球磨和添加碳对SnCo0．9Y0．1合金显微结构和电性能的影响

摘要

采用固相烧结和球磨相结合的方法制备了SnCo0．9Y0.1合金，研究了球磨时间和添加碳对合金显微结构和电性能的影响。结果表明：SnCo0．9Y0.1合金的物相主要为CoSn和CoSn2；球磨后，物相不发生改变，但晶粒尺寸随着球磨时间的延长先减小后趋于稳定；添加碳后SnCo0．9Y0.1合金的物相也没改变，碳与合金形成物理混合物；SnCo0．9Y0.1合金的首次放电容量和首次充放电效率分别为300mA·h·g^-1和73．0％，经过25次循环后保持了首次放电容量的75．0％；球磨后，首次充放电容量和循环性能随着球磨时间延长先逐渐增加后趋于稳定，而首次充放电效率逐渐降低。碳的添加使SnCo0．9Y0.1合金的循环性能得到提高，25次循环后，保持了首次放电容量的85．9％。%SnCo0.9Y0.1 alloy was synthesized using solid-state sintering and ball milling, and effects of milling time and carbon addition on the microstructure and electrical properties were analyzed. The results show that theSnCo0.9Y0.1 alloy was mainly composed of CoSn and CoSn2, the phases did not change after milled, but the grain size decreased first and then tended to be stable with the prolongation of milling time. After adding carbon, phases of the alloy did not change, carbon and the alloy phase formed physical mixture. Initial discharge capacity and initial charge-discharge efficiency of the SnCo0.9Y0.1 alloy were 300 mA·h·g^-1 and 73.0 %, it remained above 75.0 % of the initial discharge capacity after 25 charge-discharge cycles. After milled, charge-discharge capacity and cycle performance increased first slowly and then tended to be stable, hut initial charge-discharge efficiency decreased gradually as the milling time increased. Adding carbon made cycle performance of SnCo0.9Y0.1 alloy better, and it remained above 85. 9% of the initial discharge capacity after 25 charge-discharge cycles.