ELECTROCHEMICAL ACTIVATION BEHAVIOR OF HYDROGEN STORAGE ALLOY PRODUCED BY GAS-ATOMIZATION METHOD

In order to improve the initial electrochemical activity of the hydrogen storage alloy prepared by means of gas-atomization method, the alloy powder surface was treated by an Al3+containing aqueous solution and the electrochemical properties of the alloy powder before and after treatment were measured. It was found that surface treatment was significantly effective on improving the initial electrochemical properties of the alloy powder. For the treated alloy. the initial discharge capacity reached 231mA.h.g-1, but only 185mA.h.g-1 for the non-treated alloy even at the fifth cycle of charge-discharge. AES and XPS results showed that the oxide layer formed on the surface plays a key role on the activation process of the gas-atomized alloy in alkaline solution.