A vibration-resistant maintenance-free lithium ion capacitor and a method for manufacturing the same

Abstract

The application relates to the technical field of lithium ion capacitors, and particularly discloses a vibration-resistant maintenance-free lithium ion capacitor and a preparation method thereof. The application takes titanium niobate@carbon particles as main raw materials, coats negative electrode slurry on a KH-550 modified etched copper foil after preparation, and forms a negative electrode sheet; takes nitrogen-doped mesoporous carbon microspheres as main raw materials, coats positive electrode slurry on a KH-560 modified etched aluminum foil after preparation, and forms a positive electrode sheet; and a polymer semi-solid electrolyte film is synthesized at the same time, and the lithium ion capacitor is assembled after stacking. The lithium ion capacitor has the advantages of low internal resistance, high power density, good vibration resistance, reliable capacitor device structure, stable electrical performance, and is particularly suitable for high-power energy storage and pulse discharge scenes in a harsh working environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium ion capacitors, in particular to a vibration-resistant and maintenance-free lithium ion capacitor and a preparation method thereof. BACKGROUND

[0002] With the improvement of people's awareness of environmental protection and sustainable utilization of resources, renewable clean energy such as light energy and wind energy gradually replaces fossil energy as the mainstream. However, the energy density of wind energy and solar energy is low, the supply continuity is poor, and the distribution is random, which needs to be converted into electrical energy and stored in an energy storage system to ensure continuous and stable energy supply. Therefore, the conversion and storage of such renewable energy is also the direction of industry development. Common energy storage elements include lithium ion batteries and supercapacitors.

[0003] As a new type of energy storage element combining the advantages of lithium ion batteries and supercapacitors, lithium ion capacitors (LIC) integrate high-capacity battery-type electrodes and high-rate capacitor-type electrodes into the same device, combining the faradic energy storage mechanism of lithium ion batteries and the non-faradic energy storage mechanism of supercapacitors, so as to have both high energy density of lithium ion batteries and high power density of supercapacitors, becoming an ideal power source for smart devices, automobiles, rail transportation, aerospace and other cutting-edge fields.

[0004] However, the existing lithium ion capacitors have the following technical problems in practical application: first, the structure has poor vibration resistance, and internal material delamination, solder drop or electrical performance attenuation easily occur under high-frequency vibration or impact environment, which is difficult to meet the requirements of high reliability of automobiles, rail transportation and industrial equipment; second, the internal resistance is high, which limits the power density and affects the rapid charging and discharging performance; third, some products need regular maintenance or replacement of electrolyte, which increases the operation and maintenance cost and system complexity. In view of the above problems, the present application provides a lithium ion capacitor with vibration resistance, low internal resistance, high power density and maintenance-free characteristics and a preparation method thereof, so as to improve the structural reliability, electrical performance stability and service life of the device, and is particularly suitable for high-power energy storage and pulse discharge scenarios in harsh working environments. SUMMARY

[0005] The present application aims to provide a vibration-resistant and maintenance-free lithium ion capacitor and a preparation method thereof, to solve the problems of poor structural stability, short service life, high internal resistance, insufficient power performance and the need for regular maintenance of the existing lithium ion capacitors in a vibrating environment, to realize long-term reliable operation under high-vibration and high-impact working conditions, to significantly reduce the internal resistance of the device, to improve the power density, and to have good air tightness and electrochemical stability, to achieve the purpose of maintenance-free operation, and to be particularly suitable for high-reliability application scenarios such as new energy vehicles, rail transportation, power systems and industrial equipment.

[0006] To solve the above technical problems, the present application provides the following technical solutions:

[0007] A vibration-resistant maintenance-free lithium ion capacitor, comprising a shell and a lead-out column located at the top of the outer side of the shell; the lead-out column comprises one negative lead-out column and three positive lead-out columns; the inner cavity of the shell is provided with a negative electrode sheet, a semi-solid electrolyte film and a positive electrode sheet;

[0008] The negative lead-out column is located at the central position of the top and is welded to the negative electrode sheet in the shell;

[0009] The positive lead-out columns are symmetrically distributed in an equilateral triangle around the negative lead-out column and are welded to the positive electrode sheet in the shell.

[0010] Further, the negative lead-out column is connected to the negative electrode tab or negative current collector by welding; the three positive lead-out columns are respectively connected to the positive electrode tab or positive current collector by welding.

[0011] Further, the lead-out column material is a high-conductivity metal material; the high-conductivity metal material is one of nickel-plated copper, aluminum and aluminum alloy.

[0012] Further, an insulating sealing structure is provided between the shell and the lead-out column to ensure the air tightness and electrical isolation performance; the insulating sealing structure is an epoxy resin insulating sealing layer.

[0013] Further, the included angle between the three positive lead-out columns is 120°, forming a symmetric triangular structure, which helps to improve the overall mechanical stability and vibration resistance of the lithium ion capacitor.

[0014] Further, the positive lead-out columns form a multi-point current output path, effectively reducing the equivalent series resistance (ESR) and improving the large current discharge capacity and thermal distribution uniformity of the lithium ion capacitor.

[0015] Further, the capacitor is convenient for modular assembly and can be connected to the busbar or conductive row by screwing, welding or plugging, and is suitable for high power density or high reliability occasions.

[0016] A preparation method of a vibration-resistant maintenance-free lithium ion capacitor, specifically comprising:

[0017] Step 1: titanium niobate@carbon particles and carbon nanotubes are used as raw materials to synthesize titanium niobate coating slurry, which is coated on a silane coupling agent KH-5 KH-550 modified etched copper foil to form a negative electrode sheet;

[0018] Step 2: nitrogen-doped mesoporous carbon microspheres and carbon nanotubes are used as raw materials to synthesize mesoporous carbon microsphere slurry, which is coated on a silane coupling agent KH-5 KH-560 modified etched aluminum foil to form a positive electrode sheet;

[0019] Step 3: preparing a semi-solid electrolyte film with PEO-b-PPO copolymer and lithium bis(trifluoromethanesulfonyl)imide as raw materials;

[0020] Step 4: after stacking the negative electrode sheet, the semi-solid electrolyte film and the positive electrode sheet in sequence, hot-pressing and compounding, then putting into a nickel-plated steel shell, injecting epoxy resin to form an epoxy resin insulation sealing layer, welding the positive electrode lead column and the negative electrode lead column and edge sealing, obtaining a vibration-resistant maintenance-free lithium ion capacitor.

