@article{KotakKotakBradeetal.2021, author = {Kotak, Bhavya and Kotak, Yash and Brade, Katja and Kubjatko, Tibor and Schweiger, Hans-Georg}, title = {Battery Crush Test Procedures in Standards and Regulation: Need for Augmentation and Harmonisation}, volume = {7}, pages = {63}, journal = {Batteries}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries7030063}, year = {2021}, abstract = {Battery safety is a prominent concern for the deployment of electric vehicles (EVs). The battery powering an EV contains highly energetic active materials and flammable organic electrolytes. Usually, an EV battery catches fire due to its thermal runaway, either immediately at the time of the accident or can take a while to gain enough heat to ignite the battery chemicals. There are numerous battery abuse testing standards and regulations available globally. Therefore, battery manufacturers are always in dilemma to choose the safest one. Henceforth, to find the optimal outcome of these two major issues, six standards (SAE J2464:2009, GB/T 31485-2015:2015, FreedomCAR:2006, ISO 12405-3:2014, IEC 62660-2:2010, and SAND2017-6295:2017) and two regulations (UN/ECE-R100.02:2013 and GTR 20:2018), that are followed by more than fifty countries in the world, are investigated in terms of their abuse battery testing conditions (crush test). This research proves that there is a need for (a) augmenting these standards and regulations as they do not consider real-life vehicle crash scenarios, and (b) one harmonised framework should be developed, which can be adopted worldwide. These outcomes will solve the battery manufacturers dilemma and will also increase the safety of EV consumers.}, language = {en} } @article{ObermaierRieblAlBayattietal.2021, author = {Obermaier, Christina and Riebl, Raphael and Al-Bayatti, Ali H. and Khan, Sarmadullah and Facchi, Christian}, title = {Measuring the Realtime Capability of Parallel-Discrete-Event-Simulations}, volume = {10}, pages = {636}, journal = {Electronics}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2079-9292}, doi = {https://doi.org/10.3390/electronics10060636}, year = {2021}, abstract = {Speeding up Discrete Event Simulations (DESs) is a broad research field. Promising Parallel Discrete Event Simulation (PDES) approaches with optimistic and conservative synchronisation schemes have emerged throughout the years. However, in the area of real-time simulation, PDESs are rarely considered. This is caused by the complex problem of fitting parallel executed DES models to a real-time clock. Hence, this paper gives an extensive review of existing conservative and optimistic synchronisation schemes for PDESs. It introduces a metric to compare their real-time capabilities to determine whether they can be used for soft or firm real-time simulation. Examples are given on how to apply this metric to evaluate PDESs using synthetic and real-world examples. The results of the investigation reveal that no final answer can be given if PDESs can be used for soft or firm real-time simulation as they are. However, boundary conditions were defined, which allow a use-case specific evaluation of the real-time capabilities of a certain parallel executed DES. Using this in-depth knowledge and can lead to predictability of the real-time behaviour of a simulation run.}, language = {en} } @article{AhlbergTidbladEdstroemHernandezetal.2021, author = {Ahlberg Tidblad, Annika and Edstr{\"o}m, Kristina and Hern{\´a}ndez, Guiomar and de Meatza, Iratxe and Landa-Medrano, Imanol and Jacas Biendicho, Jordi and Trilla, Llu{\´i}s and Buysse, Maarten and Ierides, Marcos and Perez Horno, Beatriz and Kotak, Yash and Schweiger, Hans-Georg and Koch, Daniel and Kotak, Bhavya}, title = {Future Material Developments for Electric Vehicle Battery Cells Answering Growing Demands from an End-User Perspective}, volume = {14}, pages = {4223}, journal = {Energies}, number = {14}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14144223}, year = {2021}, abstract = {Nowadays, batteries for electric vehicles are expected to have a high energy density, allow fast charging and maintain long cycle life, while providing affordable traction, and complying with stringent safety and environmental standards. Extensive research on novel materials at cell level is hence needed for the continuous improvement of the batteries coupled towards achieving these requirements. This article firstly delves into future developments in electric vehicles from a technology perspective, and the perspective of changing end-user demands. After these end-user needs are defined, their translation into future battery requirements is described. A detailed review of expected material developments follows, to address these dynamic and changing needs. Developments on anodes, cathodes, electrolyte and cell level will be discussed. Finally, a special section will discuss the safety aspects with these increasing end-user demands and how to overcome these issues.}, language = {en} } @article{KostetzerNeblStichetal.2020, author = {Kostetzer, Lucas and Nebl, Christoph and Stich, Michael and Bund, Andreas and Schweiger, Hans-Georg}, title = {Physics-Based Modeling and Parameter Identification for Lithium Ion Batteries Under High Current Discharge Conditions}, volume = {167}, pages = {140549}, journal = {Journal of the Electrochemical Society}, number = {14}, publisher = {IOP Publishing}, address = {Bristol}, issn = {1945-7111}, doi = {https://doi.org/10.1149/1945-7111/abc726}, year = {2020}, language = {en} } @article{LauschTaklaSchweiger2020, author = {Lausch, Jonas and Takla, Monir and Schweiger, Hans-Georg}, title = {Crush testing approach for flat-plate fibrous materials}, volume = {2020}, pages = {108333}, journal = {Composites Part B: Engineering}, number = {200}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-1069}, doi = {https://doi.org/10.1016/j.compositesb.2020.108333}, year = {2020}, language = {en} } @article{GeisbauerWoehrlKochetal.2021, author = {Geisbauer, Christian and W{\"o}hrl, Katharina and Koch, Daniel and Wilhelm, Gudrun and Schneider, Gerhard and Schweiger, Hans-Georg}, title = {Comparative Study on the Calendar Aging Behavior of Six Different Lithium-Ion Cell Chemistries in Terms of Parameter Variation}, volume = {14}, pages = {3358}, journal = {Energies}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14113358}, year = {2021}, abstract = {The degradation of lithium-ion cells is an important aspect, not only for quality management, but also for the customer of the application like, e.g., scooters or electric vehicles. During the lifetime of the system, the overall health on the battery plays a key role in its depreciation. Therefore, it is necessary to monitor the health of the battery during operation, i.e., cycle life, but also during stationary conditions, i.e., calendar aging. In this work, the degradation due to calendar aging is analyzed for six different cell chemistries in terms of capacity degradation and impedance increase and their performance are being compared. In a new proposed metric, the relative deviations between various cells with the exact identical aging history are being analyzed for their degradation effects and their differences, which stands out in comparison to similar research. The capacity loss was found to be most drastic at 60 °C and at higher storage voltages, even for titanate-oxide cells. LiNiMnCoO2 (NMC), LiNiCoAlO2 (NCA) and Li2TiO3 (LTO) cells at 60 °C showed the most drastic capacity decrease. NMC and NCA cells at 60 °C and highest storage voltage did not show any open circuit voltage, as their current interrupt mechanism triggered. The effect of aging shows no uniform impact on the changes in the capacity variance when comparing different aging conditions, with respect to the evaluated standard deviation for all cells. The focus of this work was on the calendar aging effect and may be supplemented in a second study for cyclic aging.