Sony Corporation

Murata Manufacturing Co., Ltd.

Mashio Shibuya

Kazuhito Hatta

Yusuke Suzuki

Tomitaro Hara

Shuji Goto

Kenichi Kawase

Hiroyuki Akashi

Akinori Kita

Tsuyonobu Hatazawa

Yasuharu Ujiie

Goro Shibamoto

Fumiko Hara

Yusuke Fujishige

A method of forming a package is provided and includes providing two laminate edge portions of the package, each of which includes a foil layer between first and second resin layers; and welding together the respective first resin layers at a first position spaced apart from the edges while not welding the respective first resin layers at the edges, wherein the edge portions include edges from which electrode terminals extend such that portions of the electrode terminals are exposed beyond the edges, and wherein the edge portions are between a sealing portion and exposed portions of positive and negative electrode terminals.

Battery cell and exterior packaging material

Method of forming a package

Battery cell and laminate film

A cell in which thermal welding of a laminate packaging is performed so that the thickness of a thermal welded portion including an electrode terminal is larger than that of a thermal welded portion including no electrode terminal.

Cell

A cell is provided. The cell includes a cell element including a positive electrode, a negative electrode, an electrolyte and a laminate film including an exterior layer, a metal layer, an interior layer, and a welded layer formed of the interior layer; wherein a thickness of the welded layer is larger than 5 &#x3bc;m in a flat portion of the interior layer, wherein the welded layer increases in thickness from the flat portion to an end portion of the welded layer, and wherein when a thickness of the laminate film is t, a thickness of the interior layer is p and a thickness of the laminate film in the welded layer is t1, a following equation is satisfied: t&#xd7;2&#x2212;p&#xd7;2+5&#x3c;t1&#x3c;t&#xd7;2&#x2212;5 (&#x3bc;m).

A battery is provided including a battery element including a positive electrode, a negative electrode, and an electrolyte; and a laminate film for packaging the battery element, wherein the laminate film includes a first portion including a first portion thickness, a second portion including a second portion thickness and a third portion including a third portion thickness, wherein the second portion is located between the first portion and the third portion, wherein a first side of the third portion is not in contact with a second side of the third portion, and the third portion thickness includes a thickness of the first side and the second side of the third portion, wherein the first portion thickness of at least a part of the first portion is thinner than the second portion thickness, wherein the third portion thickness of at least a part of the third portion is thicker than the first portion thickness, and wherein the third portion includes an edge portion of the laminate film.

Battery

A nonaqueous electrolyte secondary battery includes a positive electrode; a negative electrode; and a nonaqueous electrolyte, wherein the negative electrode has a negative electrode mixture layer including a negative electrode active material; a polymer containing vinylidene fluoride as a repeating unit; a polymer containing acrylonitrile as a repeating unit; and a vapor-grown carbon fiber; and the nonaqueous electrolyte contains a fluorocarbon based polymer compound.

Negative electrode comprising vapor grown carbon fiber and polymer materials and nonaqueous electrolyte secondary battery

A highly safety cell is provided in which short-circuiting is unlikely to occur. In order to prevent short-circuiting, for example, burrs generated when a laminate film used as an exterior packaging material is cut are prevented from penetrating an interior resin layer of the laminate film. When an electrode terminal extension side of the laminate film is thermal welded, heating and compression are performed by a heater head on a part of the laminate film apart from the edge portion thereof so that the thickness of the above edge portion is larger than that of a thermal welded portion. In addition, thermal welding is performed so that the thickness of a thermal welded portion including an electrode terminal is larger than that of a thermal welded portion including no electrode terminal, and as a result, short-circuiting can be more effectively prevented.

A battery capable of obtaining the superior battery performance is provided. An electrolyte is a gel electrolyte containing an electrolytic solution and a polymer compound. The polymer compound contains a ternary system copolymer containing vinylidene fluoride, hexafluoropropylene, and monomethylmaleic acid ester as a component. The copolymerization amounts of hexafluoropropylene and monomethylmaleic acid ester in the ternary system copolymer are respectively in the range from 4 wt % to 7.5 wt %, and in the range from 0.3 wt % to 2 wt %. Further, the weight average molecular weight of the ternary system copolymer is in the range from 0.6 million to 1.5 million. The liquid retaining characteristics of the electrolyte are improved. Therefore, the contact characteristics of the electrolyte to a cathode, an anode, and a separator are improved.

The present invention uses a mixture of spherical carbonaceous materials having different average particle sizes as an anode active material in an anode composite mixture layer of an anode. The spherical carbonaceous material of large particle size decreases the reaction with non-aqueous electrolyte solution to suppress the decrease in battery capacity, form clearances having suitable sizes in the anode composite mixture layer, and retain the non-aqueous electrolyte solution. The clearances in the anode composite mixture layer are efficiently filled with the carbonaceous material of small particle size while spaces capable of suitably retaining the non-aqueous electrolyte solution are left unfilled. Thus, the volume density of the anode composite mixture layer is improved and the battery capacity is increased. Accordingly, energy density can be increased without deteriorating battery characteristics.

Nonaqueous electrolyte battery

A gel electrolyte and a gel electrolyte battery are provided. The gel electrolyte includes a matrix polymer; a nonaqueous solvent; and an electrolytic solution having an electrolyte salt containing lithium dissolved in the nonaqueous solvent, in which the matrix polymer is swollen with the electrolytic solution. The matrix polymer comprises polyvinylidene fluoride copolymerized with at least hexafluoropropylene in an amount of 3 wt % or more and 7.5 wt % or less. The nonaqueous solvent comprises ethylene carbonate; and at least one solvent selected from the group consisting of dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, ethylpropyl carbonate, ethyl butyl carbonate, and dipropyl carbonate. The content of the ethylene carbonate in the nonaqueous solvent is 15 wt % or more and 55 wt % or less, and the total content of the at least one solvent in the nonaqueous solvent is 30 wt % or more and 85 wt % or less.

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Fukushima, Japan

Mashio Shibuya