Fakultät Elektro- und Informationstechnik
Pouch cells in automotive modules age and may experience mechanical abuse while mechanically confined, yet almost all published comparisons of fresh and aged cells release the aging constraint before the abuse test. In the present work, three commercial 6 Ah pouch cells were electrochemically cycled to approximately 80% State of Health inside a spring-loaded flat-plate fixture initialized at a nominal average stack pressure of 0.11 MPaand were then indented quasi-statically at nominally 100% State of Charge without releasing the confinement. Three uncycled cells were tested as fresh references in the corresponding fixture configuration. The aging state was tracked by capacity fade and Electrochemical Impedance Spectroscopy. The aged cells built up force earlier, reaching 20 kNat 11% smaller intrusion, and the electrically detected Internal Short Circuit occurred at 18% lower displacement and at a 10% lower group-mean force, while peak force and displacement at peak remained within the observed cell-to-cell scatter. This differs from the right shift reported for many pouch-cell studies in which the aging constraint was released before testing and resembles the earlier onsets reported for hard-cased cylindrical cells. Following the electrically detected Internal Short Circuit onset, the aged-cell voltage reached 1 Vlater than that of the fresh references. The results are consistent with confinement history being a contributing and experimentally controllable variable in abuse tests on aged cells.
This study presents a novel analysis of the commutation loop inductance in reconfigurable battery systems based on a half-bridge topology. The investigation considers variations in the number of series connected battery cells before being linked of the half-bridge. Based on these findings, three methods are explored to minimize loop inductance: 1) introducing magnetically coupled conductor/auxiliary loops to create a freewheeling path for the magnetization current, with parts of the auxiliary loop formed by sections of the power loop to achieve near-ideal coupling, 2) employing a solid copper shield as an alternative to auxiliary loops, and 3) optimizing the physical arrangement of the series connected battery cells. Experimental results show a reduction in loop inductance of up to 59% using the magnetically coupled auxiliary loop, and up to 66% with the solid copper shield.
Estimating the effect of age-induced defocus on object detection performance of automotive cameras
(2025)
Defocus in automotive cameras can be caused by aging or changing temperature, and is one of the major reasons for degradation of data captured by the camera. This work investigates the effect of defocus on safety-critical object detection by comparing various pre-trained object detection models, primarily convolutional neural networks. These models are compared in their performance against static scenes with different levels of defocus. The static scene contained the three classes: person, bicycle, and cars, and the movement of the camera towards these objects was mimicked in discrete steps from 100 meter to 2 meter. During each distance step, the defocus was varied in 9 steps between +30 and −50 micrometer. To allow controlled defocusing, the general design of a state-of-the-art automotive camera was modified to allow lateral movement of the sensor in relation to the objective. All frames captured at 0 micrometer defocus were annotated for the three object classes, and these ground-truth annotations were compared to annotations from object detection models to calculate precision, recall and F1score. The results showed that the precision remained close to 1.0 in multiple models, leaving the changes in F1mainly impacted by changes in recall. Both large and small models performed well against defocus until 40 meter. At 60 meter the models performed within an acceptable range at low defocus and beyond 60 meter, recall dropped below 0.5. It was seen that at 100 meter the detection of objects was almost negligible, with the models detecting only one object or none.
Internal combustion engine vehicles and electric vehicles share many similarities in the event of a vehicle fire but also differ in certain aspects. While both vehicle types release pollutants typical of vehicle fires, fires involving electric vehicles also emit battery-specific emissions. To investigate hazardous-substance exposure of emergency responders, two fire tests were carried out on identical electric vehicles. In each test, one battery cell was mechanically short-circuited, resulting in thermal runaway and propagation within the battery. Gas and time-resolved aerosol measurements, wipe samples, extinguishing agent samples, and urine samples were analyzed. A primary finding was the pronounced variability between the two fire events: despite comparable test conditions, the two vehicle fires exhibited markedly different development patterns, highlighting the inherent variability of electric vehicle fire behavior. Wipe samples showed increased metal concentrations after the tests, with maximum post-extinguishing surface concentrations of 7.4 mg/m2 nickel, 17.45 mg/m2 cobalt, and 14.25 mg/m2 lithium. Extinguishing agent samples showed increased concentrations of inorganic contaminants and polycyclic aromatic hydrocarbons. Urine samples showed no indication of a systematic increase in creatinine-adjusted metal concentrations among protected participants. Toxic gases were released immediately after cell short-circuiting, with hydrogen fluoride, hydrogen cyanide, and acetylene reaching approximately 500 ppm before visible flames occurred. Aerosol measurements identified transiently elevated particle number concentrations in the exterior near-field environment and, in one test, inside the passenger compartment, where a shift towards smaller particle diameters was observed. The findings demonstrate multiple responder-relevant exposure pathways and substantial variability in electric vehicle fire events.
