.org/10.1109/ISIE51582.2022.9831494}, pages = {1113 -- 1120}, year = {2022}, language = {en} } @inproceedings{NachtsheimKorkmazSchmoelzetal.2022, author = {Nachtsheim, Martin and Korkmaz, Luetfue and Schmoelz, Martin and Endisch, Christian}, title = {Observability Analysis for Parameter Identification of Induction Machines in Automotive Environment}, booktitle = {2022 IEEE 31st International Symposium on Industrial Electronics (ISIE)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-8240-0}, issn = {2163-5145}, doi = {https://doi.org/10.1109/ISIE51582.2022.9831658}, pages = {206 -- 213}, year = {2022}, language = {en} } @article{StoettnerRauscherEndisch2022, author = {St{\"o}ttner, Julia and Rauscher, Andreas and Endisch, Christian}, title = {Pareto optimization of multilevel inverter structures regarding the DC magnitude, switching frequency and switching angles}, volume = {2022}, pages = {108259}, journal = {International Journal of Electrical Power \& Energy Systems}, number = {142, Part A}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0142-0615}, doi = {https://doi.org/10.1016/j.ijepes.2022.108259}, year = {2022}, language = {en} } @article{TerbrackStoettnerEndisch2022, author = {Terbrack, Christoph and St{\"o}ttner, Julia and Endisch, Christian}, title = {Design and Validation of the Parallel Enhanced Commutation Integrated Nested Multilevel Inverter Topology}, volume = {37}, journal = {IEEE Transactions on Power Electronics}, number = {12}, publisher = {IEEE}, address = {Piscataway}, issn = {1941-0107}, doi = {https://doi.org/10.1109/TPEL.2022.3183859}, pages = {15163 -- 15174}, year = {2022}, language = {en} } @article{RauscherHufnagelEndisch2022, author = {Rauscher, Andreas and Hufnagel, Manuel and Endisch, Christian}, title = {Pareto optimization of wavelet filter design for partial discharge detection in electrical machines}, volume = {2022}, pages = {112163}, journal = {Measurement}, number = {205}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-412X}, doi = {https://doi.org/10.1016/j.measurement.2022.112163}, year = {2022}, abstract = {A reliable detection of partial discharges (PDs) in the insulation system of electrical machines is essential to prevent premature breakdowns. Wavelet filters (WFs) are often recommended for denoising this PD measurement data. However, filtering performance strongly depends on numerous settings, which impedes an optimum filter choice. We propose an approach to systematically select the best filter for denoising PD signals. First, representative PD pulses are determined from measurement data by an averaging and a singular value decomposition method. Next, realistic benchmark signals are generated for filter assessment. Further, all possible WF combinations from a set of different mother wavelet selection methods, decomposition trees, and thresholding approaches are evaluated. On the basis of two contradicting objectives, namely mean square error of noise intervals and pulse amplitude distortion, Pareto optimization is applied to choose optimal WF settings. The corresponding filters dominate several common WF proposals from previous literature.}, language = {en} } @article{KleinerLambauerSinghetal.2022, author = {Kleiner, Jan and Lambauer, Florian and Singh, Randeep and Komsiyska, Lidiya and Hinterberger, Michael and Endisch, Christian}, title = {Experimental study of cell integrated heat pipe cooling with a lithium-ion cell emulator}, volume = {2022}, pages = {105808}, journal = {Journal of Energy Storage}, number = {56, Part A}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2022.105808}, year = {2022}, language = {en} } @inproceedings{SchmidLiebhartKleineretal.2021, author = {Schmid, Michael and Liebhart, Bernhard and Kleiner, Jan and Endisch, Christian and Kennel, Ralph}, title = {Online Detection of Soft Internal Short Circuits in Lithium-Ion Battery Packs by Data-Driven Cell Voltage Monitoring}, booktitle = {Proceedings of the Energy Conversion Congress \& Exposition - Asia, 2021 (ECCE-Asia 2021)}, publisher = {IEEE}, address = {Piscataway (NJ)}, isbn = {978-1-7281-6344-4}, issn = {2150-6086}, doi = {https://doi.org/10.1109/ECCE-Asia49820.2021.9479175}, pages = {1711 -- 1718}, year = {2021}, language = {en} } @article{MoralesTorricosEndischLewerenz2023, author = {Morales Torricos, Pablo and Endisch, Christian and Lewerenz, Meinert}, title = {Apparent Aging during Accelerated Cycling Aging Test of Cylindrical Silicon Containing Li-Ion Cells}, volume = {9}, pages = {230}, journal = {Batteries}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries9040230}, year = {2023}, abstract = {Accelerated cyclic aging tests are very important for research and industry to quickly characterize lithium-ion cells. However, the accentuation of stress factors and the elimination of rest periods lead to an apparent capacity fade, that can be subsequently recovered during a resting phase. This effect is attributed to the inhomogeneous lithium distribution in the anode and is observable with differential voltage analysis (DVA). We tested cylindrical 18,650 cells with Li(NixCoyAlz)O2-graphite/silicon chemistry during two cycling and resting phases. The capacity, the pulse resistance, the DVA, and the capacity difference analysis are evaluated for cells cycled at different average SOC and current rates. An apparent capacity loss of up to 12\% was reported after 200 FCE for cells cycled under the presence of pressure gradients, while only 1\% were at low-pressure gradients. The subsequent recovery was up to 80\% of the apparent capacity loss in some cases. The impact of silicon cannot be estimated as it shows no features in the dV/dQ curves. We observe a recovery of apparent resistance increase, which is not reported for cells with pure graphite anodes. Finally, we demonstrate the strong impact of apparent aging for the lifetime prediction based on standard accelerated cyclic aging tests.