|
Effect of Annealing Temperature on Structure and Electrochemical Properties of La-Y-Ni Alloy |
Author Name | Affiliation | E-mail | GUO Miao | GRIMAT Engineering Institute Co., Ltd., Beijing 101407, China | | YUAN Hui-Ping | GRIMAT Engineering Institute Co., Ltd., Beijing 101407, China | huiping.yuan1@gmail.com | LIU Yu-Ru | GRIMAT Engineering Institute Co., Ltd., Beijing 101407, China | | JIANG Li-Jun | GRIMAT Engineering Institute Co., Ltd., Beijing 101407, China | |
|
Abstract: The LaY2Ni9.7Mn0.5Al0.3 alloy was prepared by magnetic suspension induction melting method. It was annealed at different temperatures from 1 073 to 1 373 K. The effect of annealing temperature on the phase structure and the electrochemical properties was systematically investigated by X-ray diffraction (XRD), electron probe micro analysis (EPMA), and electrochemical measurements. It was proved that the heat treatment significantly improved the phase uniformity of the alloy. The content of the main phase Ce2Ni7-phase increased first and then decreased with the annealing temperature. At the same time, the maximum discharge capacity, high rate discharge-ability and the cyclic stability of the alloy electrodes all increased first and then decreased, which were consistent with the change of the content of Ce2Ni7 phase. The electrochemical pressure-content-temperature (P-C-T) curves of the alloy electrodes had two hydrogen desorption platforms, and their pressures both increased with the annealing temperature. When the annealing temperature was 1 273 K, the Ce2Ni7 phase content of the alloy was 86.53%(w/w), and the electrochemical properties were the best. The maximum discharge capacity reached to 386.80 mAh·g-1 (60 mA·g-1), the high rate discharge-ability at current density of 900 mA·g-1 (HRD900) was 89.45%, and the maximum capacity retention after 300 cycles (S300) was 72.18% (300 mA·g-1). |
Keywords: Ni-MH battery hydrogen storage alloy electrochemical properties heat treatment Ce2Ni7 type phase plateau pressure |
Hits: 1353 |
Download times: 595 |
GUO Miao,YUAN Hui-Ping,LIU Yu-Ru,JIANG Li-Jun.Effect of Annealing Temperature on Structure and Electrochemical Properties of La-Y-Ni Alloy[J].Chinese Journal of Inorganic Chemistry,2019,35(6):1041-1049. |
View Full Text View/Add Comment Download reader |
|
|
|
|
|