Non-aqueous electrolyte applied to sodium ion battery and sodium ion battery

Abstract

The invention provides a non-aqueous electrolyte applied to a sodium-ion battery and the sodium-ion battery, the non-aqueous electrolyte comprises an electrolyte, a non-aqueous organic solvent and an additive, the additive comprises an additive A and an additive B. The additive A is a phosphorus-oxygen heterocyclic compound shown in the formula 1, and the additive B is a phosphorus-oxygen heterocyclic compound shown in the formula 1. The additive B is a phenyl boron oxygen heterocyclic compound as shown in a formula 2. According to the non-aqueous electrolyte provided by the invention, the additive A and the phenyl boron oxide heterocyclic compound additive B are simultaneously added, and the two compounds have a synergistic effect, so that the wide-temperature performance of the electrolyte can be improved, the dissolution of transition metal ions of a positive electrode material can be inhibited, the cycle performance of the electrolyte at high temperature and low temperature can be improved, and the application requirements of a sodium ion battery can be met.

Description

Technical Field

[0001] This invention belongs to the field of sodium-ion battery technology, and relates to a non-aqueous electrolyte for use in sodium-ion batteries and a sodium-ion battery. Background Technology

[0002] Sodium-ion batteries, due to their abundant resources and low cost, are considered an ideal supplement and alternative to lithium-ion batteries and have received considerable attention in recent years. Their working principle is similar to that of lithium-ion batteries, but their performance faces severe challenges under extreme temperature environments.

[0003] Under high-temperature conditions, heat exacerbates the collapse of the crystal structure of the cathode material and the dissolution of transition metals, while also causing the decomposition of the solid electrolyte interfacial film on the surface of the hard carbon anode, resulting in a surge in interfacial impedance and rapid capacity decay. These bottlenecks severely limit the practical application of sodium-ion batteries, making the development of sodium-ion batteries capable of stable operation in the high-temperature range an urgent priority.

[0004] As a core component of a battery, the performance of the electrolyte directly determines the overall performance of the battery. Among the various methods, adjusting the electrolyte composition and introducing functional additives have proven to be effective strategies for improving the battery's resistance to high and low temperatures. Additives not only enhance the battery's cycle stability under extreme environments but also improve the compatibility between the electrolyte and electrode materials. Therefore, developing a novel high-temperature resistant sodium-ion battery electrolyte and its preparation method to significantly improve the battery's cycle stability under harsh temperature conditions has become a key technical challenge that urgently needs to be overcome in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a non-aqueous electrolyte for use in sodium-ion batteries and a sodium-ion battery.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] On one hand, the present invention provides a non-aqueous electrolyte for use in sodium-ion batteries. The non-aqueous electrolyte includes an electrolyte, a non-aqueous organic solvent, and additives. The additives include additive A and additive B. Additive A is a phosphorus oxide heterocyclic compound represented by Formula 1, and additive B is a phenyl boron oxide heterocyclic compound represented by Formula 2.

[0008] ;

[0009] R1, R2, R3 and R4 are independently selected from hydrogen, substituted or unsubstituted C1-C3 (e.g. C1, C2 or C3) chain alkane groups, substituted or unsubstituted phenyl groups, substituted or unsubstituted phenoxy groups or substituted or unsubstituted biphenyl groups, wherein the substituted substituents are selected from halogen atoms or C1-C3 (e.g. C1, C2 or C3) alkyl groups.

[0010] In this invention, the alkyl group of C1-C3 can be methyl, ethyl, n-propyl or isopropyl, and the halogen can be F, Cl, Br or I.

[0011] In the non-aqueous electrolyte of the present invention, additive A is a phosphorus-oxygen heterocyclic compound. This additive can improve the compatibility between linear carbonate and hard carbon anode material, enabling additive A to form an interface film with low impedance and high ionic conductivity on the positive and negative electrodes, thereby improving the high-temperature performance of sodium-ion batteries.

