Aging-related thermal conductivity change in LFP automotive batteries: characterization and understanding through internal optical-fiber temperature sensors, ex-situ and modelling analyses
Understanding aging mechanisms of lithium-ion batteries (LIBs) is essential to assess long-term performance and durability, with temperature playing a key role in both degradation kinetics and thermal behavior. Within the Horizon Europe project AutoMAT, this work investigates aging-induced variations in thermo-physical properties of LIBs—namely radial and axial thermal conductivity (Kr, Kl) and specific heat capacity—which […]
Experimental investigation and simulation of thermal runaway behaviour of cylindrical and prismatic LFP cells
Thermal runaway remains a critical safety concern for lithium-ion batteries, yet its reproducibility under varying conditions is not well understood. LFP cells are generally considered safer in terms of thermal runaway. This study was performed using series production LFP cells to find out what their actual limitations are to design a safer battery pack. Therefore, […]
Aging-related thermal conductivity change in LFP automotive batteries: characterization and understanding through internal optical-fiber temperature sensors, ex-situ and modelling analyses
Understanding aging mechanisms of lithium-ion batteries (LIBs) is essential to assess long-term performance and durability, with temperature playing a key role in both degradation kinetics and thermal behavior. Within the Horizon Europe project AutoMAT, this work investigates aging-induced variations in thermo-physical properties of LIBs—namely radial and axial thermal conductivity (Kr, Kl) and specific heat capacity—which […]
Multiphysics Simulation of Lateral Impact Effects on EV Battery Safety: From Mechanical Deformation to Thermal Runaway Prediction
Our methodology integrates various physics domains, commencing with detailed crash simulations. These simulations analyze the mechanical deformation experienced by battery cells and entire packs under a side pole impact scenario. A crucial step involves determining the critical strain thresholds at which an internal short circuit is predicted to initiate. This data-driven insight is then seamlessly […]
Physics-Based EIS Simulation for Real-Time, Impedance-Driven Battery Diagnostics in BMS
Impedance analysis of lithium-ion batteries plays a key role in understanding internal electrochemical processes and enabling state estimation and health diagnostics. However, conventional electrochemical impedance spectroscopy (EIS) relies on small-signal sinusoidal excitation and ideal measurement conditions, which are rarely met in practical applications. In systems such as electric vehicles and power electronics, batteries are subjected […]
Vibration Monitoring of Lithium-Ion Batteries for Early Failure Prediction
The rapid expansion of the Battery Energy Storage Systems (BESS) market has been accompanied by increasing reports of system failures, including fires and explosions, underscoring the urgent need for improved safety strategies. This work presents a novel vibration‑based sensing approach for the early detection of thermal runaway in lithium‑ion battery cells used in BESS applications. […]
Modeling Battery Vent Gas Ignition during Thermal Runaway: From Chemical Kinetics to System-Level Safety
Fulfilling safety requirements remains a key challenge in the development of future battery systems. With increasingly stringent thermal propagation (TP) regulations, such as the new Chinese standard GB 38031-2025 mandating “no fire outside the battery”, system developers face growing pressure to accurately assess and mitigate fire hazards. Therefore, systematically evaluating the ignition risk of battery […]
The Power of Machine Learning to Unveil Behavioral Patterns in BEV Operation
Selecting representative behavioral patterns for battery development and validation remains a major challenge. Real-world BEV usage varies widely in current load, depth of discharge, DC charging behavior, temperature exposure, and other operational factors. As a result, identifying a suitable usage behavior pattern for a given testing purpose is difficult. However, it is crucial because battery […]
Rigorous Benchmarking of Battery Chemistries: Insights from Measuring and Modelling more than 300 Cells
As the global battery market diversifies to meet the demands of electrification, energy storage, and cost optimization, the question arises: Which cell chemistry is best suited for which application? How do emerging technologies like sodium-ion perform compared with established chemistries such as LFP and NMC? And how do the materials hold up under operation in […]
Engineering Stable Interfaces: Modifying the Surface of NMC811 with Tailored Phosphonic and Phosphinic Acids
Lithium-ion batteries are a vital part of the transition to renewable energies and electrified transportation. Ni-rich layered oxides, with at least 80 % nickel, are of particular interest due to their high specific capacity of around 200 mAh g-1 and their high average potential (ap-prox. 3.7 V vs Li/Li+).[1] Despite these advantages, a further increase […]