CN116344942A - Electrolyte and battery - Google Patents

Abstract

The invention discloses an electrolyte and a battery, wherein the electrolyte comprises the following components: the electrolyte, the solvent, the first additive and the second additive, wherein the first additive is selected from at least one of structural formulas (1) to (4), and the second additive is selected from at least one of structural formulas (5) to (7). The first additive has high oxidation resistance, and the unsaturated double bonds contained in the first additive can be polymerized at the negative electrode to form an SEI protective film, so that the protective film inhibits the volume expansion of the silicon negative electrode. The second additive can form a polymeric film on the surface of the positive electrode under high voltage, so that the oxidation resistance of the electrolyte can be improved, a stable film layer is formed on the surface of the electrode under the combined action of the first additive and the second additive, the volume expansion of the electrode is restrained, the expansion stress is prevented from damaging the interface of the surface of the electrode, the contact between the electrolyte and the electrode material is blocked, the oxidation resistance of the electrolyte is improved, the performance stability of the battery under high voltage is improved, and the high-temperature storage and cycle performance of the battery is improved.

Description

Electrolyte and battery

Technical Field

The invention belongs to the technical field of batteries, and particularly relates to electrolyte and a battery.

Background

The lithium ion battery has the advantages of larger specific energy density, long cycle life and the like, so that the lithium ion battery is widely applied to various electronic products, is widely applied to electric vehicles, various electric tools and energy storage devices in recent years, and has higher requirements on the battery energy density along with the continuous increase of application fields and application scenes. A lithium ion battery is a rechargeable battery that operates primarily by virtue of movement of lithium ions between a positive electrode and a negative electrode. During charge and discharge, lithium ions are inserted and extracted back and forth between the two electrodes: during charging, lithium ions are deintercalated from the positive electrode and are intercalated into the negative electrode through electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true when discharging. The silicon-based material is expected to become a high specific energy lithium ion battery anode material because of high specific capacity and lower lithium intercalation potential, but the volume of the silicon-based anode can be greatly changed in the charge and discharge process, and the performance of the silicon-based anode is seriously influenced. At high voltages, the positive electrode material and the silicon negative electrode material in the battery are prone to volume expansion, and the stress can damage the interface of the electrode surface, resulting in degradation of the battery performance.

Disclosure of Invention

The embodiment of the invention aims to provide an electrolyte and a battery, which are used for solving the problem that a positive electrode material and a silicon negative electrode material in the battery are easy to expand in volume under high voltage, and stress can damage an interface of an electrode surface.

In a first aspect, an embodiment of the present invention provides an electrolyte, including:

electrolyte, solvent, first additive and second additive, the first additive is selected from at least one of structural formula (1) to structural formula (4),

wherein R is ₁ 、R ₂ And R is ₃ Each independently selected from C ₁ -C ₂₀ One of an alkane, a haloalkane, an aromatic hydrocarbon or a halogenated aromatic hydrocarbon;

the second additive is selected from at least one of structural formulas (5) to (7),

further, R ₁ 、R ₂ And R is ₃ Each independently selected from C substituted or unsubstituted with halogen ₁ -C ₂₀ C which is substituted or unsubstituted by halogen ₃ -C ₂₀ Cycloalkyl of (C), phenyl substituted or unsubstituted by halogen, biphenyl substituted or unsubstituted by halogen, C substituted or unsubstituted by halogen ₆ -C ₂₆ A phenylalkyl group, a fused ring aromatic hydrocarbon group substituted or unsubstituted with halogen.

Further, R ₁ 、R ₂ And R is ₃ Each independently selected from C substituted or unsubstituted with F ₁ -C ₅ C, substituted or unsubstituted by F ₃ -C ₅ Cycloalkyl, phenyl substituted or unsubstituted by F, C substituted or unsubstituted by F ₆ -C ₉ A phenylalkyl group of (C), a condensed ring aromatic hydrocarbon group substituted or unsubstituted with F.

Further, the first additive is selected from at least one of structural formulas 1-1 to 1-10,

further, the content of the first additive is 0.1-5.0% of the total mass of the electrolyte.

Further, the content of the second additive is 0.1-5.0% of the total mass of the electrolyte.

