Conductive fiber for capacitor, electrode material and preparation method
The preparation of conductive fibers by aqueous phase in-situ polymerization has solved the problems of high cost and low retention of conductive active substances in the prior art, and achieved efficient conductive effects and electrochemical properties, which are suitable for flexible wearable devices.
Patent Information
- Application Number
- CN202510413044.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-02
- Publication Date
- 2025-07-22
AI Technical Summary
The existing conductive active substances such as carbon nanotubes, graphene and MXene materials are costly and difficult to produce in industrial production. The retention rate of conductive active substances in flexible electrode materials is low, the preparation efficiency of impregnation method is low and the cost is high, and the preparation cost of nanocellulose is high and the difficulty of filtration of water is high.
Conductive fibers were prepared by aqueous phase in situ polymerization. By adding sodium hydroxide and 2,3-epoxypropyl trimethylammonium chloride to the needle wood pulp for etherification, cationic nanofibers were prepared and mixed with non-wood fibers. The aqueous phase in situ polymerization was used to deposit and grow polypyrrole on the mixed fibers, and the bond was tightly combined to avoid the problem of impregnation liquid recovery and achieve industrial continuous production.
The conductive fibers are closely combined with the fibers, reducing the difficulty of preparation, improving the conductive effect and the electrochemical performance of the electrode materials, and are suitable for flexible wearable devices.
Smart Images
Figure CN120356785A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of conductive materials, and specifically, to a conductive fiber, an electrode material and a preparation method for a capacitor. Background Art
[0002] Supercapacitors (also known as electrochemical capacitors) have become a research focus in the field of energy storage due to their high power density, fast charge and discharge performance, and long cycle life. As one of the conductive active substances, conductive polymers have attracted extensive attention due to their unique one-dimensional conjugated structure, low cost, and good electrical and electrochemical properties. Among these polymers, polypyrrole (PPy) has high conductivity and is highly flexible in terms of electrochemical properties compared with other conductive polymers, and has a specific capacitance comparable to that of transition metal oxide-based pseudocapacitive electrodes. Therefore, PPy has been widely studied as a pseudocapacitive electrode material.
[0003] With the rapid development of wearable devices and flexible electronics, the demand for flexible wearable supercapacitors is increasing continuously. Therefore, manufacturing flexible supercapacitors remains a great challenge, especially for flexible electrodes with good mechanical properties and electrochemical properties. Cellulose fibers are widely used as the substrate of flexible electrode materials due to their rich reserves, environmental friendliness, good mechanical properties and flexibility, and are ideal materials to replace petroleum-based materials in the fields of electronics and energy storage.
[0004] Cationic Cellulose Nanofibers (CCNF) are modified nanofibers obtained by combining cellulose with cationic reagents through physical or chemical methods. The positive charges carried by itself can adsorb negatively charged substances in the system, and are widely used in the fields of papermaking industry, wastewater treatment, biomedicine, etc.
[0005] Currently, most of the used conductive active substances (such as carbon nanotubes, graphene, MXene materials, etc.) have high costs, great difficulty in industrial production itself, and low retention rate of the conductive active substances in the produced flexible electrode materials; the flexible electrodes prepared by the impregnation method require multiple impregnations, with low preparation efficiency, and great difficulty and high cost in recovering the impregnating solution; preparing flexible electrodes using nanofibers as the substrate has problems such as great difficulty in water filtration and high preparation cost of nanofibers.
[0006] In view of this, the present application is proposed. Summary of the Invention
[0007] The purpose of the present application is to provide a conductive fiber, an electrode material and a preparation method for a capacitor, so as to solve at least one technical problem mentioned in the background art.
[0008] Specifically, in the first aspect of the present application, a method for preparing conductive fibers for capacitors is provided, including the steps:
[0009] Step for preparing cationic nanofibers: Add sodium hydroxide to softwood pulp to make the concentration of sodium hydroxide in the pulp suspension 3 - 10%, stir for 1 - 2.5 h, add 2,3-epoxypropyltrimethylammonium chloride with a mass ratio to the oven-dry pulp of 3 - 5:1 for etherification reaction, with the reaction temperature at 40 - 50 °C and the reaction time at 4 - 6 h; wash, filter and grind the reacted fibers.