}, language = {en} } @article{LauschTaklaSchweiger2021, author = {Lausch, Jonas and Takla, Monir and Schweiger, Hans-Georg}, title = {Crush characteristics of flat-plate discontinuous carbon composites}, volume = {147}, pages = {106431}, journal = {Composites Part A: Applied science and manufacturing}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1359-835X}, doi = {https://doi.org/10.1016/j.compositesa.2021.106431}, year = {2021}, language = {en} } @article{KotakMarchanteFernandezCanalsCasalsetal.2021, author = {Kotak, Yash and Marchante Fern{\´a}ndez, Carlos and Canals Casals, Lluc and Kotak, Bhavya and Koch, Daniel and Geisbauer, Christian and Trilla, Llu{\´i}s and G{\´o}mez-Nu{\~n}ez, Alberto and Schweiger, Hans-Georg}, title = {End of Electric Vehicle Batteries}, volume = {14}, pages = {2217}, journal = {Energies}, subtitle = {Reuse vs. Recycle}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14082217}, year = {2021}, abstract = {It is a fact that electric vehicles (EVs) are beneficial for climate protection. However, the current challenge is to decide on whether to reuse an EV battery or to recycle it after its first use. This paper theoretically investigates these areas i.e., recycle and reuse. It was found that there are several commercially used recycling processes and also some are under research to regain maximum possible materials and quantity. The concept of reusing (second life) of the battery is promising because, at the end of the first life, batteries from EVs can be used in several applications such as storing energy generated from renewable sources to support the government grid. However, the cost and life-cycle analysis (LCA) demonstrated that there are several aspects involved in battery reuse applications. Henceforth, one LCA generalised method cannot provide an optimal approach for all cases. It is important to have a detailed study on each of the battery reusing applications. Until then, it is safe to say that reusing the battery is a good option as it would give some time to recycling companies to develop cost and energy-efficient methods.}, language = {en} } @article{WoehrlGeisbauerNebletal.2021, author = {W{\"o}hrl, Katharina and Geisbauer, Christian and Nebl, Christoph and Lott, Susanne and Schweiger, Hans-Georg}, title = {Crashed Electric Vehicle Handling and Recommendations - State of the Art in Germany}, volume = {14}, pages = {1040}, journal = {Energies}, number = {4}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14041040}, year = {2021}, abstract = {In the near future, electric powered vehicles will represent a major part of the road traffic. Accordingly, there will be a natural increase of accidents involving electric vehicles. There are not many cases of such accidents yet and therefore the experience and correct handling are still partially open points for the involved parties, such as the rescue services for example. The aim of this work is to provide a complete overview of the accident handling sequence in Germany, starting with the damaged vehicle on site and moving on to the risks and challenges for the stakeholders, such as transport and recycling companies. Arising from the developed overview, a handling recommendation for yet undiscussed points is given. Especially, different extinguishing and deactivation methods are compared and discussed. Due to a lack of a common live-feed from battery data on site, other criteria have to be taken into account to assess the state of the battery. The wrecked vehicle—including the high voltage system—needs to be in a definite safe state at the handover to a towing service. Depending on the case, different options for securing the vehicle will be considered in this work.}, language = {en} } @unpublished{AntonioRufinoJuniorRivaSanseverinoGalloetal.2023, author = {Ant{\^o}nio Rufino J{\´u}nior, Carlos and Riva Sanseverino, Eleonora and Gallo, Pierluigi and Amaral, Murilo Machado and Koch, Daniel and Kotak, Yash and Diel, Sergej and Walter, Gero and Schweiger, Hans-Georg and Zanin, Hudson}, title = {A Comprehensive Review of EV Lithium-Ion Battery Degradation}, publisher = {Preprints}, address = {Basel}, doi = {https://doi.org/10.20944/preprints202306.0228.v2}, year = {2023}, abstract = {Lithium-ion batteries with improved energy densities have made understanding the Solid Electrolyte Interphase (SEI) generation mechanisms that cause mechanical, thermal, and chemical failures more complicated. SEI processes reduce battery capacity and power. Thus, a review of this area's understanding is important. It is essential to know how batteries degrade in EVs to estimate battery lifespan as it goes, predict, and minimize losses, and determine the ideal time for a replacement. Lithium-ion batteries used in EVs mainly suffer two types of degradation: calendar degradation and cycling degradation. Despite the existence of several existing works in the literature, several aspects of battery degradation remain unclear or have not been analyzed in detail. This work presents a systematic review of existing works in the literature. The results of the present investigation provide insight into the complex relationships among various factors affecting battery degradation mechanisms. Specifically, this systematic review examined the effects of time, side reactions, temperature fluctuations, high charge/discharge rates, depth of discharge, mechanical stress, thermal stress, and the voltage relationship on battery performance and longevity. The results revealed that these factors interact in complex ways to influence the degradation mechanisms of batteries. For example, high charge currents and deep discharges were found to accelerate degradation, while low temperatures and moderate discharge depths were shown to be beneficial for battery longevity. Additionally, the results showed that the relationship between cell voltage and State-of-Charge (SOC) plays a critical role in determining the rate of degradation. Overall, these findings have important implications for the design and operation of battery systems, as they highlight the need to carefully manage a range of factors to maximize battery performance and longevity. The result is an analysis of the main articles published in this field in recent years. This work aims to present new knowledge about fault detection, diagnosis, and management of lithium-ion batteries based on battery degradation concepts. The new knowledge is presented and discussed in a structured and comprehensive way.