摘要
采用化学共沉淀法,制备出Cl-和Zn2+阴阳离子复合掺杂α-Ni(OH)2粉体。样品材料利用XRD、EDS、SEM、IR、DSC-TG和粒度测试仪进行结构形态及物理特性表征分析。同时以其为活性物质合成镍正极材料并组装MH-Ni电池,测试其充放电、循环可逆特性和交流阻抗等电化学性能。实验结果表明,在掺杂物质摩尔比为Cl-:Zn2+=1:3时,Cl-和Zn2+复合掺杂α-Ni(OH)2为层状结构,结晶水含量较高,热分解温度低。其MH-Ni电池在以80mA/g恒流充电5h,40mA/g恒流放电至终止电压为1.0V的充放电制度下,电化学极化阻抗较小,放电比容量为354.08mAh/g,放电平台平稳、中值电压高达1.313V,且经过多次充放电循环后,其电极活性物质仍然保持α-Ni(OH)2状态,电极过程结构稳定,循环可逆性较好,具有较高的电化学活性。
The Zn^2＋ and CI cation and anion Co-doped composite powder α-Ni（OH）2 was prepared by chemical co-precipitation.The structure characteristics of the prepared sample were analyzed by XRD, EDS, SEM, IR, DSC-TG and particle size tester. Taking the sample as cathode material, assembleing it to get MH-Ni battery, the charge-discharge performance, circular reversibility characteristic and alternating-current impedance etc. were tested. Experimental results show when the doped powder mol rate is Cl^-：Zn^2＋ =1：3, the Cl^- and Zn ^2＋ Co-doped α-Ni（OH）2 has lamellar structures, a relatively higher crystal water content and lower thermal decomposition temperature. Under the condition of charging at 80 mA/g for 5 h and 40 mA/g discharging to the final voltage at 1.0 V, MH-Ni battery assembled with the cathode material has a low electrochemical impedance, the discharge voltage smoothed at 1.313 V and the discharge specific capacity with 354.08 mAh/g. Further the more, after many times of charge-discharge cycles, the cathode material keeps a phase of Ni（OH）2, still the electrode process is steady-going, the circular reversibility is relatively good.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2008年第3期499-503,共5页
Rare Metal Materials and Engineering
基金
广西科学研究与技术开发计划项目(桂科基0731001)
