Stretchable fibrous supercapacitor based on coaxial structure

Abstract

The utility model discloses a stretchable fibrous super capacitor based on a coaxial structure. Comprising a porous fiber electrode, a gel electrolyte and a carbon fiber membrane, the gel electrolyte and the carbon fiber membrane sequentially wrap the electrode, the porous fiber electrode and the carbon fiber membrane are connected with an external circuit through wires and packaged through a stretchable thin film, the length of the porous fiber electrode is equal to the width of the carbon fiber membrane, and the porous fiber electrode has excellent stretchability. The reticular structure carbon fiber membrane has a good microstructure and mechanical properties, gel electrolyte is loaded on the surfaces of the porous fiber electrode and the carbon fiber membrane, and the porous fiber electrode coated with the gel electrolyte is coated with the carbon fiber membrane to prepare the fibrous supercapacitor with a coaxial structure. The fibrous supercapacitor shows high capacity and has high stability to tensile deformation.

Description

TECHNICAL FIELD

[0001] The utility model belongs to super capacitor technical field, concretely relates to the stretchable fiber-like super capacitor based on coaxial structure. BACKGROUND

[0002] With the continuous development of miniaturized electronic products and the popularity of connected devices, wearable electronic devices have changed from the concept depicted in science fiction novels to various mature consumer products. Considering the durability of wearable devices, high requirements are placed on their bending deformation and wear resistance, such as flexible sensors, wearable displays, and intelligent human-machine interfaces. However, traditional rigid structure power supply systems hinder the development of the flexibility, miniaturization, and integration of these devices. Stretchable fibers have better biocompatibility, stretchability, transparency, and wear resistance. In addition to the inherent wear resistance and flexibility, fiber-based super capacitors can also ensure better comfort when worn and better integration with clothing. The fiber-like super capacitor powers the wearable sensor, which can be used to monitor physiological signals, motion information, and environmental information in real time, serving intelligent medical care and personal health management.

[0003] The challenge currently faced by the fiber-like super capacitor is that its energy storage capacity is significantly lower than that of existing rigid traditional energy storage devices. According to the different assembly structures of the fiber-like super capacitor, it can be further divided into parallel structure, winding structure, and coaxial structure. Although the parallel and winding structures show superiority in terms of easy preparation operation and adjustable diameter size. However, the effective interface area between the two fiber electrodes and the mass load of active materials are relatively low, which affects the energy and power density of the device.

[0004] The coaxial structure not only provides a larger, tighter, and more effective interface area between the electrodes, which is conducive to a high mass load of active materials, but also has a more stable structure that can withstand repeated deformation. However, most current fiber-like super capacitors are still limited by poor dynamic electrochemical stability, i.e., there are problems of insufficient electrochemical performance of the super capacitor during stretching and poor stretching stability. Therefore, designing and developing a fiber-like super capacitor with high capacity and high stretching stability is of great significance and research value for the application and development of super capacitors in wearable electronic devices. SUMMARY

[0005] To solve the shortcomings and deficiencies of the prior art, the purpose of the utility model is to provide a stretchable fiber-like super capacitor based on a coaxial structure.

[0006] The utility model achieves the purpose by the following technical solutions:

[0007] A stretchable fiber-shaped supercapacitor based on coaxial structure, comprising a porous fiber electrode, a gel electrolyte layer and a carbon fiber membrane electrode;

[0008] The porous fiber electrode serves as the inner core of the capacitor, the gel electrolyte layer is wrapped on the outer side of the porous fiber electrode, and the carbon fiber membrane electrode is wrapped on the outer side of the gel electrolyte layer.

[0009] Preferably, the stretchable fiber-shaped supercapacitor based on coaxial structure further comprises a stretchable film, and the stretchable film is wrapped on the outer side of the carbon fiber membrane electrode. The stretchable film is mainly used for packaging.

[0010] Preferably, the stretchable fiber-shaped supercapacitor based on coaxial structure further comprises a wire, and the porous fiber electrode and the carbon fiber membrane electrode are respectively connected with an external circuit through the wire.

[0011] Preferably, the stretchable fiber-shaped supercapacitor based on coaxial structure is a columnar body.

[0012] Preferably, the diameter of the inner core of the porous fiber electrode is 300-1000 μm, and the pore size is 0.1-10 μm.

