Patent ID: 7160643

Claim:
A battery pack comprising: a plurality of linearly aligned batteries; and a connector, disposed between two of the batteries to interlock and electrically connect the batteries, the connector being welded to the batteries to electrically connect the batteries; and a holder cap covering the interface between the two batteries that are interlocked linearly by the connector, wherein the connector includes an inner peripheral portion to be welded to one of the two batteries, an outer peripheral portion, provided outside the inner peripheral portion, to be welded to the other battery, and a step portion between the inner peripheral portion and the outer peripheral portion, the step portion placing the inner peripheral portion in a concave portion of the connector; wherein the inner peripheral portion of the connector is disposed on an interior side of a caulking strip that is provided on a battery end face of the one battery, and the inner peripheral portion is welded to the battery end face without coming in contact with the caulking strip, and wherein the outer peripheral portion of the connector is welded to an outer peripheral portion of a battery end face of the other battery such that the opposing battery end faces of the one battery and the other battery are welded with the connector, respectively, and wherein the holder cap includes a cylinder portion and a holder portion which is formed integrally with the cylinder portion, the holder portion protrudes inwardly such that the holder portion is inserted into a gap formed between the battery end face of the other battery and the outer peripheral portion of the connector in which the welded portion of the outer peripheral portion of the connector and the outer peripheral portion of a battery end face of the other battery is positioned.