Acta Chimica Sinica ›› 2019, Vol. 77 ›› Issue (11): 1115-1128.DOI: 10.6023/A19070265 Previous Articles     Next Articles



李钊abc, 王忠abc*(), 班丽卿abc, 王建涛abc, 卢世刚abc   

  1. a 有研科技集团有限公司国家动力电池创新中心 北京 100088
    b 国联汽车动力电池研究院有限责任公司 北京 100088
    c 北京有色金属研究总院 北京 100088
  • 投稿日期:2019-07-16 发布日期:2019-10-09
  • 通讯作者: 王忠
  • 作者简介:李钊, 男, 1992年生, 硕士生. 2014年毕业于西北师范大学, 获得环境工程学士学位. 2014~2017年, 先后在锂电企业和中科院电工研究所从事锂离子电池材料和器件的研发工作. 2017年进入北京有色金属研究总院攻读材料科学与工程硕士学位.主要进行高性能富锂锰基正极材料的结构和界面研究|王忠, 男, 1967年生, 教授, 博士生导师. 2007年在北京科技大学获博士学位, 同年进入北京有色金属研究总院工作至今, 主要从事锂离子电池材料的结构和电化学性能的研究|卢世刚, 男, 1966年生, 教授, 博士生导师. 1993年在莫斯科大学获得化学博士学位.现任北京有色金属研究总院副总工程师, 国家动力电池创新中心首席专家, 承担新一代动力电池及材料的国家重点研发项目
  • 基金资助:

Recent Advances on Surface Modification of Li- and Mn-Rich Cathode Materials

Li Zhaoabc, Wang Zhongabc*(), Ban Liqinabc, Wang Jiantaoabc, Lu Shigangabc   

  1. a National Power Battery Innovation Center, GRINM Group Co., Ltd, Beijing 100088, China
    b China Automotive Battery Research Institute Co., Ltd., Beijing 100088, China
    c General Research Institute for Nonferrous Metals, Beijing 100088, China
  • Received:2019-07-16 Published:2019-10-09
  • Contact: Wang Zhong
  • Supported by:
    the National Key Research and Development Program of China(2018YFB0104400);the Natural Science Foundation-the Joint Foundation of China(U1764255)

With the rapid development of electric cars and energy storage power stations, there is an increasing demand for lithium ion batteries with high energy density. Li- and Mn-rich (LMR) cathode materials with large specific capacity (>250 mAh·g-1) are supposed to accomplish lithium ion batteries with high energy density (>350 Wh·kg-1). The high capacity performance of LMR cathode materials are resulted from the lattice oxygen redox reaction induced by the electrochemical activation of the Li2MnO3 phase. However, the activation of the Li2MnO3 phase and oxygen redox reaction lead to lattice oxygen release and structure transformation, which cause some serious problems such as low initial columbic efficiency, poor rate capability, voltage and capacity degradation after subsequent cycles. The oxygen release and structure transformation always start from the surface, indicating that the surface stability is significant to LMR cathode materials. In this paper, surface modifications such as surface coating, surface doping and surface chemical treatment are reviewed and the mechanism of three surface modification methods for LMR cathode materials are discussed in further. Surface coating is one of the most widely surface modification methods, which can suppress the electrode/electrolyte side reaction and reduce the transition metal dissolution. The effect of surface coating on improving electrochemical performance of LMR cathode materials is always determined by the characteristic of coating layer materials including non-active coating layer, electrochemical active coating layer, Li+ conductive coating layer and electronic conductive coating layer. Surface doping has shown to be an effective method in suppressing oxygen release and structural transformation. Surface chemical treatment has resulted in reducing irreversible capacity loss by activating Li2MnO3 phase. On this basis, surface integrated strategies combined several surface modified methods are introduced and discussed in recent years. The surface intergrated strategies not only enhance the structural stability and suppress electrode/electrolyte surface-interface reaction, but also have an effective role on mitigating structure transformation and lattice oxygen release. Finally, we wish that our review would provide research directions for surface modified strategies of LMR cathode materials in future.

Key words: Li- and Mn-rich cathode materials, surface coating, surface doping, surface chemical treatment, surface integrated strategies