Mechanochemical Synthesis and Electrochemical Properties of LiMn ₂ O ₄

Abstract

Spinel LiMn 2 O 4 as a cathode material for lithium secondary batteries has been synthesized by a mechanochemical process, and its electrochemical properties have been characterized. Highly disordered nanocrystalline LiMn 2 O 4 powders have been prepared by the mechanochemical processing of Li 2 O and MnO 2 powder mixtures for 24 h. Electrochemical characterization of mechanochemically processed powder has shown that the intercalation of Li + takes place with an initial capacity of 167 mA·h/g in the 2.5–4.3 V range and has better capacity retention as compared to the well‐ordered crystalline LiMn 2 O 4 powders. The better capacity retention of the mechanochemically processed LiMn 2 O 4 powder may be attributed to the highly disordered structure that could accommodate the Jahn–Teller distortion of the spinel structure during Li + intercalation around the 3 V region.