Further, the electrolyte includes:

at least one of lithium hexafluorophosphate, lithium difluorophosphate, lithium difluorooxalato borate, lithium bistrifluoromethylsulfonyl imide, lithium difluorobisoxalato phosphate, lithium tetrafluoroborate, lithium bisoxalato borate, lithium hexafluoroantimonate, lithium hexafluoroarsenate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium tris (trifluoromethylsulfonyl) methyl imide, and lithium bis (trifluoromethylsulfonyl) imide; and/or

The electrolyte further comprises: at least one of fluoroethylene carbonate, 1, 3-propane sultone and 1,3, 6-hexane trinitrile.

Further, the solvent includes: at least one of a carbonate and a carboxylate.

Further, the carbonate includes at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethylmethyl carbonate;

the carboxylic acid ester comprises at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl propionate, ethyl propionate, methyl butyrate and ethyl n-butyrate.

In a second aspect, an embodiment of the present invention provides a battery including:

the electrolyte described in the above examples.

The electrolyte of the embodiment of the invention comprises the following components: the electrolyte, the solvent, the first additive and the second additive, wherein the first additive is selected from at least one of structural formulas (1) to (4), and the second additive is selected from at least one of structural formulas (5) to (7). The first additive is a phosphorus-containing compound with unsaturated bonds, has high oxidation resistance, can absorb single-wire oxygen released by the positive electrode under high voltage and inhibit oxidative decomposition of a solvent, and the unsaturated double bonds contained in the first additive can be polymerized at the negative electrode to form an SEI protective film, so that the formed protective film can inhibit volume expansion of a silicon negative electrode and further prevent electrolyte from entering the negative electrode material to cause damage. The second additive is a thiophene structure containing single or multiple phosphate esters, the thiophene structure can be polymerized on the surface of the positive electrode, a polymerized film can be formed on the surface of the positive electrode by the second additive under high voltage, the contact between electrolyte and a positive electrode material can be effectively blocked, meanwhile, the contained phosphate ester groups can improve the oxidation resistance of the electrolyte, a stable film layer can be formed on the surface of the electrode under the combined action of the phosphate ester groups contained in the first additive and the second additive, the volume expansion of the electrode can be restrained, the expansion stress is prevented from damaging the interface of the surface of the electrode, the contact between the electrolyte and the electrode material is blocked, the oxidation resistance of the electrolyte is improved, the performance stability of the battery under high voltage is improved, and the high-temperature storage and circulation performance of the battery are improved.

Detailed Description

The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the invention may be practiced otherwise than as described herein. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

The electrolyte and the battery provided by the embodiment of the invention are described in detail below through specific embodiments and application scenes thereof.

The electrolyte of the embodiment of the invention comprises the following components:

electrolyte, solvent, first additive and second additive, the first additive is selected from at least one of structural formula (1) to structural formula (4),

wherein R is ₁ 、R ₂ And R is ₃ Each independently selected from C ₁ -C ₂₀ One of an alkane, a haloalkane, an aromatic hydrocarbon or a halogenated aromatic hydrocarbon;

the second additive is selected from at least one of structural formulas (5) to (7),

the electrolyte may include: at least one of lithium hexafluorophosphate, lithium difluorophosphate, lithium difluorooxalato borate, lithium bistrifluoromethylsulfonyl imide, lithium difluorobisoxalato phosphate, lithium tetrafluoroborate, lithium bisoxalato borate, lithium hexafluoroantimonate, lithium hexafluoroarsenate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium tris (trifluoromethylsulfonyl) methyl and lithium bis (trifluoromethylsulfonyl) imide, for example, the electrolyte may be lithium hexafluorophosphate, and the specific kind of electrolyte may be selected according to the actual use. The solvent may include at least one of a carbonate and a carboxylate. The solvent may be a nonaqueous organic solvent, and the solvent may include at least one of a halogen-substituted carbonate and a halogen-substituted carboxylate. The carbonate may include at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and methylethyl carbonate; the carboxylic acid ester may include at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl propionate, ethyl propionate, methyl butyrate and ethyl n-butyrate, and the specific kind of the solvent may be selected according to the actual use.

