A high-mold, high-strength, low-impedance all-solid-state lithium metal deposited carbon fiber structure battery

Abstract

The present invention provides a high-modulus, high-strength, low-impedance all-solid-state lithium metal-deposited carbon fiber integrated structure battery, comprising: a positive carbon fiber coated with an active material, insulating glass fiber, a negative carbon fiber deposited with lithium metal, a polymer electrolyte, ceramic electrolyte particles, inorganic lithium salt particles, and a structural resin; the positive carbon fiber coated with the active material is obtained by drying a carbon fiber coated with an active material slurry; the negative carbon fiber deposited with lithium metal is obtained by depositing lithium metal through a primary battery process; each layer is stacked in the order of the positive carbon fiber, the glass fiber, and the negative carbon fiber; in an anhydrous and oxygen-free environment, a solid electrolyte solution, ceramic electrolyte particles, inorganic lithium salt particles, and a structural resin liquid are mixed in a certain proportion to form a structural electrolyte, which is poured into a preform and cured by high-temperature pressing. The present invention realizes a low-impedance all-solid-state integrated carbon fiber structure battery, making full use of the electrical and mechanical properties of all materials.

Description

Technical Field

[0001] The present invention relates to the technical field of manufacturing multifunctional composite materials, and particularly to a high-modulus, high-strength, low-impedance all-solid-state lithium metal deposited carbon fiber structure battery. Background Art

[0002] Energy storage structures are a typical lightweight and high-performance structure that can store energy while providing structural strength, such as sandwich battery carbon fiber composites, wing fuel tanks, etc. With the continuous improvement of equipment service requirements, energy storage structures also need to be continuously improved to achieve higher energy storage capacity and better mechanical properties. Carbon fiber lithium metal structure batteries are currently the most advanced integrated structural energy storage advanced materials, and their reinforcement stacking structure is carbon fiber positive current collector - positive active material - insulating fiber separator - lithium metal - carbon fiber negative current collector, and the matrix region is filled with a mixture of electrolyte and structural resin. Due to the lightweight, high modulus, high strength, high conductivity, and high electrochemical capacity of carbon fiber, it can provide high-strength load support while acting as a battery current collector or reaction negative electrode, making it possible to have high mechanical property batteries.

[0003] Among them, the electrolyte that plays the role of ion channels can be divided into solid and liquid. The solid electrolyte with barely load transfer ability has extremely poor ion conductivity and extremely high impedance. Therefore, at present, in order to balance mechanical properties and ion transport ability, a method of mixing liquid electrolyte and structural resin is often used. However, the liquid electrolyte has no load-bearing capacity at all, and the flowing liquid also brings potential risks of damage and leakage during the forming and use processes of the structural battery. Therefore, it is of great significance to design an all-solid-state carbon fiber lithium metal structure battery with high mechanical properties and low impedance.

[0004] Patent document CN113036268A discloses a lithium metal structural battery with both structural support and electrochemical energy storage functions, belonging to the field of energy storage. The lithium metal structural battery of the present invention is composed of a structural cathode, a structural electrolyte, a lithium metal anode, a tab, and a fiber / epoxy composite encapsulation material. The lithium metal anode has taken protective treatment measures to ensure its stability during battery assembly. The structural electrolyte is composed of an inorganic electrolyte and a polymer electrolyte reinforced by glass fibers, and it has high mechanical properties and excellent ionic conduction ability. This patent proposes to use a glass fiber-reinforced solid electrolyte as the core layer separator membrane, and stack it in the order of encapsulation material - carbon fiber current collector - lithium metal foil - glass fiber-reinforced polymer solid electrolyte - positive electrode active material - carbon fiber current collector - encapsulation material. Since the mechanical properties of the polymer solid electrolyte are poor, it cannot effectively constrain the fibers, and the fibers are still in a soft buckling state. The mechanical properties still need to be provided by the fiber-reinforced epoxy encapsulation material, and it essentially still belongs to the battery embedded structure. Moreover, the lithium metal in the form of a foil will also hinder the resin infiltration and affect the mechanical properties of the structural battery as a delamination defect. The field still needs to propose a more advanced and effective high mechanical property and low impedance all-solid-state integrated carbon fiber lithium metal structural battery. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a high modulus, high strength, and low impedance all-solid-state lithium metal deposited carbon fiber structural battery.

