Differences in the effects of Co and CoO on the performance of Ni(OH) 2 electrode in Ni/MH power battery
Differences in the effects of Co and CoO on the performance of Ni(OH) 2 electrode in Ni/MH power battery
复制标题
DOI：
10.1016/j.jpowsour.2010.06.065
复制
发表时间：
2011
影响因子：
9.2
通讯作者：
Yang Xia;Yifu Yang;Huixia Shao
中科院分区：
文献类型：
--
作者：
Yang Xia;Yifu Yang;Huixia Shao
研究了金属钴（Co）和一氧化钴（CoO）作为正极添加剂对Ni/MH动力电池电化学性能的影响。将商业Co和CoO在50°C下装入6 M KOH溶液中。通过观察钴材料在充电过程中的结构和形貌演变，研究了钴材料的氧化机理。当起始材料为CoO时，形成纯Co 3 O 4型相。当使用Co时，存在羟基氧化钴（CoOOH）相以及四氧化三钴（Co 3 O 4）相。在这两种情况下，电解质中的钴浓度在氧化过程中降低。最终产物取决于钴的溶解度和消耗四氢氧化钴[Co（OH）4]2−的反应动力学。在泡沫镍骨架和氢氧化镍[Ni（OH）2]颗粒之间形成了高度致密的CoOOH相，提高了Ni/MH动力电池的动力性能。Co 3 O 4对Ni（OH）2颗粒起到了良好的连接作用，提高了Ni/MH动力电池的电容性能。
The effects of metallic cobalt (Co) and cobalt monoxide (CoO), as additives in positive electrodes, on the electrochemical performance of nickel/metal hydride (Ni/MH) power batteries are studied. Commercial Co and CoO are charged at 50°C in 6M KOH solution. The oxidation mechanism of cobalt materials is investigated by observing structural and morphological evolutions during charging. A pure Co3O4-type phase is formed when the starting material is CoO. When Co is used, a cobalt oxyhydroxide (CoOOH) phase is present, together with a tricobalt tetroxide (Co3O4) phase. In both cases, the cobalt concentration in the electrolyte decreases during oxidation. The final product is dependent on the solubility of cobalt and the kinetics of the reaction that consumes cobalt tetrahydroxide [Co(OH)4]2−. The highly compact CoOOH phase, which works well between the nickel foam frame and nickel hydroxide [Ni(OH)2] particles, enhances the power performance of Ni/MH power battery. The Co3O4phase, which works well in connecting Ni(OH)2particles, improves the capacitive performance of Ni/MH power battery.