Nec Corporation

Nec C Orporation

Nec Energy Devices, Ltd.

Ikiko Shimanuki

Hitoshi Ishikawa

Noboru Yoshida

Daisuke Kawasaki

Takehiro Noguchi

Takuya Hasegawa

Kazuaki Matsumoto

Shinsaku Saitho

Makihiro Otohata

Takeshi Azami

Suguru Tamai

Jiro Iriyama

Shinako Kaneko

Yuukou Katou

A purpose of the present invention is to provide a lithium ion secondary battery having improved battery characteristics. The lithium ion secondary battery according to the present invention comprises a negative electrode comprising a negative electrode active material comprising a silicon material and an electrolyte solution comprising an electrolyte solvent comprising an open chain sulfone compound, a fluorinated cyclic carbonate and an open chain carbonate and a supporting salt comprising LiN(FSO).

Lithium ion secondary battery

A lithium ion secondary battery having high energy density and being excellent in cycle characteristics is provided. The present invention relates to a lithium ion secondary battery comprising: a negative electrode active material comprising a material comprising silicon as a constituent element; and an electrolyte solution comprising: a non-aqueous solvent comprising a fluorinated ether compound, an open-chain sulfone compound, and a cyclic carbonate compound, and a supporting salt comprising LiPF, lithium bis(fluorosulfonyl)imide, and lithium bis(oxalato)borate (LiBOB); wherein the content of LiBOB in the electrolyte solution is 0.2 mass % or more.

The present invention relates to an electrolyte solution comprising a supporting salt, a nonaqueous solvent containing a compound having a viscosity of 1.0 mPa-s or less in an amount of more than 50% by volume in the nonaqueous solvent, and a halogenated cyclic acid anhydride. According to the present invention, an electrolyte solution capable of suppressing gas generation is provided.

Nonaqueous electrolyte solution and secondary battery

A purpose of one embodiment of the present invention is to provide a lithium ion secondary battery that has improved life-span characteristics. The first lithium ion secondary battery of the present invention comprises an electrolyte solution comprising a sulfone compound, a fluorinated ether compound and LiN(FSO), and a negative electrode comprising a silicon material, wherein a content of LiN(FSO)in the electrolyte solution is more than 5 weight % and 20 weight % or less.

The present invention relates to a lithium secondary battery having a positive electrode comprising a positive electrode active material capable of absorbing and releasing lithium ions, a negative electrode comprising a negative electrode active material capable of absorbing and releasing lithium ions, and an electrolyte solution, wherein a positive electrode surface detection component comprises at least one negative secondary ion peak selected from CHSOand CHSO, and further comprises a negative secondary ion peak of SO&#x2014;, wherein the positive electrode surface detection component is detected when a primary ion is irradiated on the surface of the positive electrode active material by a Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) method. According to the present invention, it is possible to provide a lithium secondary battery having excellent cycle characteristics.

Lithium secondary battery and manufacturing method therefor

When the particle size of a silicon material used for a negative electrode active material are small, a large surface area thereof easily causes a side reaction between the active material and an electrolyte solvent to occur, and the cycle characteristics of a lithium ion secondary battery decrease. In order to improve the cycle characteristics, a lithium ion secondary battery according to the present invention is characterized in comprising a negative electrode comprising a material comprising silicon as a constituent element and a polyacrylic acid, and an electrolyte solution comprising a fluoroethylene carbonate, wherein the 50% particle size of the material comprising silicon as a constituent element is 2 &#x3bc;m or less.

A lithium ion secondary battery excellent in cycle characteristics, comprising a high capacity negative electrode comprising a metal and/or a metal oxide as an active material is provided. The present invention relates to a lithium ion secondary battery comprising a positive electrode, a negative electrode, and an electrolyte solution, wherein the negative electrode comprises (a) a carbon material that can absorb and desorb lithium ions; at least one selected from the group consisting of (b) lithium metal and metals that can be alloyed with lithium and (c) metal oxides that can absorb and desorb lithium ions; and a polyacrylic acid, and the electrolyte solution comprises at least one disulfonic acid ester.

The present invention relates to an electrolytic solution comprising a cyclic disulfonic acid ester represented by the specific formula and a cyclic dicarboxylic acid ester represented by the specific formula, and the secondary battery using the same. According to the present invention, the electrolytic solution which can improve a cycle characteristics in a secondary battery and a secondary battery using the same can be provided.

