Improvement of Cycling Stability of LiMn2O4 Cathode by Al2O3 Surface Coating for Li-Ion Batteries

H. Şahann, S. Veziroğlu and Ş. Patat Department of Chemistry, Faculty of Science, Erciyes University, 38039 Kayseri, Turkey

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The effect of the Al2O3 coating on the charge-discharge cycling performance of spinel powder (LiMn2O4) was investigated in the range of 3.5-4.5 V at 1C. The Al2O3 coating on the surface of the spinel powder was carried out using the solution method, followed by 500°C for 6 h in air. Powder X-ray diffraction pattern of the Al2O3-coated spinel LiMn2O4 showed that the Al2O3 coating medium was not incorporated in the spinel bulk structure. Scanning electron microscopy results showed that the Al2O3 coating particles were homogeneously distributed on the surface of LiMn2O4 powder particles. The Al2O3-coated LiMn2O4 retained 92.3% of its original capacity after 30 cycles, showing much better cycle ability than the bare lithium manganese oxide. The improvement of electrochemical performance is attributed to suppression of Mn2+ dissolution into electrolyte via Al2O3 layer.

DOI: 10.12693/APhysPolA.123.368 PACS numbers: 88.80.ff