Enhancement of the electrochemical properties of LiMn2O4 by glycolic acid-assisted sol-gel method

Abstract

LiMn2O4 spinel cathode was synthesized by the sol–gel method by using glycolic acid as a chelating agent. The sample exhibited a pure cubic spinel structure without any impurities in the X-ray diffraction (XRD) patterns. The result of the electrochemical performances on the sample compared to those of electrodes based on LiMn2O4 spinel synthesized by solid state. LiMn2O4 synthesized by glycolic acid-assisted sol–gel method improves the cycling stability of electrode. The capacity retention of sol–gel-synthesized LiMn2O4 was about 90• after 100 cycles between 3.0 and 4.4 V at room temperature. The electrochemical performance of the LiMn2O4 (sol–gel) and LiMn2O4 (solid state) were investigated under 40• between 3.0 and 4.4 V. XRD results of the cathode material after 50 cycles at 40• revealed that LiMn2O4 (sol–gel) could effectively suppress the LiMn2O4 dissolving of into electrolyte and resulted in a better stability.