Lithium ion battery with silicon-carbon negative electrode

Abstract

The invention discloses a silicon carbon negative electrode lithium ion battery, which comprises a positive plate, a negative plate and a non-aqueous electrolyte, the negative plate comprises a negative electrode active material, the negative electrode active material comprises a silicon carbon composite material and a transition metal element, the non-aqueous electrolyte comprises a first additive, and the first additive is a compound having a structure of a chemical formula I, r1 and R2 are respectively and independently selected from a carbonyl group, an ester group, an alkyl group with 1 to 12 carbon atoms, a halogenated alkyl group with 1 to 12 carbon atoms, an alkenyl group with 2 to 12 carbon atoms, an alkynyl group with 2 to 12 carbon atoms, a cyclic alkyl group with 3 to 12 carbon atoms and an alkyl phenyl group with 1 to 12 carbon atoms. The lithium ion battery with the silicon-carbon negative electrode has good fast charge cycle performance and storage performance. The chemical formula I of the # imgabs0 # is shown in the specification.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and particularly to a silicon-carbon anode lithium-ion battery. Background Art

[0002] Graphite anode materials are the most widely commercialized anode materials at present, and they have advantages such as high electrical conductivity and stability. However, the energy density of graphite anodes has approached its theoretical maximum value (372 mAh / g), so the optimization space for the energy density of lithium-ion batteries based on graphite anodes is relatively limited. With the wide application of lithium-ion batteries in fields such as new energy vehicles, energy storage systems, and consumer electronics, the demand for battery energy density is getting higher and higher, and graphite anodes are difficult to meet this demand. Silicon anodes have an extremely high theoretical specific capacity. The theoretical specific capacity of elemental silicon anodes is as high as 4200 mAh / g, more than 10 times that of graphite anodes; while the theoretical specific capacity of silicon monoxide anodes also reaches 2600 mAh / g, much higher than that of graphite anodes. In addition, silicon anodes also have advantages such as a low de-lithiation potential (<0.5 V), environmental friendliness, rich reserves, and low cost. These advantages make silicon anodes an ideal choice for improving the energy density of lithium-ion batteries. However, problems such as the volume expansion of silicon materials during charge and discharge and the low electronic conductivity of silicon materials themselves have always restricted the improvement of material performance and also brought certain resistance to the market development of silicon.

[0003] Therefore, there is an urgent need for a silicon-carbon anode lithium-ion battery to solve the deficiencies of the prior art. Summary of the Invention

[0004] In view of the above problems, the purpose of the present invention is to provide a silicon-carbon anode lithium-ion battery, which has good fast charge cycle performance and storage performance.

[0005] To achieve the above purpose, the present invention provides a silicon-carbon anode lithium-ion battery, including a positive electrode sheet, a negative electrode sheet, and a non-aqueous electrolyte. The negative electrode sheet includes a negative electrode active material, and the negative electrode active material includes a silicon-carbon composite material and a transition metal element. The non-aqueous electrolyte includes a first additive, and the first additive is a compound having the structure of Chemical Formula Ⅰ:

[0006] Wherein, R1 and R2 each independently selected from a carbonyl group, an ester group, an alkyl group having 1 to 12 carbon atoms, a halogenated alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, a cyclic hydrocarbon group having 3 to 12 carbon atoms, an alkylphenyl group having 1 to 12 carbon atoms.

[0007] Compared with the prior art, the negative electrode active material of the present invention includes a silicon-carbon composite material and a transition metal element. The introduction of the transition metal element can improve the electronic conductivity of the silicon-carbon composite material, thereby enhancing the overall fast charging performance of the silicon-carbon negative electrode. Moreover, the transition metal element can partially form an alloy state with silicon, thus reducing the formation of lithium-silicon alloy and further reducing the thickness expansion of the battery, which can further improve the fast charging performance of the battery. At the same time, the non-aqueous electrolyte of the present invention also includes a first additive, which acts as a sacrificial substance and can form a protective layer on the surface of the silicon-carbon negative electrode, reducing the consumption of other effective components in the non-aqueous electrolyte. And the first additive contains a fluorosulfonyl functional group. Due to the strong electron-withdrawing property of the fluorosulfonyl group, when it forms a negative ion with other atoms or groups, it can effectively disperse the negative charge, making the negative ion more stable. The fluorosulfonyl functional group can promote more transition metal elements to enter the interface of the silicon-carbon negative electrode, increasing the proportion of its participation in alloying, thereby alleviating the volume expansion effect of silicon. Therefore, through the synergistic effect between the negative electrode active material and the first additive, the fast charging cycle and storage performance of the silicon-carbon negative electrode system are improved. Further, R1 and R2 are each independently selected from a carbonyl group, an ester group, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C2-C6 alkenyl group, a C2-C6 alkynyl group, a C5-C10 cyclic hydrocarbon group, and a C1-C6 alkylphenyl group.

