高功率锂离子蓄电池制备与性能研究

以尖晶石锰酸锂为正极材料,制备了混合动力汽车(HEV)用8Ah高功率锂离子蓄电池,电池容量、质量及荷电保持性能一致性良好。性能测试结果表明:单体电池25.0C持续放电比功率达到1517W/kg;-30℃下1.0C放电容量是25℃下的90%;室温循环700周容量保持87%;电池在针刺、挤压和短路的情况下,不爆炸,不起火,具有较好的安全性;室温下电池循环过程中充放电效率接近100%,而高温下只有97%;高温下电池的充电容量和放电容量比室温下衰减快,而在充电过程中高温充电容量的变化比室温下复杂得多。

Preparation and performance of high power lithium secondary battery

The 8 Ah high power lithium secondary battery for hybrid electric vehicle (HEV) was prepared with LIMn2O4 as cathode material. The uniformity of capacity, weight and charge retention was good. The performance test results show that the continuous discharge power density of the cell is 1 517 W/kg at 25.0 C. At -30 ℃, the discharge capacity retains 90% of that at 25 ℃ at 1.0 C. After 700 cycles with 1.0 C, the capacity retention rate is 87%. The cell neither explodes nor catches fire when the cell is punctured, pressed and short-circuited. The safety characteristic of the cell is good. Charge-discharge efficiency is almost 100 % at room temperature, while only 97 % at elevated temperature. Both charge and discharge capacity fade at high temperature are faster than those at room temperature, and in the process of charging, the changes of charging capacity at high-temperature are much more complex than those at room temperature.