Sanyo Electric Co., Ltd.

Mitsubishi Chemical Corporation

Shin-etsu Chemical Co., Ltd.

Santo Electric Co., Ltd.

Maruo Kamino

Ryuji Ohshita

Noriyuki Tamura

Shin Fujitani

Atsushi Fukui

Taizou Sunano

Masahisa Fujimoto

Seiji Yoshimura

Hiroshi Minami

Koji Nishio

Hiroshi Nakajima

Toshiyuki Nohma

Hiroyuki Fujimoto

Shigeki Matsuta

Daizo Jito

Taeko Ota

Katsunobu Sayama

Hidekazu Yamamoto

Taizo Sunano

Hiromasa Yagi

Toyoki Fujihara

Takashi Okamoto

Minoru Kotato

Yoshinori Kida

Hisaki Tarui

Yasuyuki Kusumoto

Masahiro Imanishi

Yoshio Kato

Youichi Ohashi

Kouhei Tuduki

Toshikazu Yoshida

Mariko Torimae

Nobuhiro Nishiguchi

Shiori Nakamizo

Masahiro Iyori

Toshio Yanagida

Yasuo Takano

Shouichirou Sawa

Makoto Uesugi

Ikuo Yonezu

Kenichi Shibata

Tetsuo Nakanishi

Hiroshi Kurokawa

Yoichi Domoto

Makoto Ue

Koichiro Watanabe

Kousuke Takeuchi

Masahiro Takehara

Kei Kobayashi

Toshiharu Tanaka

Takuya Sunagawa

Shouichiro Sawa

Nobuhiro Sakitani

Toshiaki Yokoo

Hiroko Sanda

Akira Ichihashi

Shoichiro Sawa

Provided is a lithium secondary battery in which negative-electrode active material particles containing silicon and/or a silicon alloy are used and which prevents the occurrence of breakage of a binder itself and peel-off of the binder at the interfaces with the negative-electrode active material and the negative-electrode current collector and has a high energy density and an excellent cycle characteristic. The lithium secondary battery includes: a negative electrode in which a negative-electrode active material layer including negative-electrode active material particles containing silicon and/or a silicon alloy and a binder is formed on a surface of electrically conductive metal foil serving as a negative-electrode current collector; a positive electrode; and a nonaqueous electrolyte, wherein the binder contains a polyimide resin including a crosslinked structure formed by imidization of a hexavalent or higher-valent carboxylic acid or an anhydride thereof with a diamine.

Lithium secondary battery and method for manufacturing the same

Provided is a nonaqueous electrolyte secondary battery which, even in the case of using a low-viscosity solvent having a narrow potential window, can increase the electrochemical stability of the nonaqueous electrolyte solution and suppress side reactions of the nonaqueous electrolyte solution during charge and discharge to reduce the degradation of the battery characteristics and has an excellent storage characteristic in high-temperature environments and a nonaqueous electrolyte solution for the nonaqueous electrolyte secondary battery. The nonaqueous electrolyte secondary battery includes: a positive electrode containing a positive-electrode active material; a negative electrode containing a negative-electrode active material; and a nonaqueous electrolyte solution containing a solute dissolved in a nonaqueous solvent, wherein the nonaqueous electrolyte solution further contains benzotrifluoride and a diisocyanate compound and the content of benzotrifluoride is 5% by volume or more in the nonaqueous electrolyte solution except the solute.

Non-aqueous electrolyte secondary battery, and non-aqueous electrolyte solution for non-aqueous electrolyte secondary battery

A nonaqueous electrolyte secondary battery includes a positive electrode having a positive-electrode active material, a negative electrode having a negative-electrode active material, and a nonaqueous electrolytic solution having a nonaqueous solvent dissolving a solute. The negative-electrode active material includes powdered silicon and/or a silicon alloy, the nonaqueous electrolytic solution includes additives composed of at least one fluorinated lithium phosphate selected from the group consisting of lithium monofluorophosphate, lithium difluorophosphate, and lithium trifluorophosphate and a diisocyanate compound, and the nonaqueous solvent includes a chain carbonate compound.