The electrolyte of the embodiment of the invention comprises the following components: the electrolyte, the solvent, the first additive and the second additive, wherein the first additive is selected from at least one of structural formulas (1) to (4), and the second additive is selected from at least one of structural formulas (5) to (7). The first additive is a phosphorus-containing compound with unsaturated bonds, has high oxidation resistance, can absorb single-wire oxygen released by the positive electrode under high voltage and inhibit oxidative decomposition of a solvent, and the unsaturated double bonds contained in the first additive can be polymerized at the negative electrode to form an SEI protective film, so that the formed protective film can inhibit volume expansion of a silicon negative electrode and further prevent electrolyte from entering the negative electrode material to cause damage. The second additive is a thiophene structure containing single or multiple phosphate esters, the thiophene structure can be polymerized on the surface of the positive electrode, a polymerized film can be formed on the surface of the positive electrode by the second additive under high voltage, the contact between electrolyte and a positive electrode material can be effectively blocked, meanwhile, the contained phosphate ester groups can improve the oxidation resistance of the electrolyte, a stable film layer can be formed on the surface of the electrode under the combined action of the phosphate ester groups contained in the first additive and the second additive, the volume expansion of the electrode can be restrained, the expansion stress is prevented from damaging the interface of the surface of the electrode, the contact between the electrolyte and the electrode material is blocked, the oxidation resistance of the electrolyte is improved, the performance stability of the battery under high voltage is improved, and the high-temperature storage and circulation performance of the battery are improved.

In some embodiments, R ₁ 、R ₂ And R is ₃ May each be independently selected from C substituted or unsubstituted with halogen ₁ -C ₂₀ C which is substituted or unsubstituted by halogen ₃ -C ₂₀ Cycloalkyl of (C), phenyl substituted or unsubstituted by halogen, biphenyl substituted or unsubstituted by halogen, C substituted or unsubstituted by halogen ₆ -C ₂₆ The carbon atom in the phenylalkyl, halogen-substituted or unsubstituted condensed ring aromatic hydrocarbon group may be 26 or less, R ₁ 、R ₂ And R is ₃ The specific number of carbon atoms can be reasonably selected according to practical conditions.

Alternatively, R ₁ 、R ₂ And R is ₃ Can each be independently selected from C substituted or unsubstituted by F ₁ -C ₅ C, substituted or unsubstituted by F ₃ -C ₅ Cycloalkyl, phenyl substituted or unsubstituted by F, C substituted or unsubstituted by F ₆ -C ₉ A phenylalkyl group of (C), a condensed ring aromatic hydrocarbon group substituted or unsubstituted with F. The carbon atom in the condensed ring aromatic hydrocarbon group substituted or unsubstituted with F may be 26 or less, R ₁ 、R ₂ And R is ₃ The specific number of carbon atoms can be reasonably selected according to practical conditions.

Alternatively, the first additive may be selected from at least one of the structural formulas 1 to 10,

for example, the first additive may be selected from formulas 1 to 1, formulas 1 to 6, formulas 1 to 9, or formulas 1 to 10, and the first additive may be simultaneously selected from a plurality of formulas 1 to 10.

In some embodiments, the first additive may be present in an amount of 0.1-5.0% of the total mass of the electrolyte. For example, the content of the first additive may be 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.2wt%, 1.3wt%, 1.5wt%, 1.6wt%, 1.8wt%, 2wt%, 2.2wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.8wt%, 3wt%, 3.3wt%, 3.5wt%, 3.8wt%, 4wt%, 4.2wt%, 4.5wt%, 4.8wt% or 5wt% of the total mass of the electrolyte, and the specific content of the first additive may be selected according to the actual use.

In other embodiments, the second additive may be present in an amount of 0.1 to 5.0% by weight of the total electrolyte. For example, the content of the second additive may be 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.2wt%, 1.3wt%, 1.5wt%, 1.6wt%, 1.8wt%, 2wt%, 2.2wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.8wt%, 3wt%, 3.3wt%, 3.5wt%, 3.8wt%, 4wt%, 4.2wt%, 4.5wt%, 4.8wt% or 5wt% of the total mass of the electrolyte, and the specific content of the second additive may be selected according to the actual use.