Die Technische Hochschule Ingolstadt (THI) verfügt über 20 Jahre Erfahrung mit kooperativen Promotionen. In diesem Zusammenhang wurde bereits im Jahr 2013 ein Graduiertenzentrum zur Unterstützung der Promovierenden und Betreuenden an der THI eingeführt. Im Jahr 2023 folgte der Start zweier Promotionszentren an der THI. Grundlage hierfür war das im Januar 2023 in Kraft getretene Bayerische Hochschulinnovationsgesetz (BayHIG), das die Möglichkeit zur Verleihung eines fachgebundenen und befristeten eigenständigen Promotionsrechts an bayerischen Hochschulen für angewandte Wissenschaften geschaffen hat. In einem Begutachtungsverfahren überzeugte die THI mit dem Promotionszentrum Ingenieurwissenschaften (PZ ING) und dem Promotionszentrum Künstliche Intelligenz / Informatik (PZ KI/INF) durch eine nachweisbare Forschungsstärke und die Einbettung der wissenschaftlichen Qualifizierung in eine grundständige akademische Lehre. In den Promotionszentren ING und KI/INF sind derzeit jeweils 23 forschungsstarke Professorinnen und Professoren tätig. Innerhalb der ersten zweieinhalb Jahre wurden 90 Doktorandinnen und Doktoranden in die beiden Promotionszentren der THI aufgenommen, drei von ihnen haben mittlerweile den kompletten Promotionsprozess durchlaufen und ihre Promotion erfolgreich abgeschlossen. Im Folgenden werden strukturelle und prozessuale Erfahrungen sowie vor allem Spannungsfelder und Aspekte der Qualitätssicherung in den Promotionszentren beleuchtet.
Indentation and crush tests are widely used as crash-relevant surrogates for mechanical intrusion in Lithium-Ion Batteries (LIBs), yet their interpretation still relies on macroscopic, binary pass/fail criteria established at the Beginning of Life (BoL). This neglects how calendar and cyclic degradation alter a cell’s mechanical, thermal, and structural state before abuse, leaving the literature on aged cells apparently contradictory. This review establishes an aging-aware interpretive framework that separates three levels commonly conflated: the boundary conditions governing deformation, the study-specific criteria and evidence strength behind a declared electrical event, and the post-trigger hazard progression captured within the available monitoring window. A descriptive synthesis of 22 normalized fresh-to-aged comparisons from 13 primary studies shows no universal aging-driven shift of the reported comparison event toward earlier or later force–displacement states, with force and displacement changing in the same direction in only about half of the cases. An apparent format-associated displacement pattern is substantially attenuated when the pouch-cell displacement ratios are normalized by the respective initial cell thicknesses: the pouch-cell median displacement ratio decreases from 1.07 to approximately 1.00, and the remaining variation differs across aging routes and states of charge, although their individual contributions cannot be separated in the available dataset. Many apparent contradictions likewise stem from non-equivalent mechanical boundary conditions and trigger definitions, and continuity of confinement—especially for pouch cells aged under stack pressure and tested in a relaxed state—is identified as a frequently overlooked interpretive variable, although no controlled aged-cell study has yet isolated its contribution. An earlier-reported trigger does not necessarily imply a more severe outcome. We distill these requirements into a tier-resolved reporting checklist, providing a more rigorous and reusable basis for abuse-test interpretation, model development, and safety qualification of batteries intended for long service life and second-life deployment.