[0021] As a limitation of the present application, the preparation method of the negative electrode sheet is:

[0022] Titanium oxysulfate and niobium pentachloride are added to deionized water, stirred for 20-30 min until completely dissolved, then glucose is added, mixed uniformly, the pH is adjusted to 2.5-3.5, and hydrothermal reaction is carried out at 180-200℃ for 20-24h. After the reaction is completed, cooling, filtering, washing the filtrate with deionized water, drying at 70-80℃, then transferring to a heating furnace, calcining at 800-820℃ under argon protection with a temperature rising rate of 5-10℃ / min for 3-4h, and naturally cooling after calcination to obtain titanium titanate@carbon particles;

[0023] Titanium titanate@carbon particles and carbon nanotubes are put into a ball mill and ball-mixed at 1500-2000rpm for 30-40min. After mixing, they are added to a carboxymethyl cellulose solution, stirred uniformly, then butadiene styrene rubber emulsion is added dropwise, and ultrasonic dispersion is carried out for 30-40min to obtain titanium titanate coating slurry. The titanium titanate coating slurry is coated on a silane coupling agent KH-550 modified etched copper foil by a coating machine to form a 150-170μm thick wet film. After coating, drying is carried out at 70-80℃ for 2-3h, vacuum drying is carried out at 110-120℃ for 2-3h, and after drying, rolling is carried out at a rolling pressure of 8-10MPa and a compaction density of 1.8-2.0g / cm 3 After rolling, the negative electrode sheet is immersed in a lithium nitride ethanol solution for 5-10min, taken out after impregnation, and reacted at 60-70℃ for 1.5-2h. After the reaction is completed, vacuum drying and solidification are carried out at 70-80℃ to obtain the negative electrode sheet.

[0024] Titanium oxysulfate and niobium pentachloride are condensed into titanium titanate during the hydrothermal reaction process, and at the same time, glucose is carbonized to form a carbon coating layer. The carbon coating layer can provide high lithium ion intercalation capacity, relieve the volume change during charging and discharging, inhibit electrode pulverization, and improve the conductivity of the electrode sheet.

[0025] Titanium niobate carbon particles in the slurry as the main active material, through the lithium ion insertion / deintercalation energy storage, carbon nanotubes through physical lapping form three-dimensional conductive network structure, accelerate electron transmission, enhance the conductivity of the electrode piece at the same time form anti-crack skeleton, improve the peeling strength of the coating and the vibration resistance of the electrode piece, butyl rubber emulsion as a flexible adhesive filled into the rigid conductive network structure, improve the flexibility of the coating, absorb the micro stress generated by the volume change in the charging and discharging process, reduce the peeling of the coating, improve the vibration resistance of the electrode piece; after rolling, immerse in lithium nitride ethanol solution for prelithiation, form a stable interface layer at the same time supplement the first irreversible capacity loss, improve the electrical performance of the capacitor.

[0026] As a limitation of the application, the mass ratio of titanium oxysulfate, niobium pentachloride and glucose is (16-20):(52-55):(15-25); the mass ratio of titanium niobate carbon particles, carbon nanotubes and butyl rubber emulsion in the titanium niobate coating slurry is (75-85):(7-10):(5-7); the carboxymethyl cellulose solution contains 2-4wt% carboxymethyl cellulose; the lithium nitride ethanol solution contains 5-7wt% lithium nitride.

[0027] As a limitation of the application, the preparation method of the positive electrode piece is:

[0028] Add resorcinol and formaldehyde aqueous solution to the mixture of ethanol and deionized water, stir at 40-45℃ for 0.5-1h to fully dissolve, then add F127 block copolymer and melamine, heat under water bath at 60-65℃ for 20-24h, after the reaction is completed, filter, wash the filtrate with ethanol and deionized water, dry at 70-80℃, then transfer to a heating furnace, heat to 350-400℃ at 5-10℃ / min under argon protection, continue to heat to 750-800℃ for 3-4h, after heating is completed, naturally cool down, get nitrogen-doped mesoporous carbon microspheres;

[0029] Put the nitrogen-doped mesoporous carbon microspheres and carbon nanotubes into a ball mill, ball mill mix at 300-500rpm for 20-30min, add PTFE emulsion and isopropanol, stir uniformly, then ultrasonic dispersion for 30-40min, get mesoporous carbon microsphere slurry, use coating machine to coat the mesoporous carbon microsphere slurry on the silane coupling agent KH-560 modified etched aluminum foil, form a 180-200μm thick wet film, after coating is completed, dry at 70-80℃ for 2-3h, heat to 110-120℃ for vacuum drying for 2-3h, after drying is completed, roll, the roll pressure is 8-10MPa, the compaction density is 1.8-2.0g / cm 3 , after rolling is completed, immerse in PTFE dispersion liquid for 5-10min, after immersion is completed, take out, vacuum dry at 150-160℃ for 30-60min to solidify, get the positive electrode piece.

[0030] Resorcinol and formaldehyde are condensed under alkaline conditions (provided by melamine hydrolysis) to form three-dimensional cross-linked phenolic resin microspheres, and the F127 block copolymer acts as a catalyst and a soft template to guide the formation of an ordered mesoporous structure while catalyzing the condensation, and at high temperatures, the melamine in the phenolic resin decomposes to form active nitrogen, and at the same time, the phenolic resin itself carbonizes to form nitrogen-doped mesoporous carbon microspheres.

[0031] The nitrogen-doped mesoporous carbon microspheres in the slurry serve as the main active substance, and the nitrogen atoms embedded in the surface carbon lattice provide lone pair electrons and surface carbon-nitrogen bonds (-C=N) to reduce the charge transfer impedance, and the mesoporous structure is conducive to ion transmission, thereby improving the conductivity of the electrode plate, and the spherical structure disperses the vibration stress through point contact, the carbon skeleton structure improves the strength, and the pores absorb mechanical energy, thereby improving the mechanical properties and vibration resistance of the electrode plate, and the carbon nanotubes in the slurry form a three-dimensional conductive network structure while forming a π-π conjugation with the functional groups of the nitrogen-doped carbon, thereby reducing the interface impedance and improving the conductivity and mechanical properties of the coating, and the PTFE emulsion acts as a binder to reduce the contact angle of the coating and improve the electrolyte permeability, and in addition, the PTFE emulsion is fibrous when solidified, thereby absorbing the charge and discharge stress and anchoring the active substance.

[0032] As a limitation of the present application, the mass ratio of the resorcinol, the F127 block copolymer and the melamine is (10-20):(5-10):(3-5); the formaldehyde aqueous solution contains 35-37wt% formaldehyde, and the volume ratio of the formaldehyde aqueous solution, ethanol and deionized water is (15-25):(100-120):(100-120); in the mesoporous carbon microsphere slurry, the PTFE emulsion contains 60-65wt% PTFE, and the mass ratio of the nitrogen-doped mesoporous carbon microspheres, carbon nanotubes, PTFE emulsion and isopropyl alcohol is (85-95):(5-10):(10-20):(430-450); and in the PFTE dispersion, the concentration of PFTE is 0.1-0.2mol / L.

[0033] As a limitation of the present application, the preparation method of the semi-solid electrolyte membrane is as follows:

[0034] Mesoporous silica and aminopropyltriethoxysilane are sequentially added to 100-120mL of toluene, stirred uniformly, and then refluxed at 80-90℃ for 5-6h, after the reaction is completed, centrifuged, washed with ethanol, and dried at 70-80℃ for 2.5-3h to obtain aminated mesoporous silica, which is added to 50-70mL of hexanol, stirred uniformly, and then polyethylene glycol methacrylate and benzophenone are sequentially added, ultrasonically dispersed for 20-30min, deoxygenated by nitrogen bubbling, and irradiated with 365nm ultraviolet light for 30-40min, after the reaction is completed, centrifuged, washed with methanol, and vacuum dried at 50-60℃ for 3-4h to obtain PEGMA grafted mesoporous silica.

