Non-aqueous electrolyte and lithium ion battery thereof

Abstract

The invention provides a non-aqueous electrolyte and a lithium ion battery thereof. The non-aqueous electrolyte comprises a lithium salt, an organic solvent and an additive, and the additive comprises an oxazolone compound as shown in a formula IV and at least one cyclic sulfonic anhydride compound as shown in a formula I, a formula II and a formula III, r1-R7 are each independently selected from a hydrogen atom, a halogen atom, a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkynyl group, r8-R10 are respectively and independently selected from hydrogen atoms, amino groups, substituted or unsubstituted C1-C10 alkyl groups, substituted or unsubstituted C2-C10 alkenyl groups, substituted or unsubstituted C2-C10 alkynyl groups and X groups, the structure of the X groups is shown as a formula 5, and * represents a connecting end. According to the non-aqueous electrolyte disclosed by the invention, the cyclic sulfonic anhydride compound and the oxazolone compound are added as additives, so that the high-temperature cycle performance and the high-temperature storage performance of the lithium ion battery can be effectively improved. # imgabs0 #, # imgabs1 # # imgabs2 #.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium ion batteries, and in particular relates to a non-aqueous electrolyte and a lithium ion battery thereof. Background Art

[0002] Lithium-ion batteries (LIB) have been widely used in electronic products, electric aircraft and electric vehicles due to their high energy density, long cycle life and high operating voltage. Among the existing positive electrode materials, ternary materials such as LiNi x Co y Mn 1-x-y O2 (NCM) boasts a high specific capacity, operating voltage platform, and excellent rate performance, making it a key player in the electric vehicle sector. Furthermore, by increasing the battery's charge cutoff voltage, the ternary material can release more lithium ions at higher voltages, thereby increasing the battery's energy density.

[0003] However, high-voltage ternary lithium-ion batteries also face some challenges in practical applications. First, the electrochemical stability window of existing carbonate-based electrolytes is relatively narrow. When the battery voltage reaches about 4.5V, the electrolyte will undergo severe oxidative decomposition, resulting in a decrease in battery performance. Therefore, the development of new high-voltage electrolyte systems or high-voltage film-forming additives is the key to improving battery performance. In addition, under high voltage conditions, the side reactions between the positive electrode material and the electrolyte will intensify, resulting in reduced cycle stability and safety of the battery. Therefore, higher requirements are also placed on the cycle performance, storage performance, etc. of high-voltage batteries. Therefore, it is urgent to develop an electrolyte suitable for power-type high-voltage batteries to address the shortcomings of the existing technology. Summary of the Invention

[0004] In view of the above problems, the object of the present invention is to provide a non-aqueous electrolyte and a lithium-ion battery thereof, in which cyclic sulfonic anhydride compounds and oxazolone compounds are introduced as additives to the non-aqueous electrolyte, which can effectively improve the high-temperature cycle performance and high-temperature storage performance of the lithium-ion battery.

[0005] To achieve the above object, the present invention provides a non-aqueous electrolyte comprising a lithium salt, an organic solvent, and an additive, wherein the additive comprises an oxazolone compound represented by Formula 4 and at least one cyclic sulfonic anhydride compound selected from Formulas 1, 2, and 3.

[0006]

[0007] wherein R1 to R7 are each independently selected from a hydrogen atom, a halogen atom, a substituted or unsubstituted C1 to C 10 Alkyl, substituted or unsubstituted C2 to C 10Alkenyl, substituted or unsubstituted C2 to C 10 Alkynyl, R8~R 10 are independently selected from hydrogen atoms, amino groups, X groups, substituted or unsubstituted C1 to C 10 Alkyl, substituted or unsubstituted C2 to C 10 Alkenyl, substituted or unsubstituted C2 to C 10 Alkynyl, the structure of the X group is shown in Formula 5, * represents the connecting end, .

