Abstract: A first voltage detection device (30) detects a voltage of a lead portion (150) folded back between different battery cells (100). The first voltage detection device (30) includes a first voltage detection portion (410), a first voltage detection line (420) electrically connected to the first voltage detection portion (410), and a first holding body (300) holding the first voltage detection portion (410) and the first voltage detection line (420).

Abstract: A battery module includes a plurality of battery cells and a function material. The function material is located between adjacent battery cells. The function material includes an elastic particle and a binder. The elastic particle is dispersed in the binder.

Abstract: Provided is a battery module configured so that connection among tabs and a bus bar stacked on each other is properly made. The battery module includes: multiple battery cells 10 each of which has tabs 101, 102; bus bars 152, 153 electrically connecting the battery cells to each other; and an electrical insulating bus bar holder 150 holding the bus bars 152, 153 such that the bus bars 152, 153 are arranged apart from each other in parallel. The bus bar holder 150 has, in regions adjacent to the bus bars 152, 153, slit openings 156b to 156e through which the tabs 101, 102 are drawn. The bus bars 152, 153 include plate-shaped tab connection portions standing on an outer peripheral surface of the bus bar holder 150 and joined to the tabs 101, 102.

Abstract: A first fuse device includes a first conductor, at least a portion of the conductor being functioning as a fuse, and a first wiring electrically connected to the first conductor. At least a portion of the first wiring passes through a first space of the first conductor, the first space being defining the fuse.

Abstract: A first voltage detection device includes a plurality of first voltage detection portions connected to a plurality of lead portions of a plurality of battery cells, a first holding body holding the plurality of first voltage detection portions, and an insulator provided at the first holding body, at least a portion of the insulator being located between the different lead portions.