[0035] The PEO-b-PPO copolymer, lithium bis-trifluoromethanesulfonimide and PEGMA grafted mesoporous silica are added into acetonitrile, and after stirring at 40-50 DEG C until fully dissolved, the PEGMA grafted mesoporous silica and benzophenone are added, and after ultrasonic dispersion for 0.8-1 h, the semi-solid electrolyte film with a thickness of 100-120 microns is obtained by coating on a glass plate and curing under 365 nm ultraviolet light for 10-15 min.

[0036] The PEGMA is grafted on the surface of mesoporous silica, and the long chain of PEGMA can not only reduce the interface impedance, improve the compatibility with PEO electrolyte, buffer vibration stress and improve the vibration resistance of the coating, but also coordinate lithium ions through the ether oxygen bond (-CH2OCH2-) in the structure, thereby improving the ionic conductivity.

[0037] The ether oxygen bond (-CH2OCH2-) in the PEO chain segment of the PEO-b-PPO copolymer in the electrolyte film coordinates lithium ions to form an ion conduction channel, the flexible chain structure absorbs vibration energy, the PPO chain segment reduces the crystallinity of PEO to improve the mobility of the PEO chain segment, thereby improving the conductivity and vibration resistance of the film, the lithium bis-trifluoromethanesulfonimide serves as a lithium ion source to stably provide lithium ions, the PEGMA flexible chain of the PEGMA grafted mesoporous silica buffers stress, and the mechanical properties and vibration resistance of the film are enhanced together with the rigid mesoporous silica structure, and meanwhile, the mesoporous structure can also adsorb electrolyte molecules to relieve concentration polarization.

[0038] As a limitation of the application, the mass ratio of the mesoporous silica and aminopropyl triethoxysilane is (5-7):(2-3), the mass ratio of the aminated mesoporous silica and polyethylene glycol methacrylate is (5-7):(10-20), and the mass ratio of the PEO-b-PPO copolymer, lithium bis-trifluoromethanesulfonimide and PEGMA grafted mesoporous silica is (70-80):(22-26):(8-10).

[0039] As a limitation of the application, when the silane coupling agent KH-550 is used to modify the etched copper foil, the mass ratio of the silane coupling agent KH-550, ethanol and deionized water is 1:(90-95):(5-10), and when the silane coupling agent KH-560 is used to modify the etched copper foil, the mass ratio of the silane coupling agent KH-560, isopropyl alcohol and deionized water is (1-3):(90-95):(3-7).

[0040] Compared with the prior art, the application has the following beneficial effects:

[0041] The application adopts titanium niobate carbon particles as the main active material of the negative electrode slurry, the titanium niobate stores energy through lithium ion insertion / extraction, the carbon layer on the surface provides mechanical properties and vibration resistance, and can also relieve the volume change in the charging and discharging process and inhibit electrode pulverization, thereby improving the conductive performance of the electrode sheet, after the slurry is prepared and coated on the etched copper foil modified by silane coupling agent KH-550, the capacitor negative electrode sheet prepared has good mechanical properties, vibration resistance and conductive performance, and the slurry has good combination with the copper foil and is not easy to separate and fail.

[0042] The application adopts nitrogen-doped mesoporous carbon microspheres as the main active material of the positive electrode slurry, nitrogen atoms embedded in the surface carbon lattice provide lone pair electrons and surface carbon-nitrogen bonds (-C=N) to reduce charge transfer impedance, and the mesoporous structure is beneficial to ion transmission, so that the conductive performance of the electrode sheet is excellent, after the slurry is prepared and coated on the etched aluminum foil modified by silane coupling agent KH-560, the capacitor positive electrode sheet prepared has good conductive performance and vibration resistance.

[0043] The lithium ion capacitor formed by combining the above-mentioned negative electrode sheet, positive electrode sheet and self-made semi-solid electrolyte film has the advantages of low internal resistance, high power density and good vibration resistance, the capacitor device structure is reliable, the electrical performance is stable, and it is particularly suitable for high-power energy storage and pulse discharge scenes in harsh working environments. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the application will be described below in a clear and complete manner. Obviously, the described embodiments are only some of the embodiments of the application, rather than all the embodiments. The terms used in the embodiments are used for describing specific specific embodiments, rather than limiting the protection scope of the application. The amount used in the embodiments is a laboratory small test, which can be scaled up proportionally. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0045] Etched copper foil (thickness: 15 μm, roughness: 1.5 μm), etched aluminum foil (thickness: 20 μm, roughness: 0.5 μm), carbon nanotube (length: 1-5 μm, diameter: 30±10 nm), butyl rubber emulsion (solid content: 40-50 wt%), F127 block copolymer (molecular weight: 12600 g / mol), PTFE emulsion (particle size: 0.1-0.5 μm, solid content: 60 wt%), PEO-b-PPO copolymer (molecular weight: 600000 g / mol, block mass ratio: PEO:PPO=70:30), mesoporous silica (particle size: 20 nm, specific surface area: 300 m 2Nickel-plated steel shell (thickness: 0.5 mm, thickness of nickel-plated layer: 10 μm).

[0046] The preparation method of the etched copper foil modified by the silane coupling agent KH-550 is as follows:

[0047] 1 g of the silane coupling agent KH-550 is added to a mixture of 95 g of ethanol and 5 g of deionized water, and after being stirred uniformly, the pH is adjusted to 5 to obtain a KH-550 ethanol solution. The etched copper foil is immersed in the KH-550 ethanol solution at 60°C for 10 min, taken out after the immersion is completed, and cured at 120°C for 1 h to obtain the etched copper foil modified by the silane coupling agent KH-550.

[0048] The preparation method of the etched aluminum foil modified by the silane coupling agent KH-560 is as follows:

[0049] 2 g of the silane coupling agent KH-560 is added to a mixture of 95 g of isopropyl alcohol and 3 g of deionized water, and after being stirred uniformly, the pH is adjusted to 8 to obtain a KH-560 isopropyl alcohol solution. The etched copper foil is immersed in the KH-560 isopropyl alcohol solution at 50°C for 30 min, taken out after the immersion is completed, and cured at 150°C for 1 h to obtain the etched aluminum foil modified by the silane coupling agent KH-560.

[0050] The preparation method of the mesoporous silica grafted with PEGMA is as follows:

[0051] 5 g of mesoporous silica and 2 g of aminopropyl triethoxysilane are sequentially added to 100 mL of toluene, stirred uniformly, and then refluxed at 80°C for 6 h. After the reaction is completed, centrifugation is performed, washing is performed with ethanol, and drying is performed at 70°C for 3 h to obtain aminated mesoporous silica. 5 g of the aminated mesoporous silica is added to 50 mL of hexanol, and after being stirred uniformly, 10 g of polyethylene glycol methacrylate and 0.1 g of benzophenone are sequentially added. After ultrasonic dispersion for 30 min, oxygen is removed by nitrogen bubbling, and 365 nm ultraviolet light is irradiated for 30 min. After the reaction is completed, centrifugation is performed, washing is performed with methanol, and vacuum drying is performed at 50°C for 3 h to obtain the mesoporous silica grafted with PEGMA.

