Patent ID: 7622219

Claim:
A battery pack comprising: a battery; a circuit substrate having a charge/discharge safety circuit and arranged on one end face of the battery; and an end case in which an external connection terminal is set, wherein the circuit substrate is arranged inside the end case, the end case includes attachment holes at both ends thereof extending therethrough and each attachment hole includes a step near the bottom end thereof, and the end case is secured to the battery by screws, each with a screw head, the screw head extending through a respective attachment hole and engaging with the step in the attachment hole in the end case at both ends and tips of the screws being engaged into the end face at both ends of the battery; and the battery case serves as an electrode terminal of one polarity and an electrode terminal of the other polarity is provided on the end face in the battery; a first connection bracket having an upright portion is secured to the end face of the battery case; a connection plate that makes surface contact with the upright portion of the first connection bracket and that is partly connected to the circuit substrate is arranged on the inner side of one side wall of the end case; and the upright portion and the connection plate are welded together through an aperture formed in one side wall of the end case opposite the upright portion.