退役磷酸铁锂动力电池性能分析研究

Performance study of retired power lithium iron phosphate batteries

随着电动汽车行业的快速发展,退役动力电池数量与日俱增。分析统计了某批退役磷酸铁锂动力电池的容量、内阻、容量保持率、容量恢复率等关键参数,发现退役电池的容量和内阻出现了较大程度的离散,在梯次利用前需重新筛选配组;此外,测试了其倍率性能、表面放热特性、高低温性能、循环寿命并拆解部分电池对电极材料的物相和表面形貌进行分析,结果表明,此退役电池仍具有较好的性能,可以在使用条件相对温和的领域进行梯次利用。

With the rapid development of the electric vehicle industry, the number of retired power batteries is increasing. The key parameters such as capacity, internal resistance, capacity retention rate and capacity recovery rate of a batch of retired power lithium iron phosphate batteries were analyzed. It is found that the capacity and internal resistance of the retired batteries has a large degree of discretization, which needs to be re-screened and packed before the secondary use. In addition, its rate capability, surface heat release characteristics, high and low temperature performance, cycle life were researched, and the phase and surface morphology of the electrode material were also analyzed by dismantling part of the batteries. The results show that the retired battery still has good performance, and can be secondary use in the relatively mild conditions.