[0052] Embodiment 1: A preparation method of a vibration-resistant maintenance-free lithium ion capacitor, specifically as follows:

[0053] Step 1: 16 g of titanyl sulfate and 52 g of niobium pentachloride are added to 200 mL of deionized water, stirred for 30 min until completely dissolved, 15 g of glucose is added, mixed uniformly, the pH is adjusted to 3, and hydrothermal reaction is performed at 200°C for 24 h. After the reaction is completed, cooling is performed, filtration is performed, the filtrate is washed with deionized water, drying is performed at 70°C, and then the product is transferred to a heating furnace. Under the protection of argon, the temperature is increased to 800°C at a rate of 5°C / min, and calcination is performed for 4 h. After the calcination is completed, natural cooling is performed to obtain titania@carbon particles.

[0054] Step 2: 75 g titanium niobate@carbon particles, 7 g carbon nanotubes were put into a ball mill and mixed at 2000 rpm for 30 min. After mixing, 5 g of butadiene-styrene rubber emulsion was added and uniformly stirred. After ultrasonic dispersion for 30 min, titanium niobate coating slurry was obtained. The titanium niobate coating slurry was coated on the etched copper foil modified by silane coupling agent KH-550 using a coating machine. The wet film thickness was 150 μm. After coating, drying was performed at 80 °C for 2 h, and then vacuum drying was performed at 120 °C for 2 h. After drying, rolling was performed at a pressure of 10 MPa, and the compacted density was 1.8 g / cm 3 After rolling, the sample was immersed in 5 wt% lithium nitride ethanol solution for 10 min. After immersion, the sample was taken out and reacted at 60 °C for 2 h. After reaction, vacuum drying and solidification were performed at 80 °C to obtain a negative electrode sheet.

[0055] Step 3: 10 g of resorcinol, 15 mL of 37 wt% formaldehyde aqueous solution were added to a mixture of 100 mL of ethanol and 100 mL of deionized water. After stirring at 40 °C for 1 h to fully dissolve, 5 g of F127 block copolymer and 3 g of melamine were added. Reaction was performed at 60 °C water bath for 24 h. After reaction, filtration was performed. The filtrate was washed with ethanol and deionized water. After drying at 70 °C, the sample was transferred to a heating furnace. Under argon protection, the sample was heated to 350 °C at a rate of 5 °C / min for 2 h, and then heated to 800 °C for 3 h. After heating, the sample was naturally cooled to obtain nitrogen-doped mesoporous carbon microspheres.

[0056] Step 4: 85 g of nitrogen-doped mesoporous carbon microspheres and 5 g of carbon nanotubes were put into a ball mill and mixed at 300 rpm for 30 min. 10 g of 60 wt% PTFE emulsion and 450 g of isopropyl alcohol were added. After stirring, ultrasonic dispersion was performed for 30 min to obtain mesoporous carbon microsphere slurry. The mesoporous carbon microsphere slurry was coated on the etched aluminum foil modified by silane coupling agent KH-560 using a coating machine. The wet film thickness was 180 μm. After coating, drying was performed at 80 °C for 2 h, and then vacuum drying was performed at 120 °C for 2 h. After drying, rolling was performed at a pressure of 10 MPa, and the compacted density was 1.8 g / cm 3 After rolling, the sample was immersed in 0.1 mol PTFE dispersion liquid for 5 min. After immersion, the sample was taken out and vacuum dried at 150 °C for 30 min to solidify and obtain a positive electrode sheet.

[0057] Step 5: 70 g of PEO-b-PPO copolymer and 22 g of lithium bis-trifluoromethanesulfonimide were added to 200 mL of acetonitrile. After stirring at 40 °C until fully dissolved, 8 g of PEGMA grafted mesoporous silica and 0.1 g of benzophenone were added. After ultrasonic dispersion at 500 W for 1 h, the sample was coated on a glass plate and cured under 365 nm ultraviolet light for 10 min to obtain a semi-solid electrolyte film with a thickness of 100 μm.

[0058] Step 6: After the negative electrode sheet, the semi-solid electrolyte film, and the positive electrode sheet are sequentially stacked, heat pressing is performed at 80℃ and 0.5MPa for 10min, then the product is loaded into a nickel-plated steel shell, injected with epoxy resin, and welded with positive and negative lead posts and edges, thereby obtaining a vibration-resistant maintenance-free lithium ion capacitor.

[0059] Embodiment 2: A method for preparing a vibration-resistant maintenance-free lithium ion capacitor, specifically comprising:

[0060] Step 1: 18g titanium oxysulfate and 54g niobium pentachloride are added to 200mL deionized water, stirred for 30min until completely dissolved, then 20g glucose is added, mixed uniformly, the pH is adjusted to 3, and hydrothermal reaction is performed at 200℃ for 24h. After the reaction is completed, the product is cooled, filtered, and the filtrate is washed with deionized water. After drying at 70℃, the product is transferred to a heating furnace, heated to 800℃ at a rate of 5℃ / min under argon protection, and calcined for 4h. After calcination is completed, the product is naturally cooled to obtain titanium titanoniobate@carbon particles;

[0061] Step 2: 80g titanium titanoniobate@carbon particles and 9g carbon nanotubes are placed in a ball mill and ball-mixed at 2000rpm for 30min. After mixing, the product is added to 250mL 2wt% carboxymethyl cellulose solution, stirred uniformly, and then 6g butadiene-styrene rubber emulsion is added dropwise. After ultrasonic dispersion for 30min, a titanium titanoniobate coating slurry is obtained. The titanium titanoniobate coating slurry is coated on a silane coupling agent KH-550 modified etched copper foil using a coating machine, and the wet film thickness is 160μm. After coating is completed, the product is dried at 80℃ for 2h and then vacuum dried at 120℃ for 2h. After drying is completed, the product is rolled at a pressure of 10MPa, and the compaction density is 1.8g / cm3. After rolling is completed, the product is immersed in 5wt% lithium nitride ethanol solution for 10min, taken out after immersion is completed, and reacted at 60℃ for 2h. After reaction is completed, the product is vacuum dried and solidified at 80℃ to obtain a negative electrode sheet.

[0062] Step 3: 15g resorcinol and 15mL 37wt% formaldehyde aqueous solution are added to a mixture of 100mL ethanol and 100mL deionized water. After being completely dissolved by stirring at 40℃ for 1h, 7g F127 block copolymer and 4g melamine are added. After reaction is completed under heating at 60℃ for 24h, the product is filtered and washed with ethanol and deionized water. After drying at 70℃, the product is transferred to a heating furnace, heated to 350℃ at a rate of 5℃ / min under argon protection, and heated for 2h. The temperature is then increased to 800℃ and heated for 3h. After heating is completed, the product is naturally cooled to obtain nitrogen-doped mesoporous carbon microspheres.

[0063] Step 4: 90 g nitrogen-doped mesoporous carbon microspheres and 7 g carbon nanotubes were put into a ball mill for 300 rpm ball milling mixing for 30 min, 15 g of 60 wt% PTFE emulsion and 440 g of isopropyl alcohol were added, and after stirring uniformly, ultrasonic dispersion was performed for 30 min to obtain a mesoporous carbon microsphere slurry. The mesoporous carbon microsphere slurry was coated on a silane coupling agent KH-560 modified etched aluminum foil by a coating machine, the wet film thickness was 190 μm, after coating, drying was performed at 80℃ for 2 h, and then vacuum drying was performed at 120℃ for 2 h. After drying, rolling was performed, the rolling pressure was 10 MPa, and the compaction density was 1.8 g / cm 3 After rolling, the positive electrode sheet was obtained by immersing in 0.1 mol PTFE dispersion liquid for 5 min, and then taking out, vacuum drying at 150℃ for 30 min for solidification.