[0013] Preferably, the thickness of the gel electrolyte layer is 1-5 mm.

[0014] Preferably, the carbon fiber membrane electrode is in a net structure, and the thickness is 0.1-0.5 mm.

[0015] Preferably, the thickness of the stretchable film is 0.1-1 mm.

[0016] Preferably, the porous fiber electrode is prepared from an elastomeric polymer and a conductive filler, the elastomeric polymer is one of thermoplastic polyurethane, styrene-butadiene-styrene block copolymer and styrene-ethylene / butylene-styrene block copolymer, the conductive filler is at least one of nanotube, activated carbon, MXene and graphene, and the mass percentage of the conductive filler to the elastomeric polymer is 0.1%-10%.

[0017] Preferably, the gel electrolyte layer is obtained by mixing a polymer and an acid solution, the polymer is one of polyvinyl alcohol, polyacrylic acid, polyacrylamide and polymethyl methacrylate, and the mass fraction is 4%-10%, the acid solution is one of sulfuric acid solution and phosphoric acid solution, and the concentration is 0.1-0.5 mol / L.

[0018] Preferably, the porous fiber electrode and the carbon fiber membrane electrode are immersed in the gel electrolyte, and the gel electrolyte is ensured to completely penetrate into the electrodes and the fiber membrane.

[0019] Preferably, the stretchable film is one of polydimethylsiloxane, Ecoflex, styrene-ethylene / butylene-styrene block copolymer, and thermoplastic polyurethane.

[0020] Preferably, the length of the porous fiber electrode and the width of the carbon fiber film are equal.

[0021] Compared with the prior art, the coaxial structure fiber-like super capacitor has the following advantages and beneficial effects:

[0022] The coaxial structure fiber-like super capacitor prepared by the coaxial structure fiber-like super capacitor has the advantages of large area specific capacitance, short ion migration distance, low charge transfer resistance, high stability to tensile deformation, and wide application prospect in wearable biological monitoring and health management. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The structure schematic diagram of the coaxial structure fiber-like stretchable super capacitor prepared in the embodiment is shown, wherein 1 is a porous fiber electrode, 2 is a carbon fiber film electrode, 3 is a wire, 4 is a stretchable film, and 5 is a gel electrolyte layer.

[0024] Figure 2 The electron microscope picture of the porous fiber electrode in the embodiment is shown.

[0025] Figure 3 The electron microscope picture of the carbon fiber film in the embodiment is shown.

[0026] Figure 4 The charge-discharge curve of the porous fiber electrode in the embodiment under different current densities is shown.

[0027] Figure 5 The cyclic voltammetry curve of the fiber-like super capacitor prepared in the embodiment under different scanning speeds is shown.

[0028] Figure 6 The performance comparison chart of the coaxial structure fiber-like super capacitor before and after stretching in the embodiment is shown. DETAILED DESCRIPTION

[0029] The coaxial structure fiber-like super capacitor will be further described in detail below in combination with the embodiments and the drawings, but the implementation manner of the coaxial structure fiber-like super capacitor is not limited to this.

[0030] In the embodiment of the coaxial structure fiber-like super capacitor, no specific conditions are marked, and the conventional conditions or the conditions recommended by the manufacturer are used. The raw materials, reagents and the like used without marking the manufacturer are all conventional products that can be purchased on the market.

[0031] A stretchable fiber-like super capacitor based on a coaxial structure has the structure as shown in Figure 1As shown, it comprises a porous fiber electrode 1 as the inner core, a gel electrolyte layer 5, a carbon fiber membrane electrode 2, a wire 3 and a stretchable film 4.

[0032] The gel electrolyte layer 5 is coated on the outer side of the porous fiber electrode 1 as the inner core, the carbon fiber membrane electrode 2 is coated on the outer side of the gel electrolyte layer 5, the porous fiber electrode 1 and the carbon fiber membrane electrode 2 are respectively connected with the external circuit through the wire 3, that is, the positive and negative electrodes of the supercapacitor are connected with the outside world, and the stretchable film 4 is coated on the outer side of the carbon fiber membrane electrode 2 to realize the packaging of the capacitor.