Electrolytic solution and secondary battery

The present invention relates to an electrolytic solution comprising a cyclic dicarboxylic acid ester represented by the specific formula, and the secondary battery comprising the same. According to the present invention, the electrolytic solution comprising an additive which can improve a characteristics in a secondary battery and a secondary battery comprising the same can be provided.

It is an object of the present invention to provide an electrolytic solution capable of suppressing gas generation. The present exemplary embodiment is an electrolytic solution comprising a supporting salt, a nonaqueous solvent that dissolves the supporting salt, a cyclic sulfonic acid ester compound represented by predetermined formula (1), and an acid anhydride. According to the exemplary embodiment, an electrolytic solution capable of suppressing gas generation can be provided.

The present invention provides a lithium ion secondary battery comprising: a positive electrode; a negative electrode comprising a negative electrode active material comprising at least one carbon material selected from the group consisting of a natural graphite, an artificial graphite, a non-graphitizable carbon and a graphitizable carbon; and an electrolyte solution comprising a specific cyclic disulfonate ester compound and an acid anhydride.

Disclosed is an electrolyte solution for lithium secondary batteries, including a cyclic sulfonic acid ester represented by the general formula (1): wherein, in the general formula (1), Rand Reach independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, halogen or an amino group with the proviso that Rand Rdo not represent hydrogen atoms at the same time; and Rrepresents methylene which may be substituted with fluorine. Batteries using this electrolyte solution are excellent in battery properties and storage characteristics.

Electrolyte solution for secondary batteries, and secondary battery using same

The present invention relates to a gel electrolyte comprising a cyclic sulfonic acid ester represented by formula (1). According to the present invention, it is possible to provide a gel electrolyte capable of suppressing the self-discharge of a polymer secondary battery, and a polymer secondary battery using the gel electrolyte. wherein Rand Rare each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen group or an amino group with the proviso that Rand Rare not hydrogen atoms at the same time; Rrepresents a linkage group selected from the group consisting of an alkylene group having 1 to 5 carbon atoms, a carbonyl group, a sulfonyl group, a fluoroalkylene group having 1 to 6 carbon atoms, and a divalent group having 2 to 6 carbon atoms in which alkylene units or fluoroalkylene units are bonded through an ether group.

Gel electrolyte and polymer secondary battery using same

It is an object of the present invention to provide a method for producing a secondary battery in which water in the outer package can be removed even when the secondary battery includes an electrolytic solution containing a halogen-containing compound. The present exemplary embodiment is a method for producing a secondary battery including an electrolytic solution containing a supporting salt, a nonaqueous solvent, and a halogen-containing compound, an electrode assembly including a negative electrode and a positive electrode, and an outer package, the method including (1) disposing a first solution containing at least the supporting salt and the nonaqueous solvent, and the electrode assembly in the outer package; (2) charging the electrode assembly; (3) emitting from the outer package a gas generated by the charge; and (4) injecting a second solution including at least the halogen-containing compound into the outer package after the gas is emitted, wherein the first solution does not contain the halogen-containing compound, and the electrolytic solution includes the first solution and the second solution.

Method for producing secondary battery

A nonaqueous electrolyte solution secondary battery having an electrode element having a positive electrode and a negative electrode disposed so as to face each other, a nonaqueous electrolyte solution, and an outer package housing the electrode element and the nonaqueous electrolyte solution, wherein the nonaqueous electrolyte solution contains a cyclic sulfonic acid ester represented by the general formula (1), and a positive electrode active material in the positive electrode is a mixture of a lithium manganese composite oxide having a spinel structure and a lithium transition metal composite compound having a layered rock salt structure. wherein, in the formula (1), Rand Rare each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen group or an amino group with the proviso that Rand Rare not hydrogen atoms at the same time; Rrepresents a linkage group selected from the group consisting of an alkylene group having 1 to 5 carbon atoms, a carbonyl group, a sulfonyl group, a fluoroalkylene group having 1 to 6 carbon atoms, and a divalent group having 2 to 6 carbon atoms in which alkylene units or fluoroalkylene units are bonded through an ether group.

Growing community of inventors

Tokyo, Japan

Ikiko Shimanuki