Electrolyte, lithium ion battery and electric equipment

Abstract

The invention provides an electrolyte, a lithium ion battery and electric equipment, the electrolyte comprises an additive, the additive comprises a compound shown in a formula I: # imgabs0 #, by adopting the additive, the self-extinguishing time of the electrolyte can be shortened, the safety performance of the battery is improved, and the electrochemical performance of the battery is not influenced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to electrolytes, lithium-ion batteries and electrical equipment. Background Art

[0002] In recent years, environmental pollution and the depletion of fossil energy have become increasingly serious. Human beings have an increasingly urgent need for new energy, and the development of new energy is inseparable from energy storage devices. At present, the most widely used energy storage device is the lithium-ion battery. Due to its advantages such as high energy density, long cycle life, high power density, and low environmental pollution, it is not only widely used in portable electronic devices, but also gradually becomes the main power source for electric vehicles. However, in recent years, there have been frequent reports of fires and even explosions caused by power batteries, and the safety of lithium-ion batteries has attracted widespread attention. The main cause of such accidents is thermal runaway caused by exothermic reactions under abuse conditions. Improving the safety of the electrolyte is an important means to improve battery safety.

[0003] The current high-safety electrolyte is mainly achieved through optimizing the selection of electrolyte main salt, design and optimization of functional electrolyte additives and other technologies. The principle of the current related technical solutions is to block the subsequent reactions after the battery generates heat and shorten the electrolyte combustion time, but it cannot reduce the heat generation of the battery and reduce the probability of thermal runaway of the battery, and the improvement of battery safety is limited. In addition, the use of flame retardant additives, in order to achieve the flame retardant effect, often the amount of its addition is large, which will significantly increase the impedance and seriously affect the battery performance.

[0004] Therefore, the technology related to high-safety electrolyte still needs to be improved. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the present application proposes an electrolyte, a lithium-ion battery and an electrical device with excellent safety.

[0006] In a first aspect of the present application, an electrolyte is provided. According to an embodiment of the present application, the electrolyte includes an additive, and the additive includes a compound shown in formula I:

[0007]

[0008] Wherein, R1 is selected from any one of H, F, alkyl, fluoroalkyl, alkoxy and fluoroalkoxy;

[0009] Each L1 is independently selected from any one of -O-R2, -B-R3, and -N-R4R5;

[0010] R2, R3, R4, and R5 are each independently selected from any one of optionally substituted alkyl, optionally substituted haloalkyl, optionally substituted alkoxy, optionally substituted haloalkoxy and optionally substituted phenyl; the substituents on the above groups are each independently selected from at least one of alkyl, haloalkyl, alkoxy, haloalkoxy, phenyl, oxygen-containing heterocycle, nitrogen-containing heterocycle and sulfur-containing heterocycle; the halogen in the haloalkyl and haloalkoxy groups is each independently selected from at least one of F, Cl and Br.

[0011] By adopting the above-mentioned additives, the self-extinguishing time of the electrolyte can be reduced, the thermal stability of the electrolyte can be improved, the battery safety performance can be improved, and there is basically no negative impact on the electrochemical performance of the battery. Specifically, the non-flammable additive obtained by using a phosphazene monomer containing an unsaturated double bond in the above-mentioned additive greatly reduces the safety risk of causing a fire. In summary, the above-mentioned electrolyte of the present application can efficiently conduct lithium ions, can generate a uniform and dense SEI film with high ion conductivity on the negative electrode, has a wide electrochemical window, and has excellent safety performance.

[0012] According to the embodiments of the present application, R1 is selected from H, F, C 1～6 Alkyl, C 1～6 Fluorinated alkyl, C 1～6 Alkoxy and C 1～6 Fluorinated alkoxy; R2, R3, R4, R5 are each independently selected from optionally substituted C 1～6 Alkyl, optionally substituted C 1～6 haloalkyl, optionally substituted C 1～6 Alkoxy, optionally substituted C 1～6 One of haloalkoxy and optionally substituted phenyl, the substituents on the above groups are each independently selected from C 1～6 Alkyl, C 1～6 Haloalkyl, C 1～6 Alkoxy, C 1～6 At least one of a halogenated alkoxy group, a phenyl group, an oxygen-containing heterocycle, a nitrogen-containing heterocycle, and a sulfur-containing heterocycle.

