表面包覆Co(OH)_2和Er(OH)_3的球形Ni(OH)_2的高温性能

High-temperature performances of spherical Ni(OH)_2 coated with Co(OH)_2 and Er(OH)_3

利用化学沉淀法在球形Ni(OH)2表面复合包覆Co(OH)2和Er(OH)3,利用XRD、SEM和恒电流充放电技术测试其结构、表面微观形貌和充放电性能。研究不同包覆量对其常温和高温性能的影响,确定最佳包覆比为1%(质量分数)。循环伏安测试结果表明:包覆Er(OH)3的球形Ni(OH)2可以有效提高镍正极在高温环境下的析氧副反应电位,从而抑制析氧副反应的发生,最终提高镍电极在高温环境下的充电效率和活性物质利用率。

The spherical nickel hydroxide coated by Co（OH）2 and Er（OH）3 was prepared by chemical precipitation.The structure,surface microstructures and charge-discharge properties were analyzed by X-ray diffractometry,scanning electron microscopy and galvanostatic charge-discharge cycling technology.The optimum coating amount of was determined to be 1%（mass fraction） by comparing different amounts of coating on their electrochemical properties at room temperature and high temperature.The cyclic voltammetry results indicate that the coating of the erbium hydroxide on the spherical nickel hydroxide can enhance the potential of oxygen evolution at high temperature,and thus inhibit the occurrence of oxygen evolution.Simultaneously,the charge efficiency and the active material utilization of nickel hydroxide electrode are increase at high temperature.