[0010] Step for preparing conductive fibers: Take non-wood fibers and make their beating degree 40 - 65 °SR and the pulp concentration 0.8 - 1.5%, mix the beaten non-wood fibers with cationic nanofibers to obtain mixed fibers, where the mass of the cationic nanofibers is 2.5 - 10% of the mixed fibers; use the method of in-situ polymerization in aqueous phase to deposit and grow polypyrrole on the mixed fibers.
[0011] By adopting the above technical solution, through the in-situ polymerization method in aqueous phase, polypyrrole is more tightly combined with the fibers and is not easy to fall off, which can avoid the problem that the impregnating solution cannot be recycled brought by the impregnation method, reduce the preparation difficulty, directly endow the fibers with conductivity, and is easy to realize industrial continuous production.
[0012] Preferably, the capacitor is a supercapacitor. Preferably, in the step for preparing cationic nanofibers, the pulp concentration of the softwood pulp is 0.5 - 2%, and more preferably, the pulp concentration of the softwood pulp is 1%.
[0013] Preferably, in the step for preparing cationic nanofibers, the concentration of sodium hydroxide in the pulp suspension is 4 - 8%.
[0014] Preferably, in the step for preparing cationic nanofibers, the reaction time of the etherification reaction is 5 h.
[0015] Preferably, in the step for preparing cationic nanofibers, after the reacted fibers are washed and filtered, they are ground in a nano-grinder for 3 - 5 h, preferably 4 h.
[0016] Preferably, in the step for preparing conductive fibers, the dosage of pyrrole is 70 - 90% relative to the oven-dry fibers of the mixed fibers, the oxidant for the pyrrole polymerization reaction is ferric chloride, the molar ratio of pyrrole to ferric chloride is 1:1 - 3, the polymerization reaction time is 1 - 3 h, and the reaction temperature is 0 - 10 °C. More preferably, the molar ratio of pyrrole to ferric chloride is 1:2.
[0017] Preferably, the non-wood fibers are bamboo pulp fibers and / or Chinese alpine rush pulp fibers.
[0018] In a second aspect of the present application, a method for preparing an electrode material is provided, including the steps of:
[0019] Preparing conductive fibers by the method of the first aspect of the present application;
[0020] Steps for preparing the electrode material: forming, pressing, and drying the conductive fibers by wet papermaking process to obtain a flexible electrode material, with a pressing pressure of 0.3 - 0.8 MPa and a drying temperature of 75 - 95 °C.
[0021] In a third aspect of the present application, an electrode material is provided, which is obtained by the method for preparing the electrode material described in the third aspect of the present application.
[0022] Preferably, the conductivity of the electrode material is 5.73 - 6.04 S / cm, and the specific capacitance is 1836.12 - 1964.14 mF cm -2 .
[0023] In summary, the present application has the following beneficial effects:
[0024] 1. The method for preparing conductive fibers provided by the present application, through the in-situ polymerization method in aqueous phase, makes the polypyrrole combine more tightly with the fibers and is not easy to fall off, can avoid the problem that the impregnating solution cannot be recycled brought by the impregnation method, reduces the preparation difficulty, directly endows the fibers with conductivity, and is easy to realize industrial continuous production.
[0025] 2. The method for preparing conductive fibers provided by the present application, by adding cationic nanofibers to prepare mixed fibers, compared with conventional plant fibers, because the cationic nanofibers in the mixed fibers can provide more loading sites for the polymerization of pyrrole, is more conducive to the formation of a conductive network, and makes its conductive effect better.
[0026] 3. The method for preparing conductive fibers provided by the present application, the cyclic voltammetry (CV) curve of the obtained electrode material shows good symmetry and presents a quasi-rectangular or spindle shape, indicating its pseudocapacitance performance and good electrochemical reversible behavior, making the electrode material have good electrochemical characteristics. Description of the Drawings
[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0028] Figure 1 It is a photo of the electrode material obtained in Example 1 of the present application;
[0029] Figure 2 A photograph showing the flexibility of the electrode material in Example 1 of the present application;
[0030] Figure 3 A photograph showing the electrical conductivity of the electrode material in Example 1 of the present application;
[0031] Figure 4 The cyclic voltammetry curves of Example 1 of the present application at different scanning rates. Detailed implementation manners
[0032] The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.
