Method for preparing gel polymer electrolyte, gel polymer electrolyte and application

Abstract

This invention provides a method for preparing a gel polymer electrolyte, the gel polymer electrolyte itself, and its applications, comprising the following steps: Step S1, preparing a fiber membrane as a support membrane using electrospinning, and drying the support membrane to obtain a support fiber membrane; Step S2, cutting the dried support fiber membrane into the required size using a cutting machine and placing it in an argon-filled box for later use; Step S3, preparing a precursor solution; Step S4, placing the lithium sheet, positive electrode material, steel sheet, and spring sheet required for assembling a coin cell into the positive electrode shell in sequence, and placing the support fiber membrane on the surface of the lithium sheet; Step S5, adding the precursor solution dropwise onto the support fiber membrane, heating to initiate free radical polymerization, and generating the gel polymer electrolyte in situ. The gel polymer electrolyte prepared by this invention has high room temperature conductivity, high lithium-ion transference number, high electrochemical stability window, and good cycle performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium battery, in particular to a preparation method of gel polymer electrolyte, gel polymer electrolyte and application. BACKGROUND

[0002] At present, the global industrial production is rapid, and fossil energy such as oil and coal is consumed in large quantities, which causes irreversible environmental damage, and the development of an environmentally friendly energy system is imperative. At the same time, the rapid development of mobile electronic devices and electric vehicles also brings great challenges to human existing energy systems, and designing and developing a new generation of renewable clean energy system has become an important test for mankind. In the existing energy storage system, the most widely used is the lithium ion battery, which has many advantages such as environmental friendliness and long cycle life, so it occupies a place in portable energy storage systems. In the early 20th century, Sony Corporation of Japan successfully mass-produced rechargeable lithium ion batteries, since then, mankind has entered a rapid stage of energy storage development. However, it is worrying that in the use process, the current lithium ion battery has many unavoidable safety problems such as system thermal runaway; more worrying is that the energy density of the traditional lithium ion battery will soon reach the theoretical limit, and it cannot meet the needs of production and life for higher energy density and higher power density energy storage devices.

[0003] Under the current environmental and energy situation, one of the ideal strategies to solve the current problem is to optimize the battery system from the perspective of electrolyte - convert the traditional liquid electrolyte into solid-state electrolyte. This is because solid-state electrolyte shows greater advantages in the development of lithium metal and other high-capacity positive electrode materials. According to the system state, the polymer solid-state electrolyte system can be divided into two categories - gel polymer electrolyte and all-solid-state polymer electrolyte. The difference between the two is that in the all-solid-state system, the raw materials are only polymer monomers and lithium salts that can be dissolved therein and maintain ion transport capacity. The process of ion transport in this system is: first, the lithium salt dissociates and forms free-moving electrons; next, ion transport is achieved with the help of polymer molecular chain movement. Compared with all-solid-state polymer electrolyte, since the gel polymer electrolyte has a three-dimensional network structure that can effectively store organic electrolyte, it can combine the advantages of liquid and solid electrolytes, and thus can better meet the charge and discharge requirements of lithium batteries in current production and life, and is expected to become the electrolyte of the next generation of commercial lithium batteries.

[0004] However, the lithium battery electrolyte manufactured by the above method has poor performance of the gel polymer electrolyte prepared by a single polymer matrix, low conductivity, low lithium ion transference number, and poor cycle performance, which cannot meet the energy storage requirements of production and life. SUMMARY

[0005] In view of the above related technical deficiencies, the present application provides a preparation method of a gel polymer electrolyte with high room temperature conductivity, high lithium ion transference number, high electrochemical stability window, and good cycle performance.

[0006] To solve the above technical problems, in a first aspect, the present application provides a preparation method of a gel polymer electrolyte, comprising the following steps:

[0007] Step S1: using an electrospinning method to prepare one or more of PAN fiber membranes, PVDF fiber membranes, PVDF-HFP fiber membranes, PVA fiber membranes, PVP fiber membranes, PMMA fiber membranes, and PU fiber membranes as support film for standby, and drying the support film to obtain a support fiber membrane;

[0008] Step S2: cutting the dried whole piece of the support fiber membrane into the required size by a cutting machine, and placing it in an argon-filled glove box for standby;

[0009] Step S3: adding a predetermined amount of tetraethyl acetylcitrate, 2,2,2,3,3,3-hexafluorobutyl ester, an initiator, and an organic electrolyte into a clean and dry reagent bottle, and fully stirring to obtain a precursor solution;

[0010] Step S4: placing lithium sheets, positive electrode materials, steel sheets, and spring sheets required for assembling a button cell into a positive electrode shell in sequence, and placing the support fiber membrane on the surface of the lithium sheets;

[0011] Step S5: dropping the precursor solution onto the support fiber membrane, heating to initiate free radical polymerization, and generating a gel polymer electrolyte in situ.