[0013] According to an embodiment of the present application, R1 is selected from C 1～6 Alkyl; each L1 is independently selected from any one of -O-R2, -N-R4R5; R2, R4, R5 are independently selected from C 1～6 Alkyl, C 1～6 Any of the halogenated alkyl groups.

[0014] According to an embodiment of the present application, the additive may include at least one of the following compounds:

[0015]

[0016] Specifically, the use of the above-mentioned specific compounds can better reduce the self-extinguishing time of the electrolyte, improve the electrochemical performance of the battery, and inhibit the high-temperature gas production of the battery. At the same time, the above-mentioned compounds are easily available.

[0017] According to an embodiment of the present application, in the electrolyte, the mass percentage of the additive is 1% to 10%, specifically 0.2% to 2%. Within the above content range, the flammability of the electrolyte can be effectively reduced, the self-extinguishing time of the electrolyte can be reduced, and at the same time, the battery impedance will not be increased due to a large amount of addition, which will seriously affect the battery performance.

[0018] According to an embodiment of the present application, the electrolyte further includes an organic solvent, the organic solvent includes ethylene carbonate, and in the electrolyte, the mass percentage of the ethylene carbonate is 10% to 22%, preferably 14% to 18%. By optimizing the type and proportion of the organic solvent, the heat generation of the battery can be effectively reduced, and the probability of thermal runaway of the battery can be reduced. When used in conjunction with the above-mentioned additives, the probability of thermal runaway can be reduced while reducing flammability, and the self-extinguishing time of the electrolyte can be further reduced. At the same time, the battery performance will not be substantially affected. The electrolyte is suitable for high-energy density, high-safety mixed chemical system battery electrolyte, and can effectively improve the safety issues such as side reaction heat generation of the electrolyte and battery cell explosion when the battery has thermal runaway.

[0019] According to an embodiment of the present application, the organic solvent further comprises at least one of propylene carbonate, dimethyl carbonate, fluoroethylene carbonate, diethyl carbonate, ethyl methyl carbonate, dimethyl carbonate, and fluorodiethyl carbonate. The above solvents have a better solvation effect, which is beneficial to optimize battery performance, and have better lithium ion transmission performance, so that the lithium ion battery using the electrolyte has better electrochemical performance.

[0020] According to an embodiment of the present application, in the electrolyte, the mass percentage of the organic solvent is 60% to 85%.

[0021] According to an embodiment of the present application, the electrolyte further includes an electrolyte salt, and the electrolyte salt includes at least one of lithium bis(trifluoromethylsulfonyl)imide, lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium difluorooxalate borate, lithium bis(oxalate borate), lithium difluorophosphate, lithium difluorobis(oxalate phosphate), and lithium tetrafluoroborate. Thus, it is possible to provide better ion transport performance, suitable conductivity, stability, and compatibility with electrode materials, and thus the lithium ion battery using the electrolyte has better electrochemical performance.

[0022] According to an embodiment of the present application, in the electrolyte, the mass percentage of the electrolyte salt is 10% to 20%. Therefore, the electrolyte has better ion transport performance, conductivity, stability and compatibility with electrode materials.

[0023] In a second aspect of the present application, a lithium-ion battery is provided. According to an embodiment of the present application, the lithium-ion battery comprises the electrolyte described above. The lithium-ion battery has low heat generation and low risk of thermal runaway. At the same time, the electrolyte has poor flammability, short self-extinguishing time, and excellent thermal stability and safety.