}, language = {en} } @article{LechermannKleinerKomsiyskaetal.2023, author = {Lechermann, Lorenz and Kleiner, Jan and Komsiyska, Lidiya and Hinterberger, Michael and Endisch, Christian}, title = {A comparative study of data-driven electro-thermal models for reconfigurable lithium-ion batteries in real-time applications}, volume = {2023}, pages = {107188}, journal = {Journal of Energy Storage}, number = {65}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2023.107188}, year = {2023}, language = {en} } @article{TerbrackSpeerEndisch2023, author = {Terbrack, Christoph and Speer, Sascha and Endisch, Christian}, title = {Control and Implementation of the Parallel Enhanced Commutation Integrated Nested Multilevel Inverter Topology}, volume = {12}, pages = {3130}, journal = {Electronics}, number = {14}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {https://doi.org/10.3390/electronics12143130}, year = {2023}, abstract = {Due to their high efficiency and advanced battery management capability, cascaded multilevel inverters are an exciting option for battery electric powertrains. A promising, new and highly efficient cascaded multilevel inverter is the Parallel Enhanced Commutation Integrated Nested Multilevel Inverter. The inverter, with four semiconductor switches per submodule, can reconfigure individual battery cells in series and parallel and generate positive and negative phase voltages in regular four-quadrant operation. Therefore, emerging degrees of freedom in battery management and inverter operation must be managed and mapped into a specific Switching State for every switch. As controlling the high number of switches is safety-relevant, this publication profoundly explains the inverter's functionality. We introduce a Switching Function that accepts easy-to-understand functional states as input, simplifying research on higher-level control algorithms and advanced single-cell battery-management capabilities. As the Switching Function guarantees safe operation and the correct contribution of every cell to the overall functionality of the inverter, it enables researchers to confidently use and thereby accelerate research on the promising new topology. The method we describe is fast, simple, deterministic and designed to convert setpoint specifications into an executable Switching Pattern. We prove that our Switching Function is operable on an FPGA with a twenty-kilohertz setpoint update operating a 17-level inverter.}, language = {en} } @inproceedings{NachtsheimGrundEndischetal.2023, author = {Nachtsheim, Martin and Grund, Karina and Endisch, Christian and Kennel, Ralph}, title = {Online Identification of Induction Machine Parameter Deviations for Aging Detection - A Comparative Study Using Recursive Least Squares Algorithm and Extended Kalman Filter}, booktitle = {2023 IEEE Transportation Electrification Conference \& Expo (ITEC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-9742-0}, doi = {https://doi.org/10.1109/ITEC55900.2023.10186964}, year = {2023}, language = {en} } @article{AzzamEhrensbergerScheueretal.2023, author = {Azzam, Mohamed and Ehrensberger, Moritz and Scheuer, Reinhard and Endisch, Christian and Lewerenz, Meinert}, title = {Long-Term Self-Discharge Measurements and Modelling for Various Cell Types and Cell Potentials}, volume = {16}, pages = {3889}, journal = {Energies}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en16093889}, year = {2023}, abstract = {Self-discharge of lithium-ion cells leads to voltage decay over time. In this work, the self-discharge was measured at 30 °C for three cell types at various voltage levels for about 150 days in a constant voltage mode determining the current at a high precision (float current). All cells exhibit a transient part leading to a steady-state, which is no longer influenced by reversible effects. To study the effect of the check-ups on the steady-state float current, the cells, interrupted and not interrupted by check-ups, were compared. The results indicate that both the transient processes and steady-state currents are highly reproducible. In the first period of the float current, the polarization dominates the measured current, followed by the anode overhang effect dominating the process for a period of 5-30 days. After the decline of both processes, a mostly constant steady-state in the order of µA is observed. The check-up interruption generally shows no apparent effect on the reached steady-state and results only in an extended settling time. A model to simulate the transient process and steady-state of float currents was developed. The model shows a high accuracy in reproducing the results and identifying the time needed to reach the steady-state.