Zinc metaniobate negative electrode material and preparation method and application thereof

Abstract

The application relates to the technical field of lithium ion batteries, and particularly discloses a zinc metatitanate negative electrode material and a preparation method and application thereof, which comprises the following steps: S1, sodium stannate and zinc acetate and urea are dissolved in a mixed solution of ethanol and deionized water, and after uniform mixing, zinc metatitanate powder is obtained through hydrothermal treatment, centrifugal drying and calcination; S2, a lithiation reagent and metal lithium are dissolved in a tetrahydrofuran solvent to obtain a chemical prelithiation reagent solution, and the prelithiation reagent solution at least comprises diphenyl, lithium and tetrahydrofuran; S3, the prepared zinc metatitanate powder is reacted in the chemical prelithiation reagent solution or in the chemical prelithiation reagent vapor, and after vacuum drying, zinc metatitanate negative electrode material is collected. Through a prelithiation method, a uniform SEI film is generated on the surface of the zinc metatitanate material, the material surface can be effectively protected, and the occurrence of irreversible reactions can be reduced, so that the first-cycle coulombic efficiency and the cycle stability of the negative electrode material are improved, and the cycle performance can be improved.

Description

Technical Field

[0001] This invention belongs to the field of lithium-ion battery technology, specifically relating to a zinc metastannate anode material, its preparation method, and its application. Background Technology

[0002] With the increasing severity of environmental problems and the growing demand for energy, various electrochemical energy storage systems (EES) have emerged and developed rapidly. Rechargeable metal-ion batteries are considered one of the most promising electrochemical energy storage systems due to their high energy consumption and long battery life. Lithium-ion batteries (LIBs), with their superior advantages including high energy density, no memory effect, and low self-discharge, are the most representative rechargeable metal-ion batteries, widely used in portable electronic devices, electric vehicles, and grid energy storage. It is important to note that the electrochemical performance of these batteries primarily depends on the electrode materials. To meet market demands, there is a need to develop batteries with higher specific capacity (>600 mAh·g). -1 It is a negative electrode material with stable capacity and excellent rate performance.

[0003] Zinc metastannate (ZnSnO3) is a multifunctional ternary metal oxide material that has long been a popular functional material in chemistry and physics, used in applications such as lead-free ferroelectrics, transparent conductors, photocatalysts, dye-sensitized solar cells, and gas sensors. In recent years, its extremely high theoretical capacity (1317 mAh·g) has garnered significant attention. -1 With its lower operating potential, it is considered a highly promising anode candidate material for lithium-ion batteries. More importantly, as a bimetallic oxide, it also has greater inherent advantages than single-metallic zinc oxide (ZnO) and tin dioxide (SnO2), especially its tunable operating potential and higher electronic conductivity.

[0004] However, research on zinc stannate as a negative electrode material for lithium-ion batteries is currently limited. The main reason is the low coulombic efficiency of zinc stannate in the first cycle, leading to low battery energy efficiency. It also exhibits pulverization and agglomeration during cycling, resulting in poor battery performance. Therefore, developing a method for efficiently modifying zinc stannate is crucial for the development of lithium-ion battery negative electrode materials. Pre-lithiation technology involves adding a small amount of lithium source to the electrode material before the battery's formal charge-discharge cycle. This compensates for lithium loss caused by the formation of the solid electrolyte interface and side reactions during the first cycle, thereby improving the first-cycle coulombic efficiency and increasing reversible capacity. To date, previous researchers have conducted extensive research on pre-lithiation. A common pre-lithiation method for negative electrodes is direct lithium supplementation, such as lithium foil supplementation. While this method seems easy to implement, lithium ions are not evenly distributed on the anode, resulting in poor performance. An alternative method is electrochemical pre-lithiation, where lithium foil serves as the counter electrode to form a half-cell, achieving pre-lithiation through discharge or short circuit. This method allows for control over the degree of pre-lithiation, but the operations involved in assembling and disassembling half-cells make it more complex to implement. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned shortcomings of existing technologies by providing a zinc stannate anode material, its preparation method, and its applications. This is achieved by immersing the anode material in a pre-lithiation reagent followed by drying and collection. This process involves a redox reaction, resulting in the uniform embedding of lithium ions onto the anode. The pre-lithiation reagent typically consists of a strong reducing agent (such as lithium naphthylene (Li-Naph) and lithium biphenyl) and an ether solvent (such as tetrahydrofuran and dimethoxyethane), which forms a uniform protective film on the surface. This protective film effectively protects the electrode surface, reduces irreversible reactions, and thus improves the first-cycle coulombic efficiency and cycle stability of the anode material.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The first objective of this invention is to provide a method for preparing a zinc metastannate anode material, comprising the following steps:

[0008] S1: Dissolve an appropriate amount of sodium stannate, zinc acetate, and urea in a mixed solution of ethanol and deionized water. After uniform mixing, the solution is dried by hydrothermal heating, centrifugation, and calcination to obtain zinc metastannate powder.