[0012] However, adding additive A alone has limited effect on improving the high-temperature cycle performance of sodium-ion batteries and cannot solve the high-temperature resistance problem of existing sodium-ion batteries. Research has found that when a phenylboronoxane heterocyclic compound is further added to additive A, it forms a dense and thin interfacial film on the positive and negative electrode materials. Simultaneously, the SEI and CEI films formed after the decomposition of this compound can suppress HF generation in the electrolyte, reduce the loss of active materials in the positive and negative electrode materials, and further stabilize the crystal structure of the positive and negative electrode materials, thereby improving the high-temperature performance of the battery. The synergistic effect of the two functional additives helps to form a sulfur-containing and aromatic ring-containing interfacial film with low impedance and high ionic conductivity, significantly improving the high-temperature cycle performance and storage performance of the battery.

[0013] The use of additive A, a phosphorus-oxygen heterocyclic compound, can reduce and decompose on the negative electrode surface to generate inorganic phases containing Na3PO4 and NaF, forming a rigid framework. Simultaneously, phosphorus-based compounds preferentially oxidize on the high-voltage positive electrode surface to form phosphorus-containing protective layers such as Na2PO3 and Na2P2O7, blocking direct contact between the electrolyte and the active material. Meanwhile, phenylboron-oxygen heterocyclic compound B generates flexible inorganic layers such as B2O3 and BN through BO bond cleavage. The two compounds intertwine to form a rigid-flexible composite SEI film. The phenylboron-oxygen heterocyclic compound is adsorbed onto the surface of the positive electrode particles through π-π conjugation, decomposing to generate boron-rich species such as LiBO2 and BOF, forming a gradient-distributed CEI film. The combined use of these two additives can suppress the structural collapse of the positive electrode material and the dissolution of transition metals, improving the high-temperature cycle stability of the battery. Therefore, the combined use of phosphorus-oxygen heterocyclic compound A and phenylboron-oxygen heterocyclic compound B can improve the cycle life of sodium-ion batteries under high-temperature conditions.

[0014] Preferably, additive A is any one or a combination of at least two of the following compounds;

[0015] .

[0016] Preferably, additive B is any one or a combination of at least two of the following compounds:

[0017] ;

[0018] Compound 6;

[0019] Compound 7;

[0020] Compound 8.

[0021] Preferably, the content of additive A is 0.5% to 5% based on the total mass of the electrolyte, for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5%.

[0022] Preferably, the content of additive B is 0.1%-4% based on the total mass of the electrolyte, for example 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.4%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 3% or 4%, preferably 0.5-3%.

[0023] Preferably, the additive also includes other additives.

[0024] Preferably, the other additives include sodium salt additives.

[0025] Preferably, the sodium salt additive includes any one or a combination of at least two of NaBOB (bis(oxalato)borate), NaFSi (sodium difluorosulfonate), NaODFB (sodium difluorooxalatoborate), and NaBF4 (sodium tetrafluoroborate).

[0026] Preferably, the sodium salt additive has a mass percentage content of 0.1% to 4%, for example, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5% or 4%, based on the total mass of the non-aqueous electrolyte as 100%.

[0027] Preferably, the additive further includes a film-forming additive.

[0028] Preferably, the film-forming additive is any one or a combination of at least two of the following: vinylene carbonate (VC), 1,3-propanesulfonate lactone (PS), fluoroethylene carbonate (FEC), ethylene ethylene sulfate (ES), ethylene sulfate (DTD), methane disulfonate (MMDS), ethylene vinylene carbonate (VEC), tri(trimethylsilane) phosphate (TMSP), and tri(trimethylsilane) borate (TMSB).

[0029] Preferably, the mass percentage of the film-forming additive is 0.5% to 11%, for example, 0.5%, 1.2%, 3.8%, 5.9%, 8.2%, 9.0%, 9.5%, 10%, 10.5% or 11%, based on the mass of the non-aqueous electrolyte as 100%.

[0030] Preferably, the electrolyte is a sodium salt, and the sodium salt is preferably NaPF6.

[0031] Preferably, the mass percentage of the electrolyte is 2-22%, based on the mass of the non-aqueous electrolyte as 100%, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 12%, 14%, 16%, 18%, 20%, or 22%.

[0032] Preferably, the non-aqueous organic solvent includes carbonate organic solvents.

[0033] Preferably, the carbonate organic solvent includes cyclic carbonates and / or chain carbonates.