}, language = {en} } @inproceedings{TerbrackStoettnerEndisch2020, author = {Terbrack, Christoph and St{\"o}ttner, Julia and Endisch, Christian}, title = {Operation of an externally excited synchronous machine with a hybrid multilevel inverter}, booktitle = {2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-9-0758-1536-8}, doi = {https://doi.org/10.23919/EPE20ECCEEurope43536.2020.9215895}, year = {2020}, language = {en} } @inproceedings{LiebhartDiehlEndisch2020, author = {Liebhart, Bernhard and Diehl, Simon and Endisch, Christian}, title = {Sensitivity analysis of battery cell aging estimators based on impedance spectroscopy regarding temperature compensation}, booktitle = {IEEE CCTA 2020, 4th IEEE Conference on Control Technology and Applications}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-7140-1}, doi = {https://doi.org/10.1109/CCTA41146.2020.9206395}, pages = {699 -- 705}, year = {2020}, language = {en} } @inproceedings{MuellerVoegeleEndisch2016, author = {M{\"u}ller, Tino and V{\"o}gele, Ulrich and Endisch, Christian}, title = {Disturbance compensation for iterative control of suspension durability test rigs}, booktitle = {2016 IEEE International Conference on Advanced Intelligent Mechatronics (AIM)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-2065-2}, doi = {https://doi.org/10.1109/AIM.2016.7577011}, pages = {1675 -- 1681}, year = {2016}, language = {en} } @article{MuellerZiegmannKrueneretal.2016, author = {M{\"u}ller, Tino and Ziegmann, Johannes and Kr{\"u}ner, Simon and Endisch, Christian}, title = {Optimization of inverse model identification for multi-axial test rig control}, volume = {2016}, pages = {01002}, journal = {MATEC Web of Conferences}, number = {42}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {2261-236X}, doi = {https://doi.org/10.1051/matecconf/20164201002}, year = {2016}, abstract = {Laboratory testing of multi-axial fatigue situations improves repeatability and allows a time condensing of tests which can be carried out until component failure, compared to field testing. To achieve realistic and convincing durability results, precise load data reconstruction is necessary. Cross-talk and a high number of degrees of freedom negatively affect the control accuracy. Therefore a multiple input/multiple output (MIMO) model of the system, capturing all inherent cross-couplings is identified. In a first step the model order is estimated based on the physical fundamentals of a one channel hydraulic-servo system. Subsequently, the structure of the MIMO model is optimized using correlation of the outputs, to increase control stability and reduce complexity of the parameter optimization. The identification process is successfully applied to the iterative control of a multi-axial suspension rig. The results show accurate control, with increased stability compared to control without structure optimization.}, language = {en} } @inproceedings{AltmannshoferEndischMartinetal.2016, author = {Altmannshofer, Simon and Endisch, Christian and Martin, Jan and Gerngroß, Martin and Limbacher, Reimund}, title = {Robust estimation of vehicle longitudinal dynamics parameters}, booktitle = {2016 IEEE Intelligent Vehicles Symposium (IV)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-5090-1821-5}, doi = {https://doi.org/10.1109/IVS.2016.7535443}, pages = {566 -- 571}, year = {2016}, language = {en} } @inproceedings{AltmannshoferEndisch2016, author = {Altmannshofer, Simon and Endisch, Christian}, title = {Robust Vehicle Mass and Driving Resistance Estimation}, booktitle = {2016 American Control Conference (ACC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4673-8682-1}, issn = {2378-5861}, doi = {https://doi.org/10.1109/ACC.2016.7526754}, pages = {6869 -- 6874}, year = {2016}, language = {en} } @inproceedings{AltmannshoferMartinEndisch2015, author = {Altmannshofer, Simon and Martin, Jan and Endisch, Christian}, title = {Robuste, onlinef{\"a}hige Sch{\"a}tzung von Fahrzeugmasse und Fahrwiderst{\"a}nden}, booktitle = {Autoreg 2015: auf dem Weg zum automatisierten Fahren}, publisher = {VDI Verlag}, address = {D{\"u}sseldorf}, isbn = {978-3-18-092233-1}, pages = {29 -- 36}, year = {2015}, language = {de} } @inproceedings{VoegeleEndisch2015, author = {V{\"o}gele, Ulrich and Endisch, Christian}, title = {Potential analysis of predictive optimal velocity control for electric and conventional vehicles}, booktitle = {2015 IEEE International Conference on Vehicular Electronics and Safety (ICVES)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4673-9114-6}, doi = {https://doi.org/10.1109/ICVES.2015.7396917}, pages = {196 -- 201}, year = {2015}, language = {en} } @inproceedings{MartinVoegeleEndisch2015, author = {Martin, Jan and V{\"o}gele, Ulrich and Endisch, Christian}, title = {Effects of errors in position- and navigation data on predictive vehicle operational strategy optimization}, booktitle = {2015 IEEE International Conference on Vehicular Electronics and Safety (ICVES)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4673-9114-6}, doi = {https://doi.org/10.1109/ICVES.2015.7396916}, pages = {190 -- 195}, year = {2015}, language = {en} } @inproceedings{StenzelRichnowFrankeetal.2015, author = {Stenzel, Peer and Richnow, Jan and Franke, J{\"o}rg and Endisch, Christian}, title = {Impact of the needle winding technology on the operational behavior of an asynchronous machine}, booktitle = {2015 5th International Electric Drives Production Conference (EDPC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4673-7512-2}, doi = {https://doi.org/10.1109/EDPC.2015.7323193}, year = {2015}, language = {en} } @inproceedings{JardanVargaStumpfetal.2015, author = {J{\´a}rd{\´a}n, Rafael K. and Varga, Zolt{\´a}n and Stumpf, P{\´e}ter and Nagy, Istvan and Endisch, Christian and Sipos, P{\´e}ter and Simon, Mikl{\´o}s}, title = {Development of a Dedicated Laboratory System for Measurement of Iron Losses in High Speed PMSM}, booktitle = {2015 IEEE International Conference on Industrial Technology (ICIT)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4799-7800-7}, doi = {https://doi.org/10.1109/ICIT.2015.7125181}, pages = {708 -- 713}, year = {2015}, language = {en} } @inproceedings{StenzelDollingerRichnowetal.2015, author = {Stenzel, Peer and Dollinger, P. and Richnow, Jan and Bader, T. and Franke, J{\"o}rg and Endisch, Christian}, title = {Experimental investigations of the needle winding technology regarding the influence of the wire guide geometry on the tensile wire force}, booktitle = {2015 IEEE International Conference on Industrial Technology (ICIT)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4799-7800-7}, doi = {https://doi.org/10.1109/ICIT.2015.7125487}, pages = {2642 -- 2649}, year = {2015}, language = {en} } @inproceedings{StenzelDollingerMihajlovicetal.2014, author = {Stenzel, Peer and Dollinger, P. and Mihajlovic, D. and Richnow, Jan and Franke, J{\"o}rg and Endisch, Christian}, title = {Needle winding for distributed round-wire-windings without the use of insulation disks}, booktitle = {Proceedings: 2014 4th International Electric Drives Production Conference (E|DPC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4799-5009-6}, doi = {http://doi.org/10.1109/EDPC.2014.6984387}, year = {2014}, language = {en} } @inproceedings{RichnowStenzelRenneretal.2014, author = {Richnow, Jan and Stenzel, Peer and Renner, A. and Gerling, D. and Endisch, Christian}, title = {Influence of different impregnation methods and resins on thermal behavior and lifetime of electrical stators}, booktitle = {Proceedings: 2014 4th International Electric Drives Production Conference (E|DPC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-4799-5009-6}, doi = {https://doi.org/10.1109/EDPC.2014.6984406}, year = {2014}, language = {en} } @inproceedings{NachtsheimBetzEndisch2022, author = {Nachtsheim, Martin and Betz, Michael and Endisch, Christian}, title = {Explicit analytical approach for electromagnetic modeling of arbitrary pole pair induction machines}, booktitle = {2022 12th International Conference on Power, Energy and Electrical Engineering (CPEEE)}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-6654-2049-5}, doi = {https://doi.org/10.1109/CPEEE54404.2022.9738660}, pages = {41 -- 48}, year = {2022}, language = {en} } @inproceedings{SchneiderLiebhartEndischetal.2022, author = {Schneider, Dominik and Liebhart, Bernhard and Endisch, Christian and Kennel, Ralph}, title = {Enhanced state and parameter estimation within reconfigurable battery systems for electric vehicles}, booktitle = {2022 12th International Conference on Power, Energy and Electrical Engineering (CPEEE)}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-6654-2049-5}, doi = {https://doi.org/10.1109/CPEEE54404.2022.9738700}, pages = {71 -- 77}, year = {2022}, language = {en} } @article{TheilerSchneiderEndisch2023, author = {Theiler, Michael and Schneider, Dominik and Endisch, Christian}, title = {Experimental Investigation of State and Parameter Estimation within Reconfigurable Battery Systems}, volume = {9}, pages = {145}, journal = {Batteries}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries9030145}, year = {2023}, abstract = {The battery system is one of the most-important, but also -critical components in the electric power-train. The battery's system states and parameters are commonly tracked by the battery monitoring system. However, in reality, the accuracy of the state and parameter estimation may suffer from insufficient excitation of the system. Since the current states and parameters serve as the basis for many battery management system functions, this might lead to incorrect operation and severe damage. Reconfigurable battery systems allow enhancing the system's excitation by applying a switching operation. In this contribution, the state and parameter estimation of a reconfigurable battery module were simulated and tested experimentally. Thereby, a low-exciting and a high-exciting drive cycle were compared. Furthermore, the switching patterns were applied to enhance the excitation and, hence, improve the estimation of an extended Kalman filter. The cells were switched via a pulse-width modulation signal, and the influence of frequency and duty cycle variation on the estimation accuracy were investigated. Compared to the low-excitation input, a significant improvement in the estimation of up to 46\% for the state of charge and 78\% for the internal resistance were achieved. Hereby, low frequencies and duty cycles proved to be particularly advantageous. Switching, however, has only a limited influence on an already highly excited system and may lead to additional aging due to higher heat generation.