[0033] The terms used in the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "the", and "said" used in the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any and all possible combinations of one or more of the associated listed items.
[0034] The present application will be described in detail below through examples.
[0035] In the prior art, the commonly used conductive active substances (such as carbon nanotubes, graphene, MXene materials, etc.) have high costs, great difficulty in industrial production itself, and low retention rates of conductive active substances in the produced flexible electrode materials; the flexible electrodes prepared by the impregnation method require multiple impregnations, with low preparation efficiency, and great difficulty and high cost in recovering the impregnating solution; preparing flexible electrodes using nanocellulose as the substrate has problems such as great difficulty in water filtration and high preparation costs of nanocellulose. Therefore, there is an urgent need in the art for a new type of conductive material to solve the above technical problems.
[0036] In view of this, to solve the technical problems existing in the background art, the inventive concept of the present application is to provide a method for preparing conductive fibers for capacitors, including the steps: a cationic nanofiber preparation step, adding sodium hydroxide to softwood pulp to make the concentration of sodium hydroxide in the pulp suspension 3-10%, stirring for 0.5-3 h, adding 2,3-epoxypropyltrimethylammonium chloride with a mass ratio of 2-6:1 to the absolute dry pulp for etherification reaction, the reaction temperature is 35-55 °C, and the reaction time is 4-6 h; washing, filtering and grinding the reacted fibers. A conductive fiber preparation step, taking non-wood fibers and making their beating degree 35-80 °SR, the pulp concentration is 0.3-2.0%, mixing the beaten non-wood fibers with cationic nanofibers to obtain mixed fibers, and the mass of the cationic nanofibers is 2.5-15% of the mixed fibers; using the method of in-situ polymerization in aqueous phase to deposit and grow polypyrrole on the mixed fibers.
[0037] According to this inventive concept, through the in-situ polymerization method in aqueous phase, polypyrrole is more tightly combined with the fibers and is not easy to fall off, which can avoid the problem that the impregnating solution cannot be recovered caused by the impregnation method, reduce the preparation difficulty, directly endow the fibers with conductivity, and is easy to realize industrial continuous production.
[0038] To better understand the above technical solutions, the following will describe the above technical solutions in detail in combination with specific embodiments. Those skilled in the art should also understand that the reaction time and component feeding involved in the present application cannot be absolutely accurate in the actual production process, but are within the allowable error range. For example, if it is desired to heat the sample for 30 minutes, the actual operation may be 1 second more or less than 30 minutes; if it is desired to weigh 30 g of the sample, the actual weight may be 30.001 g or 29.998 g.
[0039] Unless otherwise specified, all raw materials involved in the present application are commercially available products.
[0040] Example 1
[0041] Preparation of cationic nanofibers: Add sodium hydroxide to softwood pulp with a pulp concentration of 1.0% to make the concentration of sodium hydroxide in the pulp suspension 5%, stir for 2 h, add 2,3-epoxypropyltrimethylammonium chloride in a mass ratio of 3:1 to the absolute dry pulp for etherification reaction, the reaction temperature is 45 °C, and the reaction time is 5 h. Wash, filter the reacted fibers into a nano grinder and grind for 4 h.
[0042] Preparation of conductive fiber: The fiber is a mixed fiber of bamboo pulp fiber and cationic nanofiber. The beating degree of the bamboo pulp fiber is 50°SR, the pulp concentration is 1.0%, and the dosage of the cationic nanofiber is 5% based on the absolute dry fiber of the mixed fiber. The method of in-situ polymerization in aqueous phase is used to deposit and grow polypyrrole on the fiber. The dosage of pyrrole is 70% based on the absolute dry fiber, the oxidant for the pyrrole polymerization reaction is ferric chloride, the molar ratio of pyrrole to ferric chloride is 1:2, the polymerization reaction time is 2 h, and the reaction temperature is 4°C.
[0043] Preparation of electrode material: The above conductive fiber is formed, pressed, and dried by the wet papermaking process to obtain a flexible electrode material. The pressing pressure is 0.3 MPa, and the drying temperature is 95°C.
