Transactions of Nonferrous Metals Society of China The Chinese Journal of Nonferrous Metals

您目前所在的位置:首页 - 期刊简介 - 详细页面

中国有色金属学报(英文版)

Transactions of Nonferrous Metals Society of China

Vol. 25    No. 2    February 2015

[PDF Download]    [Flash Online]    

    

Effect of Sn substitution for Co on microstructure and electrochemical performance of AB5 type La0.7Mg0.3Al0.3Mn0.4Co0.5-xSnxNi3.8 (x=0-0.5) alloys
Julio Cesar Serafim CASINI1,2, Zai-ping GUO1, Hua Kun LIU1, Eliner Affonso FERREIRA2, Rubens Nunes FARIA2, Hidetoshi TAKIISHI2

1. Institute for Semiconducting and Electronic Materials, University of Wollongong, NSW 2522, Australia;
2. Materials Science and Technology Center, Nuclear and Energy Research Institute,
University of S?o Paulo, SP 05508-900, Brazil

Abstract:The effects of substitution of Sn for Co on the microstructure, hydrogen storage and electrochemical discharge capacity of La0.7Mg0.3Al0.3Mn0.4Co0.5-xSnxNi3.8 (x=0, 0.1, 0.2, 0.3 and 0.5) alloys were investigated using X-ray diffraction (XRD), pressure composition isotherm (PCT) and electrochemical discharge cycle. XRD, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) tests showed that all of alloys are mainly composed of LaNi5 and MgNi2 phases, but when increasing the content of Sn in alloys, the LaNiSn phase appears and microstructure is refined. The PCT showed that increasing substitution of Sn for Co results in decrease of the maximum hydrogen storage capacity from 1.48% (x=0) to 0.85% (x=0.5). The electrochemical tests indicated that the maximum discharge capacity decreases from 337.1 mA?h/g (x=0) to 239.8 mA?h/g (x=0.5); however, the discharge capacity retention at the 100th cycle increases from 70.2% (x=0) to 78.0% (x=0.5).

 

Key words: hydrogen storage alloys; microstructure; Ni-MH batteries; Sn; Co; substitution

ISSN 1004-0609
CN 43-1238/TG
CODEN: ZYJXFK

ISSN 1003-6326
CN 43-1239/TG
CODEN: TNMCEW

主管:中国科学技术协会 主办:中国有色金属学会 承办:中南大学
湘ICP备09001153号 版权所有:《中国有色金属学报》编辑部
------------------------------------------------------------------------------------------
地 址:湖南省长沙市岳麓山中南大学内 邮编:410083
电 话:0731-88876765,88877197,88830410   传真:0731-88877197   电子邮箱:f_ysxb@163.com