}, language = {en} } @article{NachtsheimErnstEndischetal.2023, author = {Nachtsheim, Martin and Ernst, Johannes and Endisch, Christian and Kennel, Ralph}, title = {Performance of Recursive Least Squares Algorithm Configurations for Online Parameter Identification of Induction Machines in an Automotive Environment}, volume = {9}, journal = {IEEE Transactions on Transportation Electrification}, number = {3}, publisher = {IEEE}, address = {Piscataway}, issn = {2332-7782}, doi = {https://doi.org/10.1109/TTE.2023.3244619}, pages = {4236 -- 4254}, year = {2023}, language = {en} } @inproceedings{RauscherKalamkarEndisch2024, author = {Rauscher, Andreas and Kalamkar, Siddhanth and Endisch, Christian}, title = {Impact of High Voltage Waveform on Partial Discharge Inception in Electrical Machines}, booktitle = {2024 IEEE 33rd International Symposium on Industrial Electronics (ISIE), Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-9408-5}, doi = {https://doi.org/10.1109/ISIE54533.2024.10595712}, year = {2024}, language = {en} } @article{AzzamEhrensbergerEndischetal.2024, author = {Azzam, Mohamed and Ehrensberger, Moritz and Endisch, Christian and Lewerenz, Meinert}, title = {Accelerating float current measurement with temperature ramps revealing entropy insights}, volume = {2024}, pages = {114142}, journal = {Journal of Energy Storage}, number = {102, Part B}, publisher = {Elsevier}, address = {Science}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2024.114142}, year = {2024}, language = {en} } @article{RauscherKaiserDevarajuetal.2024, author = {Rauscher, Andreas and Kaiser, Johannes and Devaraju, Manoj and Endisch, Christian}, title = {Deep learning and data augmentation for partial discharge detection in electrical machines}, volume = {133}, pages = {108074}, journal = {Engineering Applications of Artificial Intelligence}, number = {Part A}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-6769}, doi = {https://doi.org/10.1016/j.engappai.2024.108074}, year = {2024}, abstract = {Fault testing in the production line of automotive traction machines is essential to ensure the desired lifetime. Since repetitive partial discharges (PDs) caused by anomalies in the insulation system lead to premature breakdowns of electrical machines, a reliable PD detection is of great importance. This paper proposes deep learning (DL) methods to improve the discrimination of PD from background noise in comparison with the state-of-the-art amplitude based PD detection in the production line. First, a systematic data extraction and labeling procedure is introduced to obtain correctly labeled datasets from arbitrary PD measurements. In addition, datasets are enhanced with low signal-to-noise ratio PD pulses by applying a special data augmentation approach. 13 different convolutional, recurrent and fully connected neural networks are compared for various time-frequency representations of the input signals. Hyperparameters for input transform, network topology and solver are optimized for all 13 combinations to ensure a fair case study. As a result, the two-dimensional convolutional neural network with continuous wavelet transform achieves the best accuracy of around 99.76\% on a test dataset of PD signals originating from previously not utilized test objects. All DL models considered in this comparison outperform the state-of-the-art threshold-based PD classification. Even for PD events with an amplitude close to the noise level, the detection rate is still around 95\% for the best network. Furthermore, without applying the proposed data augmentation procedure, the DL models investigated are not able to distinguish small PD pulses from noise.}, language = {en} } @article{TheilerBaumannEndisch2024, author = {Theiler, Michael and Baumann, Alexander and Endisch, Christian}, title = {Influence of inhomogeneous state of charge distributions on thermal runaway propagation in lithium-ion batteries}, volume = {2024}, pages = {112483}, journal = {Journal of Energy Storage}, number = {95}, publisher = {Elsevier}, address = {Amsterdam}, doi = {https://doi.org/10.1016/j.est.2024.112483}, year = {2024}, abstract = {It is well known that lithium-ion batteries pose a certain safety risk. The thermal runaway of a cell and the subsequent thermal propagation through the battery are considered particularly dangerous. Effective solutions for their mitigation are therefore of great interest. Previous studies have shown the significant influence of a cell's state of charge (SOC) on its behavior during thermal runaway. This relation may be exploitable in a battery pack to improve its safety. This study aims to assess the leverage of active SOC reduction in the imminent threat of thermal