[0044] After testing, the basis weight of the flexible electrode material is 90 g / m 2 , the conductivity is 6.04 S / cm, and the specific capacitance is 1964.14 mF cm -2 (current density 5 mA cm -2 ).
[0045] Example 2
[0046] Preparation of cationic nanofiber: Sodium hydroxide is added to softwood pulp with a pulp concentration of 1.0% to make the concentration of sodium hydroxide in the pulp suspension 8%. Stir for 1.5 h, and add 2,3-epoxypropyltrimethylammonium chloride in a mass ratio of 5:1 to the absolute dry pulp for etherification reaction. The reaction temperature is 40°C, and the reaction time is 5 h. Wash and filter the reacted fiber into a nano grinder and grind for 4 h.
[0047] Preparation of conductive fiber: The fiber is a mixed fiber of bamboo pulp fiber and cationic nanofiber. The beating degree of the bamboo pulp fiber is 65°SR, the pulp concentration is 1.5%, and the dosage of the cationic nanofiber is 2.5% based on the absolute dry fiber of the mixed fiber. The method of in-situ polymerization in aqueous phase is used to deposit and grow polypyrrole on the fiber. The dosage of pyrrole is 70% based on the absolute dry fiber, the oxidant for the pyrrole polymerization reaction is ferric chloride, the molar ratio of pyrrole to ferric chloride is 1:2, the polymerization reaction time is 3 h, and the reaction temperature is 6°C.
[0048] Preparation of electrode material: The above conductive fiber is formed, pressed, and dried by the wet papermaking process to obtain a flexible electrode material. The pressing pressure is 0.5 MPa, and the drying temperature is 75°C.
[0049] After testing, the basis weight of the flexible electrode material is 90 g / m 2 , the conductivity is 5.73 S / cm, and the specific capacitance is 1868.69 mF cm -2 (current density 5 mA cm -2 ).
[0050] Example 3
[0051] Preparation of cationic nanofibers: Sodium hydroxide was added to softwood pulp with a consistency of 1.0%, so that the concentration of sodium hydroxide in the pulp suspension was 4%. Stir for 2.5 h, and add 2,3-epoxypropyltrimethylammonium chloride in a mass ratio of 3:1 to the absolute dry pulp for etherification reaction. The reaction temperature was 50 °C and the reaction time was 5 h. The reacted fibers were washed, filtered and ground in a nano grinder for 4 h.
[0052] Preparation of conductive fibers: The fibers were a mixed fiber of bamboo pulp fibers and cationic nanofibers. The beating degree of the bamboo pulp fibers was 40°SR, the pulp consistency was 0.8%, and the dosage of cationic nanofibers was 10% relative to the absolute dry fibers of the mixed fibers. The method of in-situ polymerization in aqueous phase was used to deposit and grow polypyrrole on the fibers. The dosage of pyrrole was 90% relative to the absolute dry fibers. The oxidant for the pyrrole polymerization reaction was ferric chloride. The molar ratio of pyrrole to ferric chloride was 1:2. The polymerization reaction time was 1.5 h and the reaction temperature was 3 °C.
[0053] Preparation of electrode materials: The above conductive fibers were formed, pressed and dried by the wet papermaking process to obtain a flexible electrode material. The pressing pressure was 0.6 MPa and the drying temperature was 80 °C.
[0054] The basis weight of the flexible electrode material was 90 g / m 2 , the conductivity was 5.95 S / cm, and the specific capacitance was 1836.12 mF cm -2 (current density 5 mA cm -2 ).
[0055] Example 4
[0056] Preparation of cationic nanofibers: Sodium hydroxide was added to softwood pulp with a consistency of 1.0%, so that the concentration of sodium hydroxide in the pulp suspension was 6%. Stir for 1 h, and add 2,3-epoxypropyltrimethylammonium chloride in a mass ratio of 3.5:1 to the absolute dry pulp for etherification reaction. The reaction temperature was 40 °C and the reaction time was 5 h. The reacted fibers were washed, filtered and ground in a nano grinder for 4 h.
