The layered oxides LiMO2 (M = Co, Ni, V), have been extensively studied as potential cathode materials for lithium secondary batteries with high energy density [1-4]. Although LiCoCb has been used as cathode material for lithium ion batteries, LiNiO2 became more attractive because of its lower cost, higher capacity, better reversibility, lower maximum charge voltage and higher electrolyte stability [5-7]. But stoichiometric LiNiO? is difficult to synthesize under mild conditions, because the high temperature treatment of LiNiO2 leads to a decomposition from LiNiO2 to Lii_.YNii+.vO2 (.v>0), which has a partially disordered cation distribution at the lithium sites. The structural and electrochemical properties of LiNiO2 strongly depend upon the conditions of synthesis [8,9]. Therefore, it is necessary to synthesize LiNiO2 by proper processing methods. Several techniques have been proposed to synthesize electroactive LiNiO2 [7, 10, 11]. LiNiO2 powders have usually been prepared by solid-state reaction followed by grinding and calcination of hydroxides, carbonates or nitrates such as LiOH-H20, U2CO3, L1NO3, Ni(OH)2 and NiCO3 [10,11]. But this method has several disadvantages: inhomogeneity, irregular morphology, larger particle size and broader particle size distribution. It is believed in the Li.vMC>2 application that good cry stall inity, homogeneity and uniform particle morphology with a narrow size distribution are important parameters to achieve higher electrode activity. A sol-gel method, one of the solution methods, has recently been developed to enhance the physicochemical properties of the oxide powder systems [12-14]. Synthesis of LiNiO2 powders by this method using polyvinyl butyral (PVB) as a chelating agent has not been reported so far.
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