热解碳包覆CoSb3作为锂离子电池负极材料的研究

CoSb3合金具有较高的电化学嵌放锂容量.为缓解充放电过程中体积变化引起的容量衰退,制备了热解碳包覆CoSb3合金粉末负极材料,并对其电化学充放电性能进行了研究.实验结果表明,热解碳包覆CoSb3负极材料的电化学性能虽然尚不能满足实际应用要求,但与纯CoSb3合金负极材料相比,首次可逆容量和循环稳定性都有明显的提高.进一步降低CoSb3合金的粉末粒度,优化热解碳对合金粉末的包覆完整性,可进一步改善热解碳包覆CoSb3负极材料的电化学性能.

Study on Pyrolytic Coke Coated CoSb3 as an Anode Material for Lithium-Ion Batteries

Intermetallic compound CoSb_3,with a high electrochemical capacity,is a potential anode materialfor lithium-ion batteries.To reduce the capacity fading caused by the volume change of the compound during cycling,a composite of CoSb_3 powder coated with pyrolytic coke was prepared and studied as an anode material for lithium-ionbatteries.It was shown that both reversible capacity and cycling stability of the coke coated CoSb_3 composite havebeen significantly improved in comparison with CoSb_3 compound,although the present electrochemical performance ofthe composite cannot meet the requirements of practical application of lithium-ion batteries.However,it is suggestedthat the electrochemical properties of the coke coated CoSb_3 composite could be further improved by decreasing theparticle sizes of CoSb_3 powder and enhancing the coating of pyrolytic coke around CoSb_3 powder.