[0057] Preparation of conductive fibers: The fibers were a mixed fiber of Chinese alpine rush pulp fibers and cationic nanofibers. The beating degree of the Chinese alpine rush pulp fibers was 55°SR, the pulp consistency was 1.0%, and the dosage of cationic nanofibers was 7.5% relative to the absolute dry fibers of the mixed fibers. The method of in-situ polymerization in aqueous phase was used to deposit and grow polypyrrole on the fibers. The dosage of pyrrole was 80% relative to the absolute dry fibers. The oxidant for the pyrrole polymerization reaction was ferric chloride. The molar ratio of pyrrole to ferric chloride was 1:2. The polymerization reaction time was 2.5 h and the reaction temperature was 5 °C.
[0058] Preparation of the electrode material: The above conductive fibers were formed, pressed, and dried using the wet papermaking process to obtain a flexible electrode material. The pressing pressure was 0.8 MPa, and the drying temperature was 75 °C.
[0059] The basis weight of the flexible electrode material was 90 g / m 2 , the conductivity was 6.01 S / cm, and the specific capacitance was 1850.19 mF cm -2 (at a current density of 5 mA cm -2 ).
[0060] Comparative Example 1
[0061] Preparation of the conductive fibers: The fibers were a mixed fiber of softwood pulp fibers and nanofibers (CNF). The beating degree of the bamboo pulp fibers was 50 °SR, the pulp consistency was 1.0%, the CNF was nanocellulose prepared by a mechanical method, and the CNF dosage was 5% relative to the oven-dry fibers. The polypyrrole was deposited and grown on the fibers by the method of in-situ polymerization in an aqueous phase. The pyrrole dosage was 70% relative to the oven-dry fibers. The oxidant for the pyrrole polymerization reaction was ferric chloride, the molar ratio of pyrrole to ferric chloride was 1:2, the polymerization reaction time was 2 h, and the reaction temperature was 4 °C.
[0062] Preparation of the electrode material: The above conductive fibers were formed, pressed, and dried using the wet papermaking process to obtain a flexible electrode material. The pressing pressure was 0.3 MPa, and the drying temperature was 95 °C.
[0063] The basis weight of the flexible electrode material was 90 g / m 2 , the conductivity was 5.01 S / cm, and the specific capacitance was 1687.46 mF cm -2 (equivalent to a current density of 5 mA cm -2 ).
[0064] Comparative Example 2
[0065] Preparation of the conductive fibers: The fibers were bamboo pulp fibers. The beating degree of the bamboo pulp fibers was 50 °SR, and the pulp consistency was 1.0%. The polypyrrole was deposited and grown on the fibers by the method of in-situ polymerization in an aqueous phase. The pyrrole dosage was 70% relative to the oven-dry fibers. The oxidant for the pyrrole polymerization reaction was ferric chloride, the molar ratio of pyrrole to ferric chloride was 1:2, the polymerization reaction time was 2 h, and the reaction temperature was 4 °C.
[0066] Preparation of the electrode material: The above conductive fibers were formed, pressed, and dried using the wet papermaking process to obtain a flexible electrode material. The pressing pressure was 0.3 MPa, and the drying temperature was 95 °C.
[0067] The basis weight of the flexible electrode material was 90 g / m 2 , the conductivity was 4.55 S / cm, and the specific capacitance was 686.97 mF cm -2(Equivalent to a current density of 5 mA cm -2 ).
[0068] According to the above Examples 1-4 and Comparative Examples 1-2, those skilled in the art can understand:
[0069] First, comparing Examples 1-4 with Comparative Example 1, when preparing hybrid fibers with the cationic nanofibers obtained by the preparation method of the present application, compared with conventional nanofibers, due to the addition of cationic nanofibers in the hybrid fibers, it is more suitable for the deposition and growth of polypyrrole, and can enable the final product electrode material to obtain higher conductivity and specific capacitance, making its conductive effect better;
[0070] Second, comparing Examples 1-4 with Comparative Example 2, when preparing hybrid fibers with the cationic nanofibers obtained by the preparation method of the present application, compared with non-wood fibers such as bamboo pulp fibers, it can provide more loading sites for the polymerization of pyrrole, is more conducive to the formation of a conductive network, and has a better conductive effect;
[0071] Third, cationic nanocellulose has a high aspect ratio and carries a positive charge, which can make pyrrole polymerize better on the fibers through electrostatic attraction, while improving the compactness of the conductive network, being conducive to charge transport, and enhancing the physical strength of the conductive material.