[0008] Further, the transition metal element is selected from at least one of Fe, Co, Ni, Ti, Ge, and Mn.

[0009] Further, the mass percentage of the transition metal element in the negative electrode active material is 0.01% - 1%.

[0010] Further, the mass percentage of silicon in the silicon-carbon composite material is 1% - 20%.

[0011] Further, the first additive is selected from at least one of Formula I-1 to Formula I-10:

[0012] .

[0013] Further, the mass percentage of the first additive in the non-aqueous electrolyte is 0.05% - 10%.

[0014] Further, the non-aqueous electrolyte includes a second additive, and the second additive is selected from at least one of fluoroethylene carbonate, ethyl fluoroacetate, dimethyl difluorocarbonate, and ethyl methyl fluorocarbonate.

[0015] Further, the mass percentage of the second additive in the non-aqueous electrolyte is 12% - 22%.

[0016] Further, the non-aqueous electrolyte includes a lithium salt, and the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium trifluoromethanesulfonate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium difluoro bis(oxalato)phosphate, lithium fluorosulfonate, and lithium bis(fluorosulfonyl)imide.

[0017] Further, the non-aqueous electrolyte includes a non-aqueous organic solvent, and the non-aqueous organic solvent is selected from at least one of carbonate organic solvents, carboxylate organic solvents, and ether organic solvents.

[0018] Further, the positive electrode sheet includes a positive electrode active material, and the positive electrode active material is a lithium cobaltate material, a lithium iron phosphate material, a nickel cobalt manganese oxide, or a nickel cobalt aluminum oxide. Detailed implementation manners

[0019] The silicon-carbon negative electrode lithium ion battery of the present invention includes a positive electrode sheet, a negative electrode sheet, and a non-aqueous electrolyte. Among them, the positive electrode sheet includes a positive electrode active material, and the positive electrode active material is a lithium cobaltate material, a lithium iron phosphate material, a nickel cobalt manganese oxide, or a nickel cobalt aluminum oxide. Specifically, the lithium cobaltate material is lithium cobaltate or lithium cobaltate modified by doping and coating, the lithium iron phosphate material is lithium iron phosphate or lithium iron phosphate modified by doping and coating, and the chemical formula of the nickel cobalt manganese oxide is LiNi x Co y Mn z M (1-x-y-z) O2, and the chemical formula of the 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 positive electrode active material is lithium cobalt oxide (LiCoO2). The negative electrode sheet includes a negative electrode active material, and the negative electrode active material includes a silicon-carbon composite material and a transition metal element. Among them, the mass percentage of silicon in the silicon-carbon composite material is 1% - 20%, preferably, the mass percentage of silicon in the silicon-carbon composite material is 1% - 10%, and more preferably, the mass percentage of silicon in the silicon-carbon composite material is 2% - 5%. As an example, the mass percentage of silicon in the silicon-carbon composite material can be but not limited to 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 18%, 20%. The transition metal element is selected from at least one of Fe, Co, Ni, Ti, Ge, and Mn. As an example, the transition metal element is selected from any one or a combination of two or more of Ni, Co, Mn, or the transition metal element is selected from any one or a combination of two or more of Ni, Co, Ti, Fe. The mass percentage of the transition metal element in the negative electrode active material is 0.01% - 1%. As an example, the mass percentage of the transition metal element in the negative electrode active material can be but not limited to 0.01%, 0.02%, 0.04%, 0.06%, 0.08%, 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, 1%. When the mass percentage of the transition metal element is too high, it will increase the self-discharge behavior of the negative electrode and reduce the performance of the battery. When the mass percentage of the transition metal element is too low, it cannot participate well in the alloy reaction, and the improvement of the performance is relatively limited.

