Mixed lithium ion and electron conducting LiAlPO3.93F1.07-coated LiCoO2 cathode with improved electrochemical performance

作者:Shen, Bin; Liu, Qianqian; Wang, Liguang; Yin, Geping*; Zuo, Pengjian; Ma, Yulin; Cheng, Xinqun; Du, Chunyu; Gao, Yunzhi
来源:Electrochemistry Communications, 2017, 83: 106-109.
DOI:10.1016/j.elecom.2017.09.002

摘要

LiCoO2 (LCO) has been functionally modified by mixed lithium ion and electron conducting LiAlPO3.93F1.07 (LAPF) for the first time. Due to the unique coating layer with accepted Li-ion diffusion rate and electronic conductivity, the LAPF-coated LCO exhibits outstanding rate capability and cycle stability in the voltage range of 2.75-4.55 V. This material delivered a specific capacity of 206 mAh.g(-1) up to 0.5C rate and the capacity retention was 91.7% after 50 cycles, which is a remarkable improvement comparing with uncoated LCO (34.8%). It also exhibited superior rate capability with a discharge capacity of 161.4 mAh.g(-1) at 4C. The functionalized LAPF coating technique is an efficient approach to improve the electrochemical performance of LCO and can also be referred for other layered oxide cathode materials.