储能科学与技术 ›› 2019, Vol. 8 ›› Issue (6): 1165-1170.doi: 10.12028/j.issn.2095-4239.2019.0089

• 研究开发 • 上一篇    下一篇

高电压锂离子电池高温浮充性能影响因素分析与改善

孔令丽, 张克军, 夏晓萌, 蔡嘉兴, 孙杰, 杨玉秋   

  1. 天津力神电池股份有限公司, 天津 300384
  • 收稿日期:2019-05-16 修回日期:2019-06-10 出版日期:2019-11-01 发布日期:2019-07-31
  • 通讯作者: 张克军,博士,工程师,E-mail:zhangkejun@lishen.com.cn。
  • 作者简介:孔令丽(1978-),女,高级工程师,研究方向为锂离子电池,E-mail:konglingli@lishen.com.cn

Analysis and improvement of high temperature floating charge performance for high voltage lithium ion batteries

KONG Lily, ZHANG Kejun, XIA Xiaomeng, CAI Jiaxing, SUN Jie, YANG Yuqiu   

  1. Tianjin Lishen Battery Joint-Stock Co., LTD., Tianjin 300384, China
  • Received:2019-05-16 Revised:2019-06-10 Online:2019-11-01 Published:2019-07-31

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摘要： 为研究高电压体系锂离子电池浮充性能的影响因素，对浮充失效电池的产气成分、正负极材料的结构变化、金属溶出情况、隔膜形貌及Gurley值变化等进行了深入分析研究，结果表明：电池在长时间高温浮充过程中，正极材料发生相变，金属元素溶出，同时释放O2造成电解液的氧化分解；高温高电压状态下负极SEI膜也会破坏，并发生不断的重整及修复反应，这些反应产物沉积到负极表面及隔膜孔隙内，导致靠近负极侧的隔膜孔隙堵塞甚至贯穿，即引起正负极微短路，释放出大量气体。通过提高正极材料的结构稳定性、优化电解液形成稳定的CEI和SEI，改善增加隔膜的穿刺强度都能明显改善电池的高温浮充性能。

关键词: 锂离子电池, 高电压, 高温, 浮充性能, 鼓胀

Abstract: In order to study the influence factors of floating charge performance of lithium ion battery in high-voltage system, the gas-producing composition, structure change of cathode and anode materials, metal dissolution, separator morphology and Gurley value change of floating charge failure battery were deeply analyzed. The results show that:In the process of floating charge at high temperature for a long time, the cathode material will undergo phase transformation, and the metal elements will be dissolved. Meanwhile, O2 will be released to cause the oxidation and decomposition of the electrolyte. Under the condition of high temperature and high voltage, the SEI film on anode surface will also be destroyed, and continuous reforming and repair reactions will occur. These reaction products are deposited on the surface of anode and in the separator pores, resulting in the blockage and even penetration of separator pores near the anode electrode side. In other words, the cathode and anode micro-short circuit will be caused, and a large amount of gas will be released. By improving structure stability of cathode materials, optimizing electrolyte and increasing the puncture strength of separator, the high-temperature floating charge performance of the battery can be significantly improved.

Key words: lithium ion battery, high voltage, high temperature, float charge, swelling

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