Abstract: Provided is a nonaqueous electrolyte capable of suppressing swelling of an energy storage device caused by repeated charge-discharge, an energy storage device including the nonaqueous electrolyte, and a method for producing the energy storage device. One aspect of the present invention is a nonaqueous electrolyte which is used for an energy storage device and contains halogenated toluene and halogenated nitrotoluene. Another aspect of the present invention is an energy storage device including the nonaqueous electrolyte. Another aspect of the present invention is a method for producing an energy storage device, which uses the nonaqueous electrolyte.

Abstract: An object of the present invention is to provide a nonaqueous electrolyte secondary battery including a monofluorotoluene-containing nonaqueous electrolyte with an improved overcharge-preventing effect. In a monofluorotoluene-containing nonaqueous electrolyte, when a specific fluorophosphate compound is contained, the overcharge-preventing effect of the monofluorotoluene can be improved. As a result, in the overcharged state of a nonaqueous electrolyte secondary battery including the monofluorotoluene-containing nonaqueous electrolyte, an increase in the battery surface temperature can be suppressed.

Abstract: A nonaqueous electrolyte secondary battery including a positive electrode having a positive active material, and an electrolyte, wherein a positive electrode potential at the time of charging is 3.7 V or less with respect to a lithium metal potential, and the electrolyte contains a cyclic sulfate compound having a specific structure.

Abstract: An object of the present invention is to provide a nonaqueous electrolyte secondary battery including a monofluorotoluene-containing nonaqueous electrolyte with an improved overcharge-preventing effect. In a monofluorotoluene-containing nonaqueous electrolyte, when a specific fluorophosphate compound is contained, the overcharge-preventing effect of the monofluorotoluene can be improved. As a result, in the overcharged state of a nonaqueous electrolyte secondary battery including the monofluorotoluene-containing nonaqueous electrolyte, an increase in the battery surface temperature can be suppressed.

Abstract: A non-aqueous electrolyte secondary battery comprises a positive electrode, a negative electrode, a separator and a non-aqueous electrolyte and an insulating layer is formed between the positive electrode and the negative electrode, wherein the non-aqueous electrolyte contains a cyclic sulfate compound having a specific structure or a cyclic disulfonate compound having a specific structure.

Abstract: A nonaqueous electrolyte secondary battery including a positive electrode having a particulate positive active material, and an electrolyte, wherein the positive active material contains a nickel-containing lithium transition metal oxide and has an average particle size of 3 to 15 ?m, and the electrolyte contains a cyclic sulfate compound having a specific structure.

Abstract: A nonaqueous electrolyte secondary battery including a positive electrode having a positive active material, and an electrolyte, wherein a positive electrode potential at the time of charging is 3.7 V or less with respect to a lithium metal potential, and the electrolyte contains a cyclic sulfate compound having a specific structure.

Abstract: Provided is a nonaqueous electrolyte secondary battery comprising a nonaqueous electrolyte. A lithium phosphate compound and a cyclic sulfone compound are contained in the nonaqueous electrolyte. The lithium phosphate compound is contained in an amount greater than 0% by mass and less than or equal to 4.0% by mass relative to the whole mass of the nonaqueous electrolyte. The cyclic sulfone compound is contained in an amount greater than 0% by mass and less than or equal to 3.0% by mass relative to the whole mass of the nonaqueous electrolyte. The lithium phosphate compound comprises lithium difluoro(bisoxalato) phosphate and lithium tetrafluoro(oxalato) phosphate.