电池结构对锂离子电池功率性能影响

Effect of battery structure on the power performance of Li-ion battery

电池结构对锂离子电池的功率性能有重要的影响。本文研究了一种新型结构锂离子电池，并测试不同结构电池的倍率循环特性、不同倍率条件下倍率特性及不同放电电流下电池表面温度分布梯度。测试结果显示：不同倍率条件下新型结构的锂离子电池表现出较佳的倍率放电特性，20C放电容量是1C时放电容量的87．75％；新型结构设计的电池表现出良好的2CC／5DC倍率循环特性，循环850次容量保持90％左右，不同倍率放电电流下电池表面温度分布及温度梯度小，3个位置温度在63．6～74．8℃，对电池内部膜片的表面反应活性影响较小。这种新型结构电池有助于改善单体电池及电池组的综合功率性能。

The cell structure significantly affects the power characteristics of Li-ion batteries. In this paper, a Li-ion cell with new type of structure was successfully developed. And the cyclic performance, rate performance and the surface temperature gradient of the cell were tested. The testing results showed that the Li-ion cell with new structure had better discharge characteristics, the discharge capacity under 20C was 87. 75% of capacity under 1C. The new structure cell showed good 2 CC / 5 DC rate cycle characteristics, the capacity maintain 90% after 850 times. Under the condition of different discharge rate, cell surface temperature gradient was small （the temperature distribution between 63.6 ～ 74.8℃）, its influence on the surface reactivity of cell pole piece was small. The new cell structure helps to improve the power performance of cell and pack.