Electrolyte for secondary battery, secondary battery, battery pack, electric vehicle, electric power storage system, electric tool and electronic device

An electrolytic solution for a secondary battery, wherein

• the electrolytic solution contains a solvent and an electrolyte salt, the solvent containing ethylene carbonate,
• a content of the electrolyte salt is from 0.8 mol/kg to 2.0 mol/kg both inclusive,
• a content of the ethylene carbonate in the solvent is from 10 wt % to 30 wt % both inclusive,
• a ratio M2/M1 of a number M2 of moles of the ethylene carbonate to a number M1 of moles of the electrolyte salt is from 0.4 to 2.4 both inclusive, and
• the electrolytic solution contains at least one of sulfone compounds represented by formulas (1), (2), and (3):
• where R1 is any one of an alkyl group, a cycloalkyl group, and a monovalent group in which two or more of the alkyl group and the cycloalkyl group are bound, R2 is any one of a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, and a monovalent binding group in which two or more of the monovalent saturated hydrocarbon group and the monovalent unsaturated hydrocarbon group are bound, Y is a divalent unsaturated hydrocarbon group, and X is an alkynlene group or an arylene group.

A battery pack comprising:

• a secondary battery;
• a controller that controls an operation of the secondary battery;
• and
• a switch section that switches the operation of the secondary battery in response to an instruction of the controller;
• the secondary battery including:
• a positive electrode,
• a negative electrode, and
• an electrolytic solution,
• wherein (A) the electrolytic solution contains a solvent and an electrolyte salt, the solvent containing ethylene carbonate, (B) a content of the electrolyte salt is from 0.8 mol/kg to 2.0 mol/kg both inclusive, (C) a content of the ethylene carbonate in the solvent is from 10 wt % to 30 wt % both inclusive, (D) a ratio M2/M1 of a number M2 of moles of the ethylene carbonate to a number M1 of moles of the electrolyte salt is from 0.4 to 2.4 both inclusive, and (E) the electrolytic solution contains at least one of sulfone compounds represented by formulas (1), (2), and (3):
• where R1 is any one of an alkyl group, a cycloalkyl group, and a monovalent group in which two or more of the alkyl group and the cycloalkyl group are bound, R2 is any one of a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, and a monovalent binding group in which two or more of the monovalent saturated hydrocarbon group and the monovalent unsaturated hydrocarbon group are bound, Y is a divalent unsaturated hydrocarbon group, and X is an alkynlene group or an arylene group.

An electric vehicle comprising:

• a secondary battery;
• a converter that converts electric power supplied from the secondary battery into a driving force;
• a driving unit that drives in response to the driving force;
• and
• a controller that controls an operation of the secondary battery,
• the secondary battery including:
• a positive electrode,
• a negative electrode, and
• an electrolytic solution,
• wherein (A) the electrolytic solution contains a solvent and an electrolyte salt, the solvent containing ethylene carbonate, (B) a content of the electrolyte salt is from 0.8 mol/kg to 2.0 mol/kg both inclusive, (C) a content of the ethylene carbonate in the solvent is from 10 wt % to 30 wt % both inclusive, (D) a ratio M2/M1 of a number M2 of moles of the ethylene carbonate to a number M1 of moles of the electrolyte salt is from 0.4 to 2.4 both inclusive, and (E) the electrolytic solution contains at least one of sulfone compounds represented by formulas (1), (2), and (3):
• where R1 is any one of an alkyl group, a cycloalkyl group, and a monovalent group in which two or more of the alkyl group and the cycloalkyl group are bound, and R2 is any one of a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, and a monovalent binding group in which two or more of the monovalent saturated hydrocarbon group and the monovalent unsaturated hydrocarbon group are bound, Y is a divalent unsaturated hydrocarbon group, and X is an alkynlene group or an arylene group.

A power storage system comprising:

• a secondary battery;
• at least one electric device that has a supply of electric power from the secondary battery;
• and
• a controller that controls the supply of the electric power to the electric device from the secondary battery;
• the secondary battery including:
• a positive electrode,
• a negative electrode, and
• an electrolytic solution,
• wherein (A) the electrolytic solution contains a solvent and an electrolyte salt, the solvent containing ethylene carbonate, (B) a content of the electrolyte salt is from 0.8 mol/kg to 2.0 mol/kg both inclusive, (C) a content of the ethylene carbonate in the solvent is from 10 wt % to 30 wt % both inclusive, (D) a ratio M2/M1 of a number M2 of moles of the ethylene carbonate to a number M1 of moles of the electrolyte salt is from 0.4 to 2.4 both inclusive, and (E) the electrolytic solution contains at least one of sulfone compounds represented by formulas (1), (2), and (3):
• where R1 is any one of an alkyl group, a cycloalkyl group, and a monovalent group in which two or more of the alkyl group and the cycloalkyl group are bound, and R2 is any one of a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, and a monovalent binding group in which two or more of the monovalent saturated hydrocarbon group and the monovalent unsaturated hydrocarbon group are bound, Y is a divalent unsaturated hydrocarbon group, and X is an alkynlene group or an arylene group.

A power tool comprising:

• a secondary battery;
• and
• a movable section that is supplied with electric power from the secondary battery;
• the secondary battery including:
• a positive electrode,
• a negative electrode, and
• an electrolytic solution
• wherein (A) the electrolytic solution contains a solvent and an electrolyte salt, the solvent containing ethylene carbonate, (B) a content of the electrolyte salt is from 0.8 mol/kg to 2.0 mol/kg both inclusive, (C) a content of the ethylene carbonate in the solvent is from 10 wt % to 30 wt % both inclusive, (D) a ratio M2/M1 of a number M2 of moles of the ethylene carbonate to a number M1 of moles of the electrolyte salt is from 0.4 to 2.4 both inclusive, and (E) the electrolytic solution contains at least one of sulfone compounds represented by formulas (1), (2), and (3):
• where R1 is any one of an alkyl group, a cycloalkyl group, and a monovalent group in which two or more of the alkyl group and the cycloalkyl group are bound, R2 is any one of a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, and a monovalent binding group in which two or more of the monovalent saturated hydrocarbon group and the monovalent unsaturated hydrocarbon group are bound, Y is a divalent unsaturated hydrocarbon group, and X is an alkynlene group or an arylene group.

An electronic device comprising a secondary battery as

• a power supply source,
• the secondary battery including:
• a positive electrode,
• a negative electrode, and
• an electrolytic solution
• wherein (A) the electrolytic solution contains a solvent and an electrolyte salt, the solvent containing ethylene carbonate, (B) a content of the electrolyte salt is from 0.8 mol/kg to 2.0 mol/kg both inclusive, (C) a content of the ethylene carbonate in the solvent is from 10 wt % to 30 wt % both inclusive, (D) a ratio M2/M1 of a number M2 of moles of the ethylene carbonate to a number M1 of moles of the electrolyte salt is from 0.4 to 2.4 both inclusive, and (E) the electrolytic solution contains at least one of sulfone compounds represented by formulas (1), (2), and (3):
• where R1 is any one of an alkyl group, a cycloalkyl group, and a monovalent group in which two or more of the alkyl group and the cycloalkyl group are bound, R2 is any one of a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, and a monovalent binding group in which two or more of the monovalent saturated hydrocarbon group and the monovalent unsaturated hydrocarbon group are bound, Y is a divalent unsaturated hydrocarbon group, and X is an alkynlene group or an arylene group.