[0012] Preferably, in the step S1, the parameters of the electrospinning include an applied voltage, a spinning receiving drum speed, a spinning temperature, and a spinning liquid injection rate, wherein the applied voltage is 20 KV, the spinning receiving drum speed is 300 r / min, the spinning temperature is room temperature, and the spinning liquid injection rate is 0.8 mL / h.

[0013] Preferably, in the step S1, after the spinning is completed, the support film is transferred to a vacuum drying box, and the excess organic solvent is removed by vacuum drying to obtain a support fiber membrane.

[0014] Preferably, in the step S2, the moisture in the argon-filled glove box is ≤0.01 ppm, and the oxygen is ≤0.01 ppm.

[0015] Preferably, the step S3 specifically comprises the following sub-steps:

[0016] First, a certain amount of the tetraisopropyl titanate, 2,2,2,3,3,3-hexafluorobutyl ester, and initiator are added to a reagent bottle, and after the moisture and oxygen content in the reagent bottle are controlled to a predetermined value, an organic electrolyte is added to the reagent bottle, and a precursor solution is obtained by stirring at room temperature.

[0017] Preferably, the mass ratio of the tetraisopropyl titanate and the 2,2,2,3,3,3-hexafluorobutyl ester is 3:2, and the amount of the organic electrolyte added is 60%-95%.

[0018] Preferably, in the step S4, a certain amount of the precursor solution is added dropwise on the PAN film by using a pipette, and after the precursor solution is fully immersed in the polyacrylonitrile fiber film, a steel sheet, a spring, and a negative electrode shell are sequentially placed, and the assembled button cell is sealed by using a button cell sealing machine; the assembled button cell is prepared in an argon-filled glove box, and the moisture content in the argon-filled glove box is ≤0.01 ppm, and the oxygen content is ≤0.01 ppm.

[0019] Preferably, in the step S5, the temperature for thermally initiating the precursor solution to form a gel polymer electrolyte in the button cell is 60℃.

[0020] In a second aspect, an embodiment of the present application provides a gel polymer electrolyte prepared by the above method.

[0021] In a third aspect, an embodiment of the present application provides an application of the gel polymer electrolyte, which is applied to a button cell.

[0022] Compared with the related art, the gel polymer electrolyte is prepared by the preparation method of the steps S1-S5, which is simple and easy to operate; compared with the traditional non-in-situ preparation technology (such as the casting method), the preparation method used in the present application can effectively avoid the generation of a large amount of organic waste liquid and waste gas, and has small environmental pollution, and is expected to be mass-produced in industry; at the same time, the gel polymer electrolyte prepared has a high electrochemical stability window value, a high room temperature conductivity, a high lithium ion transference number, and good cycle performance; in addition, the fluorine-rich gel polymer electrolyte prepared in the present application helps to form a stable interfacial film (CEI) between the gel polymer electrolyte and the positive electrode, and effectively alleviates the volume expansion problem of NCM811 and other nickel-rich high-pressure materials in the cycle process. BRIEF DESCRIPTION OF DRAWINGS

[0023] The present application will be described in detail below with reference to the accompanying drawings. The above or other aspects of the present application will become more apparent and more readily appreciated by referring to the following detailed description, taken in conjunction with the accompanying drawings. In the drawings:

[0024] Figure 1Flow chart of the preparation method of the gel polymer electrolyte of the present application;

[0025] Figure 2 SEM image of GPE 3:2 obtained from Example 1;

[0026] Figure 3 Electrochemical stability test graph of GPE 3:2 obtained from Example 1;

[0027] Figure 4 First charge-discharge capacity curve of the assembled battery of GPE 3:2 obtained from Example 1;

[0028] Figure 5 Conductivity test graph of GPE 3:2 obtained from Example 1;

[0029] Figure 6 1C rate long cycle test curve of the assembled battery of GPE 3:2 obtained from Example 1;

[0030] Figure 7 SEM image of GPE 1:1 obtained from Example 2;