[0024] In a third aspect of the present application, an electric device is provided. According to an embodiment of the present application, the electric device includes the lithium-ion battery described above. The electric device has all the features and advantages of the lithium-ion battery described above, which will not be described one by one here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the electrolyte self-extinguishing time testing device of the present application. DETAILED DESCRIPTION

[0026] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0027] In a first aspect of the present application, an electrolyte is provided. According to an embodiment of the present application, the electrolyte includes an additive, and the additive includes a compound shown in formula I:

[0028]

[0029] Wherein, R1 is selected from any one of H, F, alkyl, fluoroalkyl, alkoxy and fluoroalkoxy;

[0030] Each L1 is independently selected from any one of -O-R2, -B-R3, and -N-R4R5;

[0031] R2, R3, R4, and R5 are each independently selected from any one of optionally substituted alkyl, optionally substituted haloalkyl, optionally substituted alkoxy, optionally substituted haloalkoxy and optionally substituted phenyl; the substituents on the above groups are each independently selected from at least one of alkyl, haloalkyl, alkoxy, haloalkoxy, phenyl, oxygen-containing heterocycle, nitrogen-containing heterocycle and sulfur-containing heterocycle; the halogen in the haloalkyl and haloalkoxy groups is each independently selected from at least one of F, Cl and Br.

[0032] By adopting the above-mentioned additives, not only can the self-extinguishing time of the electrolyte be reduced, but also the electrochemical performance of the battery can be improved, while reducing the cost of the battery; at the same time, the above-mentioned additives also have the effect of inhibiting the high-temperature gas production of the battery, further improving the safety performance of the battery. Specifically, the non-flammable additive obtained by using a phosphazene monomer containing an unsaturated double bond in the above-mentioned additive greatly reduces the safety risk of causing a fire. In summary, the above-mentioned electrolyte of the present application can efficiently conduct lithium ions, can generate a uniform and dense SEI film with high ion conductivity on the negative electrode, has a wide electrochemical window, and has excellent safety performance.

[0033] According to the embodiments of the present application, R1 is selected from H, F, C 1～6 Alkyl, C 1～6 Fluorinated alkyl, C 1～6 Alkoxy and C 1～6 Fluoroalkoxy;

[0034] R2, R3, R4, and R5 are each independently selected from optionally substituted C 1～6 Alkyl, optionally substituted C 1～6 haloalkyl, optionally substituted C 1～6 Alkoxy, optionally substituted C 1～6 One of haloalkoxy and optionally substituted phenyl, the substituents on the above groups are each independently selected from C 1～6 Alkyl, C 1～6 Haloalkyl, C 1～6 Alkoxy, C 1～6 At least one of a halogenated alkoxy group, a phenyl group, an oxygen-containing heterocycle, a nitrogen-containing heterocycle, and a sulfur-containing heterocycle.

[0035] According to an embodiment of the present application, R1 is selected from C 1～6 Alkyl; each L1 is independently selected from any one of -O-R2, -N-R4R5; R2, R4, R5 are independently selected from C 1～6 Alkyl, C 1～6 Any of the halogenated alkyl groups.

[0036] According to an embodiment of the present application, the additive may include at least one of the following compounds:

[0037]

[0038] Specifically, the use of the above-mentioned specific compounds can better reduce the self-extinguishing time of the electrolyte, improve the electrochemical performance of the battery, and inhibit the high-temperature gas production of the battery. At the same time, the above-mentioned compounds are easy to obtain and have low cost.

[0039] According to an embodiment of the present application, in the electrolyte, the mass percentage of the additive is 1% to 10%, specifically 0.2% to 2%, such as 1%, 1.5%, 2%, .5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, etc. Within the above content range, the flammability of the electrolyte can be effectively reduced, the self-extinguishing time of the electrolyte can be reduced, and at the same time, the battery impedance will not be increased due to a large amount of addition, which will seriously affect the battery performance.