[0072] Furthermore, according to Figures 1 - 4 , those skilled in the art can understand:
[0073] First, the electrode material provided by the present application has good flexibility and can meet wearable devices in different scenarios;
[0074] Second, the electrode material provided by the present application has good conductivity and can make the light-emitting diode in the circuit emit light;
[0075] Third, the cyclic voltammetry CV curve of the electrode material provided by the present application shows good symmetry and presents a quasi-rectangle (or spindle shape), which indicates that it has pseudocapacitance performance and good electrochemical reversible behavior, which is attributed to the doping-dedoping reversible process of polypyrrole, making the electrode material have good electrochemical characteristics.
[0076] In summary, the present invention uses the aqueous phase in-situ polymerization method, in which polypyrrole and the fiber are tightly combined and not easy to fall off, can avoid the problem that the impregnating solution cannot be recycled brought by the impregnation method, reduce the preparation difficulty, directly endow the fiber with conductivity, and is easy to realize industrial continuous production.
[0077] It should be noted that for those of ordinary skill in the art, the technical features in the above embodiments can be freely combined, and the formed technical solutions also belong to the embodiments disclosed in the present application.
[0078] Furthermore, without departing from the principle of the present application, several improvements and modifications can also be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.
Claims
1. A preparation method of conductive fibers for capacitors, characterized in that: It includes the steps: Cationic nanofiber preparation step: Add sodium hydroxide to softwood pulp to make the concentration of sodium hydroxide in the pulp suspension 3-10%, stir for 1-2.5 h, add 2,3-epoxypropyltrimethylammonium chloride with a mass ratio of 3-5:1 to the absolute dry pulp for etherification reaction, the reaction temperature is 40-50 °C, and the reaction time is 4-6 h; Wash, filter and grind the reacted fibers; Conductive fiber preparation step: Take non-wood fibers and make their beating degree 40-65°SR, and the pulp concentration is 0.8-1.5%. Mix the beaten non-wood fibers with cationic nanofibers to obtain mixed fibers, and the mass of the cationic nanofibers is 2.5-10% of the mixed fibers; Use the method of in-situ polymerization in aqueous phase to deposit and grow polypyrrole on the mixed fibers.
2. The preparation method of conductive fibers for capacitors according to claim 1, characterized in that: In the cationic nanofiber preparation step, the pulp concentration of the softwood pulp is 0.5-2%.
3. The preparation method of conductive fibers for capacitors according to claim 1, characterized in that: In the cationic nanofiber preparation step, the concentration of sodium hydroxide in the pulp suspension is 4-8%.
4. The preparation method of conductive fibers for capacitors according to claim 1, characterized in that: In the cationic nanofiber preparation step, the reaction time of the etherification reaction is 5 h.
5. The preparation method of conductive fibers for capacitors according to claim 1, characterized in that: In the cationic nanofiber preparation step, after the reacted fibers are washed and filtered, they are ground in a nano grinder for 3-5 h.
6. The preparation method of conductive fibers for capacitors according to claim 1, characterized in that: In the conductive fiber preparation step, the dosage of pyrrole is 70-90% relative to the absolute dry fiber of the mixed fibers, the oxidant for the pyrrole polymerization reaction is ferric chloride, the molar ratio of pyrrole to ferric chloride is 1:1-3, the polymerization reaction time is 1-3 h, and the reaction temperature is 0-10 °C.
7. The preparation method of conductive fibers for capacitors according to any one of claims 1-6, characterized in that: The non-wood fibers are bamboo pulp fibers and / or Chinese alpine rush pulp fibers.
8. A preparation method of an electrode material, including the steps: Prepare conductive fibers by the method according to any one of claims 1-7; Electrode material preparation step: Form, press and dry the conductive fibers by wet papermaking process to obtain a flexible electrode material, the pressing pressure is 0.3-0.8 MPa, and the drying temperature is 75-95 °C.
9. An electrode material prepared by the preparation method of the electrode material according to claim 8.
10. The electrode material according to claim 9, characterized in that: The conductivity of the electrode material is 5.73 - 6.04 S / cm, and the specific capacitance is 1836.12 - 1964.14 mF cm -2 .