runaway. Implementing such a technique could become feasible with the emergence of reconfigurable battery systems. Four experiments were conducted, each with a module of three fresh 63 Ah high energy pouch cells in a spring-loaded bracing. The experiments studied different stationary SOC configurations, uniform (100\% and 60\%) and non-uniform (100\%-60\%-100\% and 100\%-20\%-100\%). The results indicate that thermal propagation is substantially delay (87 s) by discharging a cell in its path. The SOC reduction primarily decreases the maximum temperature of the respective cell. Further effects are a calmer thermal runaway and prolonged propagation time within the cell as well as to the next cell. In comparison, the SOC reduction has little impact on the cell's own triggering time, as the triggering time is mainly determined by the thermal energy transferred from the preceding cell and hence by its SOC. Furthermore, the analysis of the experimental data (temperature, voltage, pressure, video) gives insights into the propagation of thermal runaway through the individual layers of a cell. With reference to the position of a cell relative to the origin of the thermal propagation, a decrease of its mass loss and an increase of its internal propagation time is observed. This effect is attributed to the decreasing module pressure due to progressive loss of material. The assessment shows that active SOC reduction techniques have great leverage for mitigating or even stopping thermal propagation in a battery pack.}, language = {en} } @article{AzzamEndischLewerenz2023, author = {Azzam, Mohamed and Endisch, Christian and Lewerenz, Meinert}, title = {Evaluating the Aging-Induced Voltage Slippery as Cause for Float Currents of Lithium-ion Cells}, volume = {10}, pages = {3}, journal = {Batteries}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries10010003}, year = {2023}, abstract = {This paper provides a comprehensive exploration of float current analysis in lithium-ion batteries, a promising new testing method to assess calendar aging. Float currents are defined as the steady-state trickle charge current after a transient part. In the literature, a correlation to capacity loss was reported. Assuming the float current compensates for the voltage decay over time and is linked to calendar aging, effects from voltage slippery must be considered. The dU/dQ analysis suggests solely a loss of active lithium. Therefore, we investigate the solid electrolyte interphase (SEI) growth as the general aging mechanism to explain the origin of float currents. Our results show that the voltage slippery theory holds true within the low to middle test voltage ranges. However, the theory's explanatory power begins to diminish at higher voltage ranges, suggesting the existence of additional, yet unidentified, factors influencing the float current. A shuttle reaction or lithiation of the cathode by electrolyte decomposition are the most promising alternative aging mechanisms at high voltages. The paper proposes a unique voltage slippery model to check for correlations between aging mechanisms, the float current test and the check-up test. For a better understanding, test strategies are proposed to verify/falsify the aging mechanisms beyond SEI.}, language = {en} } @inproceedings{RauscherStenzelEndisch2024, author = {Rauscher, Andreas and Stenzel, Peer and Endisch, Christian}, title = {Optimization of Sensor Setup and Filter Frequency for End-of-Line Partial Discharge Testing of Electrical Machines}, booktitle = {2024 IEEE International Conference on Electrical Systems for Aircraft, Railway, Ship Propulsion and Road Vehicles \& International Transportation Electrification Conference (ESARS-ITEC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-7390-5}, doi = {https://doi.org/10.1109/ESARS-ITEC60450.2024.10819886}, year = {2024}, language = {en} } @article{AzzamEhrensbergerEndischetal.2024, author = {Azzam, Mohamed and Ehrensberger, Moritz and Endisch, Christian and Sauer, Dirk Uwe and Lewerenz, Meinert}, title = {Comparison of dU/dQ, Voltage Decay, and Float Currents via Temperature Ramps and Steps in Li-ion Batteries}, volume = {8}, pages = {e202400627}, journal = {Batteries \& Supercaps}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2566-6223}, doi = {https://doi.org/10.1002/batt.202400627}, year = {2024}, language = {en} } @article{PaarmannSchreiberChahbazetal.2024, author = {Paarmann, Sabine and Schreiber, Markus and Chahbaz, Ahmed and Hildenbrand, Felix and Stahl, Gereon and Rogge, Marcel and Dechent, Philipp and Queisser, Oliver and Frankl, Sebastian Dominic and Morales Torricos, Pablo and Lu, Yao and Nikolov, Nikolay I. and Kateri, Maria and Sauer, Dirk Uwe and Danzer, Michael A. and Wetzel, Thomas and Endisch, Christian and Lienkamp, Markus and Jossen, Andreas and Lewerenz, Meinert}, title = {Short-Term Tests, Long-Term Predictions - Accelerating Ageing Characterisation of Lithium-Ion Batteries}, volume = {7}, pages = {e202300594}, journal = {Batteries \& Supercaps}, number = {11}, publisher = {Wiley}, address = {Weinheim}, issn = {2566-6223}, doi = {https://doi.org/10.1002/batt.202300594}, year = {2024}, abstract = {AbstractFor the battery