AB5型球形合金粉的表面处理研究

由雾化（Gas－atomization）技术制备的AB5型球形合金粉，作为镍氢电池负极材料具有很多优点：粉粒呈球状便于在多孔基片内装填；耐压耐磨性好；抗碱能力强且不易解胶．但它的电化学初活性差，难于活化．有碍电池中的应用．采用适宜的氧化剂（铜盐水溶液）处理，使球粒表面形成一个富铜、富镍亚层，显著地改善了合金粉的电化学活性．经处理的MlNi3.8CO0.5Mn0.3Al0.4球形合金粉，仅3次充放电循环其放电量便可达到240mA·h·g-1；而未经处理的同一合金粉即便经6次充放电循环其放电量也只有103mA·h·g-1．

Study of Surface Treatment for Gas-atomized AB_5 Alloy Powder

The AB_5 alloy powders prepared by gas-atomization have many advantages: sphericalparticles convenient for packing. high press and wear resistance, enhanced corrosion and dispersion resistance. But lack of electrochemical activity is a barrier for use in Ni-MH battery. Anactivation method have been carried out in our laboratory. The gas-atomized powder was treatedby an oxidizer (a solution of copper salt) to form a Cu and Ni-rich layer on the surface of theparticles. The activity of the gas-atomized powder was greatly improved. For the treated powderMINi3.8Co0.5Mn0.3Al0.4, it was found that the discharge capacity after 3 cycles of charge-dischargereached an ideal value 240mA.h.g- 1, but only 103 mA.h.g- 1 for the non-treated powder.