Improved Electrochemical Cyclic Performances of Spinel LiMn2O4 by Coating with Lanthanum Phosphate
Yiqi Cui, Chengyi Zhu, Rui Huang, Jiaming Liu, Yannan Zhang
Abstract
LiMn 2 O 4 is regarded as a promising positive material candidate for contemporary lithium-ion batteries (LIBs) in terms of high safety, low cost, and environmental benignity. However, the spinel LiMn2O4 electrodes suffer from rapid capacity fades during lithiation and delithiation at high temperatures. Herein, we describe a simple sol-gel reaction method to modify the surface of LiMn2O4 materials and fill the gaps between particles by LaPO 4 to improve its electrochemical performance and utilization in the room and high temperature. As a result, the as-prepared LiMn 2 O 4 @ LaPO 4 electrode delivers excellent reversible capacity retention of 81.3% after 200 cycles at 1 C rate and exhibits a remarkable capacity of 74.9 mAh g -1 at 10 C rate. Moreover, Mn dissolution measurement reveals that LaPO 4 coating can effectively reduce the manganese dissolution in electrolytes at high temperatures. This general surface-modification strategy will have implications in practical applications for long-life lithium-ion batteries.