[0006] The purpose of the present invention can be achieved through the following solutions:

[0007] The present invention provides a high modulus, high strength, and low impedance all-solid-state lithium metal deposited carbon fiber structural battery, including a positive electrode carbon fiber reinforcement containing active materials, insulating fibers, and a negative electrode carbon fiber reinforcement arranged in sequence. The three are wrapped as a whole in a structural electrolyte obtained by mixing a polymer electrolyte and a structural resin; a lithium metal layer is deposited on the surface of the negative electrode carbon fiber reinforcement, and an active material is coated on the surface of the positive electrode carbon fiber reinforcement.

[0008] Preferably, a silver-plated layer is coated on the surface of the negative electrode carbon fiber reinforcement and then the lithium metal layer is deposited.

[0009] Preferably, the structural electrolyte further includes ceramic electrolyte particles and inorganic lithium salts.

[0010] The present invention also provides a preparation method of a high modulus, high strength, and low impedance all-solid-state lithium metal deposited carbon fiber structural battery, including the following steps:

[0011] Step S1: Deposit a lithium metal layer on the carbon fiber surface to obtain the negative electrode carbon fiber reinforcement of the structural battery;

[0012] Step S2: Mix the conductive agent, binder, and active material, dissolve them in N-methylpyrrolidone (NMP), and stir to form a positive electrode slurry;

[0013] Step S3: Uniformly coat the positive electrode slurry obtained in Step S2 on the carbon fiber, and dry it at high temperature under vacuum to dry the N-methylpyrrolidone (NMP) and obtain a positive electrode carbon fiber reinforcement containing the active material;

[0014] Step S4: Sequentially lay the positive electrode current collector, the positive electrode carbon fiber reinforcement containing the active material, the insulating fiber, the negative electrode carbon fiber reinforcement, and the negative electrode current collector on the female die mold to obtain a preform;

[0015] Step S5: Under an anhydrous and anaerobic environment, dissolve lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) in an N-methylpyrrolidone (NMP) solution, and stir evenly to obtain a polymer electrolyte solution;

[0016] Step S6: Under an anhydrous and anaerobic environment, uniformly mix the polymer electrolyte solution obtained in Step S5 with the structural resin and the resin curing agent to obtain a structural electrolyte;

[0017] Step S7: Under an anhydrous and anaerobic environment, pour the structural electrolyte obtained in Step S6 into the preform obtained in Step S4 as a whole and heat it at high temperature for curing. After curing, seal the holes with the structural resin again to obtain the structural battery.

[0018] Preferably, in Steps S1 and S3, the carbon fiber is a desized carbon fiber. The desizing process is specifically as follows: The carbon fiber unidirectional tape is calcined in the air to obtain the desized carbon fiber.

[0019] Preferably, in Step S1, depositing the lithium metal layer is specifically as follows: Deposit a silver layer on the carbon fiber as the positive electrode, assemble it with the separator, the lithium metal negative electrode, and the electrolyte into a half-cell, perform constant current charge and discharge cycling. After several cycles, under an anhydrous and anaerobic environment, take out the carbon fiber with deposited lithium metal. The lithium metal deposition amount and deposition form of the carbon fiber with deposited lithium metal can be regulated. The greater the silver plating thickness and the longer the constant current charge and discharge time, the greater the deposition amount.

[0020] Preferably, the silver mirror reaction plating is used to deposit the silver layer, specifically as follows: Immerse the desized carbon fiber unidirectional tape in the SnCl2 solution; add a small amount of glucose to concentrated sulfuric acid and heat to dissolve it, then add the silver ammonia solution and KOH solution, immerse the carbon fiber unidirectional tape in it, and after taking it out, rinse the carbon fiber with deionized water to remove the residual solution to obtain it.