Uncertainty-Aware Diffusion Model for Multimodal Highway Trajectory Prediction via DDIM Sampling
(2026)
Energy- and Runtime-Efficient Trajectory Planning via SIMD Vectorization with Reduced Precision
(2026)
An essential objective of modern battery management systems is to ensure safe battery operation. The system shall issue a warning when it detects a fault condition—the earlier, the better. Reliable fault detection requires a sensitive but equally robust detection method. In battery systems, a conspicuous change in the cell-to-cell variation can be an adequate fault indicator. To detect anomalies like this, a recurring method in prior work is principal component analysis (PCA) or one of its variants. Its effectiveness depends heavily on input data preprocessing, though, a topic that is often disregarded. To raise awareness of proper preprocessing, we investigate common techniques in terms of their impact on PCA-based fault detection. We take thermal faults and internal short circuits in battery systems as prototypical examples for our investigation. Our results highlight the importance of selecting appropriate preprocessing for the problem at hand. Well-matched preprocessing shapes the input data such that the theoretical requirements of PCA are met to a greater extent, which enhances overall detection performance. Based on this understanding, we propose a combination of outlier-robust sample studentization and Pareto scaling that improves fault detection compared with alternatives from prior work in our exemplary application. The detection sensitivity and robustness are greatly enhanced, particularly for minor faults, without adding significant computational complexity.
Experimental Performance Comparison of Four Different Hysteresis Models for Lithium-Ion Cells
(2026)
In this paper, four versions of hysteresis models parameterized by experimental data for nickel manganese cobalt (NMC) lithium-ion cells are compared. Starting from simple 1 to 5 RC models that only account for hysteresis by averaging open circuit voltage (OCV) curves measured for charge and discharge direction, three model extensions for calculating the hysteresis-biased OCV curve are investigated. Therefore, the nRC models are taken as base models and combined with the extended Preisach model, including a modified version (EPM and mEPM), which calculate the OCV in charge and discharge direction separately and thus require a complex parameterization profile. A one state model (OSM), which simply extends the nRC model by adding a hysteresis voltage source to the model structure, not only requires less parameterization efforts than the EPM and mEPM, but in combination with a simple 1RC model also shows the best model performance demonstrated by the lowest root mean square error (RMSE). The OSM models are compared to a second cell chemistry (lithium-ironphosphate), showing a decent performance, especially for medium-range state of charge values.
Impact of Hysteresis on Calendar Aging Mechanisms on Three‐Electrode Cells With Silicon‐Rich Anodes
(2026)
One promising strategy to increase the energy density of lithium‐ion batteries is to increase the silicon (Si) content in the anode. However, an increasing amount of Si is a challenge for lifetime and diagnosis, as it suffers from high volume expansion and strong voltage hysteresis. While cyclic aging dominates current research, calendar aging remains still comparatively underexplored. Therefore, we present calendar aging results of Si‐rich three‐electrode lab cells, focusing on voltage hysteresis, loss of active material, and electrode‐specific aging. We utilize OCV and float current analysis to assign electrode‐specific aging. Both methods have shown promising results for pure graphite cells and are here transferred to cells with 69wt% Si combined with NCA cathode. The tests are conducted at the target state‐of‐charge/voltage, approached from both charge and discharge directions. We found no loss of anode‐active material in the cells, but strong voltage hysteresis. As assigning the anode voltage time‐series data to the OCV curve was not possible, anode aging was calculated indirectly from cathode aging and loss of lithium inventory. Anode and cathode aging increased with electrode potential, full‐cell voltage, and SOC; however, no parameter exhibited a significantly strong correlation due to the limited accuracy of the reference electrode.
Cooperative perception enabled by Vehicle-to-Everything (V2X) communication enhances autonomous driving safety by creating a unified environmental representation through shared sensory data. While recent works have advanced multi-agent fusion for improved perception, uncertainty quantification in such cooperative frameworks remains largely unexplored. This paper introduces Hyper-V2X, a hypernetwork-based framework for estimating both epistemic and aleatoric uncertainties in V2X-based perception. Specifically, we propose a partial weight generation scheme and V2X context embedding module that conditions a Bayesian hypernetwork on fused multi-agent features to generate weight distributions for stochastic Bird's-Eye-View (BEV) segmentation. Unlike existing deterministic BEV models, Hyper-V2X enables efficient uncertainty estimation with little computation overhead. Our approach is architecture-agnostic, and can be seamlessly integrating with modern cooperative backbones such as CoBEVT. Experiments on the OPV2V benchmark demonstrate that Hyper-V2X provides accurate, well-calibrated uncertainty estimates and improves overall perception reliability.
