Method for preparing a fluorinated graphene film and battery

Abstract

The application provides a preparation method of a fluorinated graphene film and a battery. Fluorinated graphene and carbon nanotubes are mixed and infiltrated in a mixed solution of anhydrous ethanol and deionized water, a reducing defluorination mixed solution and a polyvinyl alcohol aqueous solution are added and ultrasonically treated, vacuum filtration is performed, drying is performed, and a fluorinated graphene film is obtained by peeling off the filter film. The fluorine content of the fluorinated graphene film is 33-45%, the metal particle doping amount is 7.45-16.7 wt%, and the active material surface load is 3.32-5.24 mg / cm 2 The application is a one-step continuous process. The fluorine content of the fluorinated graphene is reduced by reducing defluorination, the conductive metal particles are reduced, the hydrogen bond synergistic effect formed by the hydroxyl groups of the polyvinyl alcohol is utilized to construct a stable self-supporting three-dimensional conductive network structure, the hydrophilicity of the fluorinated graphene film is improved, the low tap density fluorinated graphene surface load is improved, the conductivity of the fluorinated graphene film is improved, the polarization in the discharge process is reduced, and the application of the lithium / fluorinated carbon battery in high-power electronic devices is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery electrode preparation, and in particular to a preparation method of fluorinated graphene film and a battery. BACKGROUND

[0002] Lithium / carbon fluoride battery has the advantages of long service life, small self-discharge, wide working temperature, environmental friendliness, etc., and has broad application prospects in the fields of portable electronic devices, implanted medical devices and equipment power supplies. The fluorinated graphene with low-dimensional nanostructure can improve the conductivity of the fluorinated carbon material to some extent, but in the case of increasing the surface loading of active material, the electrode prepared by the traditional slurry coating method of light fluorinated graphene positive electrode material is prone to deformation or damage due to the low tap density characteristics of the material, and it is difficult to prepare a perfect electrode.

[0003] Therefore, the surface loading of active material can be improved by preparing fluorinated graphene film, but fluorinated graphene is the product of edge fluorination of graphene, and with the introduction of fluorine atoms and the increase of fluorination degree, fluorinated graphene quickly decreases from conductor to insulator, so the fluorinated graphene film prepared by the conventional method has certain hydrophobicity and insulation, and is difficult to be applied in lithium / carbon fluoride battery system. SUMMARY

[0004] Therefore, the present application provides a preparation method of fluorinated graphene film and a battery, which can reduce the fluorine content, construct a metal conductive layer and a self-supporting three-dimensional conductive network structure in one step, improve the hydrophilicity of the fluorinated graphene film, and increase the surface loading of active material and the conductivity. The fluorinated graphene film prepared by the method not only has multiple effects, but also is beneficial to improve the electrochemical performance of lithium / carbon fluoride battery.

[0005] To achieve the above purpose, the present application provides the following technical solutions:

[0006] The fluorinated graphene and carbon nanotubes are mixed and infiltrated in a mixed solution of anhydrous ethanol and deionized water, and then a reduction and defluorination mixed solution is added to reduce the defluorination of fluorinated graphene and the reduction of conductive metal particles. The reduction and defluorination mixed solution is composed of a metal salt solution and a reducing agent;

[0007] A polyvinyl alcohol aqueous solution with hydroxyl groups and hydrogen bonds between the groups is added as a binder, which is ultrasonically dispersed and then vacuum filtered, dried and peeled off the filter membrane to obtain a fluorinated graphene film. The fluorine content of the fluorinated graphene film is 33-45%, the metal particle doping amount is 7.45-16.7wt%, and the surface loading of active material is 3.32-5.24mg / cm 2 .

