洗涤和热处理对LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料结构和电化学充放电性能的影响（英文）

Effects of Washing and Heat-treatment on Structure and Electrochemical Charge/Discharge Property of LiNi_(0.8)Co_(0.15)Al_(0.05)O_2 Powder

用去离子水将原始的LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料进行洗涤并分别在不同温度下处理相同的时间,讨论了LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料结构、形貌以及电化学充放电性能的变化,同时探讨了洗涤和热处理对材料结构、电化学充放电性能以及倍率性能影响的机理。XRD分析表明:在洗涤和热处理之后,LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料的I(003)/I(104)比值以及晶胞体积均有变小;傅里叶红外光谱分析表明:在洗涤和热处理之后,LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料中形成了碳酸锂、镍化合物杂质及其相关变化。同时对洗涤和热处理前后LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料容量和倍率性能进行测试。容量测试结果表明:原始样品以及处理后样品在30圈循环之后容量保持率分别为88.87%、87.21%、85.43%和87.80%。

The effect of washing on electrochemical properties of Ni-rich layered cathode LiNi0.8Co0.15Al0.05O2 powder is widely known, but few literatures have reported thoroughly. Primitive LiNi0.8Co0.15A10.05O2 powders processed by deionized water and heat-treatment at different temperatures in a paralleling time was explored for the first time. Significant changes of structure, morphology and electrochemical charge/discharge property of the LiNi0.8Co0.15A10.05O2 cathode were detected comprehensively. Mechanism of washing and heat-treatment on the structure and electrochemical charge/discharge property and the rate performance were studied. XRD patterns show the 1（0o3）/10o4） value of LiNi0.8Co0.15A10.05O2 powders decreases and the volume turns smaller after being washed and heat-treated. FT-IR spec- tra confirm the existence of lithium carbonate, and nickel compounds and their relative changes in the LiNi0.8Co0.15Al0.0502 powders. The specific capacity and rate performance of the LiNi0.8Co0.15Al0.05O2powders were carried out before and after washing and heat-treatment. The capacities of primitive sample and treated samples remain 88.87%, 87.21%, 85.43% and 87.80% after 30 cycles, respectively.