}, language = {en} } @unpublished{SongLiuChenetal.2022, author = {Song, Rui and Liu, Dai and Chen, Dave Zhenyu and Festag, Andreas and Trinitis, Carsten and Schulz, Martin and Knoll, Alois}, title = {Federated Learning via Decentralized Dataset Distillation in Resource Constrained Edge Environments}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2208.11311}, year = {2022}, abstract = {In federated learning, all networked clients contribute to the model training cooperatively. However, with model sizes increasing, even sharing the trained partial models often leads to severe communication bottlenecks in underlying networks, especially when communicated iteratively. In this paper, we introduce a federated learning framework FedD3 requiring only one-shot communication by integrating dataset distillation instances. Instead of sharing model updates in other federated learning approaches, FedD3 allows the connected clients to distill the local datasets independently, and then aggregates those decentralized distilled datasets (e.g. a few unrecognizable images) from networks for model training. Our experimental results show that FedD3 significantly outperforms other federated learning frameworks in terms of needed communication volumes, while it provides the additional benefit to be able to balance the trade-off between accuracy and communication cost, depending on usage scenario or target dataset. For instance, for training an AlexNet model on CIFAR-10 with 10 clients under non-independent and identically distributed (Non-IID) setting, FedD3 can either increase the accuracy by over 71\% with a similar communication volume, or save 98\% of communication volume, while reaching the same accuracy, compared to other one-shot federated learning approaches.}, language = {en} } @inproceedings{KnierimPrangeAltetal.2022, author = {Knierim, Pascal and Prange, Sarah and Alt, Florian and Feger, Sebastian and Schneegass, Stefan and Sasse, M. Angela and Bayerl, Dominik and Hof, Hans-Joachim}, title = {Inclusive Security by Design}, booktitle = {Mensch und Computer 2022 - Workshopband}, editor = {Marky, Karola and Gr{\"u}nefeld, Uwe and Kosch, Thomas}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, address = {Bonn}, doi = {https://doi.org/10.18420/muc2022-mci-ws14-128}, year = {2022}, language = {en} } @inproceedings{BayerlHutzelmannHof2025, author = {Bayerl, Dominik and Hutzelmann, Thomas and Hof, Hans-Joachim}, title = {Efficient Cross-Architecture Binary Function Embeddings through Knowledge Distillation}, booktitle = {Proceedings of the 11th ACM Cyber-Physical System Security Workshop}, publisher = {ACM}, address = {New York}, isbn = {979-8-4007-1413-9}, doi = {https://doi.org/10.1145/3709017.3737709}, pages = {43 -- 51}, year = {2025}, abstract = {Deep learning has recently been shown to be effective in various tasks related to static binary analysis. One important analysis task is the binary function similarity problem: Given the binary code of two functions compiled with different compilers, different settings, and different processor architectures, the goal is to decide whether the functions are semantically equivalent (i.e. "similar") or not. This problem has numerous applications for embedded systems, for example plagiarism detection, validation of compliance restrictions with usable software licenses, more efficient reverse engineering of existing binary codebases, or vulnerability scanning by detecting known vulnerable functions. In this paper, we propose a novel training scheme for the popular transformer neural network architecture to learn function embeddings directly from instruction listings. Unlike existing approaches, our solution explicitly considers the cross-architecture scenario: we propose a training method to adapt the model to different instruction set architectures (ISA) without having to train a new model from scratch, which allows the model to also be used efficiently for embedded systems, where there are a variety of different processor architectures. We show that our solution achieves a similarity classification accuracy of 89.6\% on a dataset consisting of several real-world open source software projects. Finally, we conduct extensive experiments to demonstrate the effectiveness of knowledge distillation in increasing the computational efficiency of the embedding model. We demonstrate a reduction in the number of parameters from 87M to 23M, while still maintaining a classification accuracy of 87.8\%. Our code and artifacts are available as open source.}, language = {en} } @unpublished{SongLiangXiaetal.2025, author = {Song, Rui and Liang, Chenwei and Xia, Yan and Zimmer, Walter and Cao, Hu and Caesar, Holger and Festag, Andreas and Knoll, Alois}, title = {CoDa-4DGS: Dynamic Gaussian Splatting with Context and Deformation Awareness for Autonomous Driving}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2503.06744}, year = {2025}, abstract = {Dynamic scene rendering opens new avenues in autonomous driving by enabling closed-loop simulations with photorealistic data, which is crucial for validating end-to-end algorithms. However, the complex and highly dynamic nature of traffic environments presents significant challenges in accurately rendering these scenes. In this paper, we introduce a novel 4D Gaussian Splatting (4DGS) approach, which incorporates context and temporal deformation awareness to improve dynamic scene rendering. Specifically, we employ a 2D semantic segmentation foundation model to self-supervise the 4D semantic features of Gaussians, ensuring meaningful contextual embedding. Simultaneously, we track the temporal deformation of each Gaussian across adjacent frames. By aggregating and encoding both semantic and temporal deformation features, each Gaussian is equipped with cues for potential deformation compensation within 3D space, facilitating a more precise representation of dynamic scenes. Experimental results show that our method improves 4DGS's ability to capture fine details in dynamic scene rendering for autonomous driving and outperforms other self-supervised methods in 4D reconstruction and novel view synthesis. Furthermore, CoDa-4DGS deforms semantic features with each Gaussian, enabling broader applications.