Article ID Journal Published Year Pages File Type
7738782 Journal of Power Sources 2014 10 Pages PDF
Abstract
The effects of the synthesis temperature, the synthesis time and the nature of the transition-metal hydroxide precursors on the physical and electrochemical properties of Li(Ni1−x−yCoxMny)O2 synthesized using solid-state reactions are studied. Higher synthesis temperature results in larger primary and secondary particle sizes, a lower tap density and a broader secondary particle size distribution. Increase in reaction time improves the crystallinity and the cyclability. A smaller primary particle size of the precursor leads to a larger primary particle size of Li(Ni1−x−yCoxMny)O2. Li(Ni1−x−yCoxMny)O2 with a better crystallinity, a well-defined layered structure and a better cation ordering exhibits a higher capacity, a better cycling performance and rate capability. The optimized synthesis conditions for precursors NCMOH111-α and NCMOH424-a is 950 °C for 12 h and 950 °C for 9 h, respectively. NCM111-α-950-12h delivers a discharge capacity of 165.5 mAh g−1 during the initial cycle at a rate of 0.1C with a columbic efficiency of 87%, a 3C rate capability of 91.25% and a 1C capacity retention rate of 98.25% after 40 cycles.
Related Topics
Physical Sciences and Engineering Chemistry Electrochemistry
Authors
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