[0008] The method further comprises:

[0009] (1) The fluorinated graphene and carbon nanotubes are soaked in anhydrous ethanol solution, stirred for 10 min, and then ultrasonicated for 30 min. After alcohol washing to remove impurities, they are soaked in deionized water and anhydrous ethanol to form a first mixed solution;

[0010] (2) The mixed solution I is added to the sensitization solution in a volume ratio of 1:9 for 1 h, washed to remove impurities, and soaked in deionized water and anhydrous ethanol to form a second mixed solution;

[0011] (3) The second mixed solution is added to 90 mL of a reducing defluorination mixed solution in one step for 10-40 min, wherein the volume ratio of the metal salt solution to the reducing agent in the reducing defluorination mixed solution is 3:1. At the end of the time, 1 mL of polyvinyl alcohol aqueous solution is added dropwise to the solution, ultrasonicated for 10 min, and then vacuum filtered. The filter membrane is repeatedly washed with deionized water and anhydrous ethanol for 3 times. The polyvinyl alcohol aqueous solution is prepared by dissolving polyvinyl alcohol powder in deionized water at 95°C;

[0012] (4) After drying, the obtained film sample is peeled off to obtain a fluorinated graphene film;

[0013] (5) The fluorinated graphene film is cut into a circular piece with a diameter of 12 mm and directly used as an electrode. A lithium / fluorinated carbon battery is assembled with lithium metal as the counter electrode.

[0014] The tap density of the fluorinated graphene is 0.04-0.05 g / cm 3 , and the fluorine content is 50-60%.

[0015] The carbon nanotubes include at least one of multi-walled carbon nanotubes, single-walled carbon nanotubes, carbon nanowires, carbon nanotube bundles, and serpentine carbon nanotubes.

[0016] The mass percentage of the fluorinated graphene to the carbon nanotubes is 1-5:1, and the concentration of the first mixed solution is 5-10 mg / mL.

[0017] The sensitization solution is prepared by dissolving stannous chloride solid and hydrochloric acid solution in deionized water and anhydrous ethanol in a volume ratio of 1:1. The concentration of stannous chloride in the mixed solution II is 20 g / L, and the concentration of hydrochloric acid is 6 mL / L.

[0018] The reducing agent includes at least one of a combination of glucose and sodium citrate, hydrazine, formaldehyde, and dimethylaminoborane.

[0019] The metal salt includes at least one of nitrate, chloride, and sulfate, and the concentration is 100-300 mmol / L. The conductive metal particles are Ag.

[0020] The molecular weight of the polyvinyl alcohol ranges from 120000 to 150000.

[0021] The filter membrane comprises at least one of a polytetrafluoroethylene membrane, a polyamide membrane and a glass fiber membrane; the drying method is vacuum drying, and the drying time is 8h.

[0022] The application provides a preparation method of a fluorinated graphene membrane and a battery. 2 The fluorine content of the fluorinated graphene membrane is 33-45%, the metal particle doping amount is 7.45-16.7wt%, and the active material surface load is 3.32-5.24mg / cm

[0023] The application has the following beneficial effects:

[0024] (1) Compared with conventional hydrophobic and insulating fluorinated graphene membranes, the application realizes the reduction of fluorine content and the reduction of conductive metal particles in one step through a controllable reduction and defluorination method, and improves the hydrophilicity and conductivity of the fluorinated graphene membrane;

[0025] (2) The application fully utilizes zero-dimensional metal particles and one-dimensional carbon nanotubes with high conductivity, and the hydrogen bonds formed between the hydroxyl groups in polyvinyl alcohol are used to bond the two-dimensional fluorinated graphene, so that a stable self-supporting three-dimensional conductive network structure is constructed, the conductivity of the fluorinated graphene membrane is further improved, the polarization in the discharge process is reduced, and the rate performance of the battery is improved;

[0026] (3) The fluorinated graphene membrane prepared by the method of the application not only does not need a current collector and can be directly used as a battery electrode compared with the traditional slurry coating method, but also can improve the active material surface load of the light fluorinated graphene in the electrode while ensuring good electrochemical performance, effectively solving the problem that the fluorinated graphene with low tap density characteristics cannot improve the active material surface load in the battery electrode. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The fluorinated graphene membrane provided by the first embodiment of the application is shown in the figure.

[0028] Figure 2 A scanning electron microscope image of the fluorinated graphene film provided in Example One of the present application;

[0029] Figure 3 A water contact angle image of the fluorinated graphene film provided in Example One of the present application;

[0030] Figure 4 An infrared spectrum image of the fluorinated graphene film provided in Example One of the present application and Comparative Example Three;

[0031] Figure 5 An 8C rate discharge image of the lithium / fluorinated carbon battery provided in Example One of the present application with the fluorinated graphene film as the electrode. DETAILED DESCRIPTION

[0032] The present application will be further described below in conjunction with the accompanying drawings and examples. It should be understood that the specific examples described herein are intended to be illustrative only and are not intended to limit the present application.