[0020] The non-aqueous electrolyte of the present invention includes a lithium salt, a non-aqueous organic solvent, and an additive. Among them, the lithium salt is selected from at least one of lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium trifluoromethanesulfonate (LiCF3SO3), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium bis(oxalato)borate (LiBC4O8), lithium difluorophosphate (LiPO2F2), lithium difluoro(oxalato)borate (LiBF2C2O4), lithium difluoro(dioxalato)phosphate (LiDFBP), lithium fluorosulfonate (LiSO2F), and lithium bis(fluorosulfonyl)imide (LiFSI). Specifically, the mass percentage of the lithium salt in the non-aqueous electrolyte is 5% - 20%, preferably, the mass percentage of the lithium salt in the non-aqueous electrolyte is 6% - 15%. As an example, the mass percentage of the lithium salt in the non-aqueous electrolyte can be but not limited to 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 18%, 20%.

[0021] The non-aqueous organic solvent is selected from at least one of carbonate organic solvents, carboxylate organic solvents, and ether organic solvents. Specifically, the carbonate organic solvents include, but are not limited to, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), pentylene carbonate, vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), etc.; the carboxylate organic solvents include, but are not limited to, fluorinated carboxylate, butyl acetate (n-Ba), γ-butyrolactone (γ-Bt), n-propyl propionate (n-PP), ethyl propionate (EP), and ethyl butyrate (Eb), etc.; the ether organic solvents include, but are not limited to, fluorinated ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether, etc. The mass percentage of the non-aqueous organic solvent in the non-aqueous electrolyte is 60% - 90%. As an example, the mass percentage of the non-aqueous organic solvent in the non-aqueous electrolyte can be, but is not limited to, 60%, 65%, 70%, 72%, 74%, 75%, 76%, 78%, 80%, 82%, 84%, 85%, 86%, 88%, 90%.

[0022] The additive includes a first additive, and the first additive is a compound having the structure of Chemical Formula Ⅰ:

[0023] Among them, R1 and R2 each independently selected from carbonyl, ester group, C1 - C12 alkyl, C1 - C12 haloalkyl, C2 - C12 alkenyl, C2 - C12 alkynyl, C3 - C12 cycloalkyl, C1 - C12 alkylphenyl. Further, R1 and R2 each independently selected from carbonyl, ester group, C1 - C6 alkyl, C1 - C6 haloalkyl, C2 - C6 alkenyl, C2 - C6 alkynyl, C5 - C10 cycloalkyl, C1 - C6 alkylphenyl. The mass percentage of the first additive in the non-aqueous electrolyte is 0.05% - 10%. Preferably, the mass percentage of the first additive in the non-aqueous electrolyte is 0.1% - 5%. More preferably, the mass percentage of the first additive in the non-aqueous electrolyte is 0.5% - 3%. As an example, the mass percentage of the first additive in the non-aqueous electrolyte can be, but is not limited to, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%. When the mass percentage of the first additive is too high, it will increase the viscosity of the non-aqueous electrolyte and reduce the fast charging performance of the battery. As an example, the first additive can be selected from at least one of Formula Ⅰ-1 to Formula Ⅰ-10:

[0024]

[0025] The additive of the present invention further includes a second additive, and the second additive is selected from at least one of fluoroethylene carbonate (FEC), ethyl fluoroacetate (TFA), diethyl fluoroacetate (DFEA), and fluoroethyl methyl carbonate (FEMC). The mass percentage of the second additive in the non-aqueous electrolyte is 12% - 22%. Preferably, the mass percentage of the second additive in the non-aqueous electrolyte is 15% - 20%. As an example, the mass percentage of the second additive in the non-aqueous electrolyte can be, but is not limited to, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%.

[0026] To better illustrate the purpose, technical solution, and beneficial effects of the present invention, the present invention will be further described below in conjunction with specific embodiments. It should be noted that the methods described in the following embodiments are further explanatory descriptions of the present invention and should not be regarded as limitations on the present invention. For those conditions not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. For reagents or instruments whose manufacturers are not specified, they are all conventional products that can be obtained through commercial purchase.