[0033] The gel electrolyte fully infiltrates the porous fiber electrode 1 and the carbon fiber membrane electrode 2, and the length of the porous fiber electrode 1 is equal to the width of the carbon fiber membrane 2.

[0034] The diameter of the porous fiber electrode as the inner core is 330 μm, and the pore size is 3.4 μm.

[0035] The thickness of the gel electrolyte layer is 2 mm.

[0036] The carbon fiber membrane electrode is a net structure, and the thickness is 0.5 mm.

[0037] The thickness of the stretchable film is 0.1 mm.

[0038] As shown in the figure, Figure 2 The porous fiber electrode is prepared from thermoplastic polyurethane and conductive filler, the conductive filler is a mixed filler of carbon nanotubes and graphene, and the mass percentage of the conductive filler and the elastomer polymer is 0.5%.

[0039] Figure 3 The figure shows the electron microscope image of the carbon fiber membrane.

[0040] Figure 4 The figure shows the charge and discharge curves of the porous fiber electrode under different current densities, wherein the diameter of the porous fiber is 330 μm, and the pore size is 3.4 μm.

[0041] The gel electrolyte layer is an acidic electrolyte, which is obtained by mixing polyvinyl alcohol and phosphoric acid solution according to the mass ratio of 1:10, wherein the concentration of the phosphoric acid solution is 0.1 mol / L. The porous fiber electrode 1 and the carbon fiber membrane electrode 2 are fully infiltrated with the gel electrolyte to ensure that the electrolyte completely penetrates into the electrodes and the fiber membrane.

[0042] The stretchable film is a polydimethylsiloxane film.

[0043] Figure 5 , Figure 6The electrochemical performance of the supercapacitor in the original state and the electrochemical performance of the supercapacitor in the state of being stretched by 10% are compared.

[0044] The fiber-shaped supercapacitor described in the above embodiment not only has good stretchability, but also has the advantages of fast ion transmission channels and rich active sites, so that the fiber-shaped supercapacitor with the coaxial structure has excellent mechanical properties and outstanding electrochemical performance (high energy density, large specific capacitance, fast charging and discharging), and has wide application potential in the wearable field.

[0045] The above embodiment is a preferred embodiment of the present application, but the embodiments of the present application are not limited by the above embodiment, and any change, modification, substitution, combination, simplification made without departing from the spirit and principles of the present application should be an equivalent replacement mode, and all are included in the protection scope of the present application.

Claims

1. A stretchable fiber-shaped supercapacitor based on coaxial structure, characterized in that, The porous fiber electrode, the gel electrolyte layer and the carbon fiber membrane electrode are included. The porous fiber electrode is used as the inner core of the capacitor, the gel electrolyte layer is coated on the outer side of the porous fiber electrode, and the carbon fiber membrane electrode is coated on the outer side of the gel electrolyte layer. The carbon fiber membrane electrode is in a net structure.

2. The stretchable fiber supercapacitor based on coaxial structure according to claim 1, wherein, The porous fiber electrode and the carbon fiber membrane electrode are connected with an external circuit through wires.

3. The stretchable fiber-shaped ultracapacitor based on coaxial structure according to claim 1, wherein, A stretchable film is further included, and the stretchable film is coated on the outer side of the carbon fiber membrane electrode.

4. The stretchable fiber supercapacitor based on coaxial structure according to claim 1, wherein, The stretchable fiber-like super capacitor based on the coaxial structure is a columnar body.

5. The stretchable fiber supercapacitor based on coaxial structure according to claim 1, wherein, The length of the porous fiber electrode is equal to the width of the carbon fiber membrane.

6. The stretchable fiber supercapacitor based on coaxial structure according to claim 1, wherein, The diameter of the inner core of the porous fiber electrode is 300-1000 μm, and the pore size is 0.1-10 μm.

7. The stretchable fiber-shaped ultracapacitor based on coaxial structure according to claim 1, wherein, The thickness of the gel electrolyte layer is 1-5 mm.

8. The stretchable fiber-shaped ultracapacitor based on coaxial structure according to claim 1, wherein, The thickness of the carbon fiber membrane electrode is 0.1-0.5 mm.

9. The stretchable fiber-shaped ultracapacitor based on coaxial structure according to claim 3, wherein, The thickness of the stretchable film is 0.1-1 mm.

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