[0040] According to an embodiment of the present application, the electrolyte further includes an organic solvent, the organic solvent includes ethylene carbonate, and in the electrolyte, the mass percentage of the ethylene carbonate is 10% to 22%, preferably 14% to 18%. For example, it can be 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, etc. By optimizing the type and proportion of organic solvents, the heat generation of the battery can be effectively reduced, and the probability of thermal runaway of the battery can be reduced. When used in combination with the above-mentioned additives, the flammability can be reduced while reducing the probability of thermal runaway, and the self-extinguishing time of the electrolyte can be further reduced. At the same time, the battery performance will not be basically affected. The electrolyte is suitable for the electrolyte of a high-energy-density, high-safety mixed chemical system battery, and can effectively improve the safety problems such as the side reaction heat generation of the electrolyte and the explosion of the battery cell when the battery has thermal runaway.

[0041] According to an embodiment of the present application, the organic solvent further comprises at least one of propylene carbonate, dimethyl carbonate, fluoroethylene carbonate, diethyl carbonate, ethyl methyl carbonate, dimethyl carbonate, and fluorodiethyl carbonate. The above solvents have a better solvation effect, which is beneficial to optimize battery performance, and have better lithium ion transmission performance, so that the lithium ion battery using the electrolyte has better electrochemical performance.

[0042] According to an embodiment of the present application, in the electrolyte, the mass percentage of the organic solvent is 60% to 85%, specifically 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85% and the like.

[0043] According to an embodiment of the present application, the electrolyte further includes an electrolyte salt, and the electrolyte salt includes at least one of lithium bis(trifluoromethylsulfonyl)imide, lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium difluorooxalate borate, lithium bis(oxalate borate), lithium difluorophosphate, lithium difluorobis(oxalate phosphate), and lithium tetrafluoroborate. Thus, it is possible to provide better ion transport performance, suitable conductivity, stability, and compatibility with electrode materials, and thus the lithium ion battery using the electrolyte has better electrochemical performance.

[0044] According to an embodiment of the present application, in the electrolyte, the mass percentage of the electrolyte salt is 10% to 20%, specifically 10%, 11%, 2%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, etc. As a result, the electrolyte has better ion transport performance, conductivity, stability and compatibility with electrode materials.

[0045] In a second aspect of the present application, a lithium-ion battery is provided. According to an embodiment of the present application, the lithium-ion battery comprises the electrolyte described above. The lithium-ion battery has low heat generation and low risk of thermal runaway. At the same time, the electrolyte has poor flammability, short self-extinguishing time, and excellent thermal stability and safety.

[0046] It can be understood that in addition to the electrolyte mentioned above, the lithium-ion battery can also include an electrode assembly and an outer packaging, the electrode assembly and the electrolyte are contained in the outer packaging, and the electrode assembly can include a positive electrode sheet, a negative electrode sheet and a separation membrane arranged between the positive electrode sheet and the negative electrode sheet, specifically, it can be a stacked electrode assembly or a wound electrode assembly.

[0047] The positive electrode sheet may include a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, wherein the positive electrode film layer includes a positive electrode active material, a conductive agent, and a binder.

[0048] The positive electrode active material includes but is not limited to lithium transition metal oxides and / or lithium phosphates with olivine structure. Specifically, the lithium transition metal oxides include lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as NCM333, NCM523, NCM211, NCM622, NCM811), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) or a combination thereof; olivine-structured lithium-containing phosphates include but are not limited to lithium iron phosphate (such as LiFePO4), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate (such as LiMnx Fe 1-x PO4, 0<x<1), at least one of a composite material of lithium manganese iron phosphate and carbon.

[0049] The positive electrode conductive agent may include one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers, which is not limited in the embodiments of the present application.

[0050] The positive electrode binder may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyacrylic acid (PAA), polyvinyl alcohol (PVA), ethylene-vinyl acetate copolymer (EVA), styrene-butadiene rubber (SBR), carboxymethyl cellulose (CMC), sodium alginate (SA), polymethacrylic acid (PMA) and carboxymethyl chitosan (CMCS).

[0051] The positive electrode current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. The composite current collector may include a polymer material base and a metal layer formed on at least one surface of the polymer material base. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0052] In some embodiments, the negative electrode plate includes a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, and the negative electrode film layer includes a negative electrode active material.