[0064] Step 5: 75 g of PEO-b-PPO copolymer, 24 g of lithium bis-trifluoromethanesulfonimide, and 0.1 g of benzophenone were added to 200 mL of acetonitrile, and after stirring at 40℃ until completely dissolved, 9 g of PEGMA grafted mesoporous silica was added. After ultrasonic dispersion at 500 W for 1 h, coating was performed on a glass plate, and 365 nm ultraviolet light was cured for 10 min to obtain a semi-solid electrolyte film with a thickness of 110 μm.

[0065] Step 6: The negative electrode sheet, semi-solid electrolyte film, and positive electrode sheet were sequentially stacked, and then hot-pressed at 80℃ and 0.5 MPa for 10 min. Subsequently, the product was loaded into a nickel-plated steel shell, epoxy resin was injected, the positive electrode lead column and the negative electrode lead column were welded, and the edges were sealed to obtain a vibration-resistant maintenance-free lithium ion capacitor.

[0066] Example 3: A preparation method of a vibration-resistant maintenance-free lithium ion capacitor, specifically:

[0067] Step 1: 20 g of titanyl sulfate and 55 g of niobium pentachloride were added to 200 mL of deionized water, stirred for 30 min until completely dissolved, then 25 g of glucose was added, mixed uniformly, the pH was adjusted to 3, and hydrothermal reaction was performed at 200℃ for 24 h. After reaction, cooling, filtration, and washing of the filtrate with deionized water, drying at 70℃, the product was transferred to a heating furnace and calcined at 800℃ for 4 h under argon protection with a temperature increase rate of 5℃ / min. After calcination, natural cooling was performed to obtain titanium titanate@carbon particles.

[0068] Step 2: 85 g of titanium niobate@carbon particles and 10 g of carbon nanotubes were put into a ball mill and mixed at 2000 rpm for 30 min. After mixing, 20 g of 60 wt% PTFE emulsion and 430 g of isopropyl alcohol were added and stirred uniformly. After ultrasonic dispersion for 30 min, a mesoporous carbon microsphere slurry was obtained. The mesoporous carbon microsphere slurry was coated on a silane coupling agent KH-560 modified etched aluminum foil using a coating machine, with a wet film thickness of 200 μm. After coating, drying was performed at 80°C for 2 h, and then vacuum drying was performed at 120°C for 2 h. After drying, rolling was performed at a rolling pressure of 10 MPa, and the compacted density was 1.8 g / cm

[0069] Step 3: 20 g of resorcinol, 15 mL of 37 wt% formaldehyde aqueous solution were added to a mixture of 100 mL of ethanol and 100 mL of deionized water. After stirring at 40°C for 1 h to fully dissolve, 10 g of F127 block copolymer and 5 g of melamine were added. Reaction was performed at 60°C water bath for 24 h. After reaction, filtration was performed, and the filtrate was washed with ethanol and deionized water. After drying at 70°C, it was transferred to a heating furnace. Under argon protection, it was heated to 350°C at a rate of 5°C / min for 2 h, and then heated to 800°C for 3 h. After heating, it was naturally cooled to obtain nitrogen-doped mesoporous carbon microspheres.

[0070] Step 4: 95 g of nitrogen-doped mesoporous carbon microspheres and 10 g of carbon nanotubes were put into a ball mill and mixed at 300 rpm for 30 min. 20 g of 60 wt% PTFE emulsion and 430 g of isopropyl alcohol were added and stirred uniformly. After ultrasonic dispersion for 30 min, a mesoporous carbon microsphere slurry was obtained. The mesoporous carbon microsphere slurry was coated on a silane coupling agent KH-560 modified etched aluminum foil using a coating machine, with a wet film thickness of 200 μm. After coating, drying was performed at 80°C for 2 h, and then vacuum drying was performed at 120°C for 2 h. After drying, rolling was performed at a rolling pressure of 10 MPa, and the compacted density was 1.8 g / cm 3 , after rolling, it was immersed in a 0.1 mol PTFE dispersion liquid for 5 min. After immersion, it was taken out and vacuum dried at 150°C for 30 min to obtain a positive electrode sheet.

[0071] Step 5: 80 g of PEO-b-PPO copolymer and 26 g of lithium bis-trifluoromethanesulfonimide were added to 200 mL of acetonitrile. After stirring at 40°C until fully dissolved, 10 g of PEGMA grafted mesoporous silica and 0.1 g of benzophenone were added. After ultrasonic dispersion at 500 W for 1 h, it was coated on a glass plate and cured under 365 nm ultraviolet light for 10 min to obtain a semi-solid electrolyte film with a thickness of 120 μm.

[0072] Step 6: After the negative electrode sheet, semi-solid electrolyte film, and positive electrode sheet are stacked in sequence, hot-pressing is performed at 80°C and 0.5 MPa for 10 min, and then the product is loaded into a nickel-plated steel shell, injected with epoxy resin, welded with a positive electrode lead column and a negative electrode lead column, and sealed, to obtain a vibration-resistant maintenance-free lithium ion capacitor.

[0073] Based on Example 1, the following comparative experiments are performed, specifically Comparative Example 1, Comparative Example 2, and Comparative Example 3, as described below.

[0074] Comparative Example 1: This comparative example relates to a method for preparing a corrosion-resistant stainless steel positive electrode current collector, which differs from Example 1 in that titanium niobate-carbon particles are not added to the slurry, specifically as follows:

[0075] Step 1: 7 g of carbon nanotubes are added to a 250 mL 2 wt% carboxymethyl cellulose solution, and after stirring to uniformity, 5 g of butadiene-styrene rubber emulsion is added dropwise and ultrasonically dispersed for 30 min to obtain a negative electrode coating slurry. The negative electrode coating slurry is coated on a silane coupling agent KH-550 modified etched copper foil using a coating machine, with a wet film thickness of 150 μm. After coating, drying is performed at 80°C for 2 h, and then vacuum drying is performed at 120°C for 2 h. After drying, rolling is performed at a rolling pressure of 10 MPa, with a compacted density of 1.8 g / cm3. After rolling, immersion is performed in a 5 wt% lithium nitride ethanol solution for 10 min. After immersion, the product is removed and reacted at 60°C for 2 h. After reaction, vacuum drying and solidification are performed at 80°C to obtain a negative electrode sheet.

[0076] Step 2: 10 g of resorcinol and 15 mL of a 37 wt% formaldehyde aqueous solution are added to a mixture of 100 mL of ethanol and 100 mL of deionized water. After stirring at 40°C for 1 h to fully dissolve, 5 g of F127 block copolymer and 3 g of melamine are added. Reaction is performed at 60°C in a water bath for 24 h. After reaction, filtration is performed, and the filtrate is washed with ethanol and deionized water. After drying at 70°C, the product is transferred to a heating furnace and heated to 350°C at a rate of 5°C / min under argon protection for 2 h. The temperature is then increased to 800°C and held for 3 h. After heating, the product is naturally cooled to obtain nitrogen-doped mesoporous carbon microspheres.