Alternatively, the electrolyte may include: lithium hexafluorophosphate (LiPF) ₆ ) Lithium difluorophosphate (LiPO) ₂ F ₂ ) At least one of lithium difluorooxalato borate (LiDFOB), lithium bistrifluoromethylsulfonyl imide, lithium difluorobisoxalato phosphate, lithium tetrafluoroborate, lithium bisoxalato borate, lithium hexafluoroantimonate, lithium hexafluoroarsenate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium tris (trifluoromethylsulfonyl) methyl lithium and lithium bis (trifluoromethylsulfonyl) imide. For example, the electrolyte may be lithium hexafluorophosphate, the electrolyte may include lithium hexafluorophosphate and lithium bistrifluoromethylsulfonyl imide, and the specific type of the electrolyte may be reasonably selected according to practice.

Optionally, the electrolyte may further include: at least one of fluoroethylene carbonate, 1, 3-propane sultone and 1,3, 6-hexane trinitrile. For example, the electrolyte may also include fluoroethylene carbonate or 1,3, 6-hexanetrinitrile. Other additives may be added to the electrolyte as needed.

Alternatively, the solvent may include: at least one of a carbonate and a carboxylate. The solvent may include at least one of a halogen-substituted carbonate and a halogen-substituted carboxylate. Wherein, the carbonic ester can include at least one of Ethylene Carbonate (EC), propylene Carbonate (PC), dimethyl carbonate, diethyl carbonate (DEC) and methyl ethyl carbonate, for example, the carbonic ester can include ethylene carbonate, and the carbonic ester can include ethylene carbonate and dimethyl carbonate, and can be specifically selected reasonably according to the needs. The carboxylic acid ester may include at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl Propionate (PP), ethyl Propionate (EP), methyl butyrate, and ethyl n-butyrate. For example, the carboxylic acid ester may include propyl acetate, and the carboxylic acid ester may include n-butyl acetate and ethyl propionate, and may be appropriately selected according to the needs.

The battery of the embodiment of the invention comprises:

the electrolyte described in the above examples. The battery with the electrolyte in the embodiment can form a stable film layer on the surface of the electrode through the combined action of the first additive and the second additive, can inhibit the volume expansion of the electrode, prevent the expansion stress from damaging the interface of the surface of the electrode, block the contact between the electrolyte and the electrode material, improve the antioxidation capability of the electrolyte, and be beneficial to improving the performance stability of the battery under high voltage and the high-temperature storage and circulation performance of the battery.

The battery can be a lithium ion battery, and the battery can also comprise a positive plate containing positive electrode active materials, a negative plate containing negative electrode active materials and a separation film. The positive electrode sheet may include a positive electrode current collector and a positive electrode active material layer coated on one or both side surfaces of the positive electrode current collector, and the positive electrode active material layer may include a positive electrode active material, a conductive agent, and a binder. The negative electrode sheet may include a negative electrode current collector and a negative electrode active material layer coated on one or both side surfaces of the negative electrode current collector, and the negative electrode active material layer may include a negative electrode active material, a conductive agent, and a binder. The positive electrode active material layer may include the following components in percentage by mass: 80-99.8wt% of positive electrode active material, 0.1-10wt% of conductive agent and 0.1-10wt% of binder. Preferably, the positive electrode active material layer may include, by mass: 90-99.6wt% of positive electrode active material, 0.2-5wt% of conductive agent and 0.2-5wt% of binder. The mass percentage of each component in the anode active material layer can be as follows: 80-99.8wt% of negative electrode active material, 0.1-10wt% of conductive agent, and 0.1-10wt% of binder. Preferably, the mass percentage of each component in the anode active material layer may be: 90-99.6wt% of negative electrode active material, 0.2-5wt% of conductive agent and 0.2-5wt% of binder.

