Toyota Jidosha Kabushiki Kaisha

Shingo Yamane

Keiichiro Kobayashi

A sealed battery disclosed herein is provided with an electrode body, a battery case, and an insulating holder. Round sections, having a curved surface, are formed between an inner surface and a bottom surface of the battery case. Deformation portions protruding towards the center, in a width direction, are formed on the inner surface of a lower end section of the insulating holder. A lower end section of a positive electrode connection portion and a lower end section of a negative electrode connection portion are press-deformed towards the center, in the width direction, by the deformation portions of the insulating holder. It becomes accordingly possible to suitably prevent short-circuits between the electrode body and the battery case, even when clearances within the battery case are made small and a width dimension of the electrode body is made large. Energy density can be suitably increased as a result.

Sealed battery

A secondary battery includes a flat wound electrode body; a battery case that accommodates the wound electrode body; and an insulating film. The wound electrode body has a first radius section opposing a top surface of the battery case, a second radius section opposing a bottom surface of the battery case, and a flat portion flanked by the first radius section and the second radius section. The insulating film is disposed between a flat surface of the flat portion of the wound electrode body and the battery case, and between a curved surface of the second radius section of the wound electrode body and the battery case. The insulating film has one groove at a portion opposing the curved surface of the second radius section and positioned between two planes resulting from extending two flat surfaces of the wound electrode body.

Secondary battery and battery pack

A power storage device includes an electrode assembly including a first electrode and a second electrode, a first collector terminal connected to the first electrode, a second collector terminal connected to the second electrode, an accommodation case which accommodates the electrode assembly, and an insulating film arranged between the accommodation case and the electrode assembly. The first collector terminal is higher in electrical conduction resistance than the second collector terminal. The insulating film is provided with a first cut at a position adjacent to the first collector terminal and a second cut at a position adjacent to the second collector terminal. The first cut is smaller in area than the second cut.

Growing community of inventors

Chiryu, Japan

Shingo Yamane