Influence of annealing temperature on electrochemical properties of rapidly quenched LPC(NiAlMn)4.25 Co0.75 hydrogen storage alloy electrodes

• 作者: 唐定骧 涂铭旌 王金国 郑群 陈云贵 陶明大
• 来源期刊: 中国有色金属学会会刊（英文版）
• 学科: 工学
• 关键词: LPC mischmetal hydrogen storage alloys electrochemical properties recrystallization
• 年，卷（期）: 2004,（6）
• 页码范围: 1129-1133
• 页数: 5页
• 分类号: TG139.7
• 语种: 英文

摘要

The influence of annealing temperature on the electrochemical properties and structure of the rapidly quenched LPC(NiAlMn)4.25 Co0.75 hydrogen storage alloys was investigated, in which LPC represents the abbreviation of Nd-free La-Ce-Pr mischmetal after the extraction of most of Ce and Nd. After the annealing treatment between 700 - 900 ℃ for rapidly quenched alloys, their discharge capacity becomes larger and the P-C-T plateau tends to be flatter and lower. The alloy annealed at 700 ℃ has the highest discharge capacity and flattest plateau. The analyses by X-ray diffraction (XRD), different thermal analysis(DTA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicate that the microstructure reversion and recrystallization occur during the heating, and their feature temperatures are 477 ℃ and 696 ℃ respectively. The annealing treatments make cell volume increase, dislocations and strain decrease, and the distribution of alloy composition become homogeneous.