[0033] Example One

[0034] In this example, fluorinated graphene with a tap density of 0.04-0.05 g / cm 3 , a fluorine content of 55%, was used as the raw material to prepare a fluorinated graphene film with a fluorine content of 36%, a metal particle doping amount of 12.04 wt%, and an active material surface loading of 5.09 mg / cm 2 , and the maximum discharge rate of the battery was 8C. The effects of the preparation method provided in this example on the fluorine content, metal particle content, active material surface loading, and battery rate in the fluorinated graphene film were verified through specific tests, as follows:

[0035] (1) The fluorinated graphene and carbon nanotubes were immersed in anhydrous ethanol solution at a mass ratio of 4:1, stirred for 10 min, and then ultrasonicated for 30 min. The alcohol was washed to remove impurities and the mixture was immersed in an equal volume of 1:1 deionized water and anhydrous ethanol. The first mixed solution had a concentration of 10 mg / mL;

[0036] (2) The first mixed solution was added to the sensitizing solution at a volume ratio of 1:9 and sensitized for 1 h. The impurities were removed by washing and the mixture was immersed in deionized water and anhydrous ethanol solution. The second mixed solution had a concentration of 10 mg / mL;

[0037] (3) Configuration of the reduction defluorination mixed solution. Configuration of the reduction solution: dissolve 7.128 g of glucose solid and 1.912 g of trisodium citrate dihydrate in 30 mL of deionized water. Configuration of the metal silver salt solution: dissolve 3.06 g of silver nitrate in 90 mL of deionized water, after stirring until the silver nitrate solution forms a colorless solution, add 2 mg of potassium hydroxide solid according to a molar ratio of 500:1, and then add 15 drops of ammonia water until the solution turns colorless again, to configure a 200 mmol / L metal salt solution;

[0038] (4) Configuration of a 2 wt% polyvinyl alcohol aqueous solution: weigh 1 g of polyvinyl alcohol powder and dissolve it in 50 mL of deionized water at 95°C.

[0039] (5) The second mixed solution after the sensitization treatment is added with the silver-ammonia solution at a volume ratio of 1:9, and stirred at a rotation speed of 300 rpm for 5 min, during which the silver-ammonia mixed solution of fluorinated graphene should be kept in the dark to avoid the influence of direct light on the subsequent reaction effect; 30 mL of the reducing agent at a volume ratio of 1:3 is added to the above mixed solution for reaction for 25 min, after the reaction time ends, 1 mL of the polyvinyl alcohol aqueous solution is added to the mixed solution, and after ultrasonic treatment, vacuum filtration is performed, and ion water and anhydrous ethanol are repeatedly washed alternately for three times; vacuum drying is performed at 50°C for 8 h, the filter membrane is peeled off, and fluorinated graphene film is obtained;

[0040] (6) The prepared fluorinated graphene film is cut into 12 mm round pieces and directly used as an electrode, a metal lithium is used as a counter electrode, and a lithium / fluorinated carbon battery is assembled. The current value required by the lithium / fluorinated carbon battery assembled by the fluorinated graphene film to release the capacity within a specified time is the maximum discharge rate.

[0041] The lithium primary button cell is prepared by using the fluorinated graphene film prepared in this embodiment, and the specific method comprises the following steps: the fluorinated graphene film is vacuum dried for 8 h, and then cut into 12 mm electrode pieces, a metal lithium is used as a counter electrode, a Celgard-2500 series polypropylene separator is used as a separator, and 1M LiBF4 / PC:DME (1:1) is used as an electrolyte; a 2025 button cell is used for assembly, the whole process is carried out in a glove box, and the assembly sequence is a negative electrode shell-lithium piece-electrolyte-separator-electrolyte-electrode piece-gasket-spring piece-positive electrode shell; after assembly, packaging treatment is performed, and finally the performance is tested.