[0031] Figure 8 Electrochemical stability test graph of GPE 1:1 obtained from Example 2;

[0032] Figure 9 First charge-discharge capacity curve of the assembled battery of GPE 1:1 obtained from Example 2;

[0033] Figure 10 Conductivity test graph of GPE 1:1 obtained from Example 1;

[0034] Figure 11 Constant current charge-discharge test curve of the assembled battery of PE-GPE obtained from Example 3. DETAILED DESCRIPTION

[0035] The specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0036] The specific embodiments / examples described herein are specific embodiments of the present application, which are used to illustrate the concept of the present application, and are explanatory and exemplary, and should not be interpreted as limiting the embodiments of the present application and the scope of the present application. In addition to the examples described herein, those skilled in the art can also employ other technical solutions that are obvious based on the disclosure of the claims and the specification of the present application, which include technical solutions that make any obvious substitutions and modifications to the examples described herein, and are within the protection scope of the present application.

[0037] Example 1

[0038] AsFigures 1-6 As shown, the present application provides a preparation method of a gel polymer electrolyte, comprising the following steps:

[0039] Step S1, using electrospinning method to prepare one or more of PAN fiber membrane (polyacrylonitrile fiber membrane), PVDF fiber membrane (polyvinylidene fluoride fiber membrane), PVDF-HFP fiber membrane (poly (vinylidene fluoride-co-hexafluoropropylene)), PVA fiber membrane (polyvinyl alcohol membrane), PVP fiber membrane (polyvinylpyrrolidone membrane), PMMA fiber membrane (polymethyl methacrylate membrane), PU fiber membrane (polyurethane membrane) as support film, dry the support film to obtain a support fiber membrane.

[0040] Specifically, one of PAN powder, PVDF powder, PVDF-HFP powder, PVA powder, PVP powder, PMMA powder, PU powder is added to N,N-dimethylformamide solution, and the electrospinning solution is prepared by stirring at room temperature. A certain amount of electrospinning solution is taken with a syringe, and one or more of PAN fiber membrane, PVDF fiber membrane, PVDF-HFP fiber membrane, PVA fiber membrane, PVP fiber membrane, PMMA fiber membrane, PU fiber membrane is prepared as a support film by using electrospinning technology.

[0041] Preferably, in the step S1, the technical parameters of electrospinning include applied voltage, spinning receiving drum speed, spinning temperature and spinning liquid injection rate, wherein the applied voltage is 20KV, the spinning receiving drum speed is 300r / min, the spinning temperature is room temperature, and the spinning liquid injection rate is 0.8mL / h.

[0042] Preferably, in the step S1, after spinning, the support film is transferred to a vacuum drying box, and the excess organic solvent is removed by vacuum drying to obtain a support fiber membrane.

[0043] Step S2, the whole piece of the dried support fiber membrane is cut into the required size by a cutting machine, and is placed in an argon-filled glove box for standby.

[0044] Preferably, in the step S2, the moisture of the argon-filled glove box is ≤0.01ppm, and the oxygen is ≤0.01ppm.

[0045] Step S3, a predetermined amount of isoprene tetraacrylate, 2,2,2,3,3,3-hexafluorobutyl ester, initiator and organic electrolyte are added to a clean and dry reagent bottle, and are fully stirred to obtain a precursor solution. The obtained precursor solution is mixed uniformly, and the reaction effect is good.

[0046] Preferably, the step S3 specifically comprises the following sub-steps: firstly, a certain amount of the tetraisopropyl titanate, 2,2,2,3,3,3-hexafluorobutyl ester and initiator are added into a reagent bottle, and then the moisture and oxygen values in the reagent bottle are controlled at predetermined values, and then the organic electrolyte is added into the reagent bottle, and the precursor solution is obtained by fully stirring under room temperature.

[0047] Preferably, the mass ratio of the tetraisopropyl titanate and the 2,2,2,3,3,3-hexafluorobutyl ester is 3:2, and the amount of the organic electrolyte added is 60%-95%.

[0048] Step S4: lithium sheets, positive electrode materials, steel sheets and elastic sheets required for assembling the button cell are sequentially placed into the positive electrode shell, and the support fiber membrane is placed on the surface of the lithium sheet.