}, language = {en} } @unpublished{HeinlPatapovasPilgermann2024, author = {Heinl, Patrizia and Patapovas, Andrius and Pilgermann, Michael}, title = {Towards AI-enabled Cyber Threat Assessment in the Health Sector}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2409.12765}, year = {2024}, abstract = {Cyber attacks on the healthcare industry can have tremendous consequences and the attack surface expands continuously. In order to handle the steadily rising workload, an expanding amount of analog processes in healthcare institutions is digitized. Despite regulations becoming stricter, not all existing infrastructure is sufficiently protected against cyber attacks. With an increasing number of devices and digital processes, the system and network landscape becomes more complex and harder to manage and therefore also more difficult to protect. The aim of this project is to introduce an AI-enabled platform that collects security relevant information from the outside of a health organization, analyzes it, delivers a risk score and supports decision makers in healthcare institutions to optimize investment choices for security measures. Therefore, an architecture of such a platform is designed, relevant information sources are identified, and AI methods for relevant data collection, selection, and risk scoring are explored.}, language = {en} } @inproceedings{BarbosadaSilvaLoboFernandezetal.2024, author = {Barbosa da Silva, Leonardo and Lobo, Silas and Fern{\´a}ndez, Evelio and Facchi, Christian}, title = {What Is the Right Bounding Box of a VRU Cluster in V2X Communication? How to Form a Good Shape?}, booktitle = {Vehits 2024: 10th International Conference on Vehicle Technology and Intelligent Transport Systems Proceedings}, editor = {Vinel, Alexey and Berns, Karsten and Ploeg, Jeroen and Gusikhin, Oleg}, publisher = {SciTePress}, address = {Set{\´u}bal}, isbn = {978-989-758-703-0}, doi = {https://doi.org/10.5220/0012699100003702}, pages = {144 -- 155}, year = {2024}, abstract = {Among the possible traffic members on a Vehicle-to-Everything network, the term Vulnerable Road User (VRU) is assigned e.g. to pedestrians and cyclists. The VRU Awareness Message (VAM) is used by VRUs to inform other users of their presence and ensure they are perceived in a traffic system. Since the number of VRUs in crowded areas might be very high, the over-the-air traffic might be overloaded. To reduce channel overload, VAMs offer a clustering feature in which VRUs with similar kinematics and positions can group themselves so that only one device transmits messages. The VRU Basic Service specification describes the cluster as a bounding box that must cover all its members using a geometric shape so that other vehicles in the vicinity can avoid colliding with the contained VRUs. This paper contributes to the standardization effort by introducing a data structure, the Cluster Map, for the clustering in the VRU Basic Service. Furthermore, this work is the first to suggest strategies for forming bounding box shapes. Simulation results show that each of the geometry types is useful in different situations, thus further research on the topic is advised.}, language = {en} } @unpublished{PaulaBauderPfeilschifteretal.2023, author = {Paula, Daniel and Bauder, Maximilian and Pfeilschifter, Claus and Petermeier, Franziska and Kubjatko, Tibor and B{\"o}hm, Klaus and Riener, Andreas and Schweiger, Hans-Georg}, title = {Impact of Partially Automated Driving Functions on Forensic Accident Reconstruction: A Simulator Study on Driver Reaction Behavior in the Event of a Malfunctioning System Behavior}, publisher = {Preprints}, address = {Basel}, doi = {https://doi.org/10.20944/preprints202311.0947.v1}, year = {2023}, abstract = {Partially automated driving functions (SAE Level 2) can control a vehicle's longitudinal and lateral movements. However, taking over the driving task involves automation risks that the driver must manage. In severe accidents, the driver's ability to avoid a collision must be assessed, considering their expected reaction behavior. The primary goal of this study is to generate essential data on driver reaction behavior in case of malfunctions in partially automated driving functions for use in legal affairs. A simulator study with two scenarios involving 32 subjects was conducted for this purpose. The first scenario investigated driver reactions to system limitations during cornering. The second scenario examined driver responses to phantom braking caused by the AEBS. As a result, the first scenario shows that none of the subjects could control the situation safely. Due to partial automation, we could also identify a new part of the reaction time, the hands-on time, which leads to increased steering reaction times of 1.18 to 1.74 seconds. In the second scenario, we found that 25 of the 32 subjects could not override the phantom braking by pressing the accelerator pedal, although 16 subjects were informed about the system analog to the actual vehicle manuals. Overall, the study suggests that the current legal perspective on vehicle control and the expected driver reaction behavior for accident avoidance should be reconsidered.}, language = {en} } @inproceedings{EderLoewHof2025, author = {Eder, Lukas and L{\"o}w, Jakob and Hof, Hans-Joachim}, title = {Charging Communication Sniffing and Man-in-the-Middle Attacks}, booktitle = {Proceedings of the 16th ACM International Conference on Future and Sustainable Energy Systems}, publisher = {ACM}, address = {New York}, isbn = {979-8-4007-1125-1}, doi = {ttps://doi.org/10.1145/3679240.3734648}, pages = {799 -- 804}, year = {2025}, abstract = {In recent years an increasing amount of electric vehicle fast charging stations have been built to meet the growing demand from rising electric vehicle numbers. The standard for fast charging communication in europe is ISO 15118. In theory the standard includes security controls for authentication and transport encryption. In reality difficulties with implementing those security controls as well as insecure design within the standard lead to multiple possible attack vectors compromising the confidentiality and authenticity of charging communication sessions. The goal of this research is to present different approaches towards performing sniffing and man-in-the-middle attacks against charging communication. We also provide a novel approach, which does not rely on race conditions and thus is more reliable than previous approaches.