Abstract: 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(FSO2)2.

Abstract: 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 LiPF6, 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.

Abstract: 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.

Abstract: 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(FSO2)2, and a negative electrode comprising a silicon material, wherein a content of LiN(FSO2)2 in the electrolyte solution is more than 5 weight % and 20 weight % or less.

Abstract: 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 CH3S2O6? and CHS2O4?, and further comprises a negative secondary ion peak of SO3—, 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.

Abstract: 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 ?m or less.

Abstract: 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(FSO2)2.

Abstract: 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.

Abstract: 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 LiPF6, 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.

Abstract: 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.

Abstract: 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.

Abstract: A lithium ion secondary battery having high energy density and excellent cycle characteristics is provided. The present invention relates to a lithium ion secondary battery comprising a negative electrode comprising a negative electrode active material comprising more than 25% by weight of a silicon alloy and a non-aqueous electrolyte solution comprising more than 10% by weight of a compound represented by LiN(SO2CnF2n+1)2 (wherein n is an integer of 0 or more) and 10% by weight or more of fluoroethylene carbonate (FEC).

Abstract: 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.

Abstract: 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 ?m or less.

Abstract: 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.

Abstract: 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.

Abstract: 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), R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, halogen or an amino group with the proviso that R1 and R2 do not represent hydrogen atoms at the same time; and R3 represents methylene which may be substituted with fluorine. Batteries using this electrolyte solution are excellent in battery properties and storage characteristics.

Abstract: A negative electrode for a lithium ion secondary battery is disclosed, which comprises, as active materials, (a) at least one material selected from metals capable of forming an alloy with lithium and metal oxides capable of absorbing and desorbing lithium ions (hereinafter referred to as metal and/or metal oxide), and (b) a surface-coated carbon material capable of absorbing and desorbing lithium ions; wherein, an average value of circularity of the metal and/or metal oxide particles defined by following formula (1) is 0.78 or more; Circularity=4?S/L2 ??(1) wherein S is an area of a projected image of particle and L is a circumferential length of the projected image of particle. The lithium ion secondary battery having this electrode has improved cycle characteristics.

Abstract: 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 R1 and R2 are 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 R1 and R2 are not hydrogen atoms at the same time; R3 represents 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.

Abstract: 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.