机械球磨Mg2Ni0．95Sn0．05＋x％Ni非晶复合物的微结构和电化学性能

Microstructure and Electrochemical Properties of Amorphous Composites of Ball-Milled Mg2Ni0.95Sn0.05+x wt% Ni

摘要:

用机械球磨法合成了Mg2Ni0．95Sn0．05＋x％Ni（质量分数，x=25，50，75，100，125）非晶复合物，研究了其微结构和电化学性能。微结构分析表明，不添加Ni粉的Mg2Ni0．95Sn0．05合金经100h球磨后仍然难以形成非晶结构，加入镍粉有助于非晶结构的形成。电化学研究表明，铸态最大放电容量仅为16mAh／g，球磨100h后容量改善不明显；加入Ni粉球磨后，容量大幅上升，随着Ni添加量的增加，复合物最大放电容量先增后减，在x=75时达到最大值625.6mAh／g。把x=50时的复合物，延长球磨时间t，复合物最大放电容量提高，当t=200h时达到670mAh／g。

Abstract:

The amorphous Mg2Ni0.95Sn0.05 + x wt% Ni(x=25,50,75,100,125)composites were synthesized by mechanical ball-milled.The microstructure and electrochemical properties of the composites were investigated.The microstructure analysis indicates that it is difficult to form amorphous structure when the Mg2Ni0.95Sn0.05 alloy is ball-milled without addition of Ni powder.The addition of Ni does favor the formation of amorphous structure.The electrochemical analysis indicates that the discharge capacity of as-cast Mg2Ni0.95Sn0.05 alloy is only 16 mAh/g and almost has no changes after 100 h ball milling.When the alloy with addition of Ni powder was milled its discharge capacity was greatly increased.With increasing of Ni content x,the discharge capacity increased first and then decreased,and reached the maximum of 625.6 mAh/g at x=75.For x=50 composite,the discharge capacity increased after increasing of the ball-milling time,and the maximal discharge capacity increased to 670 mAh/g at t=200 h.