Nonaqueous electrolyte secondary battery and nonaqueous electrolytic solution for nonaqueous electrolyte secondary battery

The present invention is made to improve charge-discharge cycle performances under high temperature environment in a non-aqueous electrolyte secondary battery using a negative electrode containing a negative electrode active material of particulate silicon and/or silicon alloy and a binding agent. A non-aqueous electrolyte secondary battery according to the present invention includes a positive electrode, a negative electrode, a separator, and a non-aqueous electrolyte, wherein the negative electrode includes a negative electrode active material containing particulate silicon and/or silicon alloy and a binding agent, and the non-aqueous electrolyte contains fluorinated cyclic carbonate and a prescribed diisocyanate compound, and when Li storage volume per unit area of the negative electrode of the non-aqueous electrolyte secondary battery under charging condition is determined as A and the theoretical maximum Li storage volume per unit area of the negative electrode is determined as B, a utilizing rate (%) of negative electrode which is expressed by (A/B)&#xd7;100 is 45% or less.

Non-aqueous electrolyte secondary battery

This invention provides a negative electrode material for a rechargeable battery with a nonaqueous electrolyte, characterized in that the negative electrode material contains polycrystalline silicon particles as an active material, the particle diameter of crystallites of the polycrystalline silicon is not less than 20 nm and not more than 100 nm in terms of a crystallite size determined by the Scherrer method from the full width at half maximum of a diffraction line attributable to Si (111) around 2&#x3b8;=28.4&#xb0; in an x-ray diffraction pattern analysis, and the true specific gravity of the silicon particles is 2.300 to 2.320.

Negative electrode material for nonaqueous electrolyte secondary battery

A rechargeable lithium battery including a negative electrode made by depositing a noncrystalline thin film composed entirely or mainly of silicon on a current collector, a positive electrode and a nonaqueous electrolyte, characterized in that said nonaqueous electrolyte contains carbon dioxide dissolved therein.

Lithium secondary battery and method for producing same

A method of charging and discharging a lithium secondary battery in which a negative electrode comprises an active material including silicon provided on a current collector which is a metal which does not form an alloy with lithium. The method is characterized in that the lithium secondary battery is charged and discharged within a range of state of charge (SOC) at which no peak corresponding to a compound of lithium and silicon is observed in an X-ray diffraction pattern during charging using CuK-radiation as the X-ray source.

Method of charging and discharging lithium secondary battery and lithium secondary battery

A lithium secondary battery contains a negative electrode binder containing a polyimide resin having a structure represented by the following chemical formula (1), and the polyimide resin having a molecular weight distribution such that the weight ratio of a polyimide resin having a molecular weight of less than 100,000 and a polyimide resin having a molecular weight from 100,000 to less than 200,000 is from 50:50 to 90:10: where n is an integer equal to or greater than 1, and R is a functional group represented by the following chemical formula (2) or (3): 

Lithium secondary battery and method of manufacturing the same

A lithium secondary battery of the present invention comprises a positive electrode formed by disposing a positive-electrode mixture layer containing a positive-electrode active material and a positive-electrode binder, on a surface of a positive-electrode current collector; a negative electrode formed by sintering a negative-electrode mixture layer containing a negative-electrode binder and a negative-electrode active material containing silicon and/or a silicon alloy, disposed on a surface of a negative-electrode current collector; a separator disposed between the positive electrode and the negative electrode; and a nonaqueous electrolyte; wherein an electrode unit obtained by setting the positive electrode and the negative electrode opposed to each other through the separator and rolling them in spirally rolled state is placed in a cylindrical battery container and wherein a curvature radius of the negative-electrode mixture layer opposed to the positive-electrode mixture layer through the separator in the spirally rolled state is 1.5 mm or larger.

