Sanyo Electric Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Shinichirou Yoshida

Eiji Okutani

Hiroyuki Inoue

Yohei Muroya

Hiroshi Maesono

Takenori Tsuchiya

Toyoki Fujihara

Toshihiro Takada

Hiroshi Takabayashi

Tomokazu Yamanaka

Tetsuya Okado

Masashi Muraoka

Takuya Yamawaki

Tomoharu Arai

Takashi Tokunaga

Atsushi Miyazaki

A highly reliable secondary battery is provided, in which a short circuit between a positive electrode plate and a negative electrode plate is prevented. The negative electrode plate includes a negative electrode core and a negative electrode active material layer formed on the negative electrode core. An electrode assembly includes a negative electrode core-stacked portion including stacked layers of the negative electrode core, and the negative electrode core-stacked portion is joined to a first surface of the negative electrode current collector to form a joined portion. The irregularity-formed portion is formed on a second surface of the negative electrode current collector that is opposite to the first surface and is located in a portion of the negative electrode current collector in which the joined portion is formed. A sheet member used as a cover member is disposed on the second surface so as to cover the irregularity-formed portion.

Secondary battery and method for producing the same

A square secondary battery includes an electrode body including a positive electrode plate and a negative electrode plate, a square outer package housing the electrode body, a metal sealing plate sealing an opening of the square outer package, and a positive electrode collector electrically connected to the positive electrode plate and the sealing plate. The positive electrode collector includes a base portion disposed to oppose the sealing plate, and a lead portion extending from an edge portion of the base portion towards the electrode body. In a short direction of the sealing plate, a boundary between the base portion and the lead portion is positioned on a first side with respect to a center of the sealing plate, and a connection between the sealing plate and the base portion of the positive electrode collector is offset to a second side with respect to the center of the sealing plate.

Square secondary battery and method of manufacturing same

A battery includes: an electrode body; an electrode current collector; a sealing body; an external terminal; an electrical conductor connected to the external terminal; a deforming plate sealing an opening of the electrical conductor, electrically connected to the electrical conductor and to the current collector, and deformed when an internal pressure reaches a predetermined pressure; and a first insulator between the deforming plate and the current collector. The current collector includes a base, and a lead connecting to the electrode body. First to fourth fasteners fasten the base and the first insulator. Between the first and second fasteners, the base is electrically connected to the deforming plate. The second fastener is closer to the lead than the first fastener. The second fastener is closer to a connection between the deforming plate and the electrode current collector than a position of the first insulator supported toward the sealing body.

Square secondary battery

A secondary battery including an electrode body that includes a positive electrode plate and a negative electrode plate, an outer body that houses the electrode body, a metal sealing plate that seals an opening of the outer body, a positive electrode collector electrically connected to the positive electrode plate and the sealing plate, a negative electrode external terminal connected to the negative electrode plate through a negative electrode collector. In the secondary battery, a first projection and a second projection are formed on a surface of the sealing plate on a battery inner side, the positive electrode collector includes a first opening and a cut-out, the first projection is disposed in the first opening, the first projection and an edge portion of the first opening is welded and connected to each other, and the second projection is disposed in the cut-out.

Secondary battery, method for manufacturing same, and battery pack employing same

A prismatic secondary battery includes a first current collector and a second current collector. The first current collector includes a first base disposed along a sealing plate. The second current collector includes a second base disposed along the sealing plate. A distance between an end portion of a wound electrode body facing the sealing plate and a surface of the first base facing the wound electrode body at an end portion of the first base on a central side in the longitudinal direction of the sealing plate is shorter than a distance between the end portion of the wound electrode body facing the sealing plate and a surface of the second base facing the wound electrode body at an end portion of the second base on the central side. An insulating buffer is disposed between the wound electrode body and the above surface of the first base.

Prismatic secondary battery

A battery includes a battery case, an electrode assembly, positive and negative electrode collectors, a sealing body, an external terminal, a conducting member, a deforming plate, and a first insulating member. The positive or negative electrode collector has a base portion facing the first insulating member, and a lead portion connected to the electrode assembly. A fixing portion fixing the base portion and the first insulating member to each other is provided in the first insulating member. The fixing portion is located nearer to the connection portion between the deforming plate and the positive or negative electrode collector than the sealing body side support position of the first insulating member. The outer peripheral edge of the electrode assembly side surface of the first insulating member is provided with a rib protruding to the electrode assembly side and extending along the outer peripheral edge of the base portion.

Secondary battery

A prismatic secondary battery includes an electrode assembly, a casing having an opening, a sealing plate sealing the opening, a terminal connected to an electrode that constitutes the electrode assembly, and a current collector connected to the electrode. The current collector has a base portion located along the sealing plate and a lead portion extending from an end portion of the base portion toward a bottom of the casing. The base portion is welded to the terminal. The lead portion is connected to a substrate exposure portion of the electrode and has a fusible portion that is fusible by an excessive current and that has a smallest cross section compared to the remaining portion. The fusible portion has a cross section equal to or smaller than 92% of a cross section of the base portion that passes through an end portion of a weld-connection portion closer to the lead portion.

An insertion portion of a negative electrode terminal is inserted into through-holes provided in an outer insulating member, a sealing plate, an inner insulating member, and a terminal connection portion of a negative electrode collector, and the insertion portion is crimped. A countersunk hole is provided around the through-hole of the terminal connection portion. The insertion portion of the negative electrode terminal is radially expanded in the countersunk hole. A distal end of a thin portion provided at a distal end of the crimped part of the insertion portion and the edge of the countersunk hole are welded by application of a high energy beam, and a groove is provided on the outer peripheral side of the countersunk hole.

Growing community of inventors

Hyogo, Japan

Shinichirou Yoshida