To provide a nickel material which is hardly separated from a steel plate due to high jointing strength and suitable for manufacturing an electrode superior in electrical conductivity with high capacity by diffusively jointing a porous nickel plate to the steel plate via an iron-nickel alloy layer.
In a porous nickel base material 1, a porous nickel plate 2 and a steel plate 3 are jointed via a sintered body layer 4 by an iron-nickel alloy and an iron-nickel alloy layer 5. The porous nickel plate 2 is composed of a skeleton 21 of a nickel sintered body, and 14a composed of a partial flat side surface of the skeleton 21 becomes a contact plane. Since the porous nickel base material 1 is composed mainly of the porous nickel plate 2 and the steel plate 3 and is diffusively jointed via an easily solidly soluble iron-nickel alloy layer, jointing strength is enhanced. Since the porous nickel plate 2 is used, a large capacity battery can be manufactured by abundantly filling an active material, and electrical conductivity is satisfactory, since the steel plate 3 is sandwiched, so that a large electric current can be made to flow. Nickel quantity of the iron-nickel alloy layer is desirably 20 to 8%.
MAYUZUMI YOSHIYUKI
WADA MASAHIRO
WAKITA SABURO