The conductive agent may be at least one selected from conductive carbon black, acetylene black, ketjen black, conductive graphite, conductive carbon fiber, carbon nanotube, metal powder, and carbon fiber. The binder may be at least one selected from sodium carboxymethyl cellulose, styrene-butadiene latex, polytetrafluoroethylene, and polyethylene oxide. The negative electrode active material may be silicon-doped for artificial graphite. The positive electrode active material can be selected from one or more of transition metal lithium oxide, lithium iron phosphate and lithium manganate, and the chemical formula of the transition metal lithium oxide can be Li _{1+ x} Ni _y Co _z M _(1-y-z) O ₂ Wherein, -0.1 is less than or equal to x is less than or equal to 1,0 is less than or equal to y is less than or equal to 1,0 is less than or equal to z is less than or equal to 1, and 0 is less than or equal to y+z is less than or equal to 1; wherein M may be one or more of Mg, zn, ga, ba, al, fe, cr, sn, V, mn, sc, ti, nb, mo, zr.

The battery may include a negative electrode sheet, an electrolyte, a positive electrode sheet, a separator, and an outer package. The battery cell can be obtained by stacking the positive plate, the isolating film and the negative plate, or by winding the positive plate, the isolating film and the negative plate after stacking, the battery cell is placed in an outer package, and the electrolyte is injected into the outer package, so that the lithium ion battery can be obtained.

The invention will be further illustrated with reference to specific examples.

Example 1

Preparation of a positive plate:

lithium cobalt oxide (LiCoO) as a positive electrode active material ₂ ) Mixing polyvinylidene fluoride (PVDF), conductive carbon black (SP, super P) and Carbon Nano Tube (CNT) according to the mass ratio of 96:2:1.5:0.5, adding N-methyl pyrrolidone (NMP), and stirring under the action of a vacuum stirrer until the mixed system becomes anode active slurry with uniform fluidity; uniformly coating anode active slurry on two surfaces of an aluminum foil; and drying the coated aluminum foil, and then rolling and slitting to obtain the required positive plate.

Preparing a negative plate:

mixing negative electrode active materials of artificial graphite, silicon oxide, sodium carboxymethylcellulose (CMC-Na), styrene-butadiene rubber, conductive carbon black (SP) and single-walled carbon nanotubes (SWCNTs) according to the mass ratio of 79.5:15:2.5:1.5:1:0.5, adding deionized water, and obtaining negative electrode active slurry under the action of a vacuum stirrer; uniformly coating the anode active slurry on two surfaces of a copper foil; and (3) airing the coated copper foil at room temperature, transferring to an 80 ℃ oven for drying for 10 hours, and then carrying out cold pressing and slitting to obtain the negative plate.

Preparation of electrolyte:

and adding the electrolyte, the first additive and the second additive into the solvent, and uniformly mixing to obtain the electrolyte.

Solvent: EC 7 parts by weight, PC 7 parts by weight, DEC 14 parts by weight, PP 41 parts by weight, FEC (fluoroethylene carbonate) 10 parts by weight;

an electrolyte: lithium hexafluorophosphate (LiPF) ₆ ) 13 parts by weight;

other additives: 5 parts by weight of PS (1, 3-propane sultone) and 2.5 parts by weight of HTCN (1, 3, 6-hexanetrinitrile).

The specific contents of the components can be seen in Table 1.

Preparation of lithium ion batteries

Laminating the positive plate, the negative plate and the isolating film according to the sequence of the positive plate, the isolating film and the negative plate, and then winding to obtain an electric core; and placing the battery core in an outer packaging aluminum foil, injecting the prepared electrolyte into the outer packaging, and performing the procedures of vacuum packaging, standing, formation, shaping, sorting and the like to obtain the lithium ion battery. The charge and discharge range of the battery is 3.0-4.5V.

The comparative examples 1 to 9, examples 2 to 13 and example 1 are different in the components and contents of the electrolytic solution, and the components and contents of the comparative examples 1 to 9 and examples 2 to 13 can be shown in Table 1.

TABLE 1 Components and contents of electrolytes in comparative examples and examples

Test of cell Performance

1) 45 ℃ high temperature cycle performance test

The batteries in the comparative example and the example were subjected to charge-discharge cycle at 45 ℃ in a charge-discharge cut-off voltage range at a rate of 1C for 800 weeks, the discharge capacity at the 1 st week was measured as x1 mAh, and the discharge capacity at the nth week was measured as y1 mAh; the capacity at week N divided by the capacity at week 1 gives the cyclic capacity retention rate at week N r1=y1/x 1.