[0049] Preferably, in the step S4, the support fiber membrane is a PAN membrane. A certain amount of the precursor solution is added dropwise on the PAN membrane by using a pipette, and then the steel sheet, the elastic sheet and the negative electrode shell are sequentially placed after the precursor solution is fully immersed into the polyacrylonitrile fiber membrane, and the assembled button cell is sealed by using a button cell sealing machine; the assembly of the button cell is carried out in an argon-filled glove box, and the moisture in the argon-filled glove box is ≤0.01 ppm and the oxygen is ≤0.01 ppm.

[0050] Step S5: the precursor solution is added dropwise on the support fiber membrane, and the radical polymerization is initiated by heating to generate the gel polymer electrolyte in situ.

[0051] Preferably, in the step S5, the temperature for initiating the precursor solution to form the gel polymer electrolyte in the button cell is 60°C. The sealed button cell is heated to initiate the in-situ polymerization of the precursor solution to generate the gel polymer electrolyte GPE3:2 with good interfacial compatibility. The heating temperature is 60°C.

[0052] Figure 2 The SEM image of the prepared GPE3:2 is shown in the SEM image, and the prepared GPE3:2 still maintains the skeleton structure of the polyacrylonitrile fiber membrane, which will help the transmission of lithium ions.

[0053] The electrochemical stability test is carried out by using a steel symmetric cell, wherein the working electrode and the reference electrode are both steel sheets, and the LSV curve is obtained by testing the steel sheets. Figure 3 It is shown that the electrochemical stability window value of the GPE3:2 is as high as 5.35V. Figure 5 The test results show that the ionic conductivity of the GPE at a test temperature of 30°C reaches 4.06×10 -3 S cm -2 .

[0054] The full battery is assembled in the order of positive shell-positive electrode-polyacrylonitrile fiber membrane-negative electrode-elastic sheet-steel sheet-negative shell, and the first circle charge and discharge capacity is tested, and the test results are shown in Figure 4 The positive electrode adopts a nickel-cobalt-manganese ternary material, wherein the mass ratio of nickel, cobalt and manganese elements is 8:1:1. Figure 4 The test results show that under room temperature conditions, when the positive electrode material is discharged at 0.1C constant current, the first circle coulombic efficiency can reach 91.36%. Figure 6 The test results show that under room temperature conditions, when the positive electrode material is discharged at 1C constant current for 300 cycles, the capacity retention rate is 76%.

[0055] Example 2

[0056] The present application relates to a kind of preparation methods of gel polymer electrolyte, comprising the following steps:

[0057] Step S1: add one of PAN powder, PVDF powder, PVDF-HFP powder, PVA powder, PVP powder, PMMA powder and PU powder to N,N-dimethylformamide solution, and prepare electrospinning solution under room temperature stirring. A certain amount of electrospinning solution is taken with a syringe, and one or more of PAN fiber membrane, PVDF fiber membrane, PVDF-HFP fiber membrane, PVA fiber membrane, PVP fiber membrane, PMMA fiber membrane and PU fiber membrane are prepared as support film by using electrospinning technology. The technical parameters of electrospinning are: applied voltage: 20KV, spinning receiving drum speed: 300r / min, spinning temperature: room temperature, spinning liquid injection rate: 0.8mL / h. After spinning, the spinning fiber membrane is quickly transferred to a vacuum drying oven, and the excess organic solvent is removed by vacuum drying.

[0058] Step S2: the whole piece of polyacrylonitrile fiber film after drying is cut into the required size by using a cutting machine, and is placed in an argon-filled glove box for standby. The moisture content of the argon-filled glove box is less than 0.01ppm, and the oxygen content is less than 0.01ppm.

[0059] Step S3: a certain amount of tetraisopropyl isopropylate and 2,2,2,3,3,3-hexafluorobutyl ester is added to the reagent bottle, wherein the ratio of the amount of the two is 1:1. A small amount of initiator is added to the reagent bottle, wherein the added initiator is a commonly used free radical polymerization initiator, azobisisobutyronitrile. Finally, a certain amount of organic electrolyte is added to the reagent bottle, wherein the amount of organic electrolyte added is 60% to 95%. Stir under room temperature to form a precursor solution for standby.

[0060] Step S4: lithium sheet, positive electrode material, steel sheet, spring, and negative electrode shell are sequentially placed in the positive electrode shell, and a support fiber film is placed on the surface of the lithium sheet, wherein the support fiber film is a PAN film. A certain amount of precursor solution is taken by a pipette and dropped on the PAN film, wherein the precursor solution needs to be fully immersed in the polyacrylonitrile fiber film before the steel sheet, spring and negative electrode shell are sequentially placed. The assembled button cell is sealed by a button cell sealing machine. The button cell is assembled in an argon-filled glove box, and the moisture in the argon-filled glove box is less than 0.01 ppm and the oxygen is less than 0.01 ppm.