}, language = {en} } @inproceedings{SongFestagJagtapetal.2024, author = {Song, Rui and Festag, Andreas and Jagtap, Abhishek Dinkar and Bialdyga, Maximilian and Yan, Zhiran and Otte, Maximilian and Sadashivaiah, Sanath Tiptur and Knoll, Alois}, title = {First Mile: An Open Innovation Lab for Infrastructure-Assisted Cooperative Intelligent Transportation Systems}, booktitle = {2024 IEEE Intelligent Vehicles Symposium (IV)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3503-4881-1}, doi = {https://doi.org/10.1109/IV55156.2024.10588500}, pages = {1635 -- 1642}, year = {2024}, language = {en} } @inproceedings{HegdeLoboFestag2022, author = {Hegde, Anupama and Lobo, Silas and Festag, Andreas}, title = {Cellular-V2X for Vulnerable Road User Protection in Cooperative ITS}, booktitle = {2022 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-6975-3}, doi = {https://doi.org/10.1109/WiMob55322.2022.9941707}, pages = {118 -- 123}, year = {2022}, language = {en} } @inproceedings{SongLiuChenetal.2023, author = {Song, Rui and Liu, Dai and Chen, Dave Zhenyu and Festag, Andreas and Trinitis, Carsten and Schulz, Martin and Knoll, Alois}, title = {Federated Learning via Decentralized Dataset Distillation in Resource-Constrained Edge Environments}, booktitle = {IJCNN 2023 Conference Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-8867-9}, doi = {https://doi.org/10.1109/IJCNN54540.2023.10191879}, year = {2023}, language = {en} } @inproceedings{LoboFestagFacchi2023, author = {Lobo, Silas and Festag, Andreas and Facchi, Christian}, title = {Enhancing the Safety of Vulnerable Road Users: Messaging Protocols for V2X Communication}, booktitle = {2022 IEEE 96th Vehicular Technology Conference (VTC2022-Fall) Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-5468-1}, doi = {https://doi.org/10.1109/VTC2022-Fall57202.2022.10012775}, year = {2023}, language = {en} } @inproceedings{MayerVolkersdorferHofbaueretal.2024, author = {Mayer, Kevin and Volkersdorfer, Tina and Hofbauer, Jenny and Heinl, Patrizia and Hof, Hans-Joachim}, title = {Vehicle Security Operations Center for Cooperative, Connected and Automated Mobility}, booktitle = {SECURWARE 2024: The Eighteenth International Conference on Emerging Security Information, Systems and Technologies}, editor = {Hussain, Fatima and Fries, Steffen}, publisher = {IARIA}, address = {[s. l.]}, isbn = {978-1-68558-206-7}, url = {https://www.thinkmind.org/library/SECURWARE/SECURWARE_2024/securware_2024_2_190_30080.html}, pages = {156 -- 164}, year = {2024}, language = {en} } @inproceedings{MichlHof2024, author = {Michl, Marco and Hof, Hans-Joachim}, title = {Towards a Stakeholder-Centric Trust Management Approach for the Automotive Ecosystem}, booktitle = {SECURWARE 2024: The Eighteenth International Conference on Emerging Security Information, Systems and Technologies}, editor = {Hussain, Fatima and Fries, Steffen}, publisher = {IARIA}, address = {[s. l.]}, isbn = {978-1-68558-206-7}, url = {https://www.thinkmind.org/library/SECURWARE/SECURWARE_2024/securware_2024_2_70_30036.html}, pages = {64 -- 70}, year = {2024}, language = {en} } @inproceedings{LoewMayerHof2024, author = {L{\"o}w, Jakob and Mayer, Kevin and Hof, Hans-Joachim}, title = {Fast Charging Communication and Cybersecurity: A Technology Review}, booktitle = {SECURWARE 2024: The Eighteenth International Conference on Emerging Security Information, Systems and Technologies}, editor = {Hussain, Fatima and Fries, Steffen}, publisher = {IARIA}, address = {[s. l.]}, isbn = {978-1-68558-206-7}, url = {https://www.thinkmind.org/library/SECURWARE/SECURWARE_2024/securware_2024_2_50_30030.html}, pages = {52 -- 57}, year = {2024}, language = {en} } @inproceedings{HofbauerMayer2024, author = {Hofbauer, Jenny and Mayer, Kevin}, title = {Blue Team Fundamentals: Roles and Tools in a Security Operations Center}, booktitle = {SECURWARE 2024: The Eighteenth International Conference on Emerging Security Information, Systems and Technologies}, editor = {Hussain, Fatima and Fries, Steffen}, publisher = {IARIA}, address = {[s. l.]}, isbn = {978-1-68558-206-7}, url = {https://www.thinkmind.org/library/SECURWARE/SECURWARE_2024/securware_2024_2_220_30089.html}, pages = {176 -- 184}, year = {2024}, language = {en} } @unpublished{MorrisTatschnerHeinletal.2024, author = {Morris, John and Tatschner, Stefan and Heinl, Michael P. and Heinl, Patrizia and Newe, Thomas and Plaga, Sven}, title = {Cybersecurity as a Service}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2402.13965}, year = {2024}, language = {en} } @article{FloresFernandezSanchezMoralesBotschetal.2022, author = {Flores Fern{\´a}ndez, Alberto and S{\´a}nchez Morales, Eduardo and Botsch, Michael and Facchi, Christian and Garc{\´i}a Higuera, Andr{\´e}s}, title = {Generation of Correction Data for Autonomous Driving by Means of Machine Learning and On-Board Diagnostics}, volume = {23}, pages = {159}, journal = {Sensors}, number = {1}, publisher = {MDPI}, address = {Basel}, issn = {1424-8220}, doi = {https://doi.org/10.3390/s23010159}, year = {2022}, abstract = {A highly accurate reference vehicle state is a requisite for the evaluation and validation of Autonomous Driving (AD) and Advanced Driver Assistance Systems (ADASs). This highly accurate vehicle state is usually obtained by means of Inertial Navigation Systems (INSs) that obtain position, velocity, and Course Over Ground (COG) correction data from Satellite Navigation (SatNav). However, SatNav is not always available, as is the case of roofed places, such as parking structures, tunnels, or urban canyons. This leads to a degradation over time of the estimated vehicle state. In the present paper, a methodology is proposed that consists on the use of a Machine Learning (ML)-method (Transformer Neural Network—TNN) with the objective of generating highly accurate velocity correction data from On-Board Diagnostics (OBD) data. The TNN obtains OBD data as input and measurements from state-of-the-art reference sensors as a learning target. The results show that the TNN is able to infer the velocity over ground with a Mean Absolute Error (MAE) of 0.167 kmh (0.046 ms) when a database of 3,428,099 OBD measurements is considered. The accuracy decreases to 0.863 kmh (0.24 ms) when only 5000 OBD measurements are used. Given that the obtained accuracy closely resembles that of state-of-the-art reference sensors, it allows INSs to be provided with accurate velocity correction data. An inference time of less than 40 ms for the generation of new correction data is achieved, which suggests the possibility of online implementation. This supports a highly accurate estimation of the vehicle state for the evaluation and validation of AD and ADAS, even in SatNav-deprived environments.}, language = {en} } @article{DeloozWilleckeGarlichsetal.2022, author = {Delooz, Quentin and Willecke, Alexander and Garlichs, Keno and Hagau, Andreas-Christian and Wolf, Lars and Vinel, Alexey and Festag, Andreas}, title = {Analysis and Evaluation of Information Redundancy Mitigation for V2X Collective Perception}, volume = {10}, journal = {IEEE Access}, publisher = {IEEE}, address = {New York}, issn = {2169-3536}, doi = {https://doi.org/10.1109/ACCESS.2022.3170029}, pages = {47076 -- 47093}, year = {2022}, abstract = {Sensor data sharing enables vehicles to exchange locally perceived sensor data among each other and with the roadside infrastructure to increase their environmental awareness. It is commonly regarded as a next-generation vehicular communication service beyond the exchange of highly aggregated messages in the first generation. The approach is being considered in the European standardization process, where it relies on the exchange of locally detected objects representing anything safety-relevant, such as other vehicles or pedestrians, in periodically broadcasted messages to vehicles in direct communication range. Objects filtering