[0021] Preferably, in step S2, the active material includes one or more of ternary lithium metal oxide, lithium iron phosphate, lithium manganate, and lithium cobaltate. The ternary lithium metal oxide includes LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), LiNi 0.5 Co 0.2 Mn 0.3 O2 (NCM523), LiNi 0.3 Co 0.3 Mn 0.3 O2 (NCM111).

[0022] Preferably, in step S2, the mass ratio of the conductive agent: binder: active material is 1:1:7 - 1:2:8, preferably 1:1:8 or 1:2:7. After the three are mixed evenly, they are dissolved in N-methylpyrrolidone (NMP) at a mass-volume ratio of 0.1 - 0.3 g / ml. The type of conductive agent can be acetylene black or conductive carbon black Super P, and the binder can be polyvinylidene fluoride PVDF.

[0023] Preferably, the weaving form of the carbon fiber used in steps S1 and S3 includes one of unidirectional fabric, plain fabric, twill fabric, satin fabric, and three-dimensional woven fabric.

[0024] Preferably, in step S4, the positive electrode current collector is stainless steel foil or aluminum foil, and the negative electrode current collector is stainless steel foil or copper foil.

[0025] Preferably, in step S5, the mass ratio of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) to polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) is 1.5 - 2.5:3, preferably 2:3.

[0026] Preferably, in step S6, the resin curing agent includes ceramic electrolyte particles and inorganic lithium salt particles, which are ultrasonically dispersed in the resin curing agent. The ceramic electrolyte particles include Li 6.4 La3Zr 1.4 Ta 0.6 O 12 (LLZTO), Li 6.3 La3Zr 1.65 W 0.35 O 12 (LLZWO), Li7La3Zr2O 12 (LLZO), Li 6.75 La3Zr 1.75 Nb 0.25 O 12One or more of (LLZNO). The diameter of the ceramic electrolyte particles needs to be less than or equal to 500 nm. The inorganic lithium salt particles are LiF, and the particle diameter needs to be less than or equal to 500 nm. The total mass of the ceramic electrolyte particles and the inorganic lithium salt particles does not exceed 50% of polyvinylidene fluoride - hexafluoropropylene (PVDF - HFP) to avoid the particles not being fully wrapped by PVDF - HFP.

[0027] Preferably, in step S6, the structural resin material is one of epoxy resin, bismaleimide resin, and polyimide resin formed by liquid molding. The resin curing agent includes one of acid anhydrides and amines.

[0028] Preferably, in step S7, the temperature for high - temperature pressure curing is: 60 - 180 °C for epoxy resin; 180 - 250 °C for bismaleimide resin; 250 - 400 °C for polyimide resin. The curing time is 1 - 6 h, and the curing pressure range is 0.1 - 3 MPa. The high - temperature pressure curing process includes two processes. One is the curing cross - linking reaction of the structural resin, and the other is the high - temperature volatilization of the organic solvent NMP in the solid electrolyte solution. Therefore, the pressure needs to be applied by vacuum pumping or using a mold with vent holes.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) In the invention, the structural resin and the solid electrolyte are mixed. Although the mechanical properties of the solid electrolyte are relatively weak, it can effectively transfer the load to the structural resin, and the structural resin plays a major bonding and supporting role, making the mechanical properties much higher than those of the mixture of the structural resin and the liquid electrolyte.

[0031] (2) By mixing ceramic electrolyte particles or inorganic lithium salts, on the one hand, the ionic conductivity of the solid electrolyte is improved, and on the other hand, as rigid particles, they can toughen and strengthen the structural resin and the solid electrolyte in - situ.

[0032] (3) In the present invention, lithium metal is deposited on the carbon fiber at the negative electrode, thereby reducing the negative electrode potential, increasing the working voltage of the structural battery, and increasing the energy density.