[0008] Compared with the prior art, the non-aqueous electrolyte of the present invention uses cyclic sulfonic anhydride compounds and oxazolone compounds as additives, wherein the cyclic sulfonic anhydride compound is an unsaturated cyclic compound with a reduction potential of ~1.5V (vs. Li / Li + ), which can preferentially undergo reduction and decomposition on the negative electrode surface to form a stable SEI film, which can effectively reduce the side reactions between the electrolyte and the negative electrode material and improve the structural stability of the negative electrode material. However, the steric hindrance of its cyclic rigid structure is large, the viscosity of the electrolyte increases, and the reaction rate is reduced, thereby increasing the battery impedance, which has a deteriorating effect on the high-temperature storage and high-temperature cycle performance of the battery. Therefore, the present invention further introduces oxazolone compounds into the non-aqueous electrolyte, which has a reduction potential of about 1.0V and can preferentially undergo a reduction reaction in the solvent on the negative electrode surface to form a SEI film rich in Li3N / Li2O, synergistically regulate the components of the solid electrolyte membrane, reduce the interfacial impedance, and reduce the decomposition and gas production of the electrolyte at high temperature, thereby improving the high-temperature storage performance of the battery. At the same time, the polar structures (such as carbonyl groups and nitrogen heterocycles) contained in the oxazolone compounds can enhance the dissociation of lithium salts (such as LiPF6) and improve Li + The concentration of cyclic sulfonic acid anhydride compounds and oxazolone compounds can effectively improve the storage and cycling performance of lithium-ion batteries at high temperatures.

[0009] Correspondingly, the present invention also provides a lithium-ion battery, which includes a positive electrode material, a negative electrode material and the aforementioned non-aqueous electrolyte. Since the lithium-ion battery contains the non-aqueous electrolyte, it has good high-temperature storage performance and high-temperature cycle performance. DETAILED DESCRIPTION

[0010] The lithium-ion battery of the present invention comprises a positive electrode material, a negative electrode material and a non-aqueous electrolyte. The positive electrode material of the present invention is selected from at least one of nickel-cobalt-manganese oxide and nickel-cobalt-aluminum oxide. Specifically, the chemical formula of nickel-cobalt-manganese oxide is LiNi x Co y Mn z M(1-x-y-z) O2, and the chemical formula of nickel cobalt aluminum oxide is LiNi x Co y Al z N (1-x-y-z) O2, where M is at least one of Mg, Cu, Zn, Al, Sn, B, Ga, Cr, Sr, V, and Ti, N is at least one of Mn, Mg, Cu, Zn, Sn, B, Ga, Cr, Sr, V, and Ti, 0 < x < 1, 0 < y < 1, 0 < z < 1, and x + y + z ≤ 1. As an example, the cathode material is lithium nickel cobalt manganate, and its chemical formula is LiNi 0.6 Co 0.2 Mn 0.2 . The anode material of the present invention is selected from at least one of artificial graphite, natural graphite, lithium titanate, silicon-carbon composite material, and silicon monoxide. As an example, the anode material is artificial graphite, but it is not limited thereto.

[0011] The non-aqueous electrolyte of the present invention includes a lithium salt, an organic solvent, and an additive. The lithium salt is selected from at least one of lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethylsulfonyl)imide (LiTFSI), lithium bis(oxalato)borate (LiBOB), lithium difluorophosphate (LiPO2F2), lithium fluorosulfonate (LiSO2F), lithium difluorooxalate borate, lithium lower aliphatic carboxylate, lithium difluorodioxalate phosphate, lithium bis(fluorosulfonyl)imide, lithium chloroborane, and lithium tetraphenylborate. As an example, the lithium salt is lithium hexafluorophosphate (LiPF6), but it is not limited thereto. Further, the lithium salt is a mixture of lithium hexafluorophosphate and lithium bis(oxalato)borate, but it is not limited thereto.

[0012] Specifically, by mass percentage, the mass percentage of the lithium salt in the non-aqueous electrolyte of the present invention is 5 - 25%, further, the mass percentage of the lithium salt in the non-aqueous electrolyte is 8 - 20%, more preferably, the mass percentage of the lithium salt in the non-aqueous electrolyte is 10 - 15%. As an example, the mass percentage of the lithium salt in the non-aqueous electrolyte can be, but is not limited to, 5%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 20%, 22%, 24%, 25%.

[0013] The organic solvent of the present invention is selected from at least one of carboxylic acid esters, carbonates, and ether compounds.