[0009] S2: Dissolve the lithiation reagent and metallic lithium in tetrahydrofuran solvent to obtain a chemical prelithiation reagent solution, wherein the prelithiation reagent solution includes at least biphenyl, lithium, and tetrahydrofuran;

[0010] S3: The prepared zinc stannate powder is placed in a chemical pre-lithiation reagent solution for reaction or in a chemical pre-lithiation reagent vapor, and then vacuum dried to obtain the chemically pre-lithiated zinc stannate anode material.

[0011] Furthermore, in S1, the molar ratio of tin to zinc added to the drug is 1:1, and the volume ratio of ethanol to deionized water is 1:(1-3).

[0012] Furthermore, the mixing method in S1 is either stirring or ultrasonication, and the mixing time is 0.1 to 3 hours.

[0013] Furthermore, the hydrothermal conditions in S1 are a temperature of 150–180°C and a time of 4–6 hours;

[0014] Furthermore, the centrifugation conditions are a speed of 7200–7800 r / min and a time of 3–5 min. The drying treatment is any one of atmospheric pressure drying, vacuum drying, spray drying, microwave drying, and infrared drying, and the drying temperature is 40–120℃.

[0015] Furthermore, the calcination conditions are: temperature 450–650℃, heating rate 2–10℃ / min, calcination time 2–6h, and calcination atmosphere is any one of dry air, nitrogen, or argon. The product is then naturally cooled to room temperature.

[0016] Furthermore, in step S2, the pre-lithiation solvent includes at least one or more of tetrahydrofuran, ethylene glycol dimethyl ether, methyl propyl ether, methyl butyl ether, methyl pentyl ether, ethyl propyl ether, ethyl butyl ether, ethyl pentyl ether, propyl butyl ether, propyl pentyl ether, methyl tetrahydrofuran, dimethyl tetrahydrofuran, ethyl tetrahydrofuran, diethyl tetrahydrofuran, phenyl tetrahydrofuran, 1,2-dimethoxyethane, and diethylene glycol dimethyl ether.

[0017] Furthermore, in step S2, the lithium-ionizing agent includes at least one or more of the following: biphenyl, naphthalene, methylnaphthalene, dimethylnaphthalene, tetramethylnaphthalene, anthracene, methylanthracene, dimethylanthracene, tetramethylphenanthrene, phenanthrene, methylphenanthrene, dimethylphenanthrene, trimethylphenanthrene, tetramethylphenanthrene, pyrene, methylpyrene, dimethylpyrene, trimethylpyrene, tetramethylpyrene, methylpyrene, dimethylpyrene, trimethylpyrene, tetramethylpyrene, methylpyrene, dimethylpyrene, trimethylpyrene, tetramethylpyrene, methylbiphenyl, dimethylbiphenyl, and tetramethylbiphenyl.

[0018] Furthermore, in step S2, the lithium metal includes at least one or more of lithium sheets and lithium strips.

[0019] Furthermore, in step S3, the reaction time in the chemical pre-lithiation reagent solution is 5–60 min.

[0020] Furthermore, in step S3, the concentration of the pre-lithiation reagent is 1 mol / L, 1.5 mol / L, or 0.5 mol / L.

[0021] Furthermore, in step S3, pre-lithiation vapor is introduced into the vapor chamber, and the zinc stannate negative electrode sheet passes through and is exposed to the vapor chamber for 20 minutes.

[0022] Furthermore, in step S3, the liquid pre-lithiation reagent is heated, and a carrier gas is introduced to form pre-lithiation vapor, the temperature of which is between the boiling point of the pre-lithiation reagent and ±40°C.

[0023] Furthermore, in step S3, the zinc stannate negative electrode sheet includes at least the following components: 50-99 wt% zinc stannate negative electrode material, 0.5-40 wt% conductive agent, and 0.5-10 wt% binder.

[0024] Furthermore, in step S3, the conductive agent includes at least one or more of acetylene black, Ketjen black, Super P, MCMB, and carbon nanotubes.

[0025] Furthermore, in step S3, the adhesive includes at least one or more of the following: polyvinylidene fluoride, polyvinyl chloride, polyvinyl butyral, polyacrylonitrile, polyacrylic acid, polyethylene glycol, polypyrrole, polyaniline, sucrose, glucose, maltose, citric acid, asphalt, furfural resin, epoxy resin, phenolic resin, sodium alginate, and carboxymethyl cellulose.

[0026] The second objective of this invention is to provide a zinc stannate anode material prepared by the above-described method.

[0027] The third objective of this invention is to provide a zinc stannate negative electrode sheet, which is obtained by fully mixing the above-mentioned zinc stannate material, binder, and conductive carbon in a certain proportion, coating it onto copper foil material, and then drying and cutting it.

[0028] Furthermore, the zinc stannate negative electrode sheet comprises at least the following components: 50–99 wt% zinc stannate negative electrode material, 0.5–40 wt% conductive agent, and 0.5–10 wt% binder. The conductive agent comprises at least one or more of acetylene black, Ketjen black, Super P, MCMB, and carbon nanotubes. The binder comprises at least one or more of polyvinylidene fluoride, polyvinyl chloride, polyvinyl butyral, polyacrylonitrile, polyacrylic acid, polyethylene glycol, polypyrrole, polyaniline, sucrose, glucose, maltose, citric acid, asphalt, furfural resin, epoxy resin, phenolic resin, sodium alginate, and carboxymethyl cellulose.