[0042] Example Two

[0043] In this embodiment, the tap density of the fluorinated graphene used as a raw material is 0.04-0.05 g / cm 3 , and the fluorine content is 55%; a fluorinated graphene film with a fluorine content of 33%, a metal particle doping amount of 14.91 wt%, and an active material surface load of 5.05 mg / cm 2The fluorinated graphene film has a maximum battery discharge rate of 5C. The specific implementation method is consistent with Example 1, except that the concentration of the reaction solution is adjusted to 300 mmol / L in step 3 for the experiment.

[0044] Example 3

[0045] In this embodiment, the tap density is 0.04–0.05 g / cm³. 3 A novel active material with a fluorine content of 41%, a metal particle doping amount of 8.02 wt%, and an active material surface loading of 5.03 mg / cm³ was prepared using fluorinated graphene with a fluorine content of 55% as raw material. 2 The fluorinated graphene film allows for a maximum battery discharge rate of 3C. The specific implementation method remains the same as in Example 1, except that the reaction solution concentration was adjusted to 100 mmol / L in step 3.

[0046] Example 4

[0047] In this embodiment, the tap density is 0.04–0.05 g / cm³. 3 A novel active material with a fluorine content of 40%, a metal particle doping amount of 11.39 wt%, and an active material surface loading of 3.32 mg / cm³ was prepared using fluorinated graphene with a fluorine content of 55% as raw material. 2 The fluorinated graphene film has a maximum battery discharge rate of 3C. The specific implementation method is consistent with Example 1, except that in step 1, fluorinated graphene and carbon nanotubes are tested at a mass ratio of 1:1.

[0048] Example 5

[0049] In this embodiment, the tap density is 0.04–0.05 g / cm³. 3 A novel active material with a fluorine content of 43%, a metal particle doping amount of 11.65 wt%, and an active material surface loading of 5.06 mg / cm³ was prepared using fluorinated graphene with a fluorine content of 55% as raw material. 2 The fluorinated graphene film has a maximum battery discharge rate of 5C. The specific implementation method is consistent with Example 1, except that in step 1, the fluorinated graphene and carbon nanotubes are tested at a mass ratio of 5:1.

[0050] Example 6

[0051] In this embodiment, the tap density is 0.04–0.05 g / cm³. 3 A novel active material with a fluorine content of 34%, a metal particle doping amount of 16.70 wt%, and an active material surface loading of 4.98 mg / cm³ was prepared using fluorinated graphene with a fluorine content of 55% as raw material. 2 The fluorinated graphene film has a battery discharge rate of 5C. The specific implementation method is consistent with Example 1, except that the reaction time in step 5 is adjusted to 40 minutes for the experiment.

[0052] Example Seven

[0053] In this example, fluorinated graphene with a tap density of 0.04-0.05 g / cm 3 and a fluorine content of 55% was used as a raw material to prepare a fluorinated graphene film with a fluorine content of 45%, a metal particle doping amount of 7.45 wt%, and an active material surface loading of 4.96 mg / cm 2 The maximum discharge rate of the battery was 3C. The specific implementation was consistent with Example One, except that the reaction time was adjusted to 10 min in Step 5.

[0054] Example Eight

[0055] In this example, fluorinated graphene with a tap density of 0.04-0.05 g / cm 3 and a fluorine content of 55% was used as a raw material, and the specific implementation was consistent with Example One, except that the amount of polyvinyl alcohol aqueous solution added in Step 5 was increased to 10 mL.

[0056] This experiment resulted in filter membrane blockage due to the increased amount of polyvinyl alcohol, and the mixed slurry solution was not completely filtered, making it impossible to prepare a complete fluorinated graphene film, which is not conducive to the preparation of fluorinated graphene films with multiple effects and the improvement of the electrochemical performance of the battery.

[0057] Comparative Example One

[0058] In this comparative example, no metal salt solution and reducing agent were added for the experiment, and the fluorinated graphene film prepared had a fluorine content of 55%, a metal particle doping amount of 0 wt%, and an active material surface loading of 5.08 mg / cm 2 The maximum discharge rate of the battery was 1C.

[0059] The fluorine content of the fluorinated graphene film prepared in this experiment did not decrease, and the metal particle content was 0 wt%. The hydrophilicity of the fluorinated graphene film was not improved, and the electrode conductivity was poor, which is not conducive to the preparation of fluorinated graphene films with multiple effects and the improvement of the electrochemical performance of the battery.

