Abstract: A method including the steps of assembling a battery pack core; holding the core in a mold that forms a molded resin region; closing a cavity of the mold; injecting synthetic resin into the closed cavity; and ejecting the battery pack from the cavity to configure the battery pack with the battery pack core insert-molded in the molded resin region. A projection that protrudes towards an inner surface of the mold cavity is provided on the surface of the insulating cover fixed on the battery. In the resin injection step, the projection on the insulating cover is pressed directly or indirectly by the mold in a direction to put the insulating cover tightly in contact with the surface of the battery; and synthetic resin is injected into the cavity of the mold in this pressed configuration.

Abstract: In a battery pack, a battery core pack having a connector is inserted into a resin molded portion which is formed of a plastic material. The battery core pack includes a rechargeable unit cell, a circuit board electrically connected to the unit cell, and a connector fixed to the circuit board. The connector incorporates a contact point in a connector casing which is formed of an insulation material, and the connector casing is inserted into the resin molded portion so as to partially appear to a surface of the resin molded portion. Further, the battery pack is provided with a sealing groove at a boundary between the connector casing and the resin molded portion, along a peripheral edge of an exposed portion of the connector, appearing outside the resin molded portion.

Abstract: A method comprising: assembling a battery pack core; holding the core in a mold that forms a molded resin region; closing a cavity of the mold; injecting synthetic resin into the closed cavity; and ejecting the battery pack from the cavity to configure the battery pack with the battery pack core insert-molded in the molded resin region. A projection that protrudes towards an inner surface of the mold cavity is provided on the surface of the insulating cover fixed on the battery. In the resin injection step, the projection on the insulating cover is pressed directly or indirectly by the mold in a direction putting the insulating cover tightly in contact with the surface of the battery; and synthetic resin is injected into the cavity of the mold in this pressed configuration.