[0033] (4) The method adopted in the present invention enables the morphology of lithium metal to be controllable, attached to the surface of carbon fiber, with good conductivity, a larger contact area, and it will not affect the wettability of the structural electrolyte and the fiber, thus generating pore defects and affecting the mechanical properties of the structural battery.

[0034] (5) The all - solid - state carbon fiber integrated structure battery realized in the present invention can withstand temperatures from - 20 °C to 150 °C. The addition of a high - mechanical - property structural resin better resists dendrite growth and has no risk of leakage.

[0035] (6) The high-modulus, high-strength, low-impedance all-solid-state lithium metal-deposited carbon fiber integrated structure battery implemented by the present invention makes full use of the electrical and mechanical properties of all materials, realizes the integration of structure and energy storage, has a significant weight reduction effect, and uses a structural resin for integrated hole sealing, and the whole can be used in the air. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Other features, objects, and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0037] Figure 1 Schematic diagram of the structure of the high-modulus, high-strength, low-impedance all-solid-state lithium metal-deposited carbon fiber integrated structure battery of the present invention;

[0038] Figure 2 Schematic diagram of the structure of the structural electrolyte of the present invention;

[0039] Among them, 1 is the lithium metal layer, 2 is the silver-plated layer, 3 is the active material layer, 4 is the carbon fiber, 5 is the insulating fiber, 6 is the structural electrolyte, 21 is the polymer electrolyte, 22 is the structural resin, 23 is the ceramic electrolyte particle, and 24 is the inorganic lithium salt particle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0041] The internal structure of the structural battery of the present invention is as Figure 1 shown. This embodiment is for the preparation and testing of a high-modulus, high-strength, low-impedance all-solid-state lithium metal-deposited carbon fiber integrated structure battery. The structure includes: a negative carbon fiber reinforcement formed by sequentially coating a silver-plated layer 2 and depositing a lithium metal layer 1 on the surface of a carbon fiber 4, a positive carbon fiber reinforcement formed by coating an active material layer 3 on the surface of the carbon fiber 4, an insulating fiber 5, and a structural electrolyte 6. Among them, the negative carbon fiber reinforcement and the positive carbon fiber reinforcement are arranged on both sides of the insulating fiber 5, and then the whole is placed in the structural electrolyte 6. The composition of the structural electrolyte is as Figure 2 shown, including a polymer electrolyte 21 dissolved with LiTFSI, a structural resin 22, ceramic electrolyte particles 23, and inorganic lithium salt particles 24.

[0042] The stacking order during the preparation of the structural battery is the negative carbon fiber reinforcement, the insulating fiber 5, and the positive carbon fiber reinforcement; the structural electrolyte 6 as the matrix is obtained by uniformly mixing an NMP solution dissolving LiTFSI and the polymer electrolyte 21, the structural resin liquid 22, and a resin curing agent containing ceramic electrolyte particles 23 and inorganic lithium salt particles 24, and then curing under heating and pressure.

[0043] The preparation method of the structural battery of the present invention includes the following steps:

[0044] Step S1: Use the silver mirror reaction to deposit a silver layer on the desized carbon fiber as the positive electrode, assemble it with a separator, a lithium metal negative electrode, and an electrolyte into a half-cell, perform constant current charge and discharge cycling, and after cycling several times, take out the silver-plated 2 carbon fiber 4 deposited with lithium metal 1 in an anhydrous and oxygen-free environment as the negative carbon fiber of the subsequent structural battery.

[0045] Step S2: Mix conductive carbon black particles (Super P): polyvinylidene fluoride (PVDF): active material in a certain mass ratio, dissolve them in N-methylpyrrolidone (NMP), and stir to form a positive electrode paste.

[0046] Step S3: Coat the positive electrode paste described in Step S2 on the desized carbon fiber, dry it at high temperature under vacuum to dry the NMP, and obtain the positive carbon fiber 4 coated with the active material 3.

[0047] Step S4: Lay stainless steel foils, the silver-plated 2 negative carbon fiber 4 deposited with lithium metal 1, insulating glass fibers 5, the positive carbon fiber 4 coated with the active material 3, and stainless steel foils in sequence on a concave die mold.