[0014] Specifically, the carboxylic acid ester includes, but is not limited to, at least one of γ-butyrolactone, γ-valerolactone, δ-valerolactone, methyl acetate (MA), ethyl acetate (EA), ethyl propionate (EP), butyl acetate (n-Ba), propyl propionate (n-PP), and butyl propionate. The carbonate ester includes, but is not limited to, at least one of ethylene carbonate (EC), propylene carbonate, butylene carbonate (BC), pentylene carbonate, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl n-propyl carbonate, ethyl n-propyl carbonate, and propylene carbonate (PC). The ether compounds include, but are not limited to, at least one of 1,3-dioxolane (DOL), 1,4-dioxolane (DX), crown ether, tetrahydrofuran (THF), 2-methyltetrahydrofuran (2-CH3-THF), 2-trifluoromethyltetrahydrofuran (2-CF3-THF), dimethoxymethane, diethoxymethane, ethoxymethoxymethane, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, and diethylene glycol dimethyl ether.

[0015] Specifically, the mass percentage of the organic solvent of the present invention in the non-aqueous electrolyte is 65-90%. Preferably, the mass percentage of the non-aqueous organic solvent in the non-aqueous electrolyte is 75-89%. More preferably, the mass percentage of the non-aqueous organic solvent in the non-aqueous electrolyte is 78-88%. By way of example, the mass percentage of the non-aqueous organic solvent in the non-aqueous electrolyte may be, but is not limited to, 60%, 65%, 75%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, or 90%.

[0016] The non-aqueous electrolyte of the present invention further comprises an auxiliary agent, which is selected from at least one of fluoroethylene carbonate (FEC), vinylene carbonate (VC), 1,3-propane sultone (PS), diethylene sulfate (DTD), 1,3-propylene glycol cyclic sulfate (PCS), 1,4-butane sultone, triallyl phosphate (TAP), and succinic anhydride.

[0017] Specifically, the mass percentage of the additive in the non-aqueous electrolyte is 0.1% to 10%. Preferably, the mass percentage of the additive in the non-aqueous electrolyte is 0.1% to 10%. As an example, the mass percentage of the additive in the non-aqueous electrolyte can be, but is not limited to, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9%, and 10%.

[0018] The additive of the present invention comprises an oxazolone compound represented by Formula 4 and at least one cyclic sulfonic anhydride compound selected from Formula 1, Formula 2 and Formula 3.

[0019]

[0020] wherein R1 to R7 are independently selected from hydrogen atoms, halogen atoms, substituted or unsubstituted C1 to C 10 Alkyl, substituted or unsubstituted C2 to C 10 Alkenyl, substituted or unsubstituted C2 to C 10 Alkynyl, R8~R 10 are independently selected from hydrogen atoms, amino groups, X groups, substituted or unsubstituted C1 to C 10 Alkyl, substituted or unsubstituted C2 to C 10 Alkenyl, substituted or unsubstituted C2 to C 10 Alkynyl, the structure of the X group is shown in Formula 5, * represents the connecting end, .

[0021] Furthermore, R1 to R7 are each independently selected from a hydrogen atom, a substituted or unsubstituted C1 to C6 alkyl group, and when substituted, the substituent is selected from at least one halogen atom, R8 to R9 are each independently selected from a hydrogen atom, an amino group, R 10 is selected from a hydrogen atom or an X group.

[0022] Furthermore, the cyclic sulfonic anhydride compound is selected from at least one of compounds 1 to 4: .

[0023] Among them, the CAS of compound 1 is 4720-58-5, the CAS of compound 2 is 1234622-63-9, the CAS of compound 3 is 1562-04-5, and the CAS of compound 4 is 4378-87-4.

[0024] Specifically, the mass percentage of the cyclic sulfonic anhydride compound in the non-aqueous electrolyte is 0.05% to 5%. Preferably, the mass percentage of the cyclic sulfonic anhydride compound in the non-aqueous electrolyte is 0.1% to 2%. More preferably, the mass percentage of the sulfonic anhydride compound in the non-aqueous electrolyte is 0.1% to 1%. By way of example, the mass percentage of the cyclic sulfonic anhydride compound in the non-aqueous electrolyte can be, but is not limited to, 0.05%, 0.1%, 0.2%, 0.4%, 0.5%, 0.6%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%. The mass percentage of the oxazolone compound in the non-aqueous electrolyte is 0.05% to 5%.

[0025] Furthermore, the oxazolone compound is selected from at least one of compounds 5 to 8: .

