Full-cycle electrochemical-thermal coupling analysis for commercial lithium-ion batteries

Lithium-ion batteries (LIBs) are widely used in modern industrial products, and their thermal safety has become an emerging concern. In this paper, an electrochemical-thermal coupling model has been established to simulate the electrochemical reaction and heat transfer. A series of charge–discharge and pulse tests for three types of batteries (14650, 18650, and 26650) with varied geometry sizes are designed to verify the rationality and consistency of the model. The simulation shows that the temperature of the tested battery rises sharply during the discharge process, then peaks at the end of the discharge, which is consistently validated with a higher discharge rate and larger battery size. Furthermore, the computational cost was much saved without compromising accuracy. Therefore, the proposed electrochemical-thermal coupling strategy has paved a new way to monitor the running batteries as well as provide early detection and prevention for safe applications.