[0034] Preferably, the cyclic carbonate includes any one or a combination of at least two of ethylene carbonate, propylene carbonate, or butene carbonate.

[0035] Preferably, the chain carbonate includes any one or a combination of at least two of diethyl carbonate, methyl ethyl carbonate, dimethyl carbonate, or methyl propyl carbonate.

[0036] Preferably, based on the mass of the non-aqueous electrolyte as 100%, the mass percentage of the non-aqueous organic solvent is 75% to 94%, for example 76%, 81%, 82%, 86%, 90%, 91% or 94%.

[0037] Preferably, the non-aqueous electrolyte further includes a stabilizer.

[0038] Preferably, the mass percentage of the stabilizer is 0.2-2.6% based on 100% of the mass of the non-aqueous electrolyte, for example, 0.2%, 0.5%, 1.0%, 1.1%, 1.6%, 2.2%, 2.5% or 2.6%.

[0039] In a second aspect, the present invention provides a sodium-ion battery, the sodium-ion battery comprising a positive electrode, a negative electrode, a separator, and an electrolyte, the electrolyte comprising the non-aqueous electrolyte as described in the first aspect.

[0040] Preferably, the positive electrode comprises a positive electrode active material, a conductive agent, and a binder, wherein the positive electrode active material comprises one of a sodium-containing layered oxide, a sodium-containing polyanionic compound, and a sodium-containing Prussian blue compound.

[0041] Preferably, the sodium-containing layered oxide includes a layered transition metal oxide, and the layered transition metal oxide includes a compound represented by the following formula I: Na x M y O z Formula I, where 0 < x ≤ 1, 0 < y ≤ 1, 1 < z ≤ 2, and M is selected from at least one of Cr, Fe, Co, Ni, Cu, Mn, Sn, Mo, Sb, and V;

[0042] Preferably, the Prussian blue compound includes a compound represented by formula II: Na x' L y' [L'(CN)6] y' ·z'H2O Formula II, where 0 < x' ≤ 1, 0 < y' ≤ 1, 1 < z' ≤ 2, and L and L' are selected from at least one of Cr, Fe, Co, Ni, Cu, Mn, Sn, Mo, Sb, and V.

[0043] Preferably, the polyanion compound includes at least one of phosphate compounds and sulfate compounds.

[0044] Preferably, the phosphate compound includes at least one of the compounds represented by formula III or formula IV: Na3(M'O 1-q PO4)2F 1+2q Formula III, where 0 < q ≤ 1, and M' is selected from at least one of Al, V, Ge, Fe, and Ga; Na2EPO4F Formula IV, where E is selected from at least one of Fe and Mn;

[0045] Preferably, the sulfate compound includes at least one of the compounds represented by formula V; Na2Y(SO4)2·2H2O Formula V, where Y is selected from at least one of Cr, Fe, Co, Ni, Cu, Mn, Sn, Mo, Sb, and V.

[0046] Preferably, the negative electrode sheet includes a negative electrode active material, and the negative electrode active material is selected from at least one of soft carbon, hard carbon, carbon nanotubes, expanded graphite, and graphene.

[0047] Preferably, the material of the separator includes one of polyethylene, polypropylene, or a composite ceramic membrane.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] The non-aqueous electrolyte provided by the present invention simultaneously adds additive A and phenylboroxine compound additive B. These two compounds act synergistically to improve the wide-temperature performance of the electrolyte, inhibit the dissolution of transition metal ions in the positive electrode material, improve its cycling performance at high and low temperatures, and can meet the application requirements of sodium-ion batteries. Detailed Implementation

[0050] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0051] Information on some of the raw materials used in the following examples and comparative examples is as follows:

[0052] Compound 1: CAS: 15171-48-9;

[0053] Compound 2: CAS: 20490-85-1;

[0054] Compound 3: CAS: 14651-62-8;

[0055] Compound 4: CAS: 448-59-9;

[0056] Compound 5: CAS: 5084-80-0;

[0057] Compound 6: CAS: 3262-89-3;

[0058] Compound 7: CAS: 223440-94-6;

[0059] Compound 8: CAS: 7187-84-0.