[0026] Among them, the CAS of compound 5 is 27584-70-9, the CAS of compound 7 is 832133-98-9, and the CAS of compound 8 is 59581-66-7. The preparation of compound 6 can include cooling 2 mol of oxazol-2-one to 0°C in tetrahydrofuran, adding 1 mol of sulfonyl chloride dropwise to the reaction flask, stirring and reacting for 1 hour, and then adding 2.2 mol of triethylamine acid binding agent dropwise to produce a white precipitate, then heating to 20-30°C and continuing to stir and react for 1 hour. After completion, filtering, concentrating the filtrate to remove the solvent, and then distilling to obtain compound 6 with a purity yield of 97%. Hydrogen spectrum: 1H NMR (400 MHz, CDCl3): 2.61-2.62 (d, 2H), 2.74-2.75 (d, 2H), carbon spectrum 13C NMR (400 MHz, CDCl3): δ 104.4 (s, O - CH), 115.9 (s, N - CH), 512.3 (s, O=C). The synthesis route can be shown as follows: .

[0027] Specifically, the mass percentage of the oxazolone compound in the non-aqueous electrolyte is 0.05%~5%. Preferably, the mass percentage of the oxazolone compound in the non-aqueous electrolyte is 0.1%~4%. More preferably, the mass percentage of the oxazolone compound in the non-aqueous electrolyte is 0.5%~2%. As an example, the mass percentage of the oxazolone compound in the non-aqueous electrolyte can be, but is not limited to, 0.05%, 0.1%, 0.2%, 0.4%, 0.5%, 0.6%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and 5%.

[0028] To better illustrate the purpose, technical solutions and beneficial effects of the present invention, the purpose, technical solutions and beneficial effects of the present invention are further illustrated by specific examples below, but do not constitute any limitation to the present invention. If specific conditions are not specified in the examples, the experiments can be carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be obtained commercially.

[0029] Example 1 (1) Preparation of non-aqueous electrolyte Under an argon atmosphere and in a vacuum glove box with a moisture content of <1ppm, ethylene carbonate (EC) and ethyl methyl carbonate (EMC) were mixed in a weight ratio of EC:EMC=3:7. Then, additives were added, dissolved, and stirred thoroughly, and LiPF6 was added. After mixing evenly, a non-aqueous electrolyte was obtained.

[0030] (2) Preparation of positive electrode LiNi cobalt manganese oxide material 0.6 Co 0.2 Mn 0.2 , adhesive PVDF and conductive agent SuperP are evenly mixed in a mass ratio of 96:2.5:1.5 to form a lithium secondary battery positive electrode slurry with a certain viscosity. The mixed slurry is coated on both sides of an aluminum foil, dried, and rolled to obtain a positive electrode sheet.

[0031] (3) Preparation of negative electrode The negative electrode artificial graphite material, adhesive PVDF and conductive agent SuperP are evenly mixed in a mass ratio of 90:2:8 to prepare a lithium secondary battery negative electrode slurry with a certain viscosity. The mixed slurry is coated on both sides of the copper foil, dried and rolled to obtain the negative electrode sheet.

[0032] (4) Preparation of lithium-ion batteries The positive electrode sheet, separator, and negative electrode sheet are stacked in order and then stacked as needed. After the tabs are welded, they are placed in the aluminum-plastic film outer packaging of the battery. The prepared non-aqueous electrolyte is injected into the dried bare cell. The cells are then vacuum packaged, allowed to stand, formed (charged at a constant current of 0.05C to 3.9V, then at a constant current of 0.1C to 4.5V), shaped, and tested for capacity, resulting in a 1Ah soft-pack lithium secondary battery.

[0033] The non-aqueous electrolyte formulations of Examples 1-23 and Comparative Examples 1-3 are shown in Table 1. The steps for preparing the electrolytes and manufacturing the batteries are the same as those of Example 1.

[0034] Table 1 Formula of non-aqueous electrolyte

[0035] The lithium-ion batteries prepared in Examples 1 to 23 and Comparative Examples 1 to 3 were subjected to high-temperature storage tests and high-temperature cycle tests, respectively. The specific test conditions are as follows. The performance test results are shown in Table 2.

