钴的添加形式对氢氧化镍电极性能的影响

研究了钴元素分别以Co ,CoO ,Co +CoO三种形式作为添加剂并分别以与Ni(OH) 2 用机械混合的方式添加到电极活性物质中时对镍电极性能的影响 ,用循环伏安法和电化学交流阻抗法对实验结果进行分析 .结果表明 :对于机械混合的添加方式 ,Co ,CoO和Co +CoO三种形式的钴添加剂均可在一定程度上改善镍电极的性能 .其中 ,当钴以CoO的形式添加时镍电极的性能最好 .这是因为三种形式的添加剂均在一定程度上改善了活性物质Ni(OH) 2 的结构、增强了电极中质子的传输能力 ,从而提高了镍电极反应的可逆性 ,强化了镍电极的析氧极化 ,并提高了镍电极的充电效率 ,其中CoO的作用效果最明显 .

Effect of Different Species of Cobalt Additive on Performance of Nickel Hydroxide Electrode

Performances of nickel electrodes when adding or without adding Cobalt in different forms were studied, the results were interpreted by cyclic voltammetry(CV)and electrochemical impedance spectroscope(EIS). It was demonstrated that the additions of Co,CoO,CoO+Co by mechanically mixing with Ni(OH) 2 all can improve the performance of nickel electrode to some extent,and when Co is added in the form of CoO the best performance can be obtained. This can be mainly attributed to the fact that three kinds of Co additives all improved the structure of nickel hydroxide and the ability of H + in electrolyte transporting through the material,hence the reversibility of nickel electrode and the oxygen evolution potential are increased. These improved the charging efficiency of nickel electrode, accordingly, improved the performance of nickel electrode.