Alkaline storage battery

An alkaline storage battery comprising:

• an electrode group fabricated by rolling a positive electrode using nickel hydroxide as a main positive electrode active material and a hydrogen storage alloy negative electrode using a hydrogen storage alloy as a negative electrode active material into a spiral form with a separator keeping the two electrodes apart interposed therebetween;
• an alkaline electrolyte;
• and
• an outer can containing the electrode group and the alkaline electrolyte inside thereof;
• the hydrogen storage alloy negative electrode being formed in a strip form including a long axis and a short axis, in which a ratio (A/B) of a length A (cm) of the long axis to a length B (cm) of the short axis is 20 or more and 30 or less (20≦A/B≦30),
• a ratio (X/Y) of an electrolyte mass X (g) retained in the hydrogen storage alloy negative electrode to an electrolyte mass Y (g) retained in the separator being 0.8 or more and 1.1 or less (0.8≦X/Y≦1.1);
• the hydrogen storage alloy negative electrode including a hydrogen storage alloy used as a negative electrode active material, an adhesive paste made of a thermoplastic elastomer, and a carbon conductor;
• a ratio Z (m2/cm3) of a surface area of the negative electrode (m2) to a unit volume (1 cm3) of a negative electrode active material is 31 m2/cm3 or more and 117 m2/cm3 or less (31 m2/cm3≦Z≦117 m2/cm3);
• the hydrogen storage alloy includes a component A composed of elements including at least a rare earth element and magnesium, and a component B composed of element(s) including at least nickel but excluding manganese and cobalt;
• and
• the hydrogen storage alloy has A5B19, A2B7 and AB5 type structures, and has a primary alloy phase of an A5B19 type structure;
• wherein surface area Z (m2/cm3) of a negative electrode per unit volume of an active material as calculated based on the following equation (1) using specific surface areas S1, S2, and S3 (m2/g) determined by BET method in each component (hydrogen storage alloy, carbon conductor, thermoplastic elastomer) of an active material, additive amounts G1, G2, and G3 (g) of each component, volume V (cm3) of active material after rolling:
• Z(m2/cm3)=(S1×G1+S2×G2+S3×G3)/V (1).