Electrolyte, battery, battery pack, electronic apparatus, electric vehicle, power storage apparatus, and power system

1. An electrolyte for a lithium-ion secondary battery, comprising:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a first ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

2. The electrolyte for the lithium-ion secondary battery according to claim 1 , wherein

a content of the at least one of compounds represented by the formula (2) is not less than 0.001% by mass and not more than 50% by mass with respect to a total mass of the electrolyte.

3. The electrolyte for the lithium-ion secondary battery according to claim 1 , further comprising:

at least one of a halogenated carbonic acid ester, an unsaturated cyclic carbonic acid ester, a sultone, a dinitrile compound, an isocyanate compound, a lithium difluorophosphate, a lithium monofluorophosphate, and a lithium difluoro oxalate borate.

4. The electrolyte for the lithium-ion secondary battery according to claim 3 , wherein:

the halogenated carbonic acid ester is at least one of compounds represented by a formula (3),

the unsaturated cyclic carbonic acid ester is at least one of compounds represented by a formula (5),

the sultone is at least one of compounds represented by a formula (6),

the dinitrile compound is at least one of compounds represented by a formula (7), and

the isocyanate compound is hexamethylene diisocyanate,

(in the formula (3), R11, R12, R13, and R14 each independently represents a hydrogen group, a halogen group, a monovalent hydrocarbon group, or a monovalent halogenated hydrocarbon group, and at least one of R11, R12, R13, and R14 is a halogen group or a monovalent halogenated hydrocarbon group),

(in the formula (5), R21 and R22 each independently represents a hydrogen group, a halogen group, a monovalent hydrocarbon group, or a monovalent halogenated hydrocarbon group),

(in the formula (6), Rn is a divalent hydrocarbon group having n carbon atoms, a second ring being formed by the divalent hydrocarbon group together with S (sulfur) and O (oxygen), n represents 2 to 5, and the second ring contains an unsaturated double bond),

NC-R31-CN  (7)

(in the formula (7), R31 is a divalent hydrocarbon group or a divalent halogenated hydrocarbon group which contains an oxygen atom or a sulfur atom).

5. The electrolyte for the lithium-ion secondary battery according to claim 1 , further comprising:

a polymer compound; and

particles.

6. A lithium-ion secondary battery, comprising:

a positive electrode;

a negative electrode; and

an electrolyte, wherein

the electrolyte includes:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

7. The lithium-ion secondary battery according to claim 6 , wherein

the negative electrode contains, as a negative electrode active material, at least one of a simple substance of silicon, an alloy of silicon, a compound of silicon, and a lithium metal.

8. The lithium-ion secondary battery according to claim 6 , wherein

open circuit voltage in a fully charged state per pair of positive and negative electrodes is not less than 4.20 V and not more than 4.50 V.

9. A battery pack, comprising:

a lithium-ion secondary battery;

a control unit that controls the lithium-ion secondary battery; and

an exterior that houses the lithium-ion secondary battery,

wherein the lithium-ion secondary battery includes:

a positive electrode,

a negative electrode, and

an electrolyte, wherein

the electrolyte includes:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

10. An electronic apparatus, comprising a lithium-ion secondary battery, wherein:

the electronic apparatus receives power supply from the lithium-ion secondary battery, and

the lithium-ion secondary battery includes:

a positive electrode,

a negative electrode, and

an electrolyte, wherein

the electrolyte includes:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

11. An electric vehicle, comprising:

a lithium-ion secondary battery;

a converting apparatus that receives supply of power from the lithium-ion secondary battery and converts the received power into a driving force for the electric vehicle; and

a control apparatus that performs information processing relating to vehicle control based on information on the lithium-ion secondary battery,

wherein the lithium-ion secondary battery includes:

a positive electrode,

a negative electrode, and

an electrolyte, wherein

the electrolyte includes:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

12. A power storage apparatus, comprising a lithium-ion secondary battery, wherein:

the power storage apparatus supplies power to an electronic apparatus connected to the lithium-ion secondary battery, and

the lithium-ion secondary battery includes:

a positive electrode,

a negative electrode, and

an electrolyte, wherein

the electrolyte includes:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

13. The power storage apparatus according to claim 12 , further comprising:

a power information control apparatus that transmits/receives a signal to/from another apparatus via a network,

wherein the power storage apparatus controls, based on information received by the power information control apparatus, charge and discharge of the lithium-ion secondary battery.

14. A power system, comprising:

circuitry that receives power supply from a lithium-ion secondary battery, or supplies power from a power generation apparatus or a power network to the lithium-ion secondary battery,

wherein the lithium-ion secondary battery includes:

a positive electrode,

a negative electrode, and

an electrolyte, wherein

the electrolyte includes:

a non-aqueous solvent,

an electrolyte salt, and

at least one of compounds represented by a formula (2),

(in the formula (2), A2 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A2 has a number of carbon atoms from 3 to 5, a ring being formed with A2, O (oxygen), and P (phosphorus) and R2 and R3 each independently represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).

15. The electrolyte for the lithium-ion secondary battery according to claim 1 , further comprising:

at least one of compounds represented by a formula (1),

(in the formula (1), A1 represents a divalent saturated hydrocarbon group, a divalent unsaturated hydrocarbon group, a divalent halogenated saturated hydrocarbon group, or a divalent halogenated unsaturated hydrocarbon group, A1 has a number of carbon atoms from 3 to 5, a third ring being formed with A1, O (oxygen), and P (phosphorus) and R1 represents a monovalent saturated hydrocarbon group, a monovalent unsaturated hydrocarbon group, a monovalent aromatic hydrocarbon group, a monovalent halogenated saturated hydrocarbon group, a monovalent halogenated unsaturated hydrocarbon group, or a monovalent halogenated aromatic hydrocarbon group).