SYNTHESIS AND CHARACTERIZATION OF Li[Ni1/3Co1/3Mn1/3]O2 AS A CATHODE MATERIAL BY A HMTA-NITRATE COMBUSTION METHOD

Abstract

Li[Ni_1/3Co_1/3Mn_1/3]O₂ has attracted a great deal of interest in the investigation of cathode material for lithium ion batteries to replace the presently popular LiCoO₂ because the combination of Ni, Co, Mn can provide advantages such as stable cycling performance, good thermal stability and excellent rate capability [1-5]. The Li[Ni_1/3Co_1/3Mn_1/3]O₂ cathode materials were synthesized by a self-sustaining HMTA nitrate combustion method using starting materials of LiNO₃, Co(NO₃) 2.6H²O, Ni(NO₃) 2.6H₂O, Mn(NO₃)2.4H₂O, N_H4OH, C₆H₁₂N₄ and deionized water. The mixture of starting materials was quickly introduced in a muffle furnace, which was pre-heated to 500°C. The mixture was kept in the furnace at the set temperature for 15 min, during which time it decomposed in a smoldering (flameless) combustion process to yield a black, voluminous product of Li[Ni_1/3Co_1/3Mn_1/3]O₂. The product was allowed to cool, and subsequently subjected to calcinations at different temperatures for 12 hours. The morphology, structural and electrochemical behavior were characterized by means of SEM, X-ray diffraction analysis and electrochemical charge-discharge test. The cathode material synthesized by using this method showed reversible capacity of 184 mAhg^-1 in the voltage range of 3.0-4.9 V versus Li.