industry, quick determination of the ageing behaviour of lithium-ion batteries is important both for the evaluation of existing designs as well as for R\&D on future technologies. However, the target battery lifetime is 8-10 years, which implies low ageing rates that lead to an unacceptably long ageing test duration under real operation conditions. Therefore, ageing characterisation tests need to be accelerated to obtain ageing patterns in a period ranging from a few weeks to a few months. Known strategies, such as increasing the severity of stress factors, for example, temperature, current, and taking measurements with particularly high precision, need care in application to achieve meaningful results. We observe that this challenge does not receive enough attention in typical ageing studies. Therefore, this review introduces the definition and challenge of accelerated ageing along existing methods to accelerate the characterisation of battery ageing and lifetime modelling. We systematically discuss approaches along the existing literature. In this context, several test conditions and feasible acceleration strategies are highlighted, and the underlying modelling and statistical perspective is provided. This makes the review valuable for all who set up ageing tests, interpret ageing data, or rely on ageing data to predict battery lifetime.}, language = {en} } @article{KiranAzzamEndischetal.2025, author = {Kiran, Iqra and Azzam, Mohamed and Endisch, Christian and Butt, Nauman Zafar and Lewerenz, Meinert}, title = {Evaluation of Calendar Aging in Cells with Graphite: Silicon Anode Using Float Current Analysis Under the Influence of Voltage Hysteresis}, volume = {172}, pages = {100529}, journal = {Journal of The Electrochemical Society}, number = {10}, publisher = {IOP Publishing}, address = {Bristol}, issn = {1945-7111}, doi = {https://doi.org/10.1149/1945-7111/ae0fe8}, year = {2025}, abstract = {This study investigates the calendar aging of lithium-ion batteries with graphite-silicon anodes using float current analysis. While float current analysis is already a proven method for assessing aging in cells with graphite-based anodes, the presence of silicon introduces additional complexities due to its voltage hysteresis. We address this by comparing the results for the scaling factor separately for charge and discharge. The scaling factor is initially derived from charge and discharge GITT measurements on fresh cells, including an aging-induced shift among both electrode curves. This approach enables quantification of SEI growth ISEI growth, and cathode lithiation current ICL bridging measured results for float currents with capacity loss rate. As a result, the scaling factor during charge delivered the most meaningful results regarding fitted aging currents. By extending the estimation method based on the Arrhenius equation across temperatures from 5 °C to 50 °C, our model is validated against measured float currents, improving the predictive accuracy of long-term aging trends in silicon-containing anodes. Electrochemical impedance spectroscopy provided further insights into degradation mechanisms, revealing a strong correlation between cathode lithiation by salt decomposition and resistance increase at high voltages (⩾4.15 V), confirmed by pulse tests at 100\% SOC showing a sharp resistance increase at elevated voltages.}, language = {en} } @article{KohlerMitsiosEndisch2024, author = {Kohler, Markus and Mitsios, Dionysios and Endisch, Christian}, title = {Reconstruction-based visual anomaly detection in wound rotor synchronous machine production using convolutional autoencoders and structural similarity}, volume = {2025}, journal = {Journal of Manufacturing Systems}, number = {78}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1878-6642}, doi = {https://doi.org/10.1016/j.jmsy.2024.12.005}, pages = {410 -- 432}, year = {2024}, abstract = {Manufacturing wound rotor synchronous machines (WRSMs) for electric vehicle traction systems necessitates rigorous quality inspection to ensure optimal product performance and efficiency. This paper presents a novel visual anomaly detection method for monitoring the needle winding process of WRSMs, utilizing unsupervised learning with convolutional autoencoders (CAEs) and the structural similarity index measure (SSIM). The method identifies deviations from the desired orthocyclic winding pattern during each stage of the winding process, enabling early detection of winding errors and preventing resource wastage and potential damage to the product or winding machinery. Trajectory-synchronized frame extraction aligns the visual inspection system with the winding trajectory, ensuring precise monitoring traceable to a specific point in the winding process. We present the comprehensive Winding Anomaly Dataset (WAD), which comprises images of WRSM rotor prototypes with and without winding faults recorded in different lighting conditions. The proposed reconstruction-based anomaly detection technique is trained on fault-free data only and utilizes the introduced masked mean structural dissimilarity index measure (MMSDIM) to focus on the relevant sections of the winding during inference. Comprehensive comparative analysis reveals that the CAE with unregularized latent space and the maximum mean discrepancy Wasserstein autoencoder (MMD-WAE) outperform the beta variational autoencoder (beta-VAE) in terms of anomaly detection performance, with the CAE and WAE delivering comparable results. Extensive testing confirms the approach's effectiveness, achieving 95.6 \% recall at 100 \% precision, an AUROC of 99.9 \%, and an average precision of 99.1 \% on the challenging WAD, considerably outperforming state-of-the-art visual anomaly detection models. This work thus offers a robust solution for WRSM production quality monitoring and promotes the incorporation of visual inspection in electric drive manufacturing systems.