Etudes des phénomènes thermiques dans les batteries Li-ion.

This work relates to the thermal study of Li-ion batteries in order to develop an optimized battery thermal management system. The understanding of thermal phenomena at cell scale is essential before to undertake an approach of the battery module or pack. Galvanostatic discharges of two kind of Li ion cells are modeled to highlight thermal phenomena. The complexity of the resistive behavior of Li-ion cell led to the development of an electrochemical-thermal coupled model to get a predictive approach. Then, two experimental tests benches were designed so as to compare two battery thermal management systems (BTMS). Restrictions of air cooling highlight its disability to achieve thermal management criteria. Innovative integration of a phase change material (PCM) was then tested under several uses of the battery module. This new BTMS showed really promising performances during intensive driving cycles, failure tests, and when a fast charge is needed.