Hitachi Automotive Systems, Ltd.

Hitachi Vehicle Energy, Ltd.

Ryuji Kohno

Takuro Tsunaki

Yutaka Sato

Takashi Sasaki

Kenji Kubo

Susumu Harada

Sho Saimaru

Mitsuru Koseki

Masayuki Nakamura

A secondary battery includes a battery casing accommodating an electricity-generating element group, and a battery cover having through-holes and sealing an opening in the battery casing. A first face at one end of each of positive and negative electrode connecting plates, which are each formed from a single plate of metal, is connected to a non-coated section of the electricity-generating element group. A second face at the other end of each of the positive and negative electrode connecting plates is a face onto which a busbar is welded, and the second face is exposed outward from one of the through-holes. Insulating base materials are interposed between THE positive and negative electrode connecting plates and an outer circumference of each through-hole, the insulating base materials and the battery cover are connected by brazing, and the insulating base materials and the positive and negative electrode connecting plates are connected by brazing.

Secondary battery and secondary battery module

An electricity storage module includes: an electric storage unit block that is constituted by arraying a plurality of prismatic electric storage units through a holding member; and a cooling channel that is formed between the electric storage unit and the holding member, through which a cooling medium for cooling the electric storage unit flows. A part of a cooling medium inlet opening of the cooling channel is covered so that a flow speed of a cooling medium after flowing into the cooling channel is higher than a flow speed of a cooling medium before flowing into the cooling channel.

Electricity storage module

A secondary battery has: an electrode group which includes sheet-form positive and negative electrode plates each including a metallic foil having an active material applied onto both sides of the metallic foil, and a separator disposed between the positive and negative electrode plates, wherein the positive and negative electrode plates and the separator are spirally wound together around a winding core into a flattened shape, wherein the electrode group has, at the both ends thereof as viewed in the winding core direction, respectively formed metallic foil exposed portions of the positive and negative electrode plates onto which the active material is not applied; a battery container which contains the electrode group therein, wherein the battery container has a battery casing and a battery cap; and positive and negative external terminals electrically connected to the metallic foil exposed portions of the positive and negative electrode plates, respectively. Winding end portions in the metallic foil exposed portions of the positive and negative electrode plates are arranged opposite to the inner surface of the battery container through respective conducting members.

Secondary battery and method for producing the same

A secondary battery adapted to minimize deterioration attributable to temperature is provided. In the secondary battery, a cross-sectionally elliptic electricity-generating element group in which a positive electrode sheet including at one side in a longitudinal direction thereof a section not coated with an active material mixture, and a negative electrode sheet including at one side in a longitudinal direction thereof a section not coated with an active material mixture are wound via separators is accommodated in a battery container. When a planar region of the electricity-generating element group is seen in plan view, the number of connections between the non-coated section of the positive or negative electrode sheet and a connecting surface of a positive or negative electrode connecting sheet is two for each of positive and negative electrodes, and a distance between the two connections is greater than &#xbc; of innermost circumferential length of the electricity-generating element group, but is smaller than &#xbc; of outermost circumferential length of the electricity-generating element group.

Secondary battery

A secondary battery includes a gas release valve located at a battery container housing a power generating element, wherein: the gas release valve includes a valve disk caused to expand outward by internal pressure in the battery container; wherein a plurality of grooves are formed at the valve disk in order that a plurality of valve element pieces become fractured along the grooves when the valve disk expands due to the internal pressure; and a scatter-deterring portion is formed at the valve disk in order to prevent the fractured valve element pieces along the grooves from scattering away from the valve disk.

Growing community of inventors

Mito, Japan

Ryuji Kohno