【摘要】 研究了不同电压锂离子电池及其正、负极在70℃存储时的产气现象。研究表明,随着电池电压的降低,正极侧产气量逐渐降低,负极侧产气量逐渐增加,而且低电压(电压≤3.3 V)电池负极侧产气量远大于较高电压(电压≥3.5 V)电池负极侧产气量;较低电压(电压≤3.7 V)电池的正极侧产气量小于负极侧产气量。另外,对不同电压电池负极的XRD图谱进行了分析,结果说明3.3 V以下负极几乎处于完全脱锂状态。同时,采用气相色谱测试对不同电压电池负极的产气进行成分分析,说明负极产气是负极与电解液的还原反应产生的。结合不同电压电池负极高温产气量测量结果、XRD图谱分析结果和气相色谱分析结果,证明了:在70℃高温环境存储时,锂离子电池产气主要是由于负极在完全脱锂状态下SEI膜氧化分解后与电解液的反应造成的,产气量的变化跟负极嵌锂程度相关。更多还原

【Abstract】 Gas generation phenomena during storage at 70℃for lithium ion batteries(LIBs) with different voltages are studied.The results show that with the decrease of the battery voltage,the gas generation on cathode decreases and the gas generation on anode increases,and the gas generation on anode of the low voltage(voltage ≤ 3.3 V)battery is much higher than that on anode of the high voltage(voltage≥3.5 V);the gas generation on cathode of the low voltage(voltage≤3.7 V) battery is less than that on anode.In addition,the XRD of the anode of the batteries with different voltages were analyzed.The results show that the anode below 3.3 V are almost in the state of complete lithium removal.At the same time,the composition of the gas generated by the anode of the battery with different voltage was analyzed by gas chromatography,which indicated that the gas was generated by the reduction reaction between the anode and the electrolyte.Combined with the results of high temperature gas generation measurement,XRD analysis and gas chromatography analysis,it is proved that the gas generation of lithium ion battery is mainly caused by the reaction of anode with the solution after oxidation and decomposition of SEI film under the condition of complete lithium removal,and the change of gas generation is related to the degree of lithium insertion.更多还原