@article{SchneiderLiebhartEndisch2021, author = {Schneider, Dominik and Liebhart, Bernhard and Endisch, Christian}, title = {Active state and parameter estimation as part of intelligent battery systems}, volume = {2021}, pages = {102638}, journal = {Journal of Energy Storage}, number = {39}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2021.102638}, year = {2021}, language = {en} } @inproceedings{RauscherBraunHiemeretal.2025, author = {Rauscher, Andreas and Braun, Julian and Hiemer, Rainer and Heldwein, Marcelo Lobo and Endisch, Christian}, title = {Convolutional Neural Networks and Thresholding Approaches for Single and Multi-Sensor Detection of Partial Discharges in Electrical Machine Stators}, booktitle = {Proceedings of the 15th International 2025 IEEE Symposium on Diagnostics for Electrical Machines, Power Electronics and Drives (SDEMPED)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-8820-6}, doi = {https://doi.org/10.1109/SDEMPED53223.2025.11153974}, year = {2025}, language = {en} } @article{VoegeleEndisch2016, author = {V{\"o}gele, Ulrich and Endisch, Christian}, title = {Predictive Vehicle Velocity Control Using Dynamic Traffic Information}, pages = {2016-01-0121}, journal = {SAE Technical Paper}, publisher = {SAE}, address = {Warrendale}, issn = {0148-7191}, doi = {https://doi.org/10.4271/2016-01-0121}, year = {2016}, language = {en} } @inproceedings{ZiegmannDenkVoegeleetal.2018, author = {Ziegmann, Johannes and Denk, Florian and V{\"o}gele, Ulrich and Endisch, Christian}, title = {Stochastic Driver Velocity Prediction with Environmental Features on Naturalistic Driving Data}, booktitle = {2018 IEEE Intelligent Transportation Systems Conference}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-7281-0323-5}, doi = {https://doi.org/10.1109/ITSC.2018.8569767}, pages = {1807 -- 1814}, year = {2018}, language = {en} } @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{MoralesTorricosGallenbergerDroeseetal.2025, author = {Morales Torricos, Pablo and Gallenberger, Andreas and Droese, Dominik and Kowal, Julia and Endisch, Christian and Lewerenz, Meinert}, title = {Analyzing the Impact of Electrolyte Motion Induced Salt Inhomogeneity Effect on Apparent Aging: Role of Current Rates and Temperature Effects in Accelerated Cyclic Aging Tests in Li-Ion Batteries}, volume = {9}, pages = {e202500559}, journal = {Batteries \& Supercaps}, number = {4}, publisher = {Wiley}, address = {Weinheim}, issn = {2566-6223}, doi = {https://doi.org/10.1002/batt.202500559}, year = {2025}, abstract = {Accurate and rapid assessment of lithium-ion battery lifetime is essential for predicting remaining lifespan, enabling the selection of appropriate cells for specific applications and determining suitability for second-life use. However, accelerated cyclic aging tests may underestimate a cell's total lifespan due to exaggerated capacity fade that does not occur under real-world conditions. This increased capacity fade is primarily driven by electrolyte motion induced salt inhomogeneity (EMSI) and loss of homogeneity of lithium distribution (HLD). This study investigates the impact of varying charge and discharge currents on capacity loss during accelerated testing in compressed NMC-Gr pouch cells. Most of the capacity loss observed during cycling is fully recoverable after a resting period, with some cells regaining up to 81\% of their lost capacity. Contrary to expectations, cells subjected to the highest cycling currents do not exhibit the greatest recoverable capacity loss. This phenomenon can be attributed to the interplay between current and temperature: While higher cycling currents exacerbate EMSI and HLD loss, they simultaneously elevate cell temperature, which mitigates EMSI by weakening polarization, enhancing electrolyte salt diffusion and homogenizing lithium distribution in the anode. Consequently, higher temperatures counteract HLD and EMSI-effect and therefore reduce apparent capacity loss.}, 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{TheilerNoerpelBaumannetal.2025, author = {Theiler, Michael and N{\"o}rpel, Felix and Baumann, Alexander and Endisch, Christian}, title = {Thermal fault detection in battery systems using principal component analysis with adaptive thresholding}, volume = {2026}, pages = {119101}, journal = {Journal of Energy Storage}, number = {141, Part B}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-1538}, doi = {https://doi.org/10.1016/j.est.2025.119101}, year = {2025}, abstract = {Lithium-ion cells pose serious safety risks when they enter a state with highly exothermic reactions known as thermal runaway. Because elevated temperature is the ultimate trigger for this failure mode, reliable and timely detection of abnormal cell temperature is critical. Early detection enables, user warning, fast emergency response, and provides the basis for effective active prevention strategies. In this work, we present an unsupervised data-driven approach that detects thermal faults by monitoring inter-cell voltage deviations. We apply principal component analysis (PCA) to capture systematic changes in voltage homogeneity that occur when a cell within a battery module heats abnormally. By systematically analyzing the effects of thermal stress on voltage homogeneity under varying operating conditions, we reveal requirements for a reliable detection method. Leveraging these insights, we introduce an adaptive thresholding mechanism. This novel approach significantly boosts the sensitivity to faults for a wide range of operating conditions while maintaining detection robustness. We validate the method through extensive experiments in which we externally heat a single cell within a module with the power of 1 W. Compared to both conventional linear PCA and nonlinear kernel PCA with a constant threshold, linear PCA with adaptive thresholding achieves a significantly better balance between sensitivity and robustness across the full range of test conditions.}, language = {en} } @article{AzzamSauerEndischetal.2025, author = {Azzam, Mohamed and Sauer, Dirk Uwe and Endisch, Christian and Lewerenz, Meinert}, title = {Comprehensive Analysis of Float Current Behavior and Calendar Aging Mechanisms in Lithium-Ion Batteries}, volume = {9}, pages = {e202500349}, journal = {Batteries \& Supercaps}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2566-6223}, doi = {https://doi.org/10.1002/batt.202500349}, year = {2025}, abstract = {Aiming to quantify degradation currents from solid electrolyte interphase formation (ISEIgrowth) and gain of active lithium due to cathode lithiation (ICL), resulting from electrolyte decomposition, the float current behavior of lithium-ion batteries is investigated with different cathode materials. The float current, IFloat , represents the recharge current required to maintain the cell at a fixed potential during calendar aging. This current arises as lithium is irreversibly consumed at the anode or inserted into the cathode, shifting the electrode potentials. To account for the asymmetric response of the electrodes, a voltage-dependent scaling factor, SF, is introduced, derived from the slopes of the electrode-specific voltage curves. Using this factor in combination with measured float currents and capacity loss rates from check-up tests, ISEIgrowth and ICL is quantified at 30 °C across various float voltages. Although the SF and capacity data are limited to 30 °C, the model is extended to a range of 5-50 °C using only float current measurements. The results show that using capacity loss rates alone underestimate ISEIgrowth and that ICL, contributes significantly to the observed float current at elevated voltages, indicating that cathode lithiation plays an increasingly important role in high-voltage calendar aging.}, language = {en} }