磷酸铁锂正极锂离子电池的高温循环性能

摘要

The cycle performance of lithium iron phosphate (LiFePO4) cathode Li-ion battery was studied. When the battery cycled with 1 C,100% depth of discharge (DOD),the cycle number under normal temperature was more than 1 800 times,it was only about 200 times under 60 ℃ high temperature. The growth of internal resistance and thickness of the battery under high temperature was bigger than under normal temperature, which indicated that the capacity decay was accelerated by high temperature. The capacity under normal temperature increased about 9.46% after injecting electrolyte into the battery which suffered at high temperature cycle. The lack of electrolyte was one of the reasons that caused the decay of cycle performance of battery under high temperature,but it wasn't the primary reason.%对磷酸铁锂(LiFePO4)正极锂离子电池的循环性能进行研究.电池以1C、100％放电深度(DOD)循环,在常温下的循环次数可达1 800次以上,而在60℃高温下只有200次左右.在高温下循环后,电池的内阻和厚度增幅大于常温时,说明高温会加速容量衰减.对高温循环失效的电池补加电解液,常温放电容量提高了约9.46％.电解液匮乏是电池高温循环性能变差的原因之一,但不是主要原因.