CN1529334A - Polyaniline/carbon nanotube hybrid supercapacitor - Google Patents

Abstract

A polyaniline/carbon nanotube hybrid supercapacitor relates to a structural design of a hybrid supercapacitor. The present invention uses conductive polyaniline and carbon nanotubes as active materials for the positive and negative electrodes of the supercapacitor respectively, and its structure is: positive electrode current collector/polyaniline electrode/electrolyte and diaphragm/carbon nanotube electrode/negative electrode current collector. Polyaniline/carbon nanotube hybrid supercapacitors can give full play to the potential of electrode materials, form coordination and complementarity, and make them have higher specific energy and specific power. Compared with carbon nanotube supercapacitors, the specific energy of polyaniline/carbon nanotube hybrid supercapacitors increased by 135%, and the average specific power increased by 7%; compared with polyaniline supercapacitors, polyaniline/carbon nanotube hybrid The specific energy of the type supercapacitor is increased by 30%, and the average specific power is increased by 100%.

Description

Polyaniline/carbon nanotube hybrid supercapacitor

technical field

The invention relates to an energy storage element, in particular to the structural design of a polyaniline/carbon nanotube hybrid supercapacitor.

Background technique

In the past two decades, with the rapid emergence and development of new technologies in the fields of information technology, electronic products, and vehicle energy, people have paid more attention to the research and development of novel supercapacitors. Supercapacitors, also known as electrochemical capacitors, are a new type of energy storage element between ordinary capacitors and secondary batteries. Compared with traditional batteries, supercapacitors have the advantages of high specific power, many charge-discharge cycles, and short charge-discharge time; compared with traditional electrolytic capacitors, they have the advantages of large specific capacity and high specific energy. Ultracapacitors have many potential applications. High-power ultracapacitors can be used as load balancing devices for electric vehicles, providing auxiliary power during the start, acceleration, and climbing stages of electric vehicles, and quickly storing large currents generated by generators during braking. . Using it to match the battery can make the battery in the best power supply state, thereby prolonging the service life of the battery, improving energy utilization efficiency, and reducing costs. Medium and low-power supercapacitors can also be used as auxiliary power supplies for welding machines, flashlights, notebook computers, and handheld electronic devices.

Conductive polyaniline electrode supercapacitors have the advantages of high specific energy, low cost, and different polymer structures can be selected through molecular design, and have attracted widespread attention. The conductive polyaniline electrode supercapacitor is a fast and reversible p-type doping or dedoping redox reaction in the electronically conductive polymer film on the electrode, so that the polyaniline electrode stores high-density charges and has a high Faraday standard. capacitance, thereby achieving high-density charge storage. But the main voltage range of polyaniline storage charge is below 1V, such as: "Symmetricredox supercapacitor with conducting polyaniline electrodes" published in "Journal of Power Sources" by Kwang Sun Ryu et al. (2002, volume 103, pages 305-309), It also shows that the main voltage range of polyaniline to store charge is below 1V, which limits the improvement of specific energy. Since the specific energy E=1/2 CV ² , if the operating voltage can be managed to increase, the specific energy of the supercapacitor can be greatly increased.

In November 1991, Iijima, an electron microscope expert from NEC, first discovered carbon nanotubes under a high-resolution transmission electron microscope (HRTEM), which aroused widespread concern. Carbon nanotubes are one-dimensional tubular carbon materials composed of graphite-like hexagonal grids. Micron, its lamellar spacing is 0.34nm, which is slightly larger than that of graphite (0.335nm). Carbon nanotubes have a huge specific surface area, good electrical conductivity and excellent chemical stability, so the use of carbon nanotubes in the preparation of electric double layer capacitors has become a research hotspot, but the specific capacity of carbon nanotube supercapacitors is low. For example, Zhang Jianyu, Zeng Xiaoshu, Cai Jiesong, etc. published "Electric Double Layer Capacitor Based on Carbon Nanotubes" (2002, Vol. As positive and negative electrode active materials, carbon nanotube-based electric double layer capacitors have been prepared; for example, "Preparation of Carbon Nanotube Solid Plates for Electric Double Layer Capacitors" published by Zhang Bin et al. in