化工学报 ›› 2021, Vol. 72 ›› Issue (12): 6380-6387.DOI: 10.11949/0438-1157.20211076

• 材料化学工程与纳米技术 • 上一篇    下一篇

高电压磷酸钴锂正极材料性能调控研究

崔声睿1(),董林涛1,金永成1(),向兰2()   

  1. 1.中国海洋大学材料科学与工程学院,山东 青岛 266100
    2.清华大学化学工程系,北京 100084
  • 收稿日期:2021-08-02 修回日期:2021-10-04 出版日期:2021-12-05 发布日期:2021-12-22
  • 通讯作者: 金永成,向兰
  • 作者简介:崔声睿(1996—),男,硕士研究生,csr@stu.ouc.edu.cn
  • 基金资助:
    国家重点研发计划项目(2017YFE0127600)

Studies on the performance of high voltage LiCoPO4 cathode materials

Shengrui CUI1(),Lintao DONG1,Yongcheng JIN1(),Lan XIANG2()   

  1. 1.School of Materials Science and Engineering, Ocean University of China, Qingdao 266100, Shandong, China
    2.Department of Chemical Engineering, Tsinghua University,Beijing 100084, China
  • Received:2021-08-02 Revised:2021-10-04 Online:2021-12-05 Published:2021-12-22
  • Contact: Yongcheng JIN,Lan XIANG

摘要:

高性能、高安全储能电池的迫切需求加速了橄榄石型高电压正极材料的研究步伐。为了改善高电压磷酸钴锂(LiCoPO4)的综合电化学性能,采用溶剂热法研究了溶剂比、过渡元素(Fe、Mn)单掺杂和双掺杂(掺杂元素总量占10%)对正极材料形貌、尺寸、反位缺陷和电化学性能的影响。结果表明,当溶剂比为2.3时,未掺杂LiCoPO4在0.1C下表现出163.1 mAh·g-1的最高理论比容量;双掺杂LiCo0.9Mn0.05Fe0.05PO4正极材料具有突出的循环性能,在0.5C电流密度下,循环100圈后的容量保持率为78.9%,循环稳定性得到明显改善。

关键词: 磷酸钴锂, 溶剂热法, 混合溶剂, 元素掺杂

Abstract:

The urgent need for high-performance, high-safety energy storage batteries has accelerated the pace of research on olivine-type high-voltage cathode materials. Lithium cobalt phosphate (LiCoPO4) with different Fe and Mn doping contents (10% of the total doping elements) was synthesized by using solvothermal method with diethylene glycol (DEG) and H2O as mixed solvent. The effects of the solvent ratio and element doping contents on the morphology, size, antisite defects and electrochemical properties of as-prepared cathode materials were discussed. The results show that LiCoPO4 demonstrated the highest discharge capacity of 163.1 mAh·g-1 when the solvent ratio of 2.3 was used and LiCo0.9Mn0.05Fe0.05PO4 cathode material prepared under the solvent ratio of 2.3 had outstanding cycling performance and the capacity retention after 100 cycles was 78.9% at 0.5C.

Key words: lithium cobalt phosphate, solvothermal method, mixed solvent, element doping

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