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

Abstract

LiMn 2 O 4 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 LiMn 2 O 4 spinel synthesized by solid state. LiMn 2 O 4 synthesized by glycolic acid-assisted sol-gel method improves the cycling stability of electrode. The capacity retention of sol-gelsynthesized LiMn 2 O 4 was about 90• after 100 cycles between 3.0 and 4.4 V at room temperature. The electrochemical performance of the LiMn 2 O 4 (sol-gel) and LiMn 2 O 4 (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 LiMn 2 O 4 (sol-gel) could effectively suppress the LiMn 2 O 4 dissolving of into electrolyte and resulted in a better stability.