[0029] A fourth objective of the present invention is to provide an electrode comprising the aforementioned zinc stannate negative electrode sheet.

[0030] A fifth objective of the present invention is to provide a lithium-ion secondary battery comprising the electrodes described above.

[0031] Compared with the prior art, the beneficial effects of the technical solution provided by the present invention are as follows:

[0032] This invention proposes a method for preparing zinc stannate anode material. It utilizes the relative stability of a pre-lithiation reagent made from biphenyl-lithium-tetrahydrofuran in ambient air and the unique electrochemical behavior of biphenyl in ether and carbonate solvents. In ether solvents (e.g., tetrahydrofuran and dimethoxyethane), it can react with lithium metal to form a strong reducing agent, Li-Bp (biphenyl-lithium). Furthermore, the obtained pre-lithiation reagent is relatively less affected by air and moisture. The pre-lithiation method generates a uniform SEI film on the surface of the zinc stannate material, effectively protecting the material surface and reducing irreversible reactions. This improves the first-cycle coulombic efficiency and cycle stability of the anode material, thus enhancing cycle performance. In addition, the pre-lithiation method allows lithium ions to successfully embed into the anode, controllably and uniformly compensating for irreversible lithium loss to achieve a higher first-cycle coulombic efficiency, thereby effectively modifying battery performance. Attached Figure Description

[0033] Figure 1a and Figure 1b Images of zinc stannate at different magnifications under a scanning electron microscope (SEM);

[0034] Figure 2 XRD comparison diagrams of zinc metastannate and its precursor ZnSn(OH)6;

[0035] Figure 3 This is a schematic diagram of the first three charge-discharge cycles of untreated zinc stannate material in the voltage range of 0.01V-3V.

[0036] Figure 4 This is a schematic diagram of the first three charge-discharge cycles of zinc stannate material after pre-lithiation in Example 1 within a voltage range of 0.01V-3V.

[0037] Figure 5 A schematic diagram of the first-cycle coulombic efficiency of batteries assembled with zinc stannate anode material in different embodiments;

[0038] Figure 6 A comparison of XPS spectra before and after pre-lithiation in Example 1;

[0039] Figure 7 This is a cross-sectional view of the untreated zinc metastannate negative electrode sheet;

[0040] Figure 8 This is an interface diagram of the zinc stannate negative electrode after steam pre-lithiation treatment. Detailed Implementation

[0041] To make the present invention easier to understand, specific embodiments are described below to further illustrate the invention. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical terms used below have the same meaning as understood by those skilled in the art; unless otherwise specified, the raw materials and reagents involved in the present invention can be purchased from the market or obtained by known methods.

[0042] The zinc metastannate electrode preparation process used in the examples is as follows:

[0043] Material preparation: 0.425 g of sodium stannate and 0.367 g of anhydrous zinc acetate were dissolved in two beakers containing 15 ml of ethanol and 15 ml of deionized water, respectively, with a volume ratio of ethanol to deionized water of 1:1. After stirring for 5 h, the two solutions were mixed, and then 3.5 g of urea was added. After stirring for another 3 h, the mixed solution was poured into a 50 ml reactor for hydrothermal reaction at 170 °C for 5 h. Then, the mixture was centrifuged multiple times using ethanol and deionized water at 7500 r / min. Subsequently, it was vacuum dried at 90 °C. The dried powder was then calcined in dry air at 400 °C at a rate of 5 °C / min for 3 h. After natural cooling, zinc metastannate powder material was obtained.

[0044] Pre-lithiation step: Under an inert atmosphere, an appropriate amount of zinc stannate material is placed in a 1M chemical pre-lithiation solution and reacted for 5 to 60 minutes. After the reaction is complete, the material is vacuum dried and collected to obtain the pre-lithiated zinc stannate material.

[0045] Electrode preparation: Zinc stannate powder (or pre-lithiated zinc stannate powder), conductive carbon black (Super P), and binder (PVDF) were weighed and mixed in a weight ratio of 7:2:1. Dimethylpyrrolidone (NMP) was added as a solvent, and the mixture was stirred to form a homogeneous slurry. The slurry was evenly coated onto copper foil and dried at 80℃ for 12 hours. The electrode sheets were then cut into 12mm diameter discs, with each disc having an active material loading of approximately 1-3 mg / cm³. 2 This disc is the required zinc metastannate negative electrode.

[0046] Battery assembly: Using LiPF6 added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), lithium metal was used as the negative electrode, a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0047] Battery electrical performance testing: The assembled battery was tested using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The anode film loading density was approximately 1 mg / cm³. -2 ~3mg cm -2 The specific capacity is calculated based on the amount of lithium metal oxide component in the anode film (i.e., the weight after removing the weight of conductive carbon black, binder, and carbon coating). The test conditions are as follows: the charge and discharge voltage range is 0.01V to 3V, and constant current charge and discharge tests are performed at a current density of 0.5C or 1C.

