Abstract:In order to explore the thermal effect of aluminum and pouch lithium iron phosphate(LFP) single cell on surrounding cells under overcharge condition, the thermal propagation behavior of aluminum LFP and pouch LFP under three operating conditions which include only single cell, two cell batteries close to each other, and two cell batteries separated by 1 cm are respectively studied. In the experiment, the 48 A·h pouch cell and 24 A·h aluminum cell are overcharged with a constant current of 0.5 C. Visible light monitoring, infrared monitoring and multi-channel temperature recorders are used to monitor the external appearance, external temperature and battery surface temperature changes in real time. The experimental result shows that during the overcharge, the temperature rise of the aluminum overcharged cell is 65.5 ℃and the average temperature rise rate is 0.039 2 ℃/s. The temperature rise of the pouch overcharged cell is 57.3 ℃and the average temperature rise rate is 0.014 3 ℃/s. The maximum temperature rise of adjacent aluminum cell is 44 ℃and the maximum temperature rise rate is 0.031 2 ℃/s. The maximum temperature rise of adjacent pouch cell is 7.9 ℃and the maximum temperature rise rate is 0.006 3 ℃/s. After overcharged, the expansion force generated by the pouch cell has greater impact on adjacent cellsand the mechanical stress generated by adjacent cells is greater. The experimental results can provide theoretical and experimental references for studying the influence of thermal radiation of aluminum or pouch batteries inside the module.