[0060] Comparative Example Two

[0061] In this comparative example, no carbon nanotubes were added for the experiment, and the fluorinated graphene film prepared had a fluorine content of 42%, a metal particle doping amount of 10.60 wt%, and an active material surface loading of 5.24 mg / cm 2 The maximum discharge rate of the battery was 2C.

[0062] In this experiment, no one-dimensional conductive material of carbon nanotubes was added to the prepared fluorinated graphene film, the transmission path of ions / electrons was reduced, and the conductivity of the electrode was not significantly improved, which is not conducive to the preparation of fluorinated graphene films with multiple effects and the improvement of the electrochemical performance of the battery.

[0063] Comparative Example Three

[0064] Comparative Example Three is the same as Example One, except that no polyvinyl alcohol aqueous solution is added in Step 4.

[0065] This experiment cannot prepare a fluorinated graphene film with a self-supporting structure. The fluorinated graphene film after drying cracks and cannot form a film, which is not conducive to preparing a fluorinated graphene film with multiple effects and improving the electrochemical performance of the battery.

[0066] Comparative Example Four

[0067] Comparative Example Four is the same as Example One, except that no carbon nanotubes, metal salt solution, and reducing agent are added. The fluorinated graphene film prepared has a fluorine content of 55%, a metal particle doping amount of 0 wt%, and an active material surface loading of 4.66 mg / cm 2 , and the maximum discharge rate of the battery is 0.1C.

[0068] The fluorinated graphene film prepared in this experiment lacks carbon nanotubes and conductive metal particles, the ion / electron transmission path is reduced, and the conductivity of the electrode is not significantly improved, which is not conducive to preparing a fluorinated graphene film with multiple effects and improving the electrochemical performance of the battery.

[0069] Comparative Example Five

[0070] Comparative Example Five is the same as Example One, except that the tap density of the fluorinated graphene positive electrode material is 0.04-0.05 g / cm 3 , the fluorine content is 55%, and the electrode is prepared by a traditional slurry coating method. Fluorinated graphene, Ketjen black, and polyvinylidene fluoride are weighed in a ratio of 8:1:1, respectively. The polyvinylidene fluoride is placed in a small beaker and a certain amount of N-methyl pyrrolidone is added and stirred into a gel-like substance. The surface high-conductivity fluorinated carbon and conductive Ketjen black are mixed uniformly and slowly added to the beaker. An appropriate amount of N-methyl pyrrolidone is added until a uniformly dispersed slurry is obtained, which is then coated on the carbon-coated aluminum foil at a thickness of 150 pm. The electrode sheet is prepared after vacuum drying for 10 h. The active material surface loading is 2.01 mg / cm 2 , and the maximum discharge rate performance of the battery is 3C.

[0071] Comparative Example Six

[0072] Comparative Example Six is the same as Comparative Example Five in terms of preparation method, both of which are traditional slurry coating methods. When the active material surface loading of the fluorinated graphene is >2.01 mg / cm 2 , the slurry layer of the electrode will crack and fall off during the drying process, which cannot improve the active material surface loading.

[0073] Refer to Tables 1 and 2 for a comparative summary of the effects of the mass ratio of fluorinated graphene to carbon nanotubes, reaction solution concentration, and reaction time on fluorine content, metal particle doping amount, active material surface loading, water contact angle, and discharge rate in the embodiments of the present invention. It can be seen that:

[0074] (1) See Figure 5 In Example 1, the mass ratio of fluorinated graphene to carbon nanotubes was 4:1, the concentration of the reaction solution was 200 mmol / L, the reaction time was 25 min, and the amount of polyvinyl alcohol aqueous solution added was 1 mL. The fluorinated graphene film prepared was the optimal parameter fluorinated graphene film, with a fluorine content of 35% and a metal particle doping amount of 12.04%. It was then installed as a lithium primary coin cell battery, and the maximum discharge rate of the battery was 8C.