[0048] X-ray diffraction (XRD) testing: A Bruker D8 Focus X-ray powder diffractometer (Japan / Germany) was used, with Cu-Kα as the radiation source and a wavelength of 1.5046λ. A Ni filter was used, with a tube current of 40 mA, a tube voltage of 40 kV, a scanning range of 20°–80°, a scanning speed of 5° / min, and a step size of 0.05°. The material was flattened in a glass slide and embedded in the center of the instrument's experimental slot for testing. Phase identification and crystal structure information were analyzed using JADE 6.0 software.

[0049] Example 1

[0050] Preparation of pre-lithiation reagent: To prepare a 1M biphenyl-lithium-tetrahydrofuran solution, first weigh 0.77g of biphenyl and dissolve it in 5ml of tetrahydrofuran solution. Then, dissolve 0.035g of lithium in the mixed solution of biphenyl and tetrahydrofuran until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0051] The prepared zinc stannate material (denoted as A0) was placed in a 1M pre-lithiation reagent in a glove box and reacted for 20 minutes. The pre-lithiation reagent was composed of a solvent tetrahydrofuran, a solute lithium sheet, and biphenyl. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A1) was collected by vacuum drying.

[0052] Electrode preparation: The pre-lithiated zinc stannate anode material (A1), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0053] Battery assembly: LiPF6 was added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0054] Electrochemical performance testing:

[0055] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 .

[0056] The results are shown in Table 1:

[0057] Table 1. Comparison of battery performance between A0 and A1

[0058]

[0059] As shown in Table 1, the first-cycle coulombic efficiency was improved by 38.95% after pre-lithiation using a biphenyl-lithium-tetrahydrofuran solution, and the capacity retention after 100 cycles also increased from 19.93% to 71.52%. Figure 3 and Figure 4 It can be seen that the original sample no longer provides capacity above 1.5V, resulting in very low efficiency in the first cycle, while the charge-discharge curve after pre-lithiation has a better plateau, with an initial efficiency of up to 94.38%. Figure 5 The XPS comparison images are of zinc stannate material before and after treatment with biphenyl-lithium-tetrahydrofuran pre-lithiation solution for 20 minutes. It can be seen that no lithium peak was detected in the untreated zinc stannate material, while a lithium peak was clearly detected after treatment in the example. This suggests that lithium ions were successfully intercalated.

[0060] Example 2

[0061] Preparation of pre-lithiation reagent: Prepare a 1M biphenyl-lithium-ethylene glycol dimethyl ether solution. First, weigh 0.77g of biphenyl and dissolve it in 5ml of ethylene glycol dimethyl ether solution. Then, dissolve 0.035g of lithium in the mixed solution of biphenyl and ethylene glycol dimethyl ether until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0062] The prepared zinc stannate material (denoted as A0) was placed in a 1M pre-lithiation reagent in a glove box and reacted for 20 minutes. The pre-lithiation reagent was composed of a solvent of ethylene glycol dimethyl ether, a solute of lithium flakes, and biphenyl. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A2) was collected by vacuum drying.

[0063] Electrode preparation: The pre-lithiated zinc stannate anode material (A2), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0064] Battery assembly: LiPF6 was added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0065] Electrochemical performance testing:

[0066] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 .

[0067] The results are shown in Table 2:

[0068] Table 2. Comparison of battery performance between A0 and A2.

[0069]

[0070] As can be seen from Table 2, the first-cycle coulombic efficiency was improved by 29.8% after pre-lithiation with biphenyl-lithium-ethylene glycol dimethyl ether solution, proving that the SEI film generated on the electrode surface by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 60.65%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1.

[0071] Example 3

[0072] Preparation of pre-lithiation reagent: To prepare a 1M naphthalene-lithium-tetrahydrofuran solution, first weigh 0.64g of naphthalene and dissolve it in 5ml of tetrahydrofuran solution. Then, dissolve 0.035g of lithium in the mixed solution of naphthalene and tetrahydrofuran until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0073] The prepared zinc stannate material (denoted as A0) was placed in a glove box and reacted for 5 minutes in a pre-lithiation reagent, which was composed of a solvent tetrahydrofuran, a solute lithium sheet, and naphthalene. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A3) was collected by vacuum drying.

[0074] Electrode preparation: The pre-lithiated zinc stannate anode material (A3), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0075] Battery assembly: LiPF6 was added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0076] Electrochemical performance testing:

[0077] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 .

[0078] The results are shown in Table 3:

[0079] Table 3. Comparison of battery performance between A0 and A3

[0080]

[0081] As can be seen from Table 3, the first-cycle coulombic efficiency was improved by 27.62% after pre-lithiation with naphthalene-lithium-tetrahydrofuran solution, proving that the SEI film generated on the electrode surface by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 61.38%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1.