[0053] The negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, a copper foil may be used. The composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector may be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0054] The negative electrode active material may include one or more of a carbon-based material, a silicon-based material, a tin-based material, and lithium titanate. The carbon-based material may include one or more of graphite (e.g., artificial graphite, natural graphite, etc.), soft carbon, and hard carbon. The silicon-based material may include one or more of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may include one or more of elemental tin, tin oxide compounds, and tin alloys.

[0055] The negative electrode film layer may include a negative electrode binder. As an example, the negative electrode binder may include one or more of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA) and carboxymethyl chitosan (CMCS), and the present application embodiment is not limited to this.

[0056] The negative electrode film layer may further include a negative electrode conductive agent. As an example, the negative electrode conductive agent may include one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers, which is not limited in the present application.

[0057] It can be understood that there is no special restriction on the specific type of the battery, which can be a primary battery or a secondary battery; the shape of the battery can be a cylindrical battery, a square battery or a battery of any other shape, etc., and according to the outer packaging classification, the battery can be a hard shell battery, a soft pack battery, etc.

[0058] In a third aspect of the present application, an electric device is provided. According to an embodiment of the present application, the electric device includes the lithium-ion battery described above. The electric device has all the features and advantages of the lithium-ion battery described above, which will not be described one by one here.

[0059] According to the embodiments of the present application, there is no particular limitation on the specific types of electrical equipment. As examples, electrical equipment may include mobile devices (such as mobile phones, laptop computers, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but are not limited thereto.

[0060] The embodiments of the present application are described in detail below.

[0061] Example 1

[0062] Preparation of electrolyte: Weigh EC according to 12% of the total electrolyte mass, and make up the rest of the solvent by mass from DEC and EMC, and mix them evenly to obtain an organic solvent. Weigh LiPF6 required for preparing an electrolyte with a lithium salt concentration of about 1M, slowly add LiPF6 to the organic solvent, fully dissolve it, then add 5wt% of compound 1, continue stirring until dissolved, and prepare a lithium-ion battery electrolyte. The mass ratio of the electrolyte formula is shown in Table 1.

[0063] Preparation of soft pack battery: The negative electrode surface density of graphite negative electrode material is 180g m -2 , compacted density is 1.56gm -3 ; The positive electrode material is lithium iron phosphate, and the positive electrode surface density is 390g m-2 The positive electrode sheet, the separator, and the negative electrode sheet are stacked in order, the separator is placed between the positive and negative electrode sheets, and the bare battery cell is wound; the bare battery cell is placed in an aluminum-plastic film package, the electrolyte prepared above is injected into the dried battery, and the battery is allowed to stand at room temperature to complete the preparation of the lithium-ion soft-pack battery.

[0064] Embodiments 2 to 11

[0065] Same as Example 1, specific differences are shown in Table 1.

[0066] Comparative Examples 1 to 3

[0067] Same as Example 1, specific differences are shown in Table 1.

[0068] Table 1

[0069]

[0070]

[0071] Performance testing:

[0072] 1. Battery cycle performance test: The formed battery is charged to 3.8V at a constant current and constant voltage of 0.5C current. The cut-off current of constant voltage charging is 0.05C. It is left to stand for 10 minutes, and then discharged to 2.0V at a constant current of 0.5C current. The cycle is repeated for 500 times. The capacity retention rate test results are shown in Table 2.

[0073] 2. Self-extinguishing time test: The electrolytes in the embodiments and comparative examples were Figure 1 The electrolyte self-extinguishing device shown in the figure uses a spherical core with a diameter of 0.3-0.5 cm to absorb 0.05-0.10 g of electrolyte and records the time s from the unit weight of electrolyte from combustion to extinguishment. That is, the recording unit of self-extinguishing time is s·g -1 .

[0074] Table 2

[0075]

[0076] According to the data in Table 2, after using the additives of the present application, the battery performance remains the same, and the performance difference between each group is very small, indicating that the electrolyte in the present application does not have a significant impact on the cycle performance of the battery.

