La和Zn复合掺杂α-Ni(OH)_2电极材料的电化学性能

采用尿素均相沉淀法制备出稀土La和Zn复合掺杂α-Ni(OH)2样品材料,同时采用XRD、EDS、IR和TG-DSC热分析技术对样品的微结构和组成进行了测试,并研究了样品作为MH-Ni电池正极活性材料的电化学性能。结果表明,稀土La和Zn复合掺杂α-Ni(OH)2材料具有较大的晶格间距,其含有更多的结构H2O分子,电极反应的电荷转移电阻较低;样品材料电极在以0.1C充放,终止电压1.0V的制度下,其放电比容量高达372.85mAh.g-1,同时放电中值电压较高并稳定于1.30V,1C下其放电比容量高达344.07mAh.g-1,充放电循环30次容量保持率为93.04%,显示出良好的较大倍率放电性能和循环可逆及结构稳定性能。

Electrochemical performance of α-nickel hydroxide codoped with La and Zn

The rare metal La and Zn codoped α-nickel hydroxide was prepared by the urea precipitation method.The microstructure and composition of the sample were characterized by XRD, EDS, IR and TG-DSC.The electrochemical properties were also investigated when the sample codoped with La and Zn was made as the nickel electrode active material, and the MH-Ni battery was assembled.The results showed that the sample had a relatively larger interlayer distance and contained many structurally bonded water molecules, and the electrochemical reaction impedance was reduced.At 0.1 C charge-discharge rate, the discharge specific capacity reached 372.85 mAh·g^-1 when the end potential was 1.0 V, simultaneously its discharge mediate potential was higher and maintained at 1.30 V.In addition, the discharge specific capacity of the sample could reach 344.07 mAh·g^-1 at 1 C rate, and the capacity still remained 93.04% of the sample after 30 cycles.It demonstrated better high-rate discharge performance,and increased cycling and structural stability.