2) Safety performance test:

charging the battery cell 0.5C to the upper limit, cutting off the voltage, and keeping the voltage constant to 0.05C; placing the fully charged sample in a thermal shock test box at the ambient temperature of 25+/-5 ℃, then raising the temperature to 140+/-2 ℃ at the speed of 15+/-2 ℃/min, and keeping the temperature for 42min, and then finishing the test to observe whether the battery fires and explodes or not, if not, the battery does not fire or explode, wherein the safety performance is expressed as passing; if only fires, the fire is shown as "fire" if only explosions are generated, the fire is shown as "no pass" if both fires and explosions are generated, and the safety performance is shown as "no pass". The results of the performance test of the lithium ion batteries of the comparative examples and examples can be seen in table 2.

Table 2 results of performance tests of lithium ion batteries of comparative examples and examples

From the test results in table 2, the battery with the electrolyte of the embodiment of the invention can inhibit the volume expansion of the electrode, can improve the performance stability of the battery under high voltage, and can improve the high-temperature storage and cycle performance of the battery with high safety.

While the present invention has been described with reference to the above-described embodiments, it is to be understood that the same is not limited to the above-described embodiments, but rather that the same is intended to be illustrative only, and that many modifications may be made by one of ordinary skill in the art without departing from the spirit of the invention and scope of the appended claims.

Claims (10)

1. An electrolyte, comprising:

electrolyte, solvent, first additive and second additive, the first additive is selected from at least one of structural formula (1) to structural formula (4),

wherein R is ₁ 、R ₂ And R is ₃ Each independently selected from C ₁ -C ₂₀ One of an alkane, a haloalkane, an aromatic hydrocarbon or a halogenated aromatic hydrocarbon;

the second additive is selected from at least one of structural formulas (5) to (7),

2. the electrolyte according to claim 1, wherein R ₁ 、R ₂ And R is ₃ Each independently selected from C substituted or unsubstituted with halogen ₁ -C ₂₀ C which is substituted or unsubstituted by halogen ₃ -C ₂₀ Cycloalkyl of (C), phenyl substituted or unsubstituted by halogen, biphenyl substituted or unsubstituted by halogen, C substituted or unsubstituted by halogen ₆ -C ₂₆ A phenylalkyl group, a fused ring aromatic hydrocarbon group substituted or unsubstituted with halogen.

3. The electrolyte according to claim 2, wherein R ₁ 、R ₂ And R is ₃ Each independently selected from C substituted or unsubstituted with F ₁ -C ₅ C, substituted or unsubstituted by F ₃ -C ₅ Cycloalkyl, phenyl substituted or unsubstituted by F, C substituted or unsubstituted by F ₆ -C ₉ A phenylalkyl group of (C), a condensed ring aromatic hydrocarbon group substituted or unsubstituted with F.

4. The electrolyte of claim 1, wherein the first additive is selected from at least one of structural formulas 1-1 to 1-10,

5. the electrolyte according to any one of claims 1 to 4, wherein the content of the first additive is 0.1 to 5.0% of the total mass of the electrolyte.

6. The electrolyte according to any one of claims 1 to 4, wherein the content of the second additive is 0.1 to 5.0% of the total mass of the electrolyte.

7. The electrolyte of claim 1, wherein the electrolyte comprises:

at least one of lithium hexafluorophosphate, lithium difluorophosphate, lithium difluorooxalato borate, lithium bistrifluoromethylsulfonyl imide, lithium difluorobisoxalato phosphate, lithium tetrafluoroborate, lithium bisoxalato borate, lithium hexafluoroantimonate, lithium hexafluoroarsenate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium tris (trifluoromethylsulfonyl) methyl imide, and lithium bis (trifluoromethylsulfonyl) imide; and/or

The electrolyte further comprises: at least one of fluoroethylene carbonate, 1, 3-propane sultone and 1,3, 6-hexane trinitrile.

8. The electrolyte of claim 1, wherein the solvent comprises: at least one of a carbonate and a carboxylate.

9. The electrolyte of claim 8, wherein the carbonate comprises at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethylmethyl carbonate;

the carboxylic acid ester comprises at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl propionate, ethyl propionate, methyl butyrate and ethyl n-butyrate.

10. A battery, comprising:

the electrolyte of any one of claims 1-9.