methods for inclusion in a message are necessary to avoid overloading a channel and provoking unnecessary data processing. Initial studies provided in a pre-standardization report about sensor data sharing elaborated a first set of rules to filter objects based on their characteristics, such as their dynamics or type. However, these rules still lack the consideration of information received by other stations to operate. Specifically, to address the problem of information redundancy, several rules have been proposed, but their performance has not been evaluated yet comprehensively. In the present work, the rules are further analyzed, assessed, and compared. Functional and operational requirements are investigated. A performance evaluation is realized by discrete-event simulations in a scenario for a representative city with realistic vehicle densities and mobility patterns. A score and other redundancy-level metrics are elaborated to ease the evaluation and comparison of the filtering rules. Finally, improvements and future works to the filtering methods are proposed.}, language = {en} } @inproceedings{MeilingerHassSchieberetal.2023, author = {Meilinger, Florian and Haß, Jan and Schieber, Christina and Schweiger, Hans-Georg}, title = {Investigation of the hazard potential of lithium-ion cells in case of overcharging with automotive oriented high-voltage levels}, booktitle = {Applied Research Conference 2023 Conference Proceedings: 3rd July 2023 Technische Hochschule Ingolstadt}, editor = {Vaculin, Ondrej}, publisher = {Technische Hochschule Ingolstadt}, address = {Ingolstadt}, doi = {https://doi.org/10.57825/repo_in-5244}, pages = {254 -- 259}, year = {2023}, language = {en} } @inproceedings{WalterSchweiger2023, author = {Walter, Gero and Schweiger, Hans-Georg}, title = {Structural Health Monitoring of Hydrogen Pressure Vessels for Fuel Cell Electric Vehicles}, booktitle = {Applied Research Conference 2023 Conference Proceedings: 3rd July 2023 Technische Hochschule Ingolstadt}, editor = {Vaculin, Ondrej}, publisher = {Technische Hochschule Ingolstadt}, address = {Ingolstadt}, doi = {https://doi.org/10.57825/repo_in-5244}, pages = {282 -- 287}, year = {2023}, language = {en} } @inproceedings{WierlingSchweiger2023, author = {Wierling, Charlotte and Schweiger, Hans-Georg}, title = {Comparison of Facilities for Abuse Tests on Hydrogen Storage Vessels with Regard to Safety-Related Aspects}, booktitle = {Applied Research Conference 2023 Conference Proceedings: 3rd July 2023 Technische Hochschule Ingolstadt}, editor = {Vaculin, Ondrej}, publisher = {Technische Hochschule Ingolstadt}, address = {Ingolstadt}, doi = {https://doi.org/10.57825/repo_in-5244}, pages = {233 -- 238}, year = {2023}, language = {en} } @article{LoewBayerlHof2022, author = {L{\"o}w, Jakob and Bayerl, Dominik and Hof, Hans-Joachim}, title = {Implementation of a Software Based Glitching Detection Mechanism}, volume = {15}, journal = {International Journal on Advances in Security}, number = {1\&2}, publisher = {IARIA}, address = {[s. l.]}, issn = {1942-2636}, url = {https://www.iariajournals.org/security/tocv15n12.html}, pages = {31 -- 40}, year = {2022}, language = {en} } @article{MayerBayerlHof2021, author = {Mayer, Kevin and Bayerl, Dominik and Hof, Hans-Joachim}, title = {{\"U}berwachung in modernen Fahrzeugen}, volume = {45}, journal = {Datenschutz und Datensicherheit - DuD}, subtitle = {Ergebnisse einer fahrzeugforensischen Untersuchung}, number = {6}, publisher = {Springer}, address = {Berlin}, issn = {1862-2607}, doi = {https://doi.org/10.1007/s11623-021-1459-5}, pages = {399 -- 403}, year = {2021}, language = {de} } @article{BazziSepulcreDeloozetal.2024, author = {Bazzi, Alessandro and Sepulcre, Miguel and Delooz, Quentin and Festag, Andreas and Vogt, Jonas and Wieker, Horst and Berens, Friedbert and Spaanderman, Paul}, title = {Multi-Channel Operation for the Release 2 of ETSI Cooperative Intelligent Transport Systems}, volume = {8}, journal = {IEEE Communications Standards Magazine}, number = {1}, publisher = {IEEE}, address = {New York}, issn = {2471-2833}, doi = {https://doi.org/10.1109/MCOMSTD.0001.2200080}, pages = {28 -- 35}, year = {2024}, abstract = {Vehicles and road infrastructure are starting to be equipped with vehicle-to-everything (V2X) communication solutions to increase road safety and provide new services to drivers and passengers. In Europe, the deployment is based on a set of Release 1 standards developed by ETSI to support basic use cases for cooperative intelligent transport systems (C-ITS). For them, the capacity of a single 10 MHz channel in the ITS band at 5.9 GHz is considered sufficient. At the same time, the ITS stakeholders are working toward several advanced use cases, which imply a significant increment of data traffic and the need for multiple channels. To address this issue, ETSI has recently standardized a new multi-channel operation (MCO) concept for flexible, efficient, and future-proof use of multiple channels. This new concept is defined in a set of new specifications that represent the foundation for the future releases of C-ITS standards. The present article provides a comprehensive review of the new set of specifications, describing the main entities that extend the C-ITS architecture at the different layers of the protocol stack. In addition, the article provides representative examples that describe how these MCO standards will be used in the future and discusses some of the main open issues arising. The review and analysis of this article facilitate the understanding and motivation of the new set of Release 2 ETSI specifications for MCO and the identification of new research opportunities.}, language = {en} } @article{SongZhouLyuetal.2023, author = {Song, Rui and Zhou, Liguo and Lyu, Lingjuan and Festag, Andreas and Knoll, Alois}, title = {ResFed: Communication-Efficient Federated Learning With Deep Compressed Residuals}, volume = {11}, journal = {IEEE Internet of Things Journal}, number = {6}, publisher = {IEEE}, address = {New York}, issn = {2327-4662}, doi = {https://doi.org/10.1109/JIOT.2023.3324079}, pages = {9458 -- 9472}, year = {2023}, abstract = {Federated learning allows for cooperative training among distributed clients by sharing their locally learned model parameters, such as weights or gradients. However, as model size increases, the communication bandwidth required for deployment in wireless networks becomes a bottleneck. To address this, we propose a residual-based federated learning framework (ResFed) that transmits residuals instead of gradients or weights in networks. By predicting model updates at both clients and the server, residuals are calculated as the difference between updated and predicted models and contain more dense information than weights or gradients. We find that the residuals are less sensitive to an increasing compression ratio than other parameters, and hence use lossy compression techniques on residuals to improve communication efficiency for training in federated settings. With the same compression ratio, ResFed outperforms current methods (weight- or gradient-based federated learning) by over 1.4× on federated data sets, including MNIST, FashionMNIST, SVHN, CIFAR-10, CIFAR-100, and FEMNIST, in client-to-server communication, and can also be applied to reduce communication costs for server-to-client communication.