[0075] (2) A comparison of Examples 1, 2, 3, 6, and 7 with Comparative Example 1 shows that the concentration of the reaction solution and the reaction time have the greatest impact on the fluorine content, metal particle doping amount, and battery discharge rate of the fluorinated graphene film, while having a smaller impact on its active material areal loading. Different reaction solution concentrations and reaction times result in different defluorination effects of the fluorinated graphene. A decrease in fluorine content can improve the hydrophilicity of the fluorinated graphene. Hydrophilicity (<90°) can be determined by the contact angle between the fluorinated graphene film and water. See [link to relevant documentation]. Figure 3 In Example 1, the water contact angle was 60.2°. After comprehensive comparison, the concentration of the reaction solution and the reaction time in Example 1 were found to be the optimal parameters.

[0076] (3) By comparing Examples 1, 4, and 5 with Comparative Example 2, it can be concluded that the proportion of carbon nanotubes has the greatest impact on the areal loading of active material in fluorinated graphene film and the discharge rate of battery. If there are no carbon nanotubes in the electrode, a conductive network structure cannot be formed, and the conductivity is reduced. When the content of carbon nanotubes is too high, they agglomerate and become severely entangled, which reduces the conductivity of fluorinated graphene film. In addition, carbon nanotubes have high hardness, and if the content exceeds a certain value, the electrode will be prone to brittle fracture and will occupy part of the mass of fluorinated graphene film. Furthermore, the increase in areal loading of active material is not significant. After comparison, it is concluded that the optimal parameter in Example 1 is the ratio of fluorinated graphene to carbon nanotubes of 4:1.

[0077] (4) See Figure 1 A comparison of Examples 1 and 8 with Comparative Example 3 shows that the amount of polyvinyl alcohol (PVA) added affects the formation of the electrode's self-supporting structure. Neither adding PVA aqueous solution nor adding 10 mL results in the inability to prepare a fluorinated graphene film, affecting its integrity. However, adding 1 mL of PVA in Example 1 not only prepares a complete fluorinated graphene film but also provides a certain degree of flexibility. This indicates that the amount of PVA added affects the integrity of the prepared fluorinated graphene film.

[0078] (5) See Figure 4, by comparing the infrared spectrum of Example 1 with that of fluorinated graphene material, the hydroxyl peak vibration of Example 1 is significantly enhanced and blue shifted to 3404 cm -1 , and the peak is wider, indicating that the added polyvinyl alcohol has abundant hydroxyl groups and hydrogen bonds are formed between the groups.

[0079] (6) Referring to Figure 2 and Table 3, by comparing Example 1 with Comparative Example 4, the fluorinated graphene in Example 1 has a connected three-dimensional conductive network structure due to the addition of carbon nanotubes and metal particles, which improves the conductivity of the fluorinated graphene film and effectively reduces the voltage hysteresis, further improving the maximum discharge rate of the battery.

[0080] (7) By comparing Example 1 with Comparative Examples 5 and 6, the fluorinated graphene with low tap density characteristics has poor rate performance when the face loading of the electrode prepared by the traditional sizing coating method is slightly increased, and the sizing coating method cannot prepare a perfect fluorinated graphene electrode when the active material face loading is further increased.

[0081]

[0082] Table 1

[0083]

[0084] Table 2

[0085]

[0086] Table 3

[0087] In summary, the example of the present application provides a preparation method of a fluorinated graphene film and a battery. The fluorinated graphene is mixed with carbon nanotubes and soaked in a mixed solution of anhydrous ethanol and deionized water, a reducing defluorination solution and a polyvinyl alcohol aqueous solution are added, vacuum filtration is performed, the filter membrane is peeled off after drying, and a fluorinated graphene film is obtained. The fluorinated graphene film has a fluorine content of 33-45%, a metal particle doping amount of 7.45-16.7wt%, and an active material loading of 3.32-5.24 mg / cm 2 , and the maximum discharge rate of the battery can reach 8C. The method is a one-step continuous process, which reduces the fluorine content of the fluorinated graphene by reducing defluorination, improves the hydrophilicity of the fluorinated graphene, and the conductive metal layer constructed by the reduced metal particles improves the conductivity; and the conductive metal particles, carbon nanotubes and fluorinated graphene are in contact with each other by using polyvinyl alcohol as an interlayer adhesive, a stable self-supporting three-dimensional conductive network structure is constructed, the active material face loading of the electrode is further improved, the transmission path of ions / electrons is shortened, the polarization during discharge is reduced, and the application of lithium / fluorinated carbon battery in high-power electronic devices is realized.

