的相結(jié)構與高溫電化學性能
(浙江大學 材料科學與工程系， 杭州 310027)
摘 要: 針對電動車用大型動力Ni/MH電池工作溫度較高的特點，系統(tǒng)地研究了Mn部分取代Ni對貯氫合金RENi3.95-xMnx Co0.75Al0.3相結(jié)構和高溫（60 ℃）電化學性能的影響。結(jié)果表明，RENi3.95-xMnx Co0.75Al0.3(x=0～0.6)合金具有單一的CaCu5型LaNi5相結(jié)構，其晶胞體積隨Mn含量的增加而增大；Mn的加入能有效地改善合金的高溫活化性能和放電容量，但會加快合金的循環(huán)容量衰退，降低充放電循環(huán)穩(wěn)定性；Mn含量在x=0.3～0.5時，合金具有較好的高溫高倍率放電性能。
關鍵字: 貯氫電極合金； Mn含量； 相結(jié)構； 電化學性能
of RENi3.95-xMnx Co0.75Al0.3( x =0～0.6) hydrogen
storage alloys at higher
（Department of Materials Science and Engineering,
Zhejiang University, Hangzhou 310027, P.R.China）
Abstract:In view of higher working temperature of large-size Ni/MH battery used as EV battery, the effects of various content of Mn on the phase structure and electrochemical properties of RENi3.95-xMnx Co0.75Al0.3(x=0～0.6) hydrogen storage alloys at higher temperature (60 ℃) have been investigated systematically. The results show that by the addition of Mn, the alloys still have single CaCu5 type LaNi5 phase structure, but the lattice volume increased; when Mn is added, the activation behavior and discharge capacity of the alloys are improved, whereas the cycling stability deteriorated; high-rate-dischargeability is better when x =0.3～0.5.
Key words: hydrogen storage alloy； Mn content； phase structure； electrochemical performance
