Hitachi Automotive Systems, Ltd.

Hitachi Vehicle Energy, Ltd.

Vehicle Energy Japan Inc.

Takuro Tsunaki

Kazuaki Urano

Masaaki Iwasa

Keisuke Sawada

Sho Saimaru

Yutaka Sato

Sho Matsumoto

Mitsuru Koseki

Takashi Sasaki

Kinya Aota

Naoki Kimura

Kouichi Kajiwara

Fujio Hirano

Takenori Ishizu

Kiyoyuki Sekine

Ryuji Kono

Hideyuki Shibanuma

Hidemasa Kawai

Ryuji Kohno

Shou Saimaru

Provided is a rectangular secondary battery with improved rigidity against vibrations and impacts. A rectangular secondary battery of the present invention includes: a flat-shaped electrode group; a current-collecting plate electrically connected to the electrode group; a battery case accommodating the current-collecting plate and the electrode group; a battery cover that closes an opening of the battery case; an electrode terminal penetrating through the battery cover, the electrode terminal being connected to the current-collecting plate via a connecting member; and a gasket that is inserted between the electrode terminal and the battery cover for insulating and sealing. An insulator is disposed between the current-collecting plate and the battery cover, the battery cover includes a battery cover side fixing part that fixes the insulator, and the insulator includes a current-collecting plate side fixing part that fixes the current-collecting plate.

Rectangular secondary battery

Provided is a secondary battery which is capable of more reliably cutting off current by increasing a deformation amount of a member, which is deformed by a rise of an internal pressure of a battery container and cuts off current. The secondary battery is provided with a current cut-off mechanism in a current path between an external terminal and an electrode inside a battery container. The current cut-off mechanism is accommodated in the battery container, and is provided with a diaphragm connected to the external terminal and a current collector connected to the electrode. The diaphragm is disposed on an outer side of the battery container than the current collector and has a convex shape toward an inside of the battery container. The current collector includes a concave portion on a surface facing the outer side of the battery container, and the diaphragm is bonded to the concave portion.

Secondary battery

Provided is a secondary battery which can more securely suppress vibrations applied to a current interrupting mechanism. A secondary battery including: a current interrupting mechanism that interrupts a current path between an external terminal and an electrode in a battery container. The current interrupting mechanism includes a collector plate that is connected to the electrode, a diaphragm that is connected to a base portion of the collector plate and disconnected from the base portion by being deformed when a pressure in the battery container is increased, and an insulating member that fixes the diaphragm and the base portion of the collector plate on the inside of the battery container. The insulating member includes a plurality of projections that protrude in a thickness direction of the base portion, and the base portion includes a plurality of notches through which the projection passes in the thickness direction. The projection includes an engaging member that is engaged with an end surface of the base portion on a side opposite to the insulating member and a side surface of the base portion along the thickness direction.

A rectangular secondary battery () includes a current interrupting portion () disposed in a current path between a collector plate () connected to a rolled electrode group () and an external terminal () disposed outside a battery container () and configured to interrupt the current path when an internal pressure of the battery container () is increased. The current interrupting portion () has a diaphragm () electrically connected to the external terminal () and deformed when the internal pressure of the battery container () is increased, a connection plate () connected to the diaphragm and disconnected from the diaphragm by the deformation of the diaphragm, and a connecting portion () connecting the connection plate and collector plate. A rigidity of the connecting portion () is lower than that of the collector plate ().

A square secondary battery includes a generating element having an electrode; a battery can holding the generating element; a battery lid that seals an opening of the battery can; an external terminal arranged on the battery lid; and a current collector connecting the electrode of the generating element to the external terminal. The external terminal has a bus bar joint to which a bus bar is connected and a current collector joint to which the current collector is connected, the bus bar joint and the current collector joint being integrally juxtaposed on the battery lid. The current collector joint has a cylindrical insertion part to be inserted into a through hole in the battery lid and also has a sealing part arranged at an outer periphery of the insertion part, the sealing part pressing down a sealing member.

Square secondary battery

A rectangular secondary battery () includes a current interrupting portion () disposed in a current path between a collector plate () connected to a rolled electrode group () and an external terminal () and configured to interrupt the current path when an internal pressure of a battery container () is increased. The current interrupting portion () has a diaphragm () whose top portion () is electrically connected to the collector plate () and whose edge portion () is electrically connected to the external terminal (). The diaphragm () is formed into a convex shape protruding inside the battery container () and into a planar shape elongated in a longitudinal direction of the battery container ().

A square secondary battery includes a can housing a power generation element, a lid sealing an opening of the can, an external terminal arranged on the lid, a current collector connected to each of the electrodes of the power generation element, and a connection terminal connecting the current collector and the external terminal by passing through the lid. The external terminal has a flat plate shape arranged along the lid and is made of a clad material in which two flat plate portions made of mutually dissimilar metals are clad-joined on wide-width surfaces and the connection terminal is joined by welding with, of the two flat plate portions of the external terminal, the flat plate portion arranged on a side of the lid.

A secondary battery typified by a lithium-ion secondary battery includes a battery outer container in which a gas release valve and positive and negative electrode external terminals are provided, an electrode group in which positive and negative plates are stacked with a separator interposed therebetween and current collection portions are provided at both ends, and positive and negative electrode current collectors forming a current path from the current collection portions of the electrode group to the positive and negative electrode external terminals, and the cross-sectional area of a gas exhaust flow channel through which gas generated inside the electrode group is discharged from the gas release valve is set so as to increase in a downstream direction.

A rectangular secondary battery includes a current breaking mechanism with improved rigidity against vibration and impact. The current breaking mechanism is interposed in the middle of a current path electrically connected between an external terminal and a wound electrode group to break the current path by the rise of battery internal pressure. The current breaking mechanism includes a connection electrode arranged inside a battery lid and electrically connected to the external terminal, and a conductive plate bonded to the connection electrode and deformed by the rise of the battery internal pressure. The connection electrode includes a tabular member having a through hole in communication with the outside of the battery opening on a planar portion. The conductive plate includes a dome-shaped diaphragm portion gradually reducing its diameter as shifting in an axial direction and a flange portion extending radially outward from an outer peripheral portion of the diaphragm portion.

Secondary battery with current breaking mechanism

An electrical storage element includes a power generation element that includes an electrode, a can in which the power generation element is stored, a lid that seals an opening of the can, an external terminal that is disposed on the lid, and a current collector that connects the electrode of the power generation element, and the external terminal. The external terminal includes a bus bar welding portion having a bus bar welding surface to which a bus bar is welded, and a current collector connection portion having a caulking-jig abutting surface, the current collector connection portion includes an insertion portion which is inserted into a through-hole of the lid and has a tip end which is fixed to the current collector by caulking, the bus bar welding portion and the current collector connection portion are integrally provided in parallel on the lid, and the jig abutting surface is extended from the bus bar welding surface in the same plane as the bus bar welding surface.

Electrical storage element

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

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

Hitachinaka, Japan

Takuro Tsunaki