[0077] Step 3: 85 g of nitrogen-doped mesoporous carbon microspheres and 5 g of carbon nanotubes are placed in a ball mill and mixed at 300 rpm for 30 min. 10 g of a 60 wt% PTFE emulsion and 450 g of isopropyl alcohol are added, and after stirring to uniformity, ultrasonic dispersion is performed for 30 min to obtain a mesoporous carbon microsphere slurry. The mesoporous carbon microsphere slurry is coated on a silane coupling agent KH-560 modified etched aluminum foil using a coating machine, with a wet film thickness of 180 μm. After coating, drying is performed at 80°C for 2 h, and then vacuum drying is performed at 120°C for 2 h. After drying, rolling is performed at a rolling pressure of 10 MPa, with a compacted density of 1.8 g / cm3. 3, after rolling, immerse in 0.1 mol PTFE dispersion solution for 5 min, take out after impregnation, vacuum drying at 150 ℃ for 30 min to solidify, to obtain the positive electrode sheet;

[0078] Step 4: 70 g of PEO-b-PPO copolymer, 22 g of lithium bis-trifluoromethanesulfonimide was added to 200 mL of acetonitrile, stirred at 40 ℃ until completely dissolved, then 8 g of PEGMA grafted mesoporous silica and 0.1 g of benzophenone were added, ultrasonic dispersion for 1 h, then coated on a glass plate, 365 nm ultraviolet light curing for 10 min, then taken out, to obtain a semi-solid electrolyte film with a thickness of 100 μm;

[0079] Step 5: The negative electrode sheet, semi-solid electrolyte film, and positive electrode sheet were stacked in order, and then hot-pressed at 80 ℃ and 0.5 MPa for 10 min, then put into a nickel-plated steel shell, injected with epoxy resin, welded the positive electrode lead column and the negative electrode lead column, and sealed the edge to obtain a vibration-resistant maintenance-free lithium ion capacitor.

[0080] Comparative Example 2: This comparative example relates to a preparation method of a corrosion-resistant stainless steel positive current collector, which is different from Example 1 in that no nitrogen-doped mesoporous carbon microspheres are added to the slurry, specifically:

[0081] Step 1: 16 g of titanyl sulfate and 52 g of niobium pentachloride were added to 200 mL of deionized water, stirred for 30 min until completely dissolved, then 15 g of glucose was added and mixed evenly, the pH was adjusted to 3, and hydrothermal reaction was carried out at 200 ℃ for 24 h. After the reaction was completed, it was cooled, filtered, and the filtrate was washed with deionized water. After drying at 70 ℃, it was transferred to a heating furnace and calcined at 800 ℃ under argon protection at a rate of 5 ℃ / min for 4 h. After calcination, it was naturally cooled to obtain titanium titanate@carbon particles;

[0082] Step 2: 75 g of titanium titanate@carbon particles and 7 g of carbon nanotubes were placed in a ball mill and mixed at 2000 rpm for 30 min. After mixing, they were added to 250 mL of a 2 wt% carboxymethyl cellulose solution, stirred evenly, and then 5 g of butadiene-styrene rubber emulsion was added and ultrasonic dispersed for 30 min to obtain a titanium titanate coating slurry. The titanium titanate coating slurry was coated on a silane coupling agent KH-550 modified etched copper foil using a coating machine, with a wet film thickness of 150 μm. After coating, it was dried at 80 ℃ for 2 h and then vacuum dried at 120 ℃ for 2 h. After drying, it was rolled at a pressure of 10 MPa, with a compaction density of 1.8 g / cm3. After rolling, it was immersed in a 5 wt% lithium nitride ethanol solution for 10 min, taken out after impregnation, reacted at 60 ℃ for 2 h, and then vacuum dried and solidified at 80 ℃ to obtain a negative electrode sheet;

[0083] Step 3: 5 g of carbon nanotubes and 10 g of 60 wt% PTFE emulsion were added to 450 g of isopropyl alcohol, and after stirring uniformly, ultrasonic dispersion was performed for 30 min to obtain a PTFE slurry. The PTFE slurry was coated on a silane coupling agent KH-560 modified etched aluminum foil by a coating machine, the wet film thickness was 180 μm, and after coating was completed, drying was performed at 80°C for 2 h, and then vacuum drying was performed at 120°C for 2 h. After drying was completed, rolling was performed at a rolling pressure of 10 MPa, and the compacted density was 1.8 g / cm3. After rolling was completed, immersion was performed in 0.1 mol of a PTFE dispersion liquid for 5 min, and after immersion was completed, the product was taken out, vacuum drying was performed at 150°C for 30 min to solidify, and a positive electrode sheet was obtained;

[0084] Step 4: 70 g of a PEO-b-PPO copolymer, 22 g of lithium bis-trifluoromethanesulfonimide, and 200 mL of acetonitrile were stirred at 40°C until completely dissolved, 8 g of PEGMA grafted mesoporous silica and 0.1 g of benzophenone were added, ultrasonic dispersion was performed at 500 W for 1 h, and then coating was performed on a glass plate. UV light curing was performed at 365 nm for 10 min, and a semi-solid electrolyte film was obtained, with a thickness of 100 μm;

[0085] Step 5: The negative electrode sheet, the semi-solid electrolyte film, and the positive electrode sheet were sequentially stacked, and then hot pressing was performed at 80°C and 0.5 MPa for 10 min. Subsequently, the product was loaded into a nickel-plated steel shell, epoxy resin was injected, the positive electrode lead column and the negative electrode lead column were welded, and the edges were sealed to obtain a vibration-resistant maintenance-free lithium ion capacitor.

[0086] Comparative Example 3: This comparative example relates to a preparation method of a corrosion-resistant stainless steel positive electrode current collector, which is different from Example 1 in that a lithium bis-trifluoromethanesulfonimide electrolyte is directly injected into the capacitor, and the specific process is as follows:

[0087] Step 1: 16 g of titanyl sulfate and 52 g of niobium pentachloride were added to 200 mL of deionized water, stirred for 30 min until completely dissolved, 15 g of glucose was added, mixed uniformly, the pH was adjusted to 3, and hydrothermal reaction was performed at 200°C for 24 h. After the reaction was completed, cooling was performed, and the filtrate was washed with deionized water. After drying at 70°C, the product was transferred to a heating furnace, and calcination was performed at 800°C at a heating rate of 5°C / min under argon protection for 4 h. After calcination was completed, natural cooling was performed to obtain titanium titanate@carbon particles;

[0088] Step 2: 75 g of titanium niobate@carbon particles and 7 g of carbon nanotubes were put into a ball mill and mixed at 2000 rpm for 30 min. After mixing, they were added to 250 mL of a 2 wt% carboxymethyl cellulose solution. After stirring uniformly, 5 g of butadiene-styrene rubber emulsion was added and ultrasonically dispersed for 30 min. Titanium niobate coating slurry was obtained. The titanium niobate coating slurry was coated on a silane coupling agent KH-550 modified etched copper foil using a coating machine. The wet film thickness was 150 μm. After coating, it was dried at 80℃ for 2 h, and then vacuum dried at 120℃ for 2 h. After drying, it was rolled with a rolling pressure of 10 MPa and a compaction density of 1.8 g / cm3. After rolling, it was immersed in a 5 wt% lithium nitride ethanol solution for 10 min. After immersion, it was taken out and reacted at 60℃ for 2 h. After reaction, it was vacuum dried and solidified at 80℃ to obtain a negative electrode sheet.

