本文通过磷酸铁锂/碳电池研究了电解液添加剂氟代乙烯碳酸酯（FEC）对电池低温性能的影响. 电池充放电实验证明，FEC添加剂能够在负极表面形成良好的固体电解质界面层（SEI）. 电解液中添加5% FEC后，电池-40 oC低温放电容量保持率可以从31.7%提高至43.7%，还提高了电池放电电压平台. 交流阻抗测试表明，FEC的加入能够有效降低电池的界面传荷阻抗（Rct）. 参比电极测试表明，其主要是降低了碳负极的低温极化.
The effects of fluoroethylene carbonate (FEC) on the low temperature performance of lithium ion phosphate full battery are evaluated by different techniques. By addition of 5 wt% FEC into a commercial electrolyte, effective solid electrolyte interface (SEI) film can be formed on the graphite electrodes, the discharge capacity retention at -40 oC was increased from 31.7% to 43.7%, and the discharge voltage plateau of the cell is raised. This is attributed to a reduced charge transfer resistance and a lowered polarization on the graphite electrode by electrochemical impedance spectroscopy (EIS) and reference electrode test.
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