Abstract: A battery pack includes a plurality of cells (2) stacked on top of one another in tiers; a heat collecting plate (4, 7) made of a wave-like metal sheet and interposed between tiers of the cells so as to make contact with outer peripheral surfaces of upper and lower tiers of the cells alternately; a heat pipe (10) having its heating portion (10a) fitted into a fitting groove (8, 9) formed in the heat collecting plate; a pack case (1) for accommodating the cells, the heat collecting plate, and the heat pipe; and a heat dissipating member (3) attached to the pack case so as to close an opening of the pack case and having on its inner-surface side a concavely-formed receiving groove (11) into which a heat dissipating portion (10b) of the heat pipe is fitted.

Abstract: A battery pack suppresses temperature rise of secondary battery during charging and discharging. The battery pack includes a plurality of batteries stacked up, a case enclosing the plurality of batteries, a heat collector disposed near the battery positioned in the center of the plurality of batteries, a heat radiator placed at one side of the case, and a first heat transfer unit placed for connecting the heat collector and heat radiator. Further, the battery pack includes a heat transfer plate placed at the other side of the case, and a second heat transfer unit placed between the heat collector and heat transfer plate.

Abstract: A battery pack includes a plurality of cells (2) stacked on top of one another in tiers; a heat collecting plate (4, 7) made of a wave-like metal sheet and interposed between tiers of the cells so as to make contact with outer peripheral surfaces of upper and lower tiers of the cells alternately; a heat pipe (10) having its heating portion (10a) fitted into a fitting groove (8, 9) formed in the heat collecting plate; a pack case (1) for accommodating the cells, the heat collecting plate, and the heat pipe; and a heat dissipating member (3) attached to the pack case so as to close an opening of the pack case and having on its inner-surface side a concavely-formed receiving groove (11) into which a heat dissipating portion (10b) of the heat pipe is fitted.

Abstract: A control circuit measures the battery voltage, intermediate voltage and discharge current of a rechargeable battery comprising a plurality of cells connected in series, at prescribed time intervals, and detects values for these parameters based on running averages for a prescribed number of measurement operations, while also detecting the battery temperature. If the battery temperature becomes equal to or greater than a prescribed temperature, or if the discharge current is an excessive current equal to or greater than a prescribed value, or if the battery voltage is equal to or less than a prescribed value, or if it is judged, from detection of the intermediate voltage that the balance between cell capacities has declined, then the control circuit halts discharge from the rechargeable battery by switching an FET to OFF.