摘要 |
In order to provide a highly-reliable battery back in which a laminate film of a unit battery does not break through a laminate film of an adjacent unit battery even under vibration, a battery pack of the present invention is characterized by including a plurality of unit batteries 100 connected in series, the unit batteries 100 including: a positive-electrode pulled-out tab 120 and a negative-electrode pulled-out tab 130; and a laminate casing member that is provided with a first end portion 111, from which the positive-electrode pulled-out tab 120 and the negative-electrode pulled-out tab 130 are pulled out, a second end portion 112, which faces the first end portion 111, a first fusion-bonding portion 117, which has a first fusion-welding length in a direction in which a tab is pulled out at a first end portion 111's side, a second fusion-bonding portion 118, which has a second fusion-welding length that is shorter than the first fusion-welding length in a direction in which a tab is pulled out at a second end portion 112's side, and chamfered portions 119, which are positioned at both corner portions of the second end portion 112. |