[0027] Example 1 Preparation of non-aqueous electrolyte: In a glove box filled with nitrogen (O2 < 2 ppm, H2O < 3 ppm), ethylene carbonate (EC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC) were mixed evenly according to a mass ratio of 1:2:1 to obtain 84.8 g of non-aqueous organic solvent. 0.2 g of Compound 1 was added to obtain a mixed solution. The solution was sealed and packed and placed in a freezer (-4°C) for 2 hours and then taken out. In a glove box filled with nitrogen (O2 < 2 ppm, H2O < 3 ppm), 15 g of lithium hexafluorophosphate was slowly added to the mixed solution to prepare an electrolyte solution.

[0028] Preparation of positive electrode sheet: LiCoO2, conductive agent SuperP, binder PVDF, and carbon nanotubes (CNT) were mixed evenly according to a mass ratio of 96.5:1.5:1:1 to prepare a lithium-ion battery positive electrode paste with a certain viscosity, which was coated on aluminum foil used as a current collector, and the coating amount was 324 g / m 2 , dried at 85°C and then cold-pressed; then trimmed, sliced, and slit. After slitting, it was dried at 85°C for 4 hours under vacuum conditions, and the electrode tabs were welded to prepare a lithium-ion battery positive electrode sheet that met the requirements.

[0029] Preparation of the negative electrode sheet: A silicon-carbon composite material (with a silicon content of 10%) and NiO are mixed at a mass ratio of 99.5:0.5, and then made into a slurry with a conductive agent SuperP, a thickening agent CMC, and an adhesive SBR (styrene-butadiene rubber latex) at a mass ratio of 95:1.5:1.0:2.5. After mixing evenly, the prepared slurry is coated on both sides of a copper foil, dried, and rolled to make a lithium-ion battery negative electrode sheet that meets the requirements.

[0030] Preparation of the lithium-ion battery: The positive electrode sheet, negative electrode sheet, and separator prepared according to the above process are made into a lithium-ion battery with a thickness of 4.7 mm, a width of 55 mm, and a length of 60 mm through a stacking process, vacuum baked at 75 °C for 10 h, and the electrolyte prepared in 1.1 is injected. After standing for 24 h, it is charged at a constant current of 0.lC (180 mA) to 4.45 V, and then charged at a constant voltage of 4.45 V until the current drops to 0.05C (90 mA); then discharged at 0.2C (180 mA) to 3.0 V, and the charge-discharge process is repeated 2 times. Finally, the battery is charged to 3.8 V at 0.2C (180 mA) to complete the production of the lithium-ion battery.

[0031] Examples 2 to 13 The difference between the silicon-carbon negative electrode lithium-ion batteries of Examples 2 to 13 and Example 1 is only the non-aqueous electrolyte, and the rest are the same. The formulations of the non-aqueous electrolytes of Examples 2 to 13 are shown in Table 1.

[0032] Example 14 The difference between Example 14 and Example 1 is only the different preparation of the negative electrode sheet and the non-aqueous electrolyte, and the rest are the same. The preparation of the negative electrode sheet in Example 14 includes: A silicon-carbon composite material (with a silicon content of 10%) and Co(OH)2 are mixed at a mass ratio of 99.5:0.5:0.3, and then made into a slurry with a conductive agent SuperP, a thickening agent CMC, and an adhesive SBR (styrene-butadiene rubber latex) at a mass ratio of 95:1.5:1.0:2.5. After mixing evenly, the prepared slurry is coated on both sides of a copper foil, dried, and rolled to make a lithium-ion battery negative electrode sheet that meets the requirements. The formulation of the non-aqueous electrolyte in Example 14 is shown in Table 1.

[0033] Example 15 Example 15 is only different from Example 1 in the preparation of the negative electrode sheet and the non-aqueous electrolyte, and the rest are the same. The preparation of the negative electrode sheet in Example 15 includes: mixing a silicon-carbon composite material (silicon content is 10%) and Mn(OH)₂ in a mass ratio of 99.7:0.3, and then making a slurry with a conductive agent SuperP, a thickening agent CMC, and an adhesive SBR (styrene-butadiene rubber latex) in a mass ratio of 95:1.5:1.0:2.5. After mixing evenly, coat the mixed slurry on both sides of the copper foil, and then dry and roll it to make a lithium-ion battery negative electrode sheet that meets the requirements. The formula of the non-aqueous electrolyte in Example 15 is shown in Table 1.