Li-Ion batteries still prove to be difficult to extinguish throughout many experimental studies. The effectivity of different extinguishing agents has been analyzed in this study. Thermal runaway has been initiated in modules via external heat and different extinguishing agents have been applied on the modules to compare the effectiveness of their extinguishing properties. The study provides a reference for future choice of extinguishing agent in the event of a li-ion battery fire.
The present work addresses the parallel pack formation in multilevel inverters. In addition to examining the influence of the quantity of energy storage units within the parallel pack on energy losses, detailed investigation is also conducted into the impact of the resistance ratio between the switch and the energy storage unit paths. Besides the consideration of the potential savings in energy losses, which can be more than 15 % compared to a pure series mode, the problem of maximum current load on the outermost energy storage units in a parallel pack is explained in detail. Using the Helmholtz superposition principle, it is shown that, depending on the resistance ratio of the energy storage unit paths to the switch paths, a worst-case current divergence up to 100 % can occur between the mid and outermost storage units. Therefore, this paper additionally presents a parallel pack formation strategy that addresses this edge problem achieving a more balanced percentage of the edge storage units. This measure facilitates reducing the observed state-of-charge drift in alternative formation strategies to below 1 %.
These results provide valuable design guidelines for multilevel inverter systems, in particular regarding the optimal formation of parallel packs under dynamic operating conditions. The application of the developed radical algorithm enables improved energy efficiency as well as a more balanced utilization of the inherent energy storage units, which is of direct relevance for enhancing system reliability and lifetime in electric vehicle and stationary energy storage applications.
This paper evaluates technical aspects of the Directives on periodic roadworthiness testing (2014/45/EU) and roadside inspection of commercial vehicles (2014/47/EU). Key findings focus on harmonising minimum content for Periodic Technical Inspection and Roadside Inspection requirements across Member States and establishing a cross-border data-exchange platform for registration, driver licence and inspection data. For remote sensing, comparative campaigns across Member States are recommended, noting its benefits while zero-emission vehicle uptake remains low. This document was provided by Policy Department B at the request of the TRAN Committee.
Active Safety: Decision-Making Using Potential Fields for Path-Following in Autonomous Driving
(2026)
Motion planning is vital for autonomous driving as well as safely transporting passengers and goods. A core element of motion planning is decision-making and its implication for trajectory generation in the context of scenario-independent and time-dependent motion planning. This article presents a novel motion planning framework with an extended operational design domain (ODD) to shift boundaries towards scenario-independent decision-making for a given path, focusing on obstacle and crash avoidance. A nonlinear model predictive path-following controller (NMPFC) is utilized to obtain a decision with the related trajectory and track the trajectory simultaneously. This path-following framework is fed by an ego-motion prediction module and an environment representation via an artificial potential field (APF) used for optimal non-predefined decision-making. A weighted topographic environment model forces the NMPFC to avoid critical trajectories defined by their level of risk with respect to physical state and actuator constraints. The parameterization of this APF is challenging, such that a multi-layer definition and implementation of the APF for more accurate decision-making is required for the proposed active safety features. The optimizer’s cost function directly encapsulates and manages potential surrounding risks, while constraint relaxation maintains a limit on the computation time per optimization cycle. This synergistic interaction ultimately ensures recursive feasibility, which is mandatory for safe operation. Finally, we present a virtual testing environment consisting of Matlab/Simulink and IPG CarMaker to demonstrate the system’s abilities under different test cases.