[0082] Example 4

[0083] Preparation of pre-lithiation reagent: Prepare a 1M naphthalene-lithium-ethylene glycol dimethyl ether solution. First, weigh 0.64g of naphthalene and dissolve it in 5ml of ethylene glycol dimethyl ether solution. Then, dissolve 0.035g of lithium flakes in the mixed solution of naphthalene and ethylene glycol dimethyl ether until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0084] The prepared zinc stannate material (denoted as A0) was placed in a glove box and reacted in a pre-lithiation reagent for 60 minutes. The pre-lithiation reagent was composed of a solvent of ethylene glycol dimethyl ether, a solute of lithium flakes and naphthalene. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A4) was obtained by vacuum drying and collection.

[0085] Electrode preparation: The pre-lithiated zinc stannate anode material (A4), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0086] Battery Assembly: CR2032 button cells were assembled using LiPF6 added to a ethylene carbonate (EC) and dimethyl carbonate (DMC) solution (volume ratio 1:1), with lithium metal as the negative electrode, a glass fiber membrane (GE Whatman) as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) as the electrolyte, in an argon-filled glove box. Electrochemical Performance Testing:

[0087] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 .

[0088] The results are shown in Table 4:

[0089] Table 4. Comparison of battery performance between A0 and A4

[0090]

[0091] As can be seen from Table 4, the first-cycle coulombic efficiency was improved by 19.21% after pre-lithiation with naphthalene-lithium-ethylene glycol dimethyl ether solution, proving that the SEI film generated on the electrode surface by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 59.12%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1.

[0092] To investigate the effect of the ratio of prelithiation reagents on the electrochemical performance of zinc stannate anode materials, the following experiments will continue with changes to the ratios of the prelithiation reagents (biphenyl / lithium sheet / tetrahydrofuran) in Example 1 and (biphenyl / lithium sheet / ethylene glycol dimethyl ether) in Example 2.

[0093] Example 5

[0094] Preparation of pre-lithiation reagent: Prepare a 1.5M biphenyl-lithium-tetrahydrofuran solution. First, weigh 1.16g of biphenyl and dissolve it in 5ml of tetrahydrofuran solution. Then, dissolve 0.052g of lithium in the mixed solution of biphenyl and tetrahydrofuran until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0095] The prepared zinc stannate material (denoted as A0) was placed in a glove box and reacted in a pre-lithiation reagent for 20 minutes. The pre-lithiation reagent was composed of a solvent tetrahydrofuran, a solute lithium sheet, and biphenyl. After the reaction was completed, the pre-lithiated zinc stannate electrode (denoted as A5) was collected by vacuum drying.

[0096] Electrode preparation: The pre-lithiated zinc stannate anode material (A5), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0097] Battery Assembly: CR2032 button cells were assembled using LiPF6 added to a ethylene carbonate (EC) and dimethyl carbonate (DMC) solution (volume ratio 1:1), with lithium metal as the negative electrode, a glass fiber membrane (GE Whatman) as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) as the electrolyte, in an argon-filled glove box. Electrochemical Performance Testing:

[0098] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 The results are shown in Table 5:

[0099] Table 5. Comparison of battery performance between A0 and A5

[0100]

[0101] As can be seen from Table 5, the first-cycle coulombic efficiency was improved by 35.24% after pre-lithiation with biphenyl-lithium-tetrahydrofuran solution, proving that the SEI film generated on the electrode surface by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 70.03%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1.

[0102] Example 6

[0103] Preparation of pre-lithiation reagent: Prepare a 0.5M biphenyl-lithium-tetrahydrofuran solution. First, weigh 0.39g of biphenyl and dissolve it in 5ml of tetrahydrofuran solution. Then, dissolve 0.017g of lithium in the mixed solution of biphenyl and tetrahydrofuran until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0104] The prepared zinc stannate material (denoted as A0) was placed in a glove box and reacted in a pre-lithiation reagent for 20 minutes. The pre-lithiation reagent was composed of a solvent tetrahydrofuran, a solute lithium sheet, and biphenyl. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A6) was collected by vacuum drying.

[0105] Electrode preparation: The pre-lithiated zinc stannate anode material (A6), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0106] Battery Assembly: CR2032 button cells were assembled using LiPF6 added to a ethylene carbonate (EC) and dimethyl carbonate (DMC) solution (volume ratio 1:1), with lithium metal as the negative electrode, a glass fiber membrane (GE Whatman) as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) as the electrolyte, in an argon-filled glove box. Electrochemical Performance Testing:

[0107] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 The results are shown in Table 6:

[0108] Table 6. Comparison of Battery Performance between A0 and A6

[0109]

[0110] As can be seen from Table 6, the first-cycle coulombic efficiency was improved by 32.37% after pre-lithiation with biphenyl-lithium-tetrahydrofuran solution, proving that the SEI film generated on the electrode surface by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 66.5%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1.

[0111] Example 7

[0112] Preparation of pre-lithiation reagent: Prepare a 1.5M biphenyl-lithium-ethylene glycol dimethyl ether solution. First, weigh 1.16g of biphenyl and dissolve it in 5ml of ethylene glycol dimethyl ether solution. Then, dissolve 0.052g of lithium in the mixed solution of biphenyl and ethylene glycol dimethyl ether until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0113] The prepared zinc stannate material (denoted as A0) was placed in a glove box and reacted in a pre-lithiation reagent for 20 minutes. The pre-lithiation reagent was composed of a solvent of ethylene glycol dimethyl ether, a solute of lithium flakes, and biphenyl. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A7) was collected by vacuum drying.