[0077] It can also be seen from Table 2 that the self-extinguishing time is significantly reduced when the EC content is reduced from 22% (Comparative Example 2) to 12% (Comparative Example 1), and is further reduced after adding the flame retardant additive (Example 1). Compared with Comparative Example 2, the self-extinguishing time is reduced by adding 5% TTFP, but it is still lower than the example, which proves that the compound 1 additive in Example 1 is more effective in reducing the self-extinguishing time compared with TTFP.

[0078] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0079] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An electrolyte, characterized in that: Including additives, the additives include compounds shown in formula I: Wherein, R1 is selected from any one of H, F, alkyl, fluoroalkyl, alkoxy and fluoroalkoxy; Each L1 is independently selected from any one of -O-R2, -B-R3, and -N-R4R5; R2, R3, R4, and R5 are each independently selected from any one of optionally substituted alkyl, optionally substituted haloalkyl, optionally substituted alkoxy, optionally substituted haloalkoxy and optionally substituted phenyl; the substituents on the above R2, R3, R4, and R5 are each independently selected from at least one of alkyl, haloalkyl, alkoxy, haloalkoxy, phenyl, oxygen-containing heterocycle, nitrogen-containing heterocycle and sulfur-containing heterocycle; the halogen in the haloalkyl and haloalkoxy groups are each independently selected from at least one of F, Cl and Br.

2. The electrolyte according to claim 1, characterized in that R1 is selected from H, F, C 1～6 Alkyl, C 1～6 Fluorinated alkyl, C 1～6 Alkoxy and C 1～6 Fluoroalkoxy; R2, R3, R4, and R5 are each independently selected from optionally substituted C 1～6 Alkyl, optionally substituted C 1～6 haloalkyl, optionally substituted C 1～6 Alkoxy, optionally substituted C 1～6 One of haloalkoxy and optionally substituted phenyl, wherein the substituents on R2, R3, R4, and R5 are independently selected from C 1～6 Alkyl, C 1～6 Haloalkyl, C 1～6 Alkoxy, C 1～6 At least one of a halogenated alkoxy group, a phenyl group, an oxygen-containing heterocycle, a nitrogen-containing heterocycle, and a sulfur-containing heterocycle.

3. The electrolyte according to claim 1, characterized in that R1 is selected from C 1～6 alkyl; Each L1 is independently selected from any one of -O-R2, -N-R4R5; R2, R4, R5 are each independently selected from C 1～6 Alkyl, C 1～6 Any of the halogenated alkyl groups.

4. The electrolyte according to claim 1, characterized in that The additive comprises at least one of the following compounds:

5. The electrolyte according to claim 1, characterized in that Based on the total mass of the electrolyte, the mass percentage of the additive is 1% to 10%, preferably 0.2% to 2%.

6. The electrolyte according to claim 1, characterized in that The electrolyte further comprises an organic solvent, wherein the organic solvent comprises ethylene carbonate, and based on the total mass of the electrolyte, the mass percentage of the ethylene carbonate is 10% to 22%, preferably 14% to 18%.

7. The electrolyte according to claim 6, characterized in that The organic solvent further comprises at least one of propylene carbonate, dimethyl carbonate, fluoroethylene carbonate, diethyl carbonate, ethyl methyl carbonate, dimethyl carbonate, and fluorodiethyl carbonate.

8. The electrolyte according to claim 7, characterized in that Based on the total mass of the electrolyte, the mass percentage of the organic solvent is 60% to 85%.

9. The electrolyte according to claim 1, characterized in that The electrolyte salt includes at least one of lithium bis(trifluoromethylsulfonyl)imide, lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium difluorooxalatoborate, lithium bis(oxalatoborate), lithium difluorophosphate, lithium difluorobis(oxalatophosphate), and lithium tetrafluoroborate.

10. The electrolyte according to claim 9, characterized in that Based on the total mass of the electrolyte, the mass percentage of the electrolyte salt is 10% to 20%.

11. A lithium ion battery, characterized in that: The electrolyte comprising the electrolyte according to any one of claims 1 to 10.

12. An electrical equipment, characterized in that: Includes the lithium ion battery as claimed in claim 11.

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