[0036] Lithium-ion battery high temperature storage performance test At room temperature (25°C), the lithium-ion battery is charged and discharged at 0.3C / 0.3C (the battery discharge capacity is recorded as C0), with an upper voltage of 4.5V; the battery is placed in a 60°C oven for 30 days, the battery is taken out, and the battery is placed in a 25°C environment and discharged at 0.3C, with the discharge capacity recorded as C1; then the lithium-ion battery is charged and discharged at 0.3C / 0.3C (the battery discharge capacity is recorded as C2), and the capacity retention rate and capacity recovery rate of the lithium-ion battery are calculated using the following formula: Capacity retention rate = (C1 / C0) × 100% Capacity recovery rate = (C2 / C0) × 100% Lithium-ion battery high temperature cycle performance test Place the lithium-ion battery in a 45°C constant temperature box and let it stand for 30 minutes to allow the lithium-ion battery to reach a constant temperature. Then charge it at a constant current of 0.33C to a voltage of 4.5V, then charge it at a constant voltage of 4.5V to a current of 0.05C, and then discharge it at a constant current of 0.33C to a voltage of 3V. Record the first discharge capacity of the battery as C0, which is one charge and discharge cycle. Then, charge and discharge it at 1C / 1C for 1000 cycles at 45°C, record the discharge capacity as C1, and use the following formula to calculate the capacity retention rate of the lithium-ion battery.

[0037] Capacity retention rate = (C1 / C0) × 100% Internal resistance test Place the separated lithium-ion battery in a 25°C constant temperature chamber and let it rest for 30 minutes to allow the battery to reach a constant temperature. Charge the battery at a constant current of 1C to a voltage of 4.5V, then charge it at a constant voltage of 4.5V to a current of 0.05C. Discharge it at a constant current of 1C to a voltage of 3V. Record the battery's first discharge capacity as C0. This constitutes one charge-discharge cycle. Then, perform 1C / 1C charge and discharge at 25°C for three weeks, discharging it to 0.5C0. Remove the battery and test its DC internal resistance, R.

[0038] Table 2 Lithium-ion battery performance test results

[0039] As shown in the test results in Table 2, the lithium-ion batteries of Examples 21 to 23 have better high-temperature storage performance and high-temperature cycle performance than those of Comparative Example 1. This may be because the non-aqueous electrolyte of the present invention uses cyclic sulfonic anhydride compounds and oxazolone compounds as additives, wherein the cyclic sulfonic anhydride compound is an unsaturated cyclic compound with a reduction potential of ~1.5V (vs. Li / Li +), which can preferentially undergo reduction and decomposition on the negative electrode surface to form a stable SEI film, which can effectively reduce the side reactions between the electrolyte and the negative electrode material and improve the structural stability of the negative electrode material. However, the steric hindrance of its cyclic rigid structure is large, the viscosity of the electrolyte increases, and the reaction rate is reduced, thereby increasing the battery impedance, which has a deteriorating effect on the high-temperature storage and high-temperature cycle performance of the battery. Therefore, the present invention further introduces oxazolone compounds into the non-aqueous electrolyte, which has a reduction potential of about 1.0V and can preferentially undergo a reduction reaction in the solvent on the negative electrode surface to form a SEI film rich in Li3N / Li2O, synergistically regulate the components of the solid electrolyte membrane, reduce the interfacial impedance, and reduce the decomposition and gas production of the electrolyte at high temperature, thereby improving the high-temperature storage performance of the battery. At the same time, the polar structures (such as carbonyl groups and nitrogen heterocycles) contained in the oxazolone compounds can enhance the dissociation of lithium salts (such as LiPF6) and improve Li + The concentration of cyclic sulfonic acid anhydride compounds and oxazolone compounds can effectively improve the storage and cycling performance of lithium-ion batteries at high temperatures.

[0040] It can be seen from Example 23 and Comparative Examples 2-3 that when only Compound 3 or Compound 6 is used, the high-temperature storage and cycle performance of the lithium-ion battery cannot be taken into account at the same time, and the improvement effect is lower than that of Example 23. Therefore, the present invention introduces compounds represented by Structural Formula I and Structural Formula II into the lithium-ion battery electrolyte, thereby increasing the ion transfer rate of the lithium-ion battery, forming a stable SEI film, reducing the internal resistance of the battery, and improving the high-temperature storage performance and high-temperature cycle performance of the lithium-ion battery.