[0114] Electrode preparation: The pre-lithiated zinc stannate anode material (A7), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0115] Battery Assembly: CR2032 button cells were assembled using LiPF6 added to a ethylene carbonate (EC) and dimethyl carbonate (DMC) solution (volume ratio 1:1), with lithium metal as the negative electrode, a glass fiber membrane (GE Whatman) as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) as the electrolyte, in an argon-filled glove box. Electrochemical Performance Testing:

[0116] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 The results are shown in Table 7:

[0117] Table 7. Comparison of Battery Performance between A0 and A7

[0118]

[0119] As can be seen from Table 7, the first-cycle coulombic efficiency was improved by 24.16% after pre-lithiation with biphenyl-lithium-tetrahydrofuran solution, proving that the SEI film generated on the surface of zinc stannate material by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 58.59%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 2 and Example 1.

[0120] Example 8

[0121] Preparation of pre-lithiation reagent: Prepare a 0.5M biphenyl-lithium-ethylene glycol dimethyl ether solution. First, weigh 0.39g of biphenyl and dissolve it in 5ml of ethylene glycol dimethyl ether solution. Then, dissolve 0.017g of lithium in the mixed solution of biphenyl and ethylene glycol dimethyl ether until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0122] The prepared zinc stannate material (denoted as A0) was placed in a glove box and reacted in a pre-lithiation reagent for 20 minutes. The pre-lithiation reagent was composed of a solvent of ethylene glycol dimethyl ether, a solute of lithium flakes, and biphenyl. After the reaction was completed, the pre-lithiated zinc stannate anode material (denoted as A8) was obtained by vacuum drying.

[0123] Electrode preparation: The pre-lithiated zinc stannate anode material (A8), binder, and conductive carbon are thoroughly mixed in a ratio of 7:2:1, and then coated onto copper foil material. After drying and cutting, zinc stannate anode electrode sheets are obtained.

[0124] Battery Assembly: CR2032 button cells were assembled using LiPF6 added to a ethylene carbonate (EC) and dimethyl carbonate (DMC) solution (volume ratio 1:1), with lithium metal as the negative electrode, a glass fiber membrane (GE Whatman) as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) as the electrolyte, in an argon-filled glove box. Electrochemical Performance Testing:

[0125] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 The results are shown in Table 8:

[0126] Table 8. Comparison of battery performance between A0 and A8

[0127]

[0128] As shown in Table 8, the first-cycle coulombic efficiency was improved by 5.3% after pre-lithiation with 0.5M biphenyl-lithium-ethylene glycol dimethyl ether solution, proving that the SEI film generated on the surface of zinc stannate material by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 39.22%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 2 and Example 1.

[0129] Depend on Figure 5As can be seen from the above embodiments, different pre-lithiation reagents all have a modifying effect on zinc stannate anode materials, among which the pre-lithiation reagent with a 1M ratio of lithium-biphenyl-tetrahydrofuran has the best effect.

[0130] To further investigate the pre-lithiation effect of chemical pre-lithiation reagents on zinc stannate materials, pre-lithiation reagents of different concentrations were used to form pre-lithiation vapor in gaseous form. The original zinc stannate negative electrode was then placed in the vapor, allowing the pre-lithiation vapor to diffuse onto the negative electrode, resulting in a vapor-prelithiated zinc stannate electrode.

[0131] Example 9

[0132] Preparation of pre-lithiation reagent: To prepare a 1M biphenyl-lithium-tetrahydrofuran solution, first weigh 0.77g of biphenyl and dissolve it in 5ml of tetrahydrofuran solution. Then, dissolve 0.035g of lithium in the mixed solution of biphenyl and tetrahydrofuran until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0133] Electrode preparation: The zinc metastannate anode material, binder, and conductive carbon without any treatment are thoroughly mixed in a ratio of 7:2:1, and then coated on copper foil material. After drying and cutting, the zinc metastannate anode sheet is obtained.

[0134] Nitrogen gas is heated to 80°C and then passed into an acetonitrile tank. The nitrogen and acetonitrile mixture is introduced into the steam chamber through the inlet, with the gas flow rate controlled at 80 mL / min. The gas is then recycled through the outlet. The prepared zinc stannate anode sheet (denoted as A0) is placed in a 1M pre-lithiation reagent vapor and reacted for 20 minutes. This pre-lithiation reagent consists of a solvent tetrahydrofuran, a solute lithium sheet, and biphenyl. After the reaction, the mixture is allowed to air dry to obtain the pre-lithiated zinc stannate anode material (denoted as A9).