[0060] Examples 1-13 and Comparative Examples 1-4

[0061] A non-aqueous electrolyte is provided, the composition of which is shown in Tables 1 and 2.

[0062] Table 1

[0063]

[0064] Table 2

[0065]

[0066] Application Example 1-13 and Comparative Application Example 1-4

[0067] In Application Examples 1-13 and Comparative Application Examples 1-4, a secondary sodium-ion battery is provided. The sodium-ion battery includes a positive electrode, a negative electrode, a separator, and an electrolyte. The electrolyte is provided in Examples 1-10 and Comparative Examples 1-4, respectively.

[0068] The preparation method of sodium-ion batteries includes the following steps:

[0069] (1) Preparation of the positive electrode: Sodium nickel iron manganese oxide material, polyvinylidene fluoride (PVDF) binder, and Super P (SP) conductive agent were dispersed in N-methylpyrrolidone at a mass ratio of 93.5:1.5:5. After thorough stirring and uniform mixing (the solid content of the positive electrode slurry was 61.5%), it was coated on the current collector Al foil. The areal density of the positive electrode material was 33 mg / cm³. 2 After drying and rolling, the positive electrode sheet is obtained.

[0070] (2) Preparation of negative electrode sheet: The negative electrode active material hard carbon, thickener sodium carboxymethyl cellulose (CMC), binder styrene-butadiene rubber (SBR) and conductive agent SuperP (SP) are dispersed in deionized water at a mass ratio of 95:1.5:3:1.5. After thorough stirring and uniform mixing (the solid content of the negative electrode slurry is 55%), it is coated on the current collector Al foil. The areal density of the negative electrode material is 20.1 mg / cm³. 2 After drying and rolling, the negative electrode sheet is obtained.

[0071] (3) Preparation of electrolyte: Prepare electrolyte in a Mikelona glove box (filled with argon gas, with less than 10 ppm of gaseous water). First, mix organic solvents such as ethylene carbonate (EC), diethyl carbonate (EMC), methyl ethyl carbonate (DMC), and propylene carbonate (PC) in proportion (see Table 1 and Table 2 for specific proportions). Add general film-forming additives, additive A, and additive B to the mixed solvent package in sequence. Finally, add sodium salts such as NaPF6 and NaFSI. Mix until there is no sodium salt residue at the bottom and the electrolyte is clear and turbid. The electrolyte with normal color is obtained and stored in a -10℃ refrigerator. The proportions of each group are shown in Table 1 and Table 2.

[0072] (4) Cell manufacturing: The slit positive and negative electrode sheets are stacked on a stacking machine, and the separator is made of three layers of PP / PE / PP material to form a soft-pack cell.

[0073] (5) Liquid injection, formation and aging:

[0074] After the battery cells are dried at high temperature, the electrolytes from the examples and comparative examples are injected into the pouch cells. After electrolyte injection, the batteries undergo initial packaging and surface cleaning to complete the preliminary work, and are then left at room temperature for one day. Formation is performed using a step-by-step method: the first step uses a formation current of 0.05C, constant current charging for 2 hours; the second step uses a formation current of 0.1C, constant current charging until the voltage reaches 3.65V. After formation, the batteries undergo an aging treatment at 50°C for one day, and are then cooled to room temperature for final sealing.

[0075] <Battery Performance Test>

[0076] After the battery is assembled, it is left at room temperature for 10 hours to allow the electrolyte to fully wet the battery electrodes before being tested as follows.

[0077] ①25℃ ambient temperature cycle test: Constant current charge and discharge is performed in a 25℃ constant temperature chamber at a current density of 1C at the rated capacity. The cycle number is 1000. The test voltage range is 2V-4.0V. The charging cut-off current is 0.05C. After the test, the capacity retention rate of the 1000th cycle is calculated based on the discharge capacity of the first cycle.

[0078] The formula for calculating capacity retention after 1000 cycles at ambient temperature is as follows:

[0079] Capacity retention rate after 1000 cycles (%) = (Discharge capacity after 1000 cycles at room temperature / Initial discharge capacity) × 100%.