[0089] Step 3: 10 g of resorcinol and 15 mL of 37 wt% formaldehyde aqueous solution were added to a mixture of 100 mL of ethanol and 100 mL of deionized water. After stirring at 40℃ for 1 h to fully dissolve, 5 g of F127 block copolymer and 3 g of melamine were added. The reaction was carried out at 60℃ water bath heating for 24 h. After reaction, filtration was performed. The filtrate was washed with ethanol and deionized water. After drying at 70℃, it was transferred to a heating furnace and heated to 350℃ at 5℃ / min under argon protection for 2 h. The temperature was further increased to 800℃ and heated for 3 h. After heating, it was naturally cooled to obtain nitrogen-doped mesoporous carbon microspheres.

[0090] Step 4: 85 g of nitrogen-doped mesoporous carbon microspheres and 5 g of carbon nanotubes were put into a ball mill and mixed at 300 rpm for 30 min. 10 g of 60 wt% PTFE emulsion and 450 g of isopropyl alcohol were added. After stirring uniformly, ultrasonic dispersion was performed for 30 min to obtain mesoporous carbon microsphere slurry. The mesoporous carbon microsphere slurry was coated on a silane coupling agent KH-560 modified etched aluminum foil using a coating machine. The wet film thickness was 180 μm. After coating, it was dried at 80℃ for 2 h, and then vacuum dried at 120℃ for 2 h. After drying, it was rolled with a rolling pressure of 10 MPa and a compaction density of 1.8 g / cm 3 After rolling, it was immersed in a 0.1 mol PTFE dispersion liquid for 5 min. After immersion, it was taken out and vacuum dried at 150℃ for 30 min to solidify and obtain a positive electrode sheet.

[0091] Step 5: The negative electrode sheet and the positive electrode sheet were sequentially stacked. Then, 12 wt% bis-trifluoromethanesulfonylimide lithium acetonitrile solution was vacuum injected. After heat sealing at 80℃ using an aluminum plastic film, it was put into a nickel-plated steel shell. Epoxy resin was injected. The positive electrode lead and the negative electrode lead were welded and the edges were sealed to obtain a vibration-resistant maintenance-free lithium ion capacitor.

[0092] Detection experiment:

[0093] Capacitor internal resistance test: test the method of internal resistance measurement in section 6.4.1.4 of "Super Capacitor Part 1: General" (GB / T 34870.1-2017), charge the lithium ion capacitor to the rated voltage Ur with a constant current I in a 25℃ environment, record the charging time t0, and then stabilize for 30 minutes, then discharge to the minimum working voltage Umin with a constant current I, record the voltage U1 at t0+30ms, repeat the measurement three times, and calculate the internal resistance of the lithium ion capacitor.

[0094] Capacitor power density test: test the method of maximum mass power density measurement in section 6.4.1.5 of "Super Capacitor Part 1: General" (GB / T 34870.1-2017) based on the internal resistance of the lithium ion capacitor obtained in the above test, measure the mass of the lithium ion capacitor monomer, and calculate the power density of the lithium ion capacitor.

[0095] Capacitor vibration resistance test: test the vibration test in section 7.4 of "Fixed Capacitor for Electronic Equipment Part 1: General Specification". First, charge the lithium ion capacitor to the rated voltage Ur with a constant current I using a direct current power supply, and then discharge to the minimum working voltage Umin with a constant current I, record the time t1 required for the capacitor voltage to drop from 90% of the rated voltage to the minimum working voltage Umin, repeat the measurement three times, calculate the capacitance of the capacitor, then fix the capacitor on the vibration table, connect the electrical performance detector, start the vibration table, and vibrate at a sine frequency of 10-500Hz with an acceleration of 20G. Test in x / y / z axis directions, each direction for 2h, after testing in three directions, remove the capacitor, test the capacitance and internal resistance of the capacitor after vibration according to the above capacitance test method and internal resistance test method, and record the capacitance change rate and internal resistance change rate of the lithium ion capacitor after vibration.

[0096]

[0097] Conclusion: From the test data, it can be seen that compared with the comparative example, the lithium ion capacitor prepared by the method of the embodiment has lower internal resistance and higher power density, and after the vibration test, the capacitance change rate and internal resistance change rate are lower than those of the comparative example. The vibration-resistant maintenance-free lithium ion capacitor provided by the application has low internal resistance, high power density, and good vibration resistance, reliable device structure, stable electrical performance, and is especially suitable for high-power energy storage and pulse discharge scenes in harsh working environments.

[0098] It will be apparent to those skilled in the art that the application is not limited to the details of the above-exemplified embodiments and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. The embodiments should therefore be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

1. A method of making a vibration resistant, maintenance free lithium ion capacitor, characterized by: Specifically, Step 1: titanium niobate@carbon particles and carbon nanotubes are used as raw materials to synthesize titanium niobate coating slurry, which is coated on a silane coupling agent KH-550 modified etched copper foil to form a negative electrode sheet; Step 2: nitrogen-doped mesoporous carbon microspheres and carbon nanotubes are used as raw materials to synthesize mesoporous carbon microsphere slurry, which is coated on a silane coupling agent KH-560 modified etched aluminum foil to form a positive electrode sheet; Step 3: PEO-b-PPO copolymer and lithium bis-trifluoromethanesulfonimide are used as raw materials to prepare a semi-solid electrolyte membrane; Step 4: the negative electrode sheet, semi-solid electrolyte membrane and positive electrode sheet are sequentially stacked, then hot-pressed and combined, then placed in a nickel-plated steel shell, epoxy resin is injected to form an epoxy resin insulation sealing layer, the positive electrode lead column and the negative electrode lead column are welded and the edges are sealed to obtain a vibration-resistant maintenance-free lithium ion capacitor; The negative electrode lead column is located at the central position of the top of the shell and is welded to the negative electrode sheet in the shell; The positive electrode lead column is three, symmetrically distributed in an equilateral triangle around the negative electrode lead column and welded to the positive electrode sheet in the shell; The preparation method of the semi-solid electrolyte membrane is as follows: Mesoporous silica and aminopropyl triethoxysilane are sequentially added to 100-120 mL of toluene, stirred uniformly, and then refluxed at 80-90°C for 5-6 hours. After the reaction is completed, centrifugation is performed, ethanol is used for washing, and drying is performed at 70-80°C for 2.5-3 hours to obtain aminated mesoporous silica. The aminated mesoporous silica is added to 50-70 mL of hexanol, stirred uniformly, and then polyethylene glycol methacrylate and benzophenone are added. After ultrasonic dispersion for 20-30 minutes, oxygen is removed by nitrogen bubbling, and 365nm ultraviolet light is irradiated for 30-40 minutes. After the reaction is completed, centrifugation is performed, methanol is used for washing, and vacuum drying is performed at 50-60°C for 3-4 hours to obtain PEGMA grafted mesoporous silica; PEO-b-PPO copolymer and lithium bis-trifluoromethanesulfonimide are added to acetonitrile, stirred at 40-50°C until fully dissolved, then PEGMA grafted mesoporous silica and benzophenone are added, ultrasonic dispersion is performed for 0.8-1 hour, then coated on a glass plate, 365nm ultraviolet light is cured for 10-15 minutes, and then removed to obtain a 100-120μm thick semi-solid electrolyte membrane; The mass ratio of mesoporous silica to aminopropyl triethoxysilane is (5-7):(2-3); the mass ratio of aminated mesoporous silica to polyethylene glycol methacrylate is (5-7):(10-20); and the mass ratio of PEO-b-PPO copolymer, lithium bis-trifluoromethanesulfonimide and PEGMA grafted mesoporous silica is (70-80):(22-26):(8-10).