In-situ formation of copper nanoparticles using organometallic copper(II) formate-amine complexes
(2026)
Copper(II) formate tetrahydrate is complexed with three amine ligands: amino-2-propanol, hexylamine and 2-(ethylamino)ethanol to develop copper particle-free inks for low-temperature (<130 °C) in-situ formation of copper nanoparticles for printed electronics. This study investigates how ligand structure influences complex formation, thermal decomposition behaviour and the resulting particle morphology. Fourier transform infrared spectroscopy confirms coordination between copper(II) formate and the amines through characteristic shifts in N-H and formate-related bands, indicating ligand-dependent coordination strength. Differential scanning calorimetry and thermogravimetric analysis show that complexation significantly reduces the decomposition temperature compared to pristine copper(II) formate, enabling formation below 150 °C. Activation energies determined using Kissinger and Ozawa methods range from 96 to 103 kJ/mol, lower than that of pristine copper(II) formate (∼115 ± 10 kJ/mol), demonstrating that amine ligands decrease the energy barrier for copper(II) reduction. Scanning electron microscopy reveals that thermal processing parameters (temperature, time and heating rate) and ligand structure strongly affect the formation of particles. Hexylamine produces uniform, densely packed spherical particles (0.3-1.2 μm) with low porosity across the investigated temperature range. Amino-2-propanol yields small particles (0.4-0.6 μm) only at 130 °C, whereas lower temperatures lead to agglomeration. In contrast, 2-(ethylamino)ethanol results in irregular and porous particles due to weaker coordination and higher volatility. Overall, ligand structure governs decomposition kinetics and particle morphology, providing a rational basis of designing low-temperature Cu particle-free inks for flexible printed electronics.
Electrochemical aging can alter the mechanical abuse tolerance of lithium-ion cells, but evidence for large-format tabless cylindrical cells remains limited. This study investigates commercial steel-cased 4695 cells under quasi-static hemispherical indentation at 100% State-of-Charge. Fresh cells were compared with two aged groups brought to 80% remaining capacity by either room-temperature cycling at 20 °C and 20 A or low-temperature/high-current cycling at −10 °C and 45 A. Aging shifted the onset of a major internal short circuit to lower displacement, force, and absorbed mechanical work. Relative to fresh cells, the mean displacement at internal short-circuit onset decreased by 15.9% after aging at 20 °C and 20 A and by 22.1% after aging at −10 °C and 45 A, while the corresponding force decreased by 10.8% and 19.4%. The absorbed mechanical work to short-circuit onset decreased by 24.0% and 37.3%, respectively. Peak surface temperatures did not clearly separate the groups, whereas integrating the surface-temperature rise over the first 30 s after short-circuit onset revealed an increase from 6894 Ks in fresh cells to 9872 Ks and 13,777 Ks in the two aged groups. The experiments also revealed a change in observed venting behavior, with top-terminal venting occurring more frequently in aged cells. These results indicate that, under the tested conditions, aging history can reduce mechanical abuse tolerance and modify post-failure severity in large-format cylindrical cells.
Cascaded multilevel inverters constitute a promising system concept for battery electric powertrains due to their high efficiency, low harmonic distortion, and advanced battery management capabilities. This study presents a novel electro-thermal simulation framework for the symmetrical Parallel Enhanced Commutation Integrated Nested (PECIN) multilevel inverter. The proposed model employs a control-oriented approach that enables the development and evaluation of advanced inverter and battery control algorithms, which exploit the extensive series-parallel reconfiguration capabilities of the PECIN topology. The framework is based on electrical and thermal equivalent circuit models to capture physical behavior and cross-domain interactions. Electrical network analysis employs algorithms that iterate over each phase-arm network, replacing high-dimensional matrix inversions and thereby enhancing computational efficiency. The overall model is readily adaptable to various system configurations, including different AC and DC charging modes, and scalable with respect to the number of submodules and phases. Simulation results for a 31-level multilevel inverter in a three-phase AC charging configuration demonstrate the model’s operational capabilities. Execution time analysis shows that the current distribution calculation is the key contributor to computational effort as the number of submodules increases, resulting in a quadratic growth of the overall computational time.