[0135] Battery assembly: LiPF6 was added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0136] Electrochemical performance testing:

[0137] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³.-2 The results are shown in Table 9:

[0138] Table 9. Comparison of Battery Performance between A0 and A9

[0139]

[0140] As shown in Table 9, the first-cycle coulombic efficiency was improved by 36.92% after pre-lithiation using 1M biphenyl-lithium-tetrahydrofuran solution vapor, proving that the SEI film generated on the surface of zinc stannate material by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 70.51%, proving that lithium-ion intercalation improved battery stability. Figure 7 and Figure 8 The images show cross-sectional electron microscope (SEM) images of the zinc stannate electrode before and after vapor pre-lithiation. The comparison reveals that the thickness of the electrode loading is significantly increased after vapor pre-lithiation, further confirming that lithium ion intercalation causes the loading to expand. However, its modification effect is weaker compared to Example 1.

[0141] Example 10

[0142] Preparation of pre-lithiation reagent: Prepare a 1.5M biphenyl-lithium-ethylene glycol dimethyl ether solution. First, weigh 1.16g of biphenyl and dissolve it in 5ml of ethylene glycol dimethyl ether solution. Then, dissolve 0.052g of lithium in the mixed solution of biphenyl and ethylene glycol dimethyl ether until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0143] Electrode preparation: The zinc metastannate anode material, binder, and conductive carbon without any treatment are thoroughly mixed in a ratio of 7:2:1, and then coated on copper foil material. After drying and cutting, the zinc metastannate anode sheet is obtained.

[0144] Nitrogen gas was heated to 80°C and then passed into an acetonitrile tank. The nitrogen and acetonitrile mixture was introduced into the steam chamber through the inlet, with the gas flow rate controlled at 80 mL / min. The gas was then recycled through the outlet. The prepared zinc stannate anode sheet (denoted as A0) was placed in a 1.5 M pre-lithiation reagent vapor and reacted for 20 minutes. This pre-lithiation reagent consisted of a solvent tetrahydrofuran, a solute lithium sheet, and biphenyl. After the reaction, the mixture was allowed to air dry to obtain the pre-lithiated zinc stannate anode material (denoted as A10).

[0145] Battery assembly: LiPF6 was added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0146] Electrochemical performance testing:

[0147] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 The results are shown in Table 10:

[0148] Table 10. Comparison of battery performance between A0 and A10

[0149]

[0150] As can be seen from Table 10, the first-cycle coulombic efficiency was improved by 32.48% after pre-lithiation with 1.5M biphenyl-lithium-tetrahydrofuran solution vapor, which proves that the SEI film generated on the surface of zinc stannate material by pre-lithiation reduced irreversible reactions; the capacity retention rate after 100 cycles also increased from 19.93% to 49.23%, which proves that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1 and Example 9.

[0151] Example 11

[0152] Preparation of pre-lithiation reagent: Prepare a 0.5M biphenyl-lithium-ethylene glycol dimethyl ether solution. First, weigh 0.39g of biphenyl and dissolve it in 5ml of ethylene glycol dimethyl ether solution. Then, dissolve 0.017g of lithium in the mixed solution of biphenyl and ethylene glycol dimethyl ether until the solution turns dark blue. Let it stand for 12h to obtain the desired solution.

[0153] Electrode preparation: The zinc metastannate anode material, binder, and conductive carbon without any treatment are thoroughly mixed in a ratio of 7:2:1, and then coated on copper foil material. After drying and cutting, the zinc metastannate anode sheet is obtained.

[0154] Nitrogen gas is heated to 80°C and then passed into an acetonitrile tank. The nitrogen and acetonitrile mixture is introduced into the steam chamber through the inlet, with the gas flow rate controlled at 80 mL / min. The gas is then recycled through the outlet. The prepared zinc stannate anode sheet (denoted as A0) is placed in a 0.5 M pre-lithiation reagent vapor and reacted for 20 minutes. This pre-lithiation reagent consists of a solvent tetrahydrofuran, a solute lithium sheet, and biphenyl. After the reaction, the mixture is allowed to air dry to obtain the pre-lithiated zinc stannate anode material (denoted as A11).

[0155] Battery assembly: LiPF6 was added to a solution of ethylene carbonate (EC) and dimethyl carbonate (DMC) (volume ratio 1:1), a glass fiber membrane (GE Whatman) was used as the separator, and a 1.0 mol / L LiPF6 / ethylene carbonate (EC) + diethyl carbonate (DEC) solution (EC:DEC = 1:1, vol%) was used as the electrolyte. CR2032 button cells were assembled in an argon glove box.

[0156] Electrochemical performance testing:

[0157] Electrochemical performance tests were conducted on the battery using a LAND battery tester manufactured by Wuhan Jinno Electronics Co., Ltd. The charge / discharge voltage range was 0.01V to 3V, and the current density was 1C (866.6 mA g). -1 The loading density of the anolyte film is approximately 1.5 mg / cm³. -2 The results are shown in Table 11:

[0158] Table 11. Comparison of battery performance between A0 and A11

[0159]

[0160]

[0161] As can be seen from Table 11, the first-cycle coulombic efficiency improved by only 4.31% after pre-lithiation using 0.5M biphenyl-lithium-tetrahydrofuran solution vapor, proving that the SEI film generated on the surface of zinc stannate material by pre-lithiation reduced irreversible reactions, but the effect was poor due to the low concentration; the capacity retention rate after 100 cycles also increased from 19.93% to 50.64%, proving that lithium ion intercalation improved battery stability, but the modification effect was weaker compared with Example 1 and Example 9.