2. The method for preparing a vibration-resistant, maintenance-free lithium-ion capacitor according to claim 1, characterized in that: The material of the lead column is a high-conductivity metal material, and the high-conductivity metal material is one of aluminum, aluminum alloy and nickel-plated copper.

3. The method of claim 1, wherein the method further comprises: The preparation method of the negative electrode sheet is as follows: ​ Titanium oxysulfate, niobium pentachloride were added into deionized water, stirred for 20-30 min until completely dissolved, then glucose was added, mixed uniformly, pH was adjusted to 2.5-3.5, hydrothermal reaction was carried out at 180-200℃ for 20-24 h, after reaction was completed, cooling, filtration, the filtrate was washed with deionized water, dried at 70-80℃, then transferred to a heating furnace, calcined at 800-820℃ under argon protection with a heating rate of 5-10℃ / min for 3-4 h, after calcination was completed, natural cooling, titanium niobate@carbon particles were obtained; Titanium niobate@carbon particles, carbon nanotubes are put into a ball mill and mixed at 1500-2000 rpm for 30-40 min. After mixing, they are added to a carboxymethyl cellulose solution, stirred uniformly, and then dropwise added with a styrene-butadiene rubber emulsion. After ultrasonic dispersion for 30-40 min, titanium niobate coating slurry is obtained. The titanium niobate coating slurry is coated on a silane coupling agent KH-550 modified etched copper foil by a coating machine to form a 150-170 μm thick wet film. After coating, drying is performed at 70-80 °C for 2-3 h, vacuum drying is performed at 110-120 °C for 2-3 h, and after drying, rolling is performed at a pressure of 8-10 MPa to a compaction density of 1.8-2.0 g / cm 3 After rolling, immersion in a lithium nitride ethanol solution is performed for 5-10 min, after which the product is taken out, reacted at 60-70 °C for 1.5-2 h, and after reaction, vacuum drying and solidification are performed at 70-80 °C to obtain a negative electrode sheet.

4. The method of claim 3, wherein the method further comprises: The mass ratio of titanium oxysulfate, niobium pentachloride and glucose was (16-20):(52-55):(15-25); the mass ratio of titanium niobate@carbon particles, carbon nanotubes and butadiene styrene rubber emulsion in the titanium niobate coating slurry was (75-85):(7-10):(5-7); the carboxymethyl cellulose solution contained 2-4wt% carboxymethyl cellulose; the lithium nitride ethanol solution contained 5-7wt% lithium nitride. ​ 5. The method of claim 1, wherein the method further comprises: The preparation method of the positive electrode sheet was as follows: ​ Resorcinol, formaldehyde aqueous solution were added into a mixture of ethanol and deionized water, stirred at 40-45℃ for 0.5-1 h until completely dissolved, then F127 block copolymer, melamine were added, reacted at 60-65℃ under water bath heating for 20-24 h, after reaction was completed, filtration, the filtrate was washed with ethanol and deionized water, dried at 70-80℃, then transferred to a heating furnace, heated at 350-400℃ under argon protection with a heating rate of 5-10℃ / min for 1-2 h, continued to heat to 750-800℃ for 3-4 h, after heating was completed, natural cooling, nitrogen-doped mesoporous carbon microspheres were obtained; The nitrogen-doped mesoporous carbon microspheres and carbon nanotubes are put into a ball mill and mixed at 300-500 rpm for 20-30 min, PTFE emulsion and isopropyl alcohol are added, and after stirring uniformly, ultrasonic dispersion is performed for 30-40 min to obtain a mesoporous carbon microsphere slurry. The mesoporous carbon microsphere slurry is coated on a silane coupling agent KH-560 modified etched aluminum foil by a coating machine to form a wet film with a thickness of 180-200 μm. After coating is completed, drying is performed at 70-80 °C for 2-3 h, vacuum drying is performed at 110-120 °C for 2-3 h, and after drying is completed, rolling is performed at a pressure of 8-10 MPa, and the compacted density is 1.8-2.0 g / cm 3 After rolling is completed, immersion in a PTFE dispersion liquid is performed for 5-10 min, and after immersion is completed, the product is taken out, vacuum drying is performed at 150-160 °C for 30-60 min for solidification, and a positive electrode sheet is obtained. The nitrogen-doped mesoporous carbon microspheres and carbon nanotubes are put into a ball mill and mixed at 300-500 rpm for 20-30 min, PTFE emulsion and isopropyl alcohol are added, and after stirring uniformly, ultrasonic dispersion is performed for 30-40 min to obtain a mesoporous carbon microsphere slurry. The mesoporous carbon microsphere slurry is coated on a silane coupling agent KH-560 modified etched aluminum foil by a coating machine to form a wet film with a thickness of 180-200 μm. After coating is completed, drying is performed at 70-80 °C for 2-3 h, vacuum drying is performed at 110-120 °C for 2-3 h, and after drying is completed, rolling is performed at a pressure of 8-10 MPa, and the compacted density is 1.8-2.0 g / cm 3 After rolling is completed, immersion in a PTFE dispersion liquid is performed for 5-10 min, and after immersion is completed, the product is 6. The method of claim 5, wherein the vibration-resistant maintenance-free lithium-ion capacitor is prepared by the steps of: The mass ratio of resorcinol, F127 block copolymer and melamine was (10-20):(5-10):(3-5); the formaldehyde aqueous solution contained 35-37wt% formaldehyde, the volume ratio of formaldehyde aqueous solution, ethanol, deionized water was (15-25):(100-120):(100-120); in the mesoporous carbon microsphere slurry, the PTFE emulsion contained 60-65wt% PTFE, the mass ratio of nitrogen-doped mesoporous carbon microspheres, carbon nanotubes, PTFE emulsion and isopropanol was (85-95):(5-10):(10-20):(430-450); in the PFTE dispersion, the concentration of PFTE was 0.1-0.2mol / L. ​ 7. The method of claim 1, wherein the method further comprises: When the silane coupling agent KH-550 was used to modify the etched copper foil, the mass ratio of silane coupling agent KH-550, ethanol and deionized water was 1:(90-95):(5-10); when the silane coupling agent KH-560 was used to modify the etched aluminum foil, the mass ratio of silane coupling agent KH-560, isopropanol and deionized water was (1-3):(90-95):(3-7). ​

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