储爱民,杨丽颖,刘厚才,伍先明

• 1:湖南科技大学机电工程学院
• 2:北京科技大学材料科学与工程学院
• 3:湖南科技大学机电工程学院
• 4:湖南科技大学机电工程学院 湖南湘潭411201

摘要(Abstract)：

为了改善La-Mg-Ni-Co系合金电极的循环稳定性,对铸态合金La0.75Mg0.25Ni3.5Co0.4在0.3MPa压力氩气保护下进行不同温度的退火(1123,1223和1323K),保温时间均为10h。研究了退火温度对合金的电化学性能的影响。X射线衍射(XRD)分析结果表明,铸态及1123K温度退火后合金主要由LaNi5,(La,Mg)2(Ni,Co)7相以及少量LaNi2相组成;退火温度为1223和1323K时,合金中LaNi2相消失,合金主要由LaNi5,(La,Mg)2(Ni,Co)7及(La,Mg)(Ni,Co)3相组成。随退火温度升高,最大放电容量从341.2mAh/g增加365.8mAh/g;循环稳定性得到改善,100次充放电循环后容量保持率从铸态合金的58.63%提高到1323K时的72.91%。

关键词(KeyWords)： 退火处理;La-Mg-Ni-Co系;贮氢合金;相结构;电化学性能

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 储爱民,杨丽颖,刘厚才,伍先明

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