%0 Journal Article
%T Phase Structure and Electrochemical Properties of La--Mg--Ni System AB3 Type Hydrogen Storage Electrode Alloys<br>La-Mg-Ni系AB3型贮氢电极合金的相结构与电化学性能
%A LIAO Bin
%A LEI Yongquan
%A LU Guanglie
%A CHEN Lixin
%A GE Hongwei
%A PAN Hongge
%A <br>廖 彬
%A 雷永泉
%A 吕光烈
%A 陈立新
%A 葛红卫
%A 潘洪革
%J 金属学报
%D 2005
%I 
%X XRD Rietveld analysis shows that LaxMg3-xNi9 (x=1.0---2.3) alloys consist of a main phase with hexagonal PuNi3-type structure and a few impurity phases (mainly LaNi5 and MgNi2, increasing x leads to an increase in both the lattice parameters and the unit cell volume of the main phase. The hydride of the alloys preserves the PuNi3 type structure, but shows a large unit cell volume expansion. The electrochemical measures indicate that the desorption plateau pressure Prm of the alloys decreases noticeably as x increases, while the maximum discharge capacity Cmax increases from 88.3 (x=1.0) to 397.5 (x=2.0), and then decreases to 230 mA.h/g (x=2.3). For the alloys with Cmax>348 mA.h/g (x=1.7-2.2), the high-rate dischargeability (HRD) of the electrodes at i=400-1200 mA/g decreases with increaseing x. The slower decrease of HRD is mainly attributed to the decrease of eletrocatalytic activity due to the charge--transfer reaction, and the more rapid decrease of HRD of the alloys with $x>$2.0 is related to the lower hydrogen diffusion rate in the bulk of alloy. The rate of capacity retention (S100) of the alloys after 100 charge/ discharge cycles is around 55.7%-62.9%, the rather fast cycling capacity degradation is mainly due to the corrosion of La and Mg and the large unit cell volume expansion in the hydride phase.
%K La-Mg-Ni hydrogen storage alloy
%K PuNi3-type structure
%K PCT curve
%K electrochemical property
%K hydrogen diffusion rate<br>La-Mg-Ni型贮氢合金
%K PuNi3型结构
%K PCT曲线
%K 电化学性能
%K 氢扩散速率
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=5B3AB970F71A803DEACDC0559115BFCF0A068CD97DD29835&cid=AB188D3B70B071C57EB64E395D864ECE&jid=B061E1135F1CBDEE96CD96C109FEAD65&aid=3761899C873EF401&yid=2DD7160C83D0ACED&vid=2001E0D53B7B80EC&iid=CA4FD0336C81A37A&sid=2001E0D53B7B80EC&eid=B6DA1AC076E37400&journal_id=0412-1961&journal_name=金属学报&referenced_num=11&reference_num=24