[0034] Comparative Examples 1 - 2 Comparative Examples 1 - 2 are only different from Example 1 in the non-aqueous electrolyte, and the rest are the same. The formula of the non-aqueous electrolyte in Comparative Examples 1 - 2 is shown in Table 1.

[0035] Comparative Example 3 Comparative Example 3 is different from Example 1 only in the preparation of the negative electrode sheet, and the rest are the same. The preparation of the negative electrode sheet in Comparative Example 3 includes: mixing a silicon-carbon composite material (silicon content is 10%) and NiO in a mass ratio of 98.5:1.5, and then making a slurry with a conductive agent SuperP, a thickening agent CMC, and an adhesive SBR (styrene-butadiene rubber latex) in a mass ratio of 95:1.5:1.0:2.5. After mixing evenly, coat the mixed slurry on both sides of the copper foil, and then dry and roll it to make a lithium-ion battery negative electrode sheet that meets the requirements. The formula of the non-aqueous electrolyte in Comparative Example 3 is shown in Table 1.

[0036] Comparative Example 4 Comparative Example 4 is different from Example 1 only in the preparation of the negative electrode sheet, and the rest are the same. The preparation of the negative electrode sheet in Comparative Example 4 includes: making a slurry with a silicon-carbon composite material (silicon content is 10%), a conductive agent SuperP, a thickening agent CMC, and an adhesive SBR (styrene-butadiene rubber latex) in a mass ratio of 95:1.5:1.0:2.5. After mixing evenly, coat the mixed slurry on both sides of the copper foil, and then dry and roll it to make a lithium-ion battery negative electrode sheet that meets the requirements. The formula of the non-aqueous electrolyte in Comparative Example 4 is shown in Table 1.

[0037] Table 1 Non-aqueous electrolyte components of each example and comparative example

[0038] Electrochemical performance tests were carried out on the silicon-carbon negative electrode lithium-ion batteries made in Examples 1 - 15 and Comparative Examples 1 - 4. The specific test conditions are as follows, and the test results are shown in Table 2.

[0039] High-temperature cycling performance Place the lithium-ion battery in an incubator at 45 °C and let it stand for 30 minutes to bring the lithium-ion battery to a constant temperature. Charge it at a constant current of 3C until the voltage reaches 4.45V, then charge it at a constant voltage of 4.45V until the current reaches 0.05C, and then discharge it at a constant current of 1C until the voltage reaches 3.0V. Record the initial discharge capacity of the battery as C0. This is one charge-discharge cycle. Then, perform 3C / 1C charging and discharging at 45 °C for 300 cycles, and record the discharge capacity as C1.

[0040] Capacity retention rate = C1 / C0 × 100% High-temperature storage test of lithium-ion batteries Under normal temperature (25 °C) conditions, perform one 0.3C / 0.3C charge and discharge on the lithium-ion battery (the discharge capacity of the battery is recorded as C0), with the upper limit voltage being 4.5V; then charge the battery to 4.5V under a constant current and constant voltage condition of 0.5C, measure the thickness of the battery (the thickness is recorded as D0), place the battery in an oven at 85 °C for 6h, take out the battery and measure the thickness of the battery (the thickness is recorded as D1), place the battery in an environment of 25 °C, and perform 0.3C discharge, with the discharge capacity recorded as C1; then perform one 0.3C / 0.3C charge and discharge on the lithium-ion battery (the discharge capacity of the battery is recorded as C2), and calculate the capacity retention rate, capacity recovery rate, and thickness expansion rate of the lithium-ion battery using the following formula: Capacity retention rate = C1 / C0 × 100% Capacity recovery rate = C2 / C0 × 100% Thickness expansion rate = D1 / D0 × 100% Table 2 Test results of the performance of lithium-ion batteries

[0041] From the test results in Table 2, it can be seen that, compared with Comparative Examples 1-4, the electrochemical performance of Examples 1-15 is better. This may be because the negative electrode active material of the present invention includes a silicon-carbon composite material and a transition metal element. The introduction of the transition metal element can improve the electronic conductivity of the silicon-carbon composite material, thereby improving the fast charging performance of the overall silicon-carbon negative electrode. Moreover, the transition metal element can partially form an alloy state with silicon, thereby reducing the formation of lithium-silicon alloy, and further reducing the thickness expansion of the battery, which can further improve the fast charging performance of the battery. At the same time, the non-aqueous electrolyte of the present invention also includes a first additive. On the one hand, the first additive itself acts as a sacrificial substance, which can form a protective layer on the surface of the silicon-carbon negative electrode, reducing the consumption of other effective components in the non-aqueous electrolyte. And the first additive contains a fluorosulfonyl functional group, and the fluorosulfonyl functional group can promote more transition metal elements to enter the interface of the silicon-carbon negative electrode, increasing the proportion of its participation in alloying, thereby alleviating the volume expansion effect of silicon. Therefore, through the synergistic effect between the negative electrode active material and the first additive of the present invention, the fast charging cycle and storage performance of the silicon-carbon negative electrode system are improved.