[0041] The test results of Examples 1 to 16 show that the performance of Compound 1 and Compound 6 is even better when used together. This is likely because the unsaturated cyclic sulfonic anhydride compound shown in Compound 1 can effectively accelerate the lithium ion transmission rate. The passivation film formed by the cyclic sulfonic anhydride electrolyte additive on the graphite negative electrode surface can reduce the co-intercalation of solvent molecules, which is beneficial for the deintercalation of lithium ions. In addition, the sulfonic anhydride reductively decomposes to form a sulfur-rich inorganic SEI film, which can effectively reduce side reactions between the electrolyte and the negative electrode material. The oxazol-2-one salt compound shown in Compound 6 can synergistically regulate the components of the solid electrolyte membrane. After the carbon-nitrogen double bond in the oxazol-2-one compound captures electrons on the negative electrode surface, it will form an SEI film with polymer chain segments through electrochemical reduction polymerization. This polymer segment has good elastic properties and can withstand the volume changes of the negative electrode material during the charge and discharge process without breaking. Compound 6 preferentially undergoes oxidation and reduction, and its nitrogen-containing heterocycle and sulfonyl groups form a thin, conductive, nitrogen- and sulfur-rich cathode electrolyte interface / solid electrolyte interface film on the ternary cathode and graphite anode. This inhibits transition metal ion dissolution and lithium dendrite growth, improving the structural stability of the positive and negative electrodes. The combination of compound 1 and compound 6 further enhances the stability of the SEI film, effectively preventing the continuous reductive decomposition of the electrolyte and the loss of active lithium, thereby improving the high-temperature performance of lithium-ion batteries at a high voltage of 4.5V.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A non-aqueous electrolyte comprising a lithium salt, an organic solvent and an additive, characterized in that: The additive comprises an oxazolone compound as shown in Formula 4 and at least one cyclic sulfonic anhydride compound selected from Formula 1, Formula 2 and Formula 3, wherein R1 to R7 are each independently selected from a hydrogen atom, a halogen atom, a substituted or unsubstituted C1 to C 10 Alkyl, substituted or unsubstituted C2 to C 10 Alkenyl, substituted or unsubstituted C2 to C 10 Alkynyl, R8~R 10 are independently selected from hydrogen atoms, amino groups, X groups, substituted or unsubstituted C1 to C 10 Alkyl, substituted or unsubstituted C2 to C 10 Alkenyl, substituted or unsubstituted C2 to C 10 Alkynyl, the structure of the X group is shown in Formula 5, * represents the connecting end, 。 2. The non-aqueous electrolyte according to claim 1, wherein R1-R7 are each independently selected from a hydrogen atom, a substituted or unsubstituted C1 to C6 alkyl group, and when substituted, the substituent is selected from at least one halogen atom, R8-R9 are each independently selected from a hydrogen atom, an amino group, R 10 is selected from a hydrogen atom or an X group.

3. The non-aqueous electrolyte according to claim 1 or 2, wherein The cyclic sulfonic anhydride compound is selected from at least one of compounds 1 to 4: 。 4. The non-aqueous electrolyte according to claim 1 or 2, wherein The oxazolone compound is selected from at least one of compounds 5 to 8: 。 5. The non-aqueous electrolyte according to claim 1 or 2, wherein The mass percentage of the cyclic sulfonic anhydride compound in the non-aqueous electrolyte is 0.05%-5%, and the mass percentage of the oxazolone compound in the non-aqueous electrolyte is 0.05%-5%.

6. The non-aqueous electrolyte according to claim 1 or 2, wherein The mass percentage of the cyclic sulfonic anhydride compound in the non-aqueous electrolyte is 0.1%-2%, and the mass percentage of the oxazolone compound in the non-aqueous electrolyte is 0.1%-4%.

7. The non-aqueous electrolyte according to claim 1 or 2, wherein The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium trifluoromethanesulfonate, lithium bis(trifluoromethanesulfonyl imide), lithium difluorophosphate, lithium fluorosulfonate, lithium bis(oxalatoborate), lithium difluorooxalatoborate, lithium lower aliphatic carboxylate, lithium difluorobis(oxalatophosphate), lithium bis(fluorosulfonyl imide), lithium chloroborane, and lithium tetraphenylborate.

8. The non-aqueous electrolyte according to claim 1 or 2, wherein The organic solvent is selected from at least one of carboxylic acid esters, carbonates and ether compounds.

9. A lithium-ion battery, characterized in that The invention comprises a positive electrode material, a negative electrode material and the non-aqueous electrolyte according to any one of claims 1 to 8.

10. The lithium-ion battery according to claim 9, wherein The positive electrode material is selected from at least one of nickel-cobalt-manganese oxide and nickel-cobalt-aluminum oxide.

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