[0088] The above merely provides the preferred embodiments of the application, and not intended to limit the protection scope of the application. Any modification, equivalent replacement, and improvement made within the spirit and principle of the application shall fall within the protection scope of the application.

Claims

1. A method for producing a fluorinated graphene film, characterized by, The method comprises: The fluorinated graphene and carbon nanotubes are mixed and infiltrated in a mixed solution of anhydrous ethanol and deionized water, a reduction defluorination mixed solution is added, and defluorination of the fluorinated graphene and reduction of the conductive metal particles are performed; wherein the reduction defluorination mixed solution is composed of a metal salt solution and a reducing agent; A polyvinyl alcohol aqueous solution with hydroxyl groups and hydrogen bonds formed between the groups is added as a binder, ultrasonic dispersion is performed, vacuum filtration is performed, and the filter membrane is peeled off after drying to obtain a fluorinated graphene membrane; wherein the fluorine content of the fluorinated graphene membrane is 33-45%, the metal particle doping amount is 7.45-16.7wt%, and the active substance surface load is 3.32-5.24 mg / cm 2 , and the mass ratio of the fluorinated graphene to the carbon nanotube is 1-5:

1.

2. The method for producing a fluorinated graphene film according to claim 1, wherein The method further comprises: (1) The fluorinated graphene and carbon nanotubes are infiltrated in an anhydrous ethanol solution, stirred for 10 min, then ultrasonically treated for 30 min, washed with alcohol to remove impurities, and then infiltrated in deionized water and anhydrous ethanol to form a first mixed solution; (2) The first mixed solution is added to a sensitization solution in a volume ratio of 1:9 for sensitization for 1 h, washed to remove impurities, and then infiltrated in deionized water and anhydrous ethanol to form a second mixed solution; (3) The second mixed solution is added to 90 mL of the reduction defluorination mixed solution in one step and reacted for 10-40 min, wherein the volume ratio of the metal salt solution and the reducing agent in the reduction defluorination mixed solution is 3:1; 1 mL of a polyvinyl alcohol aqueous solution is added dropwise to the solution at the end of the reaction, ultrasonically treated for 10 min, then vacuum filtered, and washed with deionized water and anhydrous ethanol alternately for three times; wherein the polyvinyl alcohol aqueous solution is prepared by dissolving polyvinyl alcohol powder in deionized water at 95 ℃; (4) The obtained film sample is dried, the filter membrane is peeled off, and a fluorinated graphene film is obtained.

3. The method for preparing a fluorinated graphene film according to claim 2, characterized in that, The tap density of the fluorinated graphene is 0.04~0.05 g / cm 3 , and the fluorine content is 50~60%.

4. The method of claim 2, wherein the fluorinated graphene film is prepared by a process comprising: (a) providing a graphene film; (b) exposing the graphene film to a fluorine-containing gas; and (c) annealing the graphene film. The carbon nanotubes include at least one of multi-walled carbon nanotubes, single-walled carbon nanotubes, carbon nanowires, carbon nanotube bundles, and snake-shaped carbon nanotubes, and the concentration of the first mixed solution is 5-10 mg / mL.

5. The method for producing a fluorinated graphene film according to claim 2, characterized by, The sensitization solution is prepared by dissolving stannous chloride solid and hydrochloric acid solution in deionized water and anhydrous ethanol in a volume ratio of 1:

1.

6. The method for producing a fluorinated graphene film according to claim 2, characterized by, The reducing agent includes at least one of a combination of glucose and sodium citrate, hydrazine, formaldehyde, and dimethylaminoborane.

7. The method of claim 2, wherein the fluorinated graphene film is prepared by a process comprising: The metal salt includes at least one of nitrate, chloride, and sulfate, and the conductive metal particles are Ag.

8. The method for producing a fluorinated graphene film according to claim 2, characterized by, The molecular weight of the polyvinyl alcohol ranges from 120000 to 150000.

9. The method for producing a fluorinated graphene film according to claim 2, characterized by, The filter membrane includes at least one of a polytetrafluoroethylene membrane, a polyamide membrane, and a glass fiber membrane.

10. A battery, characterized by The fluorinated graphene film obtained by the preparation method of any one of claims 1-9 is included.

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