In this presentation, various aspects of thermal runaway and propagation in Li-ion batteries, including thermal runaway detection criteria and questions facing development of a regulatory test procedure, are discussed. Liquid, gas, and solid emissions from Li-ion batteries in several scenarios including battery fire are analyzed allowing more quantitative risk assessment of such emissions.

The journey of discovery his group has made over the past ten years in understanding lithium-ion battery degradation, how to model it, and how to diagnose it. The journey began with pioneering work demonstrating how different thermal management approaches strongly affected the degradation rates of lithium-ion pouch cells. At around the same time, the group began working on understanding and modelling the physical mechanisms of degradation.

As immersion cooling systems dissipate heat from battery cells faster and more efficiently than state-of-the-art solutions, e.g.; with cooling plates, the interest in this technology is rising continuously. With coolants coming into direct contact with battery cells, fulfilling cleanliness requirements for the liquids is essential to prevent breakdown of dielectric properties. This presentation highlights solutions for particle filtration and water removal from Polyol Ester Oils in an OEM application.

Thermal runaway behavior of commercial cylindrical LIB was evaluated using Accelerating Rate Calorimetry (ARC). With the Heat-Wait-Seek (HWS) test thermal abuse was studied and exothermal reaction temperature rates were evaluated and compared for different states of charge of 30, 60, 80, and 100%. Different cathode materials were studied, such as NCA, NMC, and LFP, as well as a comparison of type 18650 and type 21700 cells was done.

The role of cell-to-cell gap, thermal conductivity of the interstitial material, and radiative properties of the partition between cells will be discussed. It will be shown that a careful thermal design of the battery pack may help mitigate several thermal runaway propagation related challenges.

High-voltage battery packs are part of every electrically powered vehicle. They are used in purely electric vehicles (EVs), hybrid vehicles (HEVs), but also in vehicles with fuel cell drive (FCVs). The battery packs have to be tested against water ingress - often according to IP67 - but also against coolant loss. The presentation will show how a suitable leakage rate specification can be determined and which testing processes can be used.

The race for the best cell format is open: From cylindric to pouch to prismatic approaches, all formats are currently out on the automotive battery market. In our talk we will shed light on the pros and cons of different formats and share insights we gained by opening and physically modelling a large variety of the cells, which are currently on the market.

We compare the cell formats PHEV1, pouch, 21700, and 18650 with the same cell chemistry on pilot-scale. Conclusions are drawn on the effect of cell design on rate capability, cell resistance, heating behavior, and cycling aging. The results are put into context with commercial cells.

In order to help align the two seemingly contradicting goals of highly flexible processes and large produced quantities, a new concept for the cell stacking process will be demonstrated. By interconnecting the traditional discrete stacking process and a continuous cutting operation, fast changes in regard to electrode dimension are made possible.

Thermoplastic composite offers several solutions for battery pack enclosures such as flexibility of design range with parts integration, high productivity performance, lightweight, halogen-free, positive end-of-life with recyclable materials.

Our recent work on preventing thermal runaway propagation (TRP) by next-generation thermal barriers is presented. The focus is not only on our product design and approach, but also on best practices for bringing the barriers into the actual application.

As price, quality and carbon footprint are playing an increasingly important role in the future of e-mobility, new kiln concepts are needed to reach these targets. The currently available kilns cannot provide the required performance for the heat treatment of the electrode raw materials or even solid-state battery systems. See how ONEJOON´s advanced kiln concepts provide revolutionary improvements in the heat treatment technology of cathode, anode, and solid electrolyte material systems. 

Battery models are only as good as the parameters which define them – poor temperature control during parameterisation experiments leads to error in battery model parameters, yet convection cooling remains the temperature control method of choice across the automotive industry. The problem will worsen in years to come as high-rate requirements and energy density continue to increase. We must use temperature as a controlled input rather than a poorly controlled variable, and add an additional dimension to the performance of our battery models and battery management system.

This work aims to develop a parameter identification framework that is suitable for fast and accurate identification of physical parameters of electrochemical models under real-world operation. The proposed data-driven parameter identification framework not only shows significant performance improvement compared with the other data-driven methods but also shows a higher identification accuracy compared with the state-of-the-art experimental identification method.

Current “state-of-the-art” monitoring and control techniques for battery cells rely on full-cell potential measurement and occasional surface temperature measurements. However, electrochemical cells are complex multi-component devices and as such these techniques have poor resolution, limiting applicability. To unlock the full battery performance without jeopardising safety, we enable live in-situ thermodynamic characterisation utilising a combination of developments on micron-scale sensor assemblies facilitating internal power mapping.

The Chinese government mandates that passengers must have a 5-minute window to exit their vehicle after detection of thermal runaway. While this is a step forward, a better goal is to stop thermal propagation. Single-cell thermal runaways that propagate to module-, pack-, or vehicle-level will, even at low incident rates, dampen acceptance of BEVs. Discover how aerogel-based thermal barrier materials can help achieve this goal within space, weight, and cost constraints.

This presentation will share the details of QuantumScape’s groundbreaking solid-state batteries technology with lithium-metal anodes and discuss how QuantumScape addresses the limitations of traditional lithium-ion batteries and previous attempts at solid-state technology, including charge time, cycle life, safety, and operating temperature.

Solid-state lithium-ion batteries are predicted to become mainstream in the next few years due to their superior performance, such as high energy density (350Wh/kg), wide operating temperature (-10 to 70C), excellent safety, and lower cost. Solid-state batteries also offer a higher cell voltage of nearly 5V. However, the life cycle of the solid-state batteries may be much lower than the current lithium-ion battery. Hence, a new generation of battery management systems is necessary to manage the future solid-state lithium-ion batteries that can handle the high cell voltage and optimize the life cycle.

While virtual development and use of simulations are increasingly adopted by companies globally, combining the development phase with actual performance in the field remains difficult. Hybrid models are a unique technology that enables accurate development insights and assesses likely warranty cases across fleets, whilst understanding end-of-life challenges. A current case from the automotive industry will be presented.