[0080] ② 45℃ High Temperature Cyclic Test: Constant current charge and discharge is performed in a 45℃ forced-air oven at a current density of 1C with the rated capacity. The cycle number is 800. The test voltage range is 2V-4.0V. The charging cut-off current is 0.05C. After the test, the capacity retention rate of the 800th cycle is calculated based on the discharge capacity of the first cycle.

[0081] The formula for calculating the capacity retention rate after 800-cycle high temperature cycling is as follows:

[0082] Capacity retention rate after 800 cycles (%) = (Discharge capacity after 800 high-temperature cycles / Initial discharge capacity) × 100%.

[0083] ③ High-Temperature Gas Generation Performance Test of Sodium-Ion Batteries: The batteries were subjected to constant current charging and discharging at 1C current density with rated capacity in a 25℃ constant temperature chamber, followed by constant voltage charging at 4.0V until the current reached 0.05C. After full charging, the initial volume of the battery was tested using the water displacement method. The batteries were then stored in a 60℃ oven for 7 days, and then removed. They were allowed to stand at room temperature for 60 minutes. After cooling to room temperature, the battery volume was tested using the water displacement method.

[0084] Perform storage tests following the steps outlined above, up to 28 days. Using the battery volume tested before storage as a baseline, calculate the battery's volume expansion rate over storage time.

[0085] High-temperature storage volume expansion rate on day 28 = (Volume after high-temperature storage on day 28 - Initial battery volume / Initial battery volume) × 100%.

[0086] The test results of the examples and comparative examples are shown in Tables 3 and 4, respectively.

[0087] Table 3

[0088]

[0089] Table 4

[0090]

[0091] Analysis of the data in Tables 3 and 4 shows that the electrolyte of this invention, by adding additive A (phosphorus oxide heterocyclic compound) and additive B (phenyl boron oxide heterocyclic compound), enables the secondary sodium-ion battery to have good capacity retention at room temperature and high capacity retention at high temperature, and can greatly suppress the volume expansion of the battery during storage. As shown in Examples 1 to 13, the sodium-ion battery assembled with the electrolyte has a capacity retention rate of 82.9-89.9% under the test conditions of 25°C and 1C, a capacity retention rate of 82.1-87.4% under the test conditions of 45°C and 1C, and a volume expansion rate of 5.8-9.4% after storage at 60°C for 28 days.

[0092] Analysis of the examples and comparative examples shows that only when phosphorus oxide heterocyclic compound A and phenyl boron oxide heterocyclic compound B are used in combination and the usage conditions are met can the overall performance of the battery be significantly improved.

[0093] The applicant declares that this invention illustrates the non-aqueous electrolyte and sodium-ion battery through the above embodiments, but the invention is not limited to the above embodiments, that is, it does not mean that the invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials in the product of this invention, additions of auxiliary components, and selection of specific methods, all fall within the protection and disclosure scope of this invention.

Claims

1. A nonaqueous electrolyte solution for application to a sodium-ion battery, characterized by comprising: The non-aqueous electrolyte comprises an electrolyte, a non-aqueous organic solvent and an additive, the additive comprises an additive A and an additive B, the additive A is a phosphorus oxo compound shown in formula 1, and the additive B is a phenyl boron oxo compound shown in formula 2. ； Wherein, R1, R2, R3 and R4 are independently selected from hydrogen, substituted or unsubstituted C1-C3 alkyl, substituted or unsubstituted phenyl, substituted or unsubstituted phenoxy or substituted or unsubstituted biphenyl, and the substituted substituent is selected from a halogen atom or C1-C3 alkyl.

2. The nonaqueous electrolyte according to claim 1, characterized by The additive A is any one or a combination of at least two of the following compounds: 。 3. The nonaqueous electrolyte according to claim 1, characterized by The additive B is any one or a combination of at least two of the following compounds: ； ； 。 4. The nonaqueous electrolyte according to any one of claims 1 to 3, characterized by The content of the additive A is 0.5%-5% based on the total mass of the electrolyte being 100%; Preferably, the content of the additive B is 0.1%-4%, preferably 0.5-3%, based on the total mass of the electrolyte being 100%.

