Safety tests by means of Accelerating Rate Calorimetry (ARC) have been conducted on cylindrical type 21700 cells with NCA and LFP chemistry. The temperature where thermal runaway is stoppable was found, as well as when the chain reaction can't be stopped anymore. Two modified heat-wait-seek (HWS) experiments have been conducted, one with intensive cooling of the cell and the other with environmental heat dissipation without active cooling.

An NMC 811 21700 cell module is subjected to immersion cooling during fast charging and nail penetration testing. The results are compared to baseline without immersion cooling and benefits and shortcomings are analyzed.

Micro-USB Li-ion batteries (LIBs) are the latest devices in the market where lithium-ion batteries come fitted with a micro-USB port for direct charging through any USB power supply. The micro-USB batteries are fitted with a circuit board that is expected to not only provide the charge protocol but also expected to be independently fault-tolerant to all electrical off-nominal conditions. The nominal and off-nominal characteristics of micro-USB batteries from six manufacturers were studied. The results of these studies will be presented.

With the increasing incidence of fire and catastrophic failure of electric vehicles, the necessity of an advanced battery management system and safety framework became crucial. The talk will focus on the importance of intelligent state estimation and control in lithium-ion battery management systems for transportation electrification applications. The current issues and challenges will be also discussed to highlight the scope of future research and development.

The Battery Management System (BMS) has the crucial task of keeping a high-voltage battery pack safe. BMS relies on measured data from battery packs at different levels through different sensors. Capturing relevant data with proper interpretation is crucial for correct diagnosis. In this presentation, we will discuss the unreliability issues of battery safety and its diagnosis for different emerging sensors. We will present a diagnostic evaluation tool for uniformly testing and validating the battery safety-specific sensors, which could accelerate their implementation in advanced BMS.

This study introduces an electrical equivalent circuit model of lithium-ion cells developed in the MATLAB/Simulink environment. Cell SoC, SoH, temperature, and C-rate are considered for more accurate cell impedance prediction, and the simulation results are verified with the measurement results. The developed model is suitable for use in cell SoC and SoH monitoring studies by successfully outputting cell impedance through real-time prediction of cell voltage during discharge.

Range anxiety is a key reason that consumers are reluctant to embrace electric vehicles (EVs). However, none of today’s EVs allow fast charging in cold or even cool temperatures due to the risk of lithium plating, the formation of metallic lithium that drastically reduces battery life and even results in safety hazards. Here, we present an approach that enables 15-minute fast charging of Li-ion batteries at any temperature (-50 °C).

A battery cell in which a liquid electrolyte is disposed and an acoustic transducer in mechanical communication with the battery cell. The acoustic transducer is configured to generate acoustic waves. The acoustic waves have a wavelength larger than a dimension of the battery cell such that the acoustic waves generate cavitation bubbles in the electrolyte.

A novel parametrisation testing technique is presented. It's then parametrised using this testing technique and compared to a model parametrised using current common testing techniques. This comparison is conducted using a WLTP (worldwide harmonised light vehicle test procedure) drive cycle. As part of the validation, the experiments were conducted at different temperatures and repeated using two different temperature control methods: a climate chamber and a Peltier element temperature control method.

Physics-based battery-cell models used by advanced BMS depend on knowledge of the electrodes’ OCP relationships as functions of stoichiometry. The utility of these relationships depends on how accurately they correspond to the true local absolute stoichiometry. This talk proposes a nondestructive lab test and corresponding data-processing method that can calibrate an initial relative OCP-function estimate to produce an absolute OCP-function estimate that increases the accuracy of the cell model.

State-of-the-art BMS rely on highly accurate battery models and powerful algorithms to obtain useful estimates of available power for safe battery operation. This talk presents - in tutorial fashion - an overview of state-of-power (SOP) estimation for lithium-ion batteries. Depicted graphically in the context of the voltage-current product, the talk explains the various definitions of SOP and the variety of model-algorithm approaches used in its calculation. Examples are demonstrated via simulation.