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合金型锂离子电池负极材料由于容量高、安全性好而备受关注.采用磁控溅射法在铜箔上渡膜制备锡锌薄膜,经热处理后得到合金薄膜电极.薄膜热处理后,表面活性层形成Cu_3sn中间合金.合金薄膜是由尺寸在5 μm左右的合金颗粒构成,而合金颗粒则由更小的尺寸在50 nm左右微粒组成,该合金薄膜同时具有薄膜、中间合金和纳米结构材料的特征.合金薄膜电极具有较高的充放电容量、良好的循环性能和非常高的充放电效率.在0.01～1.0 V(vs.Li/Li~+)区间,电极循环200周后放电容量保持在300 mAh·g~(-1)以上,与第一次脱锂容量相比较,容量保持率高达91.9%,充放电效率大于98.0%.“,”Alloy negative materials for Li-ion batteries have been focused on because of high specific capacity and safety,which would be a promising material for next generation Li-ion batteries.In this work,alloy film anode has been prepared by depositing SnZn on Cu foil with a magnetron sputtering method,followed by heat-treatment.A Cu_3Sn intermetallic composite was formed after the heat-treatment.The SEM result showed that the alloy film was composed of alloy particles with the size of around 5 μm,and the alloy particle was composed of smaller particles with size of around 50 nm.The alloy film anode showed high charge-discharge capacity and columbic efficiency,and good cyclic stability.At potential of 0.01 ~ 1.0 V (vs.Li/Li~+),the discharge capacity remained over 300 mAh·g~(-1) after 200 cycles,and the columbic efficiency was over 98.0%.These results should be attributed to the unique structure of the alloy film anode composed of intermetallic composite,thin film and nano-sized active material.