5. The nonaqueous electrolyte according to any one of claims 1 to 4, characterized by The additive further comprises other additives; Preferably, the other additives comprise sodium salt additives; Preferably, the sodium salt additives comprise any one or a combination of at least two of bisoxalate borate, sodium difluorosulfonimide, sodium difluoro oxalate borate or sodium tetrafluoroborate; Preferably, the mass percentage of the sodium salt additives is 0.1-4% based on the total mass of the non-aqueous electrolyte being 100%.

6. The nonaqueous electrolyte according to any one of claims 1 to 5, characterized by The additive further comprises a film-forming additive; Preferably, the film-forming additive is any one or a combination of at least two of vinylene carbonate, 1,3-propane sulfonic acid endolide, fluorinated ethylene carbonate, vinyl ethylene sulfate, vinyl sulfate, methane disulfonic acid methylene, vinyl ethylene carbonate, tris(trimethylsilyl)phosphate or tris(trimethylsilyl)borate; Preferably, the mass percentage of the film-forming additive is 0.5-11% based on the mass of the non-aqueous electrolyte being 100%.

7. The nonaqueous electrolyte according to any one of claims 1 to 6, characterized by The electrolyte is a sodium salt, and the sodium salt is preferably NaPF6; Preferably, the mass percentage of the electrolyte is 2-22% based on the mass of the non-aqueous electrolyte being 100%; Preferably, the non-aqueous organic solvent comprises a carbonate organic solvent; Preferably, the carbonate organic solvent comprises a cyclic carbonate and / or a chain carbonate; Preferably, the cyclic carbonate comprises any one or a combination of at least two of vinylene carbonate, propylene carbonate or butylene carbonate; Preferably, the chain carbonate comprises any one or a combination of at least two of diethyl carbonate, methyl ethyl carbonate, dimethyl carbonate or methyl propyl carbonate; Preferably, the mass percentage of the non-aqueous organic solvent is 75%-94% based on the mass of the non-aqueous electrolyte being 100%. Preferably, the non-aqueous electrolyte further comprises a stabilizer; Preferably, the mass percentage of the stabilizer is 0.2-2.6% based on the mass of the non-aqueous electrolyte being 100%.

8. A sodium-ion battery, characterized in that, The sodium ion battery comprises a positive electrode sheet, a negative electrode sheet, a separator and an electrolyte, and the electrolyte comprises the non-aqueous electrolyte according to any one of claims 1-7.

9. The sodium-ion battery of claim 8, wherein, The positive electrode comprises a positive electrode active material, a conductive agent, and a binder, and the active material of the positive electrode comprises one of a sodium-containing layered oxide, a sodium-containing polyanionic compound, and a sodium-containing Prussian blue compound; Preferably, the sodium-containing layered oxide comprises a layered transition metal oxide comprising a compound having the following formula I: Na x M y O z Formula I, wherein 0 < x < 1, 0 < y < 1, 1 < z < 2, M is selected from at least one of Cr, Fe, Co, Ni, Cu, Mn, Sn, Mo, Sb, V. Preferably, the Prussian blue compound comprises a compound according to Formula II: Na x' L y' [L' (CN)6] y' z' H2O Formula II, wherein 0 < x' < 1, 0 < y' < 1, 1 < z' < 2, L and L' are selected from at least one of Cr, Fe, Co, Ni, Cu, Mn, Sn, Mo, Sb, V. Preferably, the polyanionic compound comprises at least one of a phosphate compound and a sulfate compound; Preferably, the phosphate-based compound comprises at least one of the compounds of Formula III or Formula IV: Na3(M'0 1- q PO4)2F 1+2q Formula III, wherein 0 < q < 1, M' is selected from at least one of Al, V, Ge, Fe, Ga; Na2EPO4F Formula IV, wherein E is selected from at least one of Fe, Mn; Preferably, the sulfate compound comprises at least one of the compounds shown in Formula V: Na2Y(SO4)2·2H2O Formula V, wherein Y is selected from at least one of Cr, Fe, Co, Ni, Cu, Mn, Sn, Mo, Sb, or V.

10. The sodium-ion battery of claim 8, wherein, The negative electrode tab comprises a negative electrode active material selected from at least one of soft carbon, hard carbon, carbon nanotubes, expanded graphite, and graphene; Preferably, the material of the separator comprises one of polyethylene, polypropylene, or a composite ceramic membrane.

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