An electrochemical study of new La1-xCexY2Ni9 (0 ≤ x ≤ 1) hydrogen storage alloys

New ternary yttrium-based alloys belonging to the R-Y-Ni system (R= La. Ce), with general formula La1-xCexY2Ni9 (0 less than or equal to x less than or equal to 1) have been synthesized, and their hydrogen absorption -desorption properties have been investigated through solid gas and electrochemical measurements. The thermodynamic data determined here (hydrogen absorption capacities and hydride formation pressures) are consistent with their application as negative electrode materials in alkaline medium. The electrochemical study shows promising results for La-rich compositions in terms of discharge capacity. rate capability and cycling behavior. The influence of cerium substitution on the negative electrode behavior is discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.