Toyota Jidosha Kabushiki Kaisha

Yukinobu Miyamura

Hiroya Umeyama

Hiroaki Imanishi

Tatsuya Hashimoto

Tomohiro Matsuura

Koichi Toriyama

Koji Torita

There is provided a power storage device including: a power storage assembly; and a plurality of joined portions, each of the plurality of electrode plates including an electrode plate main body and a tab, the plurality of electrode plates being disposed such that the tabs are arranged in the stacking direction, the plurality of joined portions including a first joined portion configured to join the plurality of tabs to form a first bundle portion, and a second joined portion configured to join the plurality of tabs arranged in the stacking direction to form a second bundle portion, a part of the tabs in the first bundle portion and a part of the tabs in the second bundle portion being joined to the first joined portion and the second joined portion.

Power storage device

A secondary battery includes a reverse plate formed using a conductive material and provided in a case, and a fixing member formed using an elastically deformable material and joined to the reverse plate. When an internal pressure in the case is increased, the reverse plate deforms in response to the internal pressure, to thereby electrically connect a positive electrode terminal and a negative electrode terminal. With the increase in the internal pressure, the fixing member elastically deforms from a state where it is inserted into the through hole, exits the through hole and is fixed between the reverse plate and the case. The reverse plate in the deformed state is supported by the fixed fixing member.

Secondary battery

A secondary battery includes a scaling body (), a rivet member (), a gasket () that contacts the rivet member () and is fixed between the sealing body () and the rivet member (), a holder member (), a reversing plate () that deforms when an internal pressure of the exterior body () rises, and a heat accumulation portion () that contacts the rivet member () and has a higher thermal conductivity than the rivet member (). An outer peripheral edge () of the reversing plate () is connected by welding to the peripheral edge portion () of the rivet member (), and the heat accumulation portion () is sandwiched between the opposing portion () of the rivet member () and the extending portion () of the holder member ().

Secondary battery and manufacturing method of secondary battery

A secondary battery includes: a battery element; a case housing the battery element; a positive-electrode external terminal and a negative-electrode external terminal provided outside the case and electrically connected to the battery element; and a short-circuiting mechanism configured to establish a short-circuit between the positive and negative external terminals through the case. The short-circuiting mechanism includes a conducting portion conductively connected to one of the positive and negative external terminals so as to face the case, an inversion plate provided at a portion of the case facing the conducting portion and configured to deform to approach the conducting portion when an internal pressure of the case rises, and a brazing material provided on one of the conducting portion and the inversion plate at a position between the conducting portion and the inversion plate.

A secondary battery includes a current cut-off device that cuts off a current flow between a battery element and an external terminal of a positive electrode, and a bypass member electrically connected to an external terminal of a negative electrode. The current cut-off device includes a current collecting member electrically connected to the battery element inside an outer casing, and an inversion plate electrically connected to the current collecting member. The inversion plate comes apart from the current collecting member when the inner pressure of the outer casing becomes increased so as to cut off conduction between the battery element and the external terminal of the positive electrode, and becomes further deformed to electrically connect the bypass member and the external terminal of the positive electrode.

Secondary battery and battery pack

An inversion plate short-circuits the positive electrode external terminal and the negative electrode external terminal to each other by changing its position. A temperature sensitive member is disposed adjacent to the inversion plate on the side opposite to a direction in which the inversion plate changes its position. The volume of temperature sensitive member increases due to a rise in temperature. The temperature sensitive member contains aluminum phosphite and calcium carbonate.

Growing community of inventors

Osaka, Japan

Yukinobu Miyamura