[0162] Based on the analysis of all the above embodiments, it can be concluded that the reagent formulation with the best pre-lithiation effect is a biphenyl-lithium-tetrahydrofuran solution, with an optimal concentration of 1M and an optimal reaction time of 20 minutes. Analysis suggests that excessively high concentrations or excessively long reaction times will lead to over-reaction and saturation, while excessively low concentrations or excessively short reaction times will result in insufficient reaction, failing to replenish enough lithium ions to compensate for the lithium deficiency.

[0163] Where there is no conflict, the above embodiments and features described herein can be combined with each other.

[0164] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a zinc metastannate anode material, characterized in that, Includes the following steps: S1. Dissolve an appropriate amount of sodium stannate, zinc acetate, and urea in a mixed solution of ethanol and deionized water. After uniform mixing, the solution is dried by hydrothermal heating, centrifugation, and calcination to obtain zinc metastannate powder. S2. Dissolve the lithiation reagent and metallic lithium in a solvent to obtain a chemical prelithiation reagent solution; S3. The prepared zinc stannate powder is placed in a chemical pre-lithiation reagent solution or in a chemical pre-lithiation reagent vapor and then dried under vacuum to obtain the chemically pre-lithiated zinc stannate anode material. In step S2, the chemical pre-lithiation solvent includes at least one or more of tetrahydrofuran, ethylene glycol dimethyl ether, methyl propyl ether, methyl butyl ether, methyl pentyl ether, ethyl propyl ether, ethyl butyl ether, ethyl pentyl ether, propyl butyl ether, propyl pentyl ether, methyl tetrahydrofuran, dimethyl tetrahydrofuran, ethyl tetrahydrofuran, diethyl tetrahydrofuran, phenyl tetrahydrofuran, 1,2-dimethoxyethane, and diethylene glycol dimethyl ether; In step S2, the lithium-ionizing agent includes at least one or more of the following: biphenyl, naphthalene, methylnaphthalene, dimethylnaphthalene, tetramethylnaphthalene, anthracene, methylanthracene, dimethylanthracene, tetramethylphenanthrene, phenanthrene, methylphenanthrene, dimethylphenanthrene, trimethylphenanthrene, tetramethylphenanthrene, pyrene, methylpyrene, dimethylpyrene, trimethylpyrene, tetramethylpyrene, methylpyrene, dimethylpyrene, trimethylpyrene, tetramethylpyrene, methylbiphenyl, dimethylbiphenyl, and tetramethylbiphenyl; in step S2, the lithium metal includes at least one or more of the following: lithium sheet and lithium strip.

2. The preparation method according to claim 1, characterized in that, In step S1, the molar ratio of tin to zinc is 1:1, and the volume ratio of ethanol to deionized water is 1:(1~3); the mixing method is any one of stirring or ultrasonication, and the mixing time is 0.1~3h; the hydrothermal temperature is 150~180℃, and the time is 4~6h; the centrifugal speed is 7200~7800r / min, and the time is 3~5min; the drying treatment is any one of atmospheric pressure drying, vacuum drying, spray drying, microwave drying, and infrared drying, and the drying temperature is 40~120℃; the calcination conditions are a temperature of 450~650℃, a heating rate of 2~10℃ / min, a calcination time of 2~6h, and a calcination atmosphere of any one of dry air, nitrogen, or argon; then, the product is obtained by natural cooling to room temperature.

3. The preparation method according to claim 1, characterized in that, In step S3, the reaction time in the chemical pre-lithiation reagent solution is 5-60 min.

4. A zinc metastannate anode material prepared by the preparation method according to any one of claims 1-3.

5. A zinc metastannate negative electrode sheet, characterized in that, The zinc stannate anode material, binder, and conductive carbon described in claim 4 are thoroughly mixed in a certain proportion, then coated onto copper foil material, and obtained after drying and cutting.

6. The zinc metastannate negative electrode sheet as described in claim 5, characterized in that, The zinc stannate anode sheet comprises at least the following components: 50-99 wt% zinc stannate anode material, 0.5-40 wt% conductive agent, and 0.5-10 wt% binder; the conductive agent comprises at least one or more of acetylene black, Ketjen black, Super P, MCMB, and carbon nanotubes; the binder comprises at least one or more of polyvinylidene fluoride, polyvinyl chloride, polyvinyl butyral, polyacrylonitrile, polyacrylic acid, polyethylene glycol, polypyrrole, polyaniline, sucrose, glucose, maltose, citric acid, asphalt, furfural resin, epoxy resin, phenolic resin, sodium alginate, and carboxymethyl cellulose.

7. An electrode, characterized in that, Including the zinc metastannate negative electrode sheet as described in claim 5 or 6.

8. A lithium-ion secondary battery, characterized in that, Includes the electrode as described in claim 7.

Images