[0048] Step S5: In an anhydrous and oxygen-free environment, dissolve lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) in an NMP solution in a certain proportion and stir evenly to obtain a solution dissolving LiTFSI and the polymer electrolyte 21.

[0049] Step S6: In an anhydrous and oxygen-free environment, ultrasonically disperse the ceramic electrolyte particles 23 and the inorganic lithium salt particles 24 in a resin curing agent in a certain proportion, and uniformly mix the solution dissolving LiTFSI and the polymer electrolyte 21 described in Step S5 with the structural resin liquid 22 and the resin curing agent containing the ceramic electrolyte particles 23 and the inorganic lithium salt particles 24.

[0050] Step S7: In an anhydrous and oxygen-free environment, pour the structural electrolyte 6 described in Step S6 into the preform as a whole in Step S4 and cure it by heating at high temperature. After curing, use the structural resin 22 again to seal the holes.

[0051] Step S8: Conduct mechanical and electrical performance test verification to complete the performance experimental verification.

[0052] Example 1

[0053] This example provides a high modulus, high strength, low impedance all-solid-state lithium metal deposited carbon fiber integrated structure battery. The specific preparation steps are as follows:

[0054] T1. The T700 carbon fiber unidirectional tape after desizing by calcination at 400 °C for 1.5 h in air is used to obtain desized carbon fibers.

[0055] T2. The desized T700 carbon fiber unidirectional tape is immersed in 100 ml of a SnCl2 solution with a concentration of 15 g / L for 15 minutes for sensitization. A small amount of 2.5 g of glucose is added to 100 ml of concentrated sulfuric acid and heated to dissolve. Then, 100 ml of a 1% silver ammonia solution and 100 ml of a KOH solution with a concentration of 10 g / L are added. The T700 carbon fiber unidirectional tape is immersed therein at 30 °C and taken out after one minute. The carbon fiber is soaked in deionized water for 24 h to remove the residual solution.

[0056] T3. The silver-plated carbon fiber prepared in T2 is used as the positive electrode, and is assembled with a separator, a lithium metal negative electrode, and a LiPF6 electrolyte into a half-cell. Constant current charge and discharge cycling is carried out at 0.1 mA. After 100 cycles, in an anhydrous and oxygen-free environment, the silver-plated negative electrode T700 carbon fiber reinforcement deposited with lithium metal is taken out.

[0057] T4. Conductive carbon black particles (Super P): polyvinylidene fluoride (PVDF): LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811) are mixed in a mass ratio of 1:1:8, and dissolved in N-methylpyrrolidone (NMP) at a mass-to-volume ratio of 0.2 g / ml, and stirred to form a positive electrode paste.

[0058] T5. The positive electrode paste described in T4 is coated on the desized T700 carbon fiber unidirectional tape and dried at a high temperature (120 °C) under vacuum to dry the NMP, and a positive electrode T700 carbon fiber reinforcement containing NCM811 active material is obtained.

[0059] T6. Stainless steel foil, negative electrode T700 carbon fiber reinforcement, insulating glass fiber reinforcement, positive electrode T700 carbon fiber reinforcement, and stainless steel foil are sequentially laid on a concave die mold.

[0060] T7. Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) are dissolved in an NMP solution in a mass ratio of 2:3 in an anhydrous and oxygen-free environment, and stirred evenly to obtain a polymer electrolyte solution dissolved with LiTFSI and PVDF-HFP.