}, language = {en} } @article{SchmidVoegeleEndisch2020, author = {Schmid, Michael and V{\"o}gele, Ulrich and Endisch, Christian}, title = {A novel matrix-vector-based framework for modeling and simulation of electric vehicle battery packs}, volume = {2020}, pages = {101736}, journal = {Journal of Energy Storage}, number = {32}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2020.101736}, year = {2020}, language = {en} } @article{SchmidEndisch2022, author = {Schmid, Michael and Endisch, Christian}, title = {Online diagnosis of soft internal short circuits in series-connected battery packs using modified kernel principal component analysis}, volume = {2022}, pages = {104815}, journal = {Journal of Energy Storage}, number = {53}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2022.104815}, year = {2022}, abstract = {Safe operation of large battery storage systems requires advanced fault diagnosis that is able to detect faults and provide an early warning in the event of a fault. Since Internal Short Circuits (ISC) are the most common abuse condition leading to thermal runaway, this study addresses the early detection of incipient soft ISCs at the stage when the fault is still uncritical and does not lead to significant heat generation. The differences in cell voltages as measured by conventional battery management systems prove to be indicative features for ISC diagnosis. However, due to poor balancing and parameter variations, the cell voltage differences exhibit nonlinear variations. This work addresses this challenge with a nonlinear data model based on Kernel Principal Component Analysis (KPCA). To enable an online application in a vehicle, the present work reduces the computational complexity of the method by an optimal choice of training data. An analysis of the contribution of each cell to the fault statistics enables identification of the faulty cell. Since early-stage ISCs can exhibit a wide range of short-circuit resistances, experimental validation is performed with resistances from 10Ω to 10kΩ, which are correctly detected and isolated by the optimized cross-cell monitoring in all cases.}, language = {en} } @article{LewerenzRaheFuchsetal.2020, author = {Lewerenz, Meinert and Rahe, Christiane and Fuchs, Georg and Endisch, Christian and Sauer, Dirk Uwe}, title = {Evaluation of shallow cycling on two types of uncompressed automotive Li(Ni1/3Mn1/3Co1/3)O2-Graphite pouch cells}, volume = {2020}, pages = {101529}, journal = {Journal of Energy Storage}, number = {30}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2020.101529}, year = {2020}, language = {en} } @article{KleinerStuckenbergerKomsiyskaetal.2021, author = {Kleiner, Jan and Stuckenberger, Magdalena and Komsiyska, Lidiya and Endisch, Christian}, title = {Real-time core temperature prediction of prismatic automotive lithium-ion battery cells based on artificial neural networks}, volume = {2021}, pages = {102588}, journal = {Journal of Energy Storage}, number = {39}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2021.102588}, year = {2021}, language = {en} } @article{KleinerHeiderKomsiyskaetal.2021, author = {Kleiner, Jan and Heider, Alexander and Komsiyska, Lidiya and Elger, Gordon and Endisch, Christian}, title = {Thermal behavior of intelligent automotive lithium-ion batteries: Experimental study with switchable cells and reconfigurable modules}, volume = {2021}, pages = {103274}, journal = {Journal of Energy Storage}, number = {44, Part A}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2021.103274}, year = {2021}, language = {en} } @article{SchmidKleinerEndisch2022, author = {Schmid, Michael and Kleiner, Jan and Endisch, Christian}, title = {Early detection of Internal Short Circuits in series-connected battery packs based on nonlinear process monitoring}, volume = {2022}, pages = {103732}, journal = {Journal of Energy Storage}, number = {48}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2021.103732}, year = {2022}, language = {en} } @article{KleinerLechermannKomsiyskaetal.2021, author = {Kleiner, Jan and Lechermann, Lorenz and Komsiyska, Lidiya and Elger, Gordon and Endisch, Christian}, title = {Thermal behavior of intelligent automotive lithium-ion batteries}, volume = {2021}, pages = {102686}, journal = {Journal of energy storage}, subtitle = {operating strategies for adaptive thermal balancing by reconfiguration}, number = {40}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2021.102686}, year = {2021}, language = {en} }