[0061] Step S5: The sealed button cell is heated to initiate in-situ polymerization of the precursor solution to generate a gel polymer electrolyte GPE1:1 with good interfacial compatibility. The heating temperature is 60 DEG C.

[0062] Figure 7 The SEM image of the prepared GPE1:1 is shown in the SEM image. The surface of the prepared GPE1:1 is similar to that of the GPE3:2, maintaining the fiber structure of the polyacrylonitrile, and no obvious pores are observed.

[0063] The electrochemical stability test is carried out by using a steel symmetric cell, wherein the working electrode and the reference electrode are both steel sheets, and the LSV curve is obtained by testing. Figure 8 It is shown that the electrochemical stability window value of the GPE1:1 is 4.8 V. Figure 10 The test results show that the ionic conductivity of the GPE at a test temperature of 30 DEG C reaches 3.59*10 -3 S cm -2

[0064] The full cell is assembled in the order of positive electrode shell-positive electrode-polyacrylonitrile fiber film-negative electrode-spring-steel sheet-negative electrode shell, and the first cycle charge and discharge capacity is tested, and the test results are shown in the figure. The positive electrode is made of a nickel-cobalt-manganese ternary material, wherein the mass ratio of nickel, cobalt and manganese elements is 8:1:1. Figure 9 The test results show that under room temperature conditions, when the positive electrode material is discharged at a constant current of 0.1 C, the first cycle coulombic efficiency can reach 89.19%.

[0065] Example 3

[0066] The present application relates to a preparation method of a gel polymer electrolyte, comprising the following steps:

[0067] Step S1: dry clean commercial PP film and PE film for standby. One or more of the commercial polyethylene film (PE film) and the commercial polypropylene film (PP film) is selected as the support of the gel polymer electrolyte.

[0068] Step S2: using a cutting machine to cut the dried whole piece of standby film into the required size, and storing it in an argon-filled glove box. Among them, the moisture of the argon-filled glove box is <0.01ppm, and the oxygen is <0.01ppm.

[0069] Step S3: a certain amount of tetraacetyl isopentyloctyl ester, 2,2,2,3,3,3-hexafluorobutyl ester, and a small amount of initiator are added to the reagent bottle. Finally, a certain amount of organic electrolyte is added to the reagent bottle, and similarly, the amount of organic electrolyte added is 60% to 95%.

[0070] Step S4: the lithium sheet, steel sheet, spring sheet required for assembling the button cell are sequentially placed in the positive shell, and the support film is placed on the surface of the lithium sheet, wherein one of PP film and PE film is selected. A certain amount of precursor solution is taken out by a pipette and added to the support film, and the steel sheet, spring sheet and negative shell are sequentially placed after the precursor solution is fully immersed in the support film. The assembled button cell is sealed by using a button cell sealing machine. Among them, the assembly of the button cell is carried out in an argon-filled glove box, and the moisture of the argon-filled glove box is <0.01ppm, and the oxygen is <0.01ppm.

[0071] Step S5: the sealed button cell is heated to initiate in-situ polymerization of the precursor solution to generate gel polymer electrolyte PP-GPE or PE-GPE in-situ. Among them, the heating temperature is 60℃.

[0072] Figure 11 The constant current charge-discharge test result graph of the lithium symmetric battery assembled by the prepared PE-GPE. Among them, the test current size is 0.1mA·cm -2 .

[0073] The lithium symmetric battery is assembled in the order of positive shell-lithium sheet-support film-lithium sheet-spring sheet-steel sheet-negative shell, and the test result is shown in Figure 11 .

[0074] The embodiment of the present application provides a kind of gel polymer electrolyte, and the gel polymer electrolyte is made of the preparation method of above-mentioned lithium battery aluminum foil. The gel polymer electrolyte prepared, its electrochemical stable window value is high, room temperature conductivity is high, lithium ion transference number is high, cycle performance is good, and has good interface compatibility, can effectively deal with the problem caused by poor solid-solid interface compatibility.

