添加Mg2+和PO43-非晶态氢氧化镍电极活性材料的性能  

Performance of Mg^(2+) and PO_4^(3-)Codoped Amorphous Ni(OH)_2 Electrode Active Materials

作　　者：刘长久 黄良花 孙丹 吴华斌 

机构地区：[1]Guilin Univ Technol, Dept Mat & Chem Engn, Guilin 541004, Peoples R China

出　　处：《稀有金属材料与工程》2010年第9期1609-1613,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助项目(20563001);广西科学研究与技术开发项目(桂科能0842003-12);广西研究生教育创新计划资助项目(2008105960817M21)

摘　　要：采用快速冷冻沉淀法制备添加PO43-和Mg2+阴阳离子的非晶态氢氧化镍电极活性粉体材料,对其微结构和电化学性能进行研究。结果表明:添加5%PO43-(质量分数,下同)和2%Mg2+的非晶态样品粉体形貌为无规则,微结构无序性强,含有较多的结晶水,达31%。其作为MH-Ni电池正极活性材料,放电容量为347mAh·g-1,中值电压达1.29V,放电倍率对样品电极的放电比容量影响不大;充放电循环50次,容量衰减为3.5%,具有较好的稳定性;质子扩散系数达9.22×10-10cm2·s-1,并具有较小电化学阻抗。与β-Ni(OH)2材料相比,其电化学性能明显提高。Amorphous electrode active material, nickel hydroxide powder codoped with PO43- and Mg2+ was synthesized by the method of quick cryoprecipatation. Its microstructure and electrochemical performance were studied. Results show that the shape of the amorphous sample codoped with 5wt% PO43- and 2wt% Mg2+ is abnormal, the randomness is strong and it contains a large amount of crystal water up to 31%. As the positive active material of MH-Ni battery, the discharge specific capacity of the codoped sample is 347 mAh.g(-1), and the discharge mean voltage reaches to 1.29 V. The discharge rate has a little effect on the discharge specific capacity of the electrode sample. The stability of electrode material is good after the 50 times circulation of charging and discharging and the capacity decrement is only 3.5%; the proton diffusion coefficient is 9.22x10(-10) cm(2).s(-1) and the electrochemical impedance in the electrochemical reaction is small. The electrochemical performances of the sample are much better than those of beta-Ni(OH)(2) applied in MH-Ni production.

关 键 词：非晶态氢氧化镍 电极活性材料 电化学性能 Performance Materials 质子扩散系数 正极活性材料 微结构 放电比容量 充放电循环 沉淀法制备 MH-NI电池 质量分数 阴阳离子 样品 容量衰减 快速冷冻 粉体形貌 粉体材料 放电容量 

分 类 号：TM911.14[电气工程—电力电子与电力传动]