Summary: | Novel, single phase LiMn0.3Co0.3Ni0.3Cr0.1O2 materials are prepared using a sol-gel method without the use of chelating agents. The XRD results showed that the materials are pure and isostructural with α-NaFeO2. The optimization of thermal annealing was done to investigate the best calcination condition for good electrochemical behaviour. The compounds annealed at different temperatures and different annealing times showed variations in discharge profiles and capacities. The compound annealed at 900 °C for 48 h exhibits the highest capacity of 167 mAhg-1 over the voltage range of 2.5 to 4.2 V. Other heat-treated samples also exhibit good electrochemical performance approaching that of LiCoO2. XPS studies of the material shows the existence of Co3+, Co2+, Ni2+, Mn2+, Mn3+, Mn4+, Cr3+ and Cr6+ in the sample material and subsequently, charge-discharge mechanisms are identified. © 2013 by ESG.
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