}, language = {en} } @article{HegdeSongFestag2023, author = {Hegde, Anupama and Song, Rui and Festag, Andreas}, title = {Radio Resource Allocation in 5G-NR V2X: A Multi-Agent Actor-Critic Based Approach}, volume = {11}, journal = {IEEE Access}, publisher = {IEEE}, address = {New York}, issn = {2169-3536}, doi = {https://doi.org/10.1109/ACCESS.2023.3305267}, pages = {87225 -- 87244}, year = {2023}, abstract = {The efficiency of radio resource allocation and scheduling procedures in Cellular Vehicle-to-X (Cellular V2X) communication networks directly affects link quality in terms of latency and reliability. However, owing to the continuous movement of vehicles, it is impossible to have a centralized coordinating unit at all times to manage the allocation of radio resources. In the unmanaged mode of the fifth generation new radio (5G-NR) V2X, the sensing-based semi-persistent scheduling (SB-SPS) loses its effectiveness when V2X data messages become aperiodic with varying data sizes. This leads to misinformed resource allocation decisions among vehicles and frequent resource collisions. To improve resource selection, this study formulates the Cellular V2X communication network as a decentralized multi-agent networked markov decision process (MDP) where each vehicle agent executes an actor-critic-based radio resource scheduler. Developing further the actor-critic methodology for the radio resource allocation problem in Cellular V2X, two variants are derived: independent actor-critic (IAC) and shared experience actor-critic (SEAC). Results from simulation studies indicate that the actor-critic schedulers improve reliability, achieving a 15-20\% higher probability of reception under high vehicular density scenarios with aperiodic traffic patterns.}, language = {en} } @article{BauderKubjatkoSchweiger2023, author = {Bauder, Maximilian and Kubjatko, Tibor and Schweiger, Hans-Georg}, title = {Cooperative Awareness Messages' Generation Frequencies, Trigger Distributions, and Pseudonym Changes of First Commercially Deployed Vehicles in Real Operating Scenarios}, volume = {11}, journal = {IEEE Access}, publisher = {IEEE}, address = {New York}, issn = {2169-3536}, doi = {https://doi.org/10.1109/ACCESS.2023.3292576}, pages = {69708 -- 69719}, year = {2023}, abstract = {Cooperative Intelligent Transport Systems have been deployed in mass-produced vehicles in Europe (Golf 8, ID.3, etc.) since 2019, promising major improvements in vehicle safety, efficiency, and comfort. Equipped with Vehicle-to-X communication, the vehicles directly send information about their driving status to the environment. The data are already used for many Vehicle-to-X communication use-cases specified by the Car-2-Car Communication Consortium to achieve the above-mentioned improvements. This study focuses on using Vehicle-2-X communication and its messages for accident analysis. For this purpose, we investigated the advantage in temporal resolution of the continuously sent Cooperative Awareness Message compared to the Event-Data-Recorder for accident reconstruction in the pre-crash. A high resolution of the temporal accident scene is essential for the doubtless clarification of accidents. Therefore, we analyzed the generation frequencies and the trigger conditions of the Cooperative Awareness Message of vehicles available on the European market while driving in real traffic and during different parking maneuvers. Also, the pseudonym change was analyzed. We found that the average generation frequency of the Cooperative Awareness Message is higher than the 2.00 Hz recording frequency of the event data recorder for all scenarios investigated. Especially on rural roads and highways, the temporal resolution is advantageous. Since many serious accidents occur on rural roads, the use of Cooperative Awareness Messages could significantly benefit the reconstruction of the accident scene. Thus, we recommend increasing efforts to use the Cooperative Awareness Message as digital data for accident analysis and encourage more scientists to deal with this topic.}, language = {en} } @article{AntonioRufinoJuniorLimaMendesetal.2022, author = {Ant{\^o}nio Rufino J{\´u}nior, Carlos and Lima, Marcelo Ant{\^o}nio Alves and Mendes, Thais Martins and Monteiro, Henrique Luis Moreira and Ferreira, Danton Diego}, title = {Adaptive Filter Bank Based on Independent Component Analysis for Harmonic, Inter-Harmonic and Sub-Harmonic Extraction}, volume = {41}, journal = {Circuits, Systems, and Signal Processing}, number = {12}, publisher = {Birkh{\"a}user}, address = {Basel}, issn = {1531-5878}, doi = {https://doi.org/10.1007/s00034-022-02114-3}, pages = {7077 -- 7100}, year = {2022}, language = {en} } @inproceedings{DietlFacchi2025, author = {Dietl, Laura and Facchi, Christian}, title = {Is Maximum Entropy Deep Inverse Reinforcement Learning Suitable for Pedestrian Path Prediction?}, booktitle = {Proceedings of the 3rd Cognitive Mobility Conference}, editor = {Z{\"o}ldy, M{\´a}t{\´e}}, publisher = {Springer}, address = {Cham}, isbn = {978-3-031-81799-1}, doi = {https://doi.org/10.1007/978-3-031-81799-1_20}, pages = {215 -- 229}, year = {2025}, language = {en} } @inproceedings{MaksimovskiFacchi2025, author = {Maksimovski, Daniel and Facchi, Christian}, title = {Priority-Based Cooperative Driving Planner for V2X Maneuver Coordination Application}, booktitle = {2025 IEEE 22nd Consumer Communications \& Networking Conference (CCNC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3315-0805-0}, doi = {https://doi.org/10.1109/CCNC54725.2025.10975982}, year = {2025}, language = {en} } @inproceedings{LoboFestagFacchi2025, author = {Lobo, Silas and Festag, Andreas and Facchi, Christian}, title = {Adaptive Message Prioritization: How to Prioritize VRU Awareness Messages in a Congested V2X Network}, booktitle = {2024 IEEE 27th International Conference on Intelligent Transportation Systems (ITSC)}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3315-0592-9}, doi = {https://doi.org/10.1109/ITSC58415.2024.10919704}, pages = {423 -- 430}, year = {2025}, language = {en} } @inbook{DeloozMaksimovskiFestagetal.2024, author = {Delooz, Quentin and Maksimovski, Daniel and Festag, Andreas and Facchi, Christian}, title = {Design and Evaluation of V2X Communication Protocols for Cooperatively Interacting Automobiles}, booktitle = {Cooperatively Interacting Vehicles: Methods and Effects of Automated Cooperation in Traffic}, editor = {Stiller, Christoph and Althoff, Matthias and Burger, Christoph and Deml, Barbara and Eckstein, Lutz and Flemisch, Frank}, publisher = {Springer}, address = {Cham}, isbn = {978-3-031-60494-2}, doi = {https://doi.org/10.1007/978-3-031-60494-2_6}, pages = {159 -- 199}, year = {2024}, abstract = {This chapter studies two key communication services for the support of cooperative driving capabilities using Vehicle-to-Everything (V2X) communications: sensor data sharing and maneuver coordination. Based on the current state of the art in research and pre-standardization of V2X communications, we enhance the protocol design for both services and assess their performance by discrete-event simulations in highway and city scenarios. The first part of this chapter addresses the performance improvement of sensor data sharing by two complementary strategies. The shared sensor data are adapted to the available resources on the used channel. Furthermore, the redundancy of the transmitted information is reduced to lower the load on the wireless channel, whereas several approaches are proposed and assessed. The second part of the chapter analyzes cooperative maneuver coordination protocols. We propose a distributed approach based on the explicit exchange of V2X messages, which introduces priorities in maneuver coordination and studies several communication patterns for the negotiation and coordination of maneuvers among two and more vehicles. The results demonstrate the potential of V2X communications for automated driving, showcase several approaches for enhancements of sensor data sharing and maneuver coordination, and indicate the performance of these enhancements.}, language = {en} } @unpublished{SongZhouLyuetal.2022, author = {Song, Rui and Zhou, Liguo and Lyu, Lingjuan and Festag, Andreas and Knoll, Alois}, title = {ResFed: Communication Efficient Federated Learning by Transmitting Deep Compressed Residuals}, publisher = {arXiv}, address = {Ithaca}, doi = {https://doi.org/10.48550/arXiv.2212.05602}, year = {2022}, language = {en} } @inproceedings{FestagUdupaGarciaetal.2021, author = {Festag, Andreas and Udupa, Shrivatsa and Garcia, Lourdes and Wellens, Ralf and Hecht, Matthias and Ulfig, Pierre}, title = {End-to-End Performance Measurements of Drone Communications in 5G Cellular Networks}, booktitle = {2021 IEEE 94th Vehicular Technology Conference (VTC2021-Fall): Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-1368-8}, doi = {https://doi.org/10.1109/VTC2021-Fall52928.2021.9625429}, year = {2021}, language = {en} } @inproceedings{MaksimovskiFacchiFestag2024, author = {Maksimovski, Daniel and Facchi, Christian and Festag, Andreas}, title = {Packet Rate Control for Maneuver Coordination in Congested V2X Communication Environments}, booktitle = {2024 IEEE 100th Vehicular Technology Conference (VTC2024-Fall), Proceedings}, publisher = {IEEE}, address = {Piscataway}, isbn = {979-8-3315-1778-6}, doi = {https://doi.org/10.1109/VTC2024-Fall63153.2024.10758036}, year = {2024}, language = {en} } @article{AntonioRufinoJuniorRivaSanseverinoGalloetal.2022, author = {Ant{\^o}nio Rufino J{\´u}nior, Carlos and Riva Sanseverino, Eleonora and Gallo, Pierluigi and Koch, Daniel and Schweiger, Hans-Georg and Zanin, Hudson}, title = {Blockchain review for battery supply chain monitoring and battery trading}, volume = {2022}, pages = {112078}, journal = {Renewable and Sustainable Energy Reviews}, number = {157}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-0690}, doi = {https://doi.org/10.1016/j.rser.2022.112078}, year = {2022}, language = {en} } @inproceedings{FestagSong2021, author = {Festag, Andreas and Song, Rui}, title = {Analysis of Existing Approaches for Information Sharing in Cooperative Intelligent Transport Systems}, booktitle = {FISITA World Congress 2021}, subtitle = {SENSORIS and V2X Messaging}, publisher = {FISITA}, address = {Bishops Stortford}, url = {https://www.fisita.com/library/f2020-acm-012}, year = {2021}, language = {en} } @article{KochSchweiger2022, author = {Koch, Daniel and Schweiger, Hans-Georg}, title = {Possibilities for a Quick Onsite Safety-State Assessment of Stand-Alone Lithium-Ion Batteries}, volume = {8}, pages = {213}, journal = {Batteries}, number = {11}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries8110213}, year = {2022}, abstract = {Electric vehicles' high-voltage lithium-ion batteries are complex systems and can be sources of several hazards for interacting people. Sophisticated battery management systems (BMS) therefore constantly monitor their characteristics and varying states, to keep the battery within desired operational conditions and to mitigate safety risks as well as excessive degradation. However, there can be several situations where the battery is not in normal operation (e.g., a stand-alone battery) and a fully functional BMS monitoring function is not available. When necessary to interact with the system, its safety state must be deduced to ensure the safety of interactors. This can be a challenging task depending on a situation's characteristics (time pressure, technical knowledge of involved people). Thus, this article discusses how the safety state of electric vehicle batteries can be evaluated quickly even by untrained people. To develop a solution, different scenarios, which require a battery's state assessment, and the options for collecting relevant information are motivated and discussed, respectively. Finally, a mobile interface that can evaluate and display the safety state by using BMS-internal data is described and demonstrated.}, language = {en} } @article{StegerKroghMeegahapolaetal.2022, author = {Steger, Fabian and Krogh, Jonathan and Meegahapola, Lasantha and Schweiger, Hans-Georg}, title = {Calculating Available Charge and Energy of Lithium-Ion Cells Based on OCV and Internal Resistance}, volume = {15}, pages = {7902}, journal = {Energies}, number = {21}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en15217902}, year = {2022}, abstract = {The design and operation of performant and safe electric vehicles depend on precise knowledge of the behavior of their electrochemical energy storage systems. The performance of the battery management systems often relies on the discrete-time battery models, which can correctly emulate the battery characteristics. Among the available methods, electric circuit-based equations have shown to be especially useful in describing the electrical characteristics of batteries. To overcome the existing drawbacks, such as discrete-time simulations for parameter estimation and the usage of look-up tables, a set of equations has been developed in this study that solely relies on the open-circuit voltage and the internal resistance of a battery. The parameters can be obtained from typical cell datasheets or can be easily extracted via standard measurements. The proposed equations allow for the direct analytical determination of available discharge capacity and the available energy content depending on the discharge current, as well as the Peukert exponent. The fidelity of the proposed system was validated experimentally using 18650 NMC and LFP lithium-ion cells, and the results are in close agreement with the datasheet.}, language = {en} }