Toyota Jidosha Kabushiki Kaisha

Toru Nakai

Hideyo Ebisuzaki

Hiroshi Hamaguchi

Masaru Ishii

Mizuho Matsumoto

Hiroshi Ueshima

Yukimasa Nishide

Nobuo Yamamoto

Provided is a nonaqueous electrolyte secondary battery that allows a current cutoff mechanism to operate appropriately while maintaining high battery performance. The nonaqueous electrolyte secondary battery according to the present invention includes: a battery assembly provided with a positive electrode having a positive electrode active material layer retained on a positive electrode current collector, a negative electrode and a separator; a battery case housing the electrode assembly together with a nonaqueous electrolyte; and a current cutoff mechanism. The positive electrode active material layer includes a positive electrode active material and a conductive material. A compound containing a saturated cyclic hydrocarbon group is retained in at least a portion of the conductive material. The content of the compound containing a saturated cyclic hydrocarbon group is 0.5% by mass or more based on a value of 100% by mass for the total solid content of the positive electrode active material layer.

Nonaqueous electrolyte secondary battery

Provided is a non-aqueous electrolyte secondary battery that can achieve both battery characteristics during normal usage and resistance to overcharging at high levels. In this non-aqueous electrolyte secondary battery, an electrode body, which includes a positive electrode and a negative electrode, and a non-aqueous electrolyte are housed in a battery case. The battery case is provided with a current interrupt mechanism that activates when the pressure inside the case increases. The non-aqueous electrolyte contains cyclohexylbenzene and 4,4'-difluorobiphenyl as gas generating agents that decompose and generate gas when the battery reaches an overcharged state. In addition, when the overall quantity of the non-aqueous electrolyte is taken to be 100 mass %, a ratio of the content (mass %) of the 4,4&#x2032;-difluorobiphenyl (W2) relative to the content (mass %) of the cyclohexylbenzene (W1) (W2/W1) is 0.025 to 0.25.

Non-aqueous electrolyte secondary battery

A cell has: a pole terminal placed on outside of a cell case; a deformed terminal fixing the pole terminal to the case by a base surface portion and a protruding portion; an inversion plate attached to the base surface portion and interrupting conduction between the internal terminal and the deformed terminal by inversion deforming away from the internal terminal at least at a portion when the internal pressure of the case increases beyond working pressure; and a shaft member having at least a part of the top portion placed in the protruding portion, and reestablishing conduction between the internal terminal and the deformed terminal after the inversion plate inverted by the top portion being pressed from the outside and thereby being moved inside the protruding section to press the inversion plate inward. A sealed space is provided between the deformed terminal and the inversion plate.

Sealed-type cell

An electric storage apparatus has an electric-generating element performing charge and discharge and a case accommodating the electric-generating element and an electrolytic solution. The case has an injection portion, a cap, a worked portion, and a valve. The injection portion is used for injecting the electrolytic solution into the case. The cap closes the injection portion. The worked portion is formed along the outer shapes of the injection portion and the cap by working the wall face of the case. The valve is used for discharging gas produced within the case to the outside of the case and is provided between the injection portion and the worked portion.

Electric storage apparatus

A battery includes a casing made of metal; and a safety valve made of a thin plate. The casing includes a vent hole that provides communication between the inside of the battery and the outside of the battery. A seal member made of synthetic resin is provided between the peripheral edge portion around the vent hole and the peripheral edge portion of the safety valve. The seal member connects the peripheral edge portion around the vent hole to the peripheral edge portion of the safety valve such that the peripheral edge portion around the vent hole does not contact the peripheral edge portion of the safety valve.

Growing community of inventors

Kiyosu, Japan

Toru Nakai