Thermal runaway is a critical safety concern in lithium-ion battery systems, emphasising the necessity to comprehend its behaviour in various modular setups. This research compares thermal runaway propagation in different modular configurations of lithium-ion batteries by analysing parameters such as cell spacing and distribution, application of phase change materials (PCMs), and implementing insulating materials. The study at the module level includes experimental validation and employs a comprehensive model considering heat transfer due to electrical performance and thermal runaway phenomena. It aims to identify the most effective modular configuration for mitigating thermal runaway risks and enhancing battery safety. The findings provide valuable insights into the design and operation of modular lithium-ion battery systems, guiding engineers and researchers in implementing best practices to improve safety and performance across various applications.
The SAE J1772 charging standard was first published in 1996, evolving to the present form factor (920vdc/500A capable couplers). In 2022 the existing Tesla North American Charging ‘standard’ (NACS) specification (TS-0023666) was published and offered without patent limitations to the level of detail in the published specification. https://digitalassets.tesla.com/tesla-contents/image/upload/North-American-Charging-Standard-Technical-Specification-TS-0023666 In 2023 several North American vehicle OEMs announced that they would offer the NACS inlet on their vehicles in 2025. The SAE J3400 North American Charging System standard work group was launched in July 2023 with the intent of publishing a first draft Technical Information Reference (TIR) by late 2023. https://www.sae.org/standards/content/j3400/ This paper covers the process and limitations of publishing that TIR, ASAP.
In this paper, water droplet dynamics in FC channels were investigated by applying numerical and experimental methodologies. Specifically, digital imaging with high-spatial resolution was applied for characterising the micro-channel surface and defining the texture of the Gas Diffusion Layer (GDL) of a Membrane electrode assembly (MEA). The optical results allowed the definition of a 3D geometry of the GDL to use in CFD simulations. Moreover, a custom procedure of image processing permitted the estimation of the contact angles of droplets deposited on the GDL (123°) and channel walls (50°-60°) for a wide range of droplet size (0.3-1.2mm). The determined specifications were used as boundary conditions for a 3D CFD two phase simulation employing the Volume of Fluid (VOF) model. Droplets were initialized on the walls and their dynamics were studied under increasing air flow, up to 20 m/s.