[0042] In Comparative Example 2, the excessive mass of the first additive increased the viscosity of the electrolyte, thereby affecting the high-temperature fast charging cycle performance of the battery.

[0043] In Comparative Example 3, due to the excessive content of transition metal elements, it may be due to the increase in the self-discharge behavior of the negative electrode, so the performance of the battery was reduced.

[0044] The negative electrode active material in Comparative Example 4 did not contain transition metal elements, resulting in a large thickness expansion of the negative electrode material, and the high-temperature fast charging and high-temperature storage performance of the battery were both greatly reduced.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, it is not limited to the embodiments listed. Those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A silicon-carbon anode lithium-ion battery, comprising a positive electrode sheet, a negative electrode sheet, and a non-aqueous electrolyte, characterized in that, The negative electrode sheet includes a negative electrode active material, the negative electrode active material includes a silicon-carbon composite material and a transition metal element, the non-aqueous electrolyte includes a first additive, and the first additive is a compound having the structure of Chemical Formula I: Wherein, R1 and R2 are each independently selected from a carbonyl group, an ester group, an alkyl group having 1 to 12 carbon atoms, a halogenated alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, a cyclic hydrocarbon group having 3 to 12 carbon atoms, and an alkylphenyl group having 1 to 12 carbon atoms.

2. The silicon-carbon anode lithium-ion battery according to claim 1, characterized in that, R1 and R2 are each independently selected from a carbonyl group, an ester group, an alkyl group having 1 to 6 carbon atoms, a halogenated alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a cyclic hydrocarbon group having 5 to 10 carbon atoms, and an alkylphenyl group having 1 to 6 carbon atoms.

3. The silicon-carbon anode lithium-ion battery according to claim 1, characterized in that The transition metal element is selected from at least one of Fe, Co, Ni, Ti, Ge, and Mn, and the mass percentage of the transition metal element in the negative electrode active material is 0.01% to 1%.

4. The silicon-carbon anode lithium-ion battery according to claim 1, wherein The mass percentage of silicon in the silicon-carbon composite material is 1% to 20%.

5. The silicon-carbon anode lithium-ion battery according to claim 1, wherein, The first additive is selected from at least one of Formula I-1 to Formula I-10. 。 6. The silicon-carbon anode lithium-ion battery according to claim 1, characterized in that, The mass percentage of the first additive in the non-aqueous electrolyte is 0.05% to 10%.

7. The silicon-carbon anode lithium-ion battery according to claim 1, wherein, The non-aqueous electrolyte includes a second additive, the second additive is selected from at least one of fluoroethylene carbonate, ethyl fluoroacetate, dimethyl difluorocarbonate, and ethyl methyl fluorocarbonate, and the mass percentage of the second additive in the non-aqueous electrolyte is 5% to 22%.

8. The silicon-carbon anode lithium-ion battery according to claim 1, characterized in that, The non-aqueous electrolyte includes a lithium salt, and the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium trifluoromethanesulfonate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(oxalato)borate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium difluoro(dioxalato)phosphate, lithium fluorosulfonate, and lithium bis(fluorosulfonyl)imide.

9. The silicon-carbon anode lithium-ion battery according to claim 1, characterized in that, The non-aqueous electrolyte includes a non-aqueous organic solvent, and the non-aqueous organic solvent is selected from at least one of carbonate organic solvents, carboxylate organic solvents, and ether organic solvents.

10. The silicon-carbon anode lithium-ion battery according to claim 1, characterized in that, The positive electrode sheet includes a positive electrode active material, and the positive electrode active material is a lithium cobalt oxide material, a lithium iron phosphate material, a nickel cobalt manganese oxide, or a nickel cobalt aluminum oxide.

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