[0075] The application provides application of the gel polymer electrolyte, and the application of the gel polymer electrolyte is not limited to a button cell. Other various types of batteries, such as a soft package battery, a square aluminum shell battery, a cylindrical battery and the like, are also included. When the gel polymer electrolyte is applied to an electrolyte film of a quasi-solid lithium battery, the electrochemical stability window value is high, the room temperature conductivity is high, the lithium ion transference number is high, the cycle performance is good, and the gel polymer electrolyte has good interface compatibility, and can effectively cope with problems caused by poor solid-solid interface compatibility.

[0076] The above merely provides the preferred embodiments of the application, but is not intended to limit the application. For those skilled in the art, the application can have various modifications and changes. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the application shall be included in the scope of the claims of the application.

Claims

1. A method for producing a gel polymer electrolyte, characterized by, The preparation method comprises the following steps: Step S1, using an electrospinning method to prepare one or more of PAN fiber membrane, PVDF fiber membrane, PVDF-HFP fiber membrane, PVA fiber membrane, PVP fiber membrane, PMMA fiber membrane, PU fiber membrane as a support film, drying the support film to obtain a support fiber membrane; Step S2, cutting the dried whole piece of the support fiber membrane into the required size by a cutting machine, and placing it in an argon-filled glove box for standby; Step S3, adding a predetermined amount of tetra (2, 2, 2, 3, 3, 3-hexafluorobutyl) isopentyldiacrylate, 2, 2, 2, 3, 3, 3-hexafluorobutyl, initiator and organic electrolyte into a clean and dry reagent bottle, and fully stirring to obtain a precursor solution; Step S4, placing lithium sheet, positive electrode material, steel sheet and spring sheet required for assembling the button cell into the positive electrode shell in sequence, and placing the support fiber membrane on the surface of the lithium sheet; Step S5, dropping the precursor solution onto the support fiber membrane, heating to initiate free radical polymerization, and generating a gel polymer electrolyte in situ; In the step S1, the parameters of the electrospinning include applied voltage, spinning receiving drum speed, spinning temperature and spinning liquid injection rate, wherein the applied voltage is 20KV, the spinning receiving drum speed is 300r / min, the spinning temperature is room temperature, and the spinning liquid injection rate is 0.8mL / h; In the step S1, after the spinning is completed, the support film is transferred to a vacuum drying box, and the excess organic solvent is removed by vacuum drying to obtain a support fiber membrane.

2. The method for preparing a gel polymer electrolyte according to claim 1, wherein In the step S2, the moisture in the argon-filled glove box is ≤0.01ppm, and the oxygen is ≤0.01ppm.

3. The method for preparing a gel polymer electrolyte according to claim 1, wherein The step S3 specifically comprises the following substeps: First, a certain amount of tetra (2, 2, 2, 3, 3, 3-hexafluorobutyl) isopentyldiacrylate, 2, 2, 2, 3, 3, 3-hexafluorobutyl and initiator are added to the reagent bottle, the moisture and oxygen content in the reagent bottle are controlled at a predetermined value, then the organic electrolyte is added to the reagent bottle, and the precursor solution is fully stirred under room temperature conditions.

4. The method for preparing a gel polymer electrolyte according to claim 3, wherein the gel polymer electrolyte is prepared by adding the electrolyte solution to the polymer gel. The mass ratio of the tetra (2, 2, 2, 3, 3, 3-hexafluorobutyl) isopentyldiacrylate and the 2, 2, 2, 3, 3, 3-hexafluorobutyl is 3:2; and the amount of the organic electrolyte added is 60%-95%.

5. The method for preparing a gel polymer electrolyte according to claim 3, wherein the gel polymer electrolyte is prepared by adding the electrolyte solution to the polymer gel. In the step S4, a certain amount of precursor solution is dropped onto the support fiber membrane by using a pipette, and after the precursor solution is fully immersed in the support fiber membrane, the steel sheet, spring sheet and negative electrode shell are placed in sequence, and the assembled button cell is sealed by using a button cell sealing machine; the assembly of the button cell is carried out in an argon-filled glove box, and the moisture in the argon-filled glove box is ≤0.01ppm, and the oxygen is ≤0.01ppm.

6. The method for preparing a gel polymer electrolyte according to claim 1, wherein the gel polymer electrolyte is prepared by adding the electrolyte solution to the polymer gel. In the step S5, the temperature for heating the precursor solution to form a gel polymer electrolyte inside the button cell is 60℃.

7. A gel polymer electrolyte characterized by, The gel polymer electrolyte is made by the method of any one of claims 1 to 6.

8. The use of the gel polymer electrolyte according to claim 7 in a button cell.

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