摘要
在惰性气氛保护下,采用“梯度共晶”-络合共沉积方法,在球形Ni（OH）2表面包覆不同含量的Co（OH）2。利用X射线衍射、扫描电镜和恒电流充放电技术测试其相结构、表面微观形貌和充放电性能。研究结果表明：镶嵌Co（OH）2包覆层的球形Ni（OH）2具有良好的放电容量和大电流充放电性能。倍率放电性能与包覆Co（OH）2的量有一定的关系。在0.8C充电/0.4C放电条件下,包覆层最佳含Co（OH）2量为0.8%;而在1C充放电、2C充电/1C放电和3C充放电条件下,包覆层含Co（OH）2量最佳范围为2%-3.6%。表面包覆价态稳定Co（OH）2是改善氢氧化镍电极大电流充放电性能的一条有效途径。
Nickel hydroxides coated with different contents of cobalt hydroxide were prepared through ＂gradient eutectic technology＂ and by complex precipitation method in the atmosphere of inert gas.The phase structure,microstructure of surface and charge-discharge properties were analyzed using X-ray diffraction,scanning electronic spectroscopy and galvanostatic charge-discharge cycling technology. The results showed that the spherical nickel hydroxides enchased with cobalt hydroxide layer had good discharge capacity and huge current charge-discharge performances.The amounts of coating cobalt were determined by the charge-discharge ratios.At 0.8C charge/0.4C discharge rate,the optimum coating amount of cobalt was 0.8%.The electrode showed best performances when the contents of cobalt were between 2%～3.6% at 1C charge-discharge,2C charge/1C discharge and 3C charge-discharge rates.The result indicated that coating stable valence of cobalt hydroxide on the surface of nickel hydroxide particles was an effective method improving huge current charge-discharge characteristics of electrode.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2007年第6期784-789,共6页
Chinese Journal of Rare Metals
关键词
球型Ni(OH)2
氢氧化钴
包覆
大电流
放电容量
spherical nickel hydroxide
cobalt hydroxide
coating
huge current
discharge capacity
