ALKALINE BATTERY

PROBLEM TO BE SOLVED: To prevent sudden generation of gas in large quantities due to short circuiting of battery. SOLUTION: An alkaline battery comprizes a hollow tubular positive electrode active material 6 filled within a bottomed tubular positive electrode can 4 along an inner circumferential surface of the positive electrode can 4, a separator 8 mounted on an inside surface of the positive electrode active material 6, and a negative electrode active material 10 filled inside the separator 8. A lower end opening part 8a of the separator 8 is closed with an insulation material 30 and therefore the negative electrode active material 10 and an inner bottom surface 4a of the positive electrode can 4 are isolated from each other. This insulation material, comprizing a heat contraction material, contracts along radial directions of the positive electrode can 4 due to heat generated by short circuiting when the battery is externally short-circuited and releases the lower end opening part 8a of the separator 8. The positive electrode active material 6 and the negative electrode active material 10 are thereby short- circuited via the positive electrode can 4, and a short-circuited state continues within the battery even if external terminals are released from the short circuit and sudden generation of gas in large quantities can be prevented.