Preliminary studies of biominerals-coated spinel LiMn₂ O ₄ as a cathode material on electrochemical performances for Li-ion rechargeable batteries

Lithium manganese oxide (LiMn₂O₄) is an inexpensive and pollution-free cathode material for Li-ion rechargeable batteries. In this study, spinel LiMn₂O₄ cathode material was coated with biomineral powders by the mechano-chemical method. In the course of the material synthesis, citric acid and acryl amide were added to serve as a complexing agent and a gelling agent, respectively, followed by a calcination process at 700 °C for 6 h in a high-purity argon atmosphere. The spinel LiMn ₂O₄ and biominerals-coated spinel LiMn₂O ₄ cathode materials were, from diverse viewpoints, characterized by x-ray diffraction, field emission-scanning electron microscopy, Fourier transform infrared spectroscopy and the electrochemical cycling method to understand the mechanism of improvements in electrochemical performances. We suggest that the biominerals-coated spinel LiMn₂O₄ is a good candidate as a low cost and environmentally friendly cathode material showing the enlarged capacity characteristic of Li-ion rechargeable batteries.