Abstract: A hydrogen storage alloy electrode containing, as a principal active material, a powder of hydrogen storage alloy having a CaCu5 crystal structure and represented by the formula MmNixCoyMnzMw where M is at least one element selected from aluminum (Al) and copper (Cu), x is between 3.0 and 5.2, y is between 0 and 1.2, z is between 0.1 and 0.9, w is between 0.1 and 0.9, and the sum of x, y, z and w is between 4.4 and 5.4. The hydrogen storage alloy powder particles have a surface region and a bulk region enclosed within the surface region and have a higher nickel content in the surface region than in the bulk region. The hydrogen storage alloy electrode further contains an oxide and/or hydroxide of at least one rare-earth element selected from ytterbium (Yb), samarium (Sm), erbium (Er) and gadolinium (Gd).

Abstract: In a pasted hydrogen-absorbing alloy electrode of this invention, an active material layer made from a mixture of a hydrogen-absorbing alloy powder, a composite particle powder including carbon particles and a rare earth compound for partially coating surfaces of the carbon particles, and a binder is formed on a current collector. When this pasted hydrogen-absorbing alloy electrode is used in an alkaline storage battery, the alkaline storage battery can attain small increase of the internal pressure during charge, large discharge capacity in high rate discharge and good charge-discharge cycle performance.

Abstract: A hydrogen storage alloy electrode for a battery is made of a hydrogen storage alloy powder which includes agglomerates of hydrogen storage alloy particles joined together through a metallic layer. A method of making the electrode includes forming agglomerates of hydrogen storage alloy particles joined together by a metallic layer which covers surface portions of the particles, and then forming the electrode using a resulting powder including the agglomerates.

Abstract: A hydrogen-absorbing alloy electrode for an alkaline secondary battery. The electrode is prepared by adding a transition metal salt to a paste comprising a hydrogen-absorbing alloy powder and binder. The electrode improves charge-discharge cycle performance and high rate discharge capacity at low temperature of an alkaline secondary battery.

Abstract: A hydrogen-absorbing alloy electrode for an alkaline secondary battery. The electrode is made from a hydrogen-absorbing alloy containing nickel which has been treated with an acidic solution containing a chelating agent for nickel. The hydrogen-absorbing alloy electrode has good activity and a nickel-hydrogen battery having the hydrogen-absorbing alloy electrode as a negative electrode has a large high rate discharge capacity soon after being assembled, and inhibits an increase of internal pressure during discharge.