[0061] T8. Under an anhydrous and anaerobic environment, ultrasonic disperse LLZTO particles and LiF particles in MTM57 medium-temperature curing epoxy resin curing agent. Uniformly mix the LiTFSI and PVDF-HFP polymer electrolyte solution described in step T7 with the MTM57 medium-temperature curing epoxy resin liquid and the MTM57 resin curing agent containing LLZTO particles and LiF particles. The mass ratio of MTM57 medium-temperature curing epoxy resin: MTM57 medium-temperature curing epoxy resin curing agent: LiTFSI and PVDF-HFP described in step T7: LLZTO particles: LiF particles is 5:5:10:2:2;

[0062] T9. Under an anhydrous and anaerobic environment, pour the structural electrolyte described in T8 into the whole preform described in T6, and heat and cure it at 130 °C for 3 h under vacuum pressure. After curing, seal the holes with MTM57 epoxy resin again;

[0063] T10. Conduct mechanical and electrical performance test verification to complete the performance experimental verification.

[0064] The obtained structural battery has a tensile modulus of 51.6 GPa, a tensile strength of 466.3 MPa, a flexural modulus of 43.8 GPa, a flexural strength of 300.2 MPa, an energy density of 121.7 Wh / kg, an impedance of 385 Ω, and simultaneously has high mechanical and electrical properties.

[0065] Example 2

[0066] The preparation method of the structural battery provided in this example is basically the same as that in Example 1, except that: ceramic electrolyte particles and inorganic lithium salt particles are not added to the resin curing agent in step T8.

[0067] The obtained structural battery has a tensile modulus of 52.3 GPa, a tensile strength of 481.1 MPa, a flexural modulus of 39.2 GPa, a flexural strength of 279.2 MPa, an energy density of 105.2 Wh / kg, an impedance of 437 Ω, and simultaneously has high mechanical and electrical properties.

[0068] Comparative Example 1

[0069] The specific preparation steps of the structural battery provided in this comparative example are as follows:

[0070] T1. Mix carbon black conductive particles (Super P): polyvinylidene fluoride (PVDF): LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811) in a mass ratio of 1:1:8, dissolve it in N-methylpyrrolidone (NMP), and stir for 20 h to form a positive electrode paste;

[0071] T2. The T700 carbon fiber unidirectional tape after desizing by calcination at 400 °C for 1.5 h in air is taken to obtain the negative carbon fiber. A part of the negative carbon fiber is coated with the positive electrode paste described in T1 and dried at 120 °C under vacuum for 12 h to dry NMP, obtaining the positive carbon fiber coated with the energy storage material;

[0072] T3. On the concave die mold, a 10-μm-thick stainless steel foil is sequentially laid as the positive electrode current collector, a positive carbon fiber unidirectional tape in T2 as the positive electrode, a 0.1-mm-thick plain weave glass fiber, and another carbon fiber unidirectional tape in T2 as the negative electrode, and then the stainless steel foil is laid again as the negative electrode current collector;

[0073] T4. In the glove box, under an argon atmosphere, the E-51 room temperature curing epoxy resin and the LiPF6 ionic electrolyte are mixed in equal mass, poured into the preform stacked in T3, sealed and evacuated, and cured at 40 °C. After curing, the E-51 room temperature curing epoxy resin is used again for hole sealing;

[0074] T5. The electrical properties and mechanical properties of the structural battery obtained in T4 are tested to complete the performance verification.

[0075] The obtained structural battery has a tensile modulus of 24.5 GPa, a tensile strength of 260.8 MPa, a flexural modulus of 16.1 GPa, a flexural strength of 235.2 MPa, an energy density of 107.7 Wh / kg, and an impedance of 523 Ω, and its performance is poorer than that of Example 1.

[0076] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0077] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined arbitrarily.

Claims

1. A high-modulus, high-strength, low-impedance all-solid-state lithium metal-deposited carbon fiber structure battery, characterized in that It includes a positive carbon fiber reinforcement containing an active material, an insulating fiber, and a negative carbon fiber reinforcement. The negative carbon fiber reinforcement and the positive carbon fiber reinforcement are arranged on both sides of the insulating fiber, and the three are wrapped as a whole in a structural electrolyte; The structural electrolyte includes a polymer electrolyte in which LiTFSI is dissolved, a structural resin, ceramic electrolyte particles, and inorganic lithium salt particles; The negative carbon fiber reinforcement is formed by sequentially coating a silver plating layer and depositing a lithium metal layer on the surface of the carbon fiber, The positive carbon fiber reinforcement containing an active material is formed by coating an active material layer on the surface of the carbon fiber.