Retrieval-Augmented Generation (RAG) systems critically depend on retrieval quality, yet no systematic comparison of modern retrieval methods exists for heterogeneous documents containing both text and tabular data. We benchmark ten retrieval strategies spanning sparse, dense, hybrid fusion, cross-encoder reranking, query expansion, index augmentation, and adaptive retrieval on a challenging financial QA benchmark of 23,088 queries over 7,318 documents with mixed text-and-table content. We evaluate retrieval quality via Recall@k, MRR, and nDCG, and end-to-end generation quality via Number Match, with paired bootstrap significance testing. Our results show that (1) a two-stage pipeline combining hybrid retrieval with neural reranking achieves Recall@5 of 0.816 and MRR@3 of 0.605, outperforming all single-stage methods by a large margin; (2) BM25 outperforms state-of-the-art dense retrieval on financial documents, challenging the common assumption that semantic search universally dominates; and (3) query expansion methods (HyDE, multi-query) and adaptive retrieval provide limited benefit for precise numerical queries, while contextual retrieval yields consistent gains. We provide ablation studies on fusion methods and reranker depth, actionable cost-accuracy recommendations, and release our full benchmark code.
Cellular Vehicle-to-X (Cellular V2X) is a communication technology that aims to facilitate the communication among vehicles and with the roadside infrastructure. Introduced with LTE Release 14, Cellular V2X enables device-to-device communication to support road safety and traffic efficiency applications. We present Artery-C, a simulation framework for the performance evaluation of Cellular V2X protocols and V2X applications. Our simulator relies on the simulation framework SimuLTE and substantially extends it by implementing control and user planes. Besides the vehicle-to-network communication via the up-/downlink interface, it provides vehicle-to-vehicle and vehicle-infrastructure communication via the sidelink interface using the managed and the unmanaged mode of Cellular V2X (mode 3 and 4, respectively). The simulator also implements advanced features of 5G mobile networks, such as variable numerologies. For the transmission of of V2X messages, it adds a non-IP interface. Artery-C integrates seamlessly into the simulation framework Artery, which enables the simulation of standardized V2X messages at the facilities layer as well as the coupling to the mobility simulator SUMO. A specific feature of Artery-C is the support of dynamic switching between all modes of Cellular V2X. In order to demonstrate the capabilities of Artery-C, we evaluate V2X-based platooning as a representative use case and present results for mode 3, mode 4 and mode switching in a highway scenario.
Magnetic Resonance Fingerprinting (MRF) and other highly accelerated transient-state parameter mapping techniques enable simultaneous quantification of multiple tissue properties, but often suffer from aliasing artifacts due to compressed sampling. Incorporating spatial image priors can mitigate these artifacts, and deep learning has shown strong potential when large training datasets are available. However, extending this paradigm to MRF-type sequences remains challenging due to the scarcity of quantitative imaging data for training. Can this limitation be overcome by leveraging sources of training data from clinically-routine weighted MRI images? To this end, we introduce MRI2Qmap, a plug-and-play quantitative reconstruction framework that integrates the physical acquisition model with priors learned from deep denoising autoencoders pretrained on large multimodal weighted-MRI datasets. MRI2Qmap demonstrates that spatial-domain structural priors learned from independently acquired datasets of routine weighted-MRI images can be effectively used for quantitative MRI reconstruction. The proposed method is validated on highly accelerated 3D whole-brain MRF data from both in-vivo and simulated acquisitions, achieving competitive or superior performance relative to existing baselines without requiring ground-truth quantitative imaging data for training. By decoupling quantitative reconstruction from the need for ground-truth MRF training data, this framework points toward a scalable paradigm for quantitative MRI that can capitalize on the large and growing repositories of routine clinical MRI.
Das Vorhaben 5GoIng hatte das Ziel, 5G-basierte Anwendungen in den Bereichen Verkehrssicherheit, Nachhaltigkeit und Smart City zu demonstrieren, ein 5G Testfeld im Digitalen Testfeld "Erste Meile" in Ingolstadt aufzubauen, sowie Aspekte der Technologieakzeptanz, interkommunale Zusammenarbeit und die Förderung der Startup-Infrastruktur zu adressieren. Das 5G-Testfeld dient durch die Nutzung öffentlicher Straßenabschnitte als Schaufenster für "Vernetzte Mobilität" und eröffnet die Gelegenheit, den Nutzen der 5G-Technologien direkt zu erleben. 5GoIng adressiert sowohl die drei technischen Schwerpunkte Smart City, Verkehrssicherheit und Nachhaltigkeit, als auch die gesellschaftsrelevanten Kernpunkte Akzeptanz, interkommunale Zusammenarbeit und Förderung der Startup-Infrastruktur.
