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针对锡负极材料充放电过程中的体积效应,综合采用组分改性与结构改性的研究方法,合成Cu0.85Sn015合金负极材料,研究Cu的掺入对Sn电化学稳定性的影响,同时基于优化改性的Cu0.85Sn0.15合金开展核壳结构设计,研究最佳核壳结构构造工艺.结果表明,掺入Cu能在一定程度上改善Sn的循环稳定性,Cu0.85Sn0.15样品的容量在60次循环后趋于稳定,库伦效率较高;核壳结构处理能大幅提升Cu0.85 Sn0.15合金负极材料的循环稳定性,采用球形改性天然石墨作为内核的G@Cu00.Sn0.15@C负极材料首次放电比容量接近800 mAh/g,充电比容量最大值超过了500 mAh/g,100次容量保持率大于85％.核壳结构能将Cu0.85Sn0.15合金的体积效应控制在“囚笼”式结构内,利于材料容量的发挥及循环稳定性的提升.核壳结构的可控制备对实现锡基合金负极材料的产业化具有重要的作用.“,”Based on the component and structure modifications,Cu0.85Sn0.155 alloy anode material was synthesized,and the preparation technology of the core-shell structure was studied,to solve the volume expansion during the charge and discharge process of Sn-based anode materials.The results showed that,the addition of Cu could to some extent improve the cyclic stability.The capacity of the Cu0.85Sn0.1.5 sample became stable after 60 cycles,with high coulomb efficiency.The core-shell structure could dramatically improve the cyclic stability of the Cu0.8.5 Sn0.15 alloy,for G@Cu0.85Sn0.15@C whose core was modificated by natural spherical graphite,the initial specific discharge capacity was nearly 800 mAh/g,the max charge capacity was higher than 500 mAh/g,and the capacity retention of 100 cycles was higher than 85％.The volume expansion can be contorlled within the “cage structure” by the core-shell structure,which benefits for the capacity performance and the improvement of the cyclic stability.The controllable preparation of the core-shell structure is important for the commercialization of Snbased anode materials.