2. A preparation method of a high modulus, high strength, low impedance all-solid-state lithium metal deposited carbon fiber structure battery as described in claim 1, characterized in that, It includes the following steps: Step S1: Deposit a lithium metal layer on the surface of the carbon fiber to obtain the negative carbon fiber reinforcement of the structural battery; Step S2: Mix a conductive agent, a binder, and an active material, dissolve them in N-methylpyrrolidone, and stir to form a positive electrode paste; Step S3: Uniformly coat the positive electrode paste obtained in Step S2 on the carbon fiber, and dry it at a high temperature under vacuum to dry the N-methylpyrrolidone, and obtain the positive carbon fiber reinforcement containing an active material; Step S4: Lay a positive current collector, a positive carbon fiber reinforcement containing an active material, an insulating fiber, a negative carbon fiber reinforcement, and a negative current collector in sequence on a concave die mold to obtain a preform; Step S5: Under an anhydrous and anaerobic environment, dissolve lithium bis(trifluoromethanesulfonyl)imide and poly(vinylidene fluoride-hexafluoropropylene) in an N-methylpyrrolidone solution, and stir evenly to obtain a polymer electrolyte solution; Step S6: Under an anhydrous and anaerobic environment, uniformly mix the polymer electrolyte solution obtained in Step S5 with a structural resin and a resin curing agent to obtain a structural electrolyte; Step S7: Under an anhydrous and anaerobic environment, pour the structural electrolyte obtained in Step S6 into the preform obtained in Step S4 as a whole and heat it at a high temperature for curing. After curing, seal the holes with the structural resin again to obtain the structural battery.

3. The preparation method according to claim 2, characterized in that, In Step S1, the deposition of the lithium metal layer is specifically: plating a silver layer on the carbon fiber, serving as the positive electrode, assembling it with a separator, a lithium metal negative electrode, and an electrolyte into a half-cell, performing a constant current charge-discharge cycle. After several cycles, under an anhydrous and anaerobic environment, take out the carbon fiber deposited with the lithium metal layer.

4. The preparation method according to claim 3, wherein The silver plating is carried out by silver mirror reaction plating, specifically: dipping the desized carbon fiber unidirectional tape into a SnCl2 solution; adding a small amount of glucose to concentrated sulfuric acid and heating to dissolve it, then adding a silver ammonia solution and a KOH solution, and then dipping the carbon fiber unidirectional tape into it. After taking it out, rinse the carbon fiber with deionized water to remove the residual solution to obtain it.

5. The preparation method according to claim 2, wherein In Step S2, the active material includes one or more of ternary lithium metal oxides, lithium iron phosphate, lithium manganate, and lithium cobaltate.

6. The preparation method according to claim 2, wherein In Step S2, the mass ratio of the conductive agent, the binder, and the active material is 1:1:7 - 1:2:

8.

7. The preparation method according to claim 2, characterized in that, In Step S5, the mass ratio of lithium bis(trifluoromethanesulfonyl)imide and poly(vinylidene fluoride-hexafluoropropylene) is 1.5 - 2.5:

3.

8. The preparation method according to claim 2, characterized in that, In step S6, the resin curing agent further includes ceramic electrolyte particles and inorganic lithium salt particles; the ceramic electrolyte particles include Li 6.4 La3Zr 1.4 Ta 0.6 O 12 、Li 6.3 La3Zr 1.65 W 0.35 O 12 、Li7La3Zr2O 12 、Li 6.75 La3Zr 1.75 Nb 0.25 O 12 or more of them; the inorganic lithium salt particles are LiF.

9. The preparation method according to claim 2, characterized in that, In Step S6, the structural resin material is one of epoxy resins, bismaleimide resins, and polyimide resins for liquid molding; the resin curing agent includes one of acid anhydrides and amines.

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