A comparative study on the thermal runaway process mechanism of a pouch cell based on Li-rich layered oxide cathodes with different activation degrees.

Li-rich layered oxide (LLO) is regarded as one of the most promising candidates for the next-generation batteries. At present, most of the research studies are focusing on the normal electrochemical properties of LLOs, while safety issues of the cells are neglected. To address this problem, this article systematically investigates the thermal runaway (TR) process of the pouch cell based on LLOs and elucidates how different activation degrees influence the thermal stability of the cathode material and cell, through various thermal analysis methods.

New information about the cyclable capacity fading process of a pouch cell with Li-rich layered oxide cathodes.

Most studies investigate the cyclable capacity fading mechanism of Li-rich layered oxides (LLOs) from the microscopic structure level, lacking discussions about how the structure degradation influences the performance of the pouch cell precisely and quantitatively. Based on the analysis of the evolution of key parameters during the whole cycling period, a new transition-type fading mechanism is proposed. From the early-to-middle stage of the cycling period, polarization increases, most of which is interface-related, causing about 67% of the whole capacity loss.