球磨对Sn-Co合金结构和电化学性能的影响研究

Effects of Ball Milling on Microstructure and Electrochemical Properties of Sn-Co alloy

以金属Sn、Co粉末为原料,采用先固相烧结再球磨的方法制备了CoSn2/CoSn和Co3Sn2合金,考察了不同原料配比条件下球磨对合金形貌、结构和电化学性能的影响。结果表明,按照目标产物配比可分别获得单相CoSn2、CoSn和Co3Sn2合金,且合金经过球磨后晶粒细化;球磨可提高Sn-Co合金的电化学性能,对CoSn2的循环性能提升效果显著,经过25次循环后的容量保持率提升了16.5%;对CoSn和Co3Sn2的容量和充放电效率提升效果显著,CoSn的首次放电容量和充放电效率分别提升了167 mAh/g和16.6%,Co3Sn2分别提升了151mAh/g和21.5%。

Sn-Co alloys,namely CoSn2,CoSn and Co3Sn2,were synthesized by solid-state reaction and ball milling from metal Sn and Co powder.The effects of ball milling on the morphology,microstructure and electrochemical properties under different Sn/Co ratios were investigated.The XRD results indicate that the CoSn2,CoSn or Co3Sn2 single phase alloy can be obtained according to the target product ratio and the grain refining appears in alloys after ball milling.The electrical performances show that the electrochemical property of Sn-Co alloys can be improved by ball milling;the circulatory property of CoSn2 increases remarkably and the capacity-keeping rate increases by 16.5% after 25 times cycles;the capacity and the charging and discharging efficiency of CoSn and Co3Sn2 increases remarkably.The first discharging capacity and the efficiency of the charging and discharging of CoSn are improved by 167 mAh/g and 16.6%,respectively,and those of Co3Sn2 have been improved by 151mAh/g and 21.5%.