A nonaqueous electrolyte secondary battery in which the decomposition of an electrolyte solution is reduced exhibits high coulombic efficiency and excellent charge and discharge cycle performance, and has high energy density. This nonaqueous electrolyte secondary battery includes a negative electrode that is formed by depositing a thin film of active material on a collector by a CVD method, sputtering, evaporation, thermal spraying, or plating, wherein the thin film of the active material can lithiate and delithiate and is divided into columns by cracks formed in the thickness direction, and the bottom of each column is adhered to the collector; a positive electrode that can lithiate and delithiate; and a nonaqueous electrolyte solution containing a lithium salt in a nonaqueous solvent. The electrolyte solution contains a compound expressed by a general formula (I).R-M=0&#x2003;&#x2003;(I)(wherein, Rs are alkyl groups optionally having a substituent, may be identical or different from one another, may be independent substituents, or may be bound together to form a ring; M is S or P; and n is 2 when M is S and is 3 when M is P).

Nonaqueous electrolyte solution for secondary battery and nonaqueous electrolyte secondary battery

A non-aqueous electrolyte secondary battery has a positive electrode (), a negative electrode (), a separator () interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte solution in which a solute is dissolved in a non-aqueous solvent. The negative electrode contains a negative electrode active material capable of alloying with lithium and the non-aqueous solvent of the non-aqueous electrolyte solution contains one ore more fluorinated cyclic carbonates and a carboxylic ester. In addition, the non-aqueous electrolyte solution contains a nitrile compound having a chain saturated hydrocarbon group having two or more carbon atoms.

Non-aqueous electrolyte secondary battery including an electrolyte containing a fluorinated cyclic carbonate and carboxylic ester as a solvent and a nitrile compound as an additive

A lithium ion secondary batteryincludes a spirally wound electrode assemblyand a cylindrical battery container. The spirally wound electrode assemblyincludes a negative electrode, a positive electrodeand a separator. The negative electrodeincludes negative-electrode active material layersandcontaining a negative-electrode active material capable of forming an alloy with lithium. The lithium ion secondary batteryincludes an urging part. The urging partis disposed in the center of and in contact with the spirally wound electrode assembly. The urging partis contractible in diameter. The urging partis configured to urge the spirally wound electrode assemblyradially outward at least when contracting in diameter.

Lithium ion secondary battery

A rechargeable lithium battery including a negative electrode made by sintering, on a surface of a conductive metal foil as a current collector, a layer of a mixture of active material particles containing silicon and/or a silicon alloy and a binder, a positive electrode and a nonaqueous electrolyte, characterized in that the nonaqueous electrolyte contains carbon dioxide dissolved therein.

Lithium secondary battery including a negative electrode which is a sintered layer of silicon particles and/or silicon alloy particles and a nonaqueous electrolyte containing carbon dioxide dissolved therein and method for producing same

A lithium secondary battery has a wound electrode assembly (). The wound electrode assembly () has a negative electrode () having a negative electrode active material layer containing a negative electrode active material capable of alloying with lithium and having a filling density of 2.0 g/cc or less, a positive electrode () having a positive electrode active material layer containing a positive electrode active material made of a transition metal composite oxide, a separator () disposed between the positive and negative electrodes and having a penetration resistance of 500 g or greater, and a cylindrical hollow space () at a winding axis and in the vicinity thereof, wherein the positive electrode (), the negative electrode (), and the separator () are spirally wound. A columnar center pin () having a diameter of from 75% to 95% of the diameter of the hollow space is disposed in the hollow space.

Lithium secondary battery

A lithium secondary battery includes a negative electrode, a positive electrode, and a non-aqueous electrolyte. The negative electrode includes a negative electrode current collector () having an irregular surface and a negative electrode active material layer () formed on the surface. In the lithium secondary battery, the negative electrode active material layer () is composed of a material that alloys with Li; thickness of the negative electrode active material layer () (&#x3bc;m)/10-point mean surface roughness Rz of the negative electrode current collector () (&#x3bc;m) is in the range of from 0.5 to 4; and tensile strength of the negative electrode current collector () (N/mm) at 25&#xb0; C.&#xd7;the negative electrode current collector base thickness (mm)/thickness of the negative electrode active material layer () (&#x3bc;m) on one side of current collector is 2 or greater.

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Kobe, Japan

Maruo Kamino