To suppress rising of the temperature of an accumulator that exceeds the operating temperature.

The accumulator comprises a power accumulating part (21) and a terminal electrode (22) for outputting the power of the power accumulating part to the outside. At least a part of the terminal electrode is formed of low melting point metal (22a) which fuses at a temperature higher than the operating temperature of the accumulator but lower than the set temperature that causes abnormal power accumulation accompanying gas occurrence. As the metal of low melting point fuses, the power conducting volume of the terminal electrode reduces to increase the electrical resistance, thereby suppressing temperature rising of the accumulator.