Electrochemical Properties of Boron-Doped LiMn₂O₄ Nanoparticles Covered with Glass Material Prepared by High-Temperature Flame Spray Pyrolysis

摘要

Lithium boron oxide (LBO) glass-modified LiMn2O4 nanoparticles are prepared by high-temperatureflame spray pyrolysis. The mean sizes of the pure and 5 wt% glass-modified LiMn2O4 powders are 125and 175 nm, respectively. In addition, their mean crystallite sizes are 62 and 82 nm, respectively. At ahigh operating temperature of 60C and a current density of 1 C, the discharge capacity of the pure-1 LiMn2O4 powders decreases from 143 to 93 mAh g after 100 cycles, with the capacity retention at65% of the initial capacity. However, the discharge capacity of the 5 wt% glass-modified LiMn2O4-1 powders decreases from 123 to 106 mAh g after 100 cycles, with the capacity retention at 86% of theinitial capacity. The LBO glass material covering the LiMn2O4 powders improves theirelectrochemical properties by decreasing their reactivity with acidic electrolytes. Moreover, the highcrystallinity and stabilization effect of boron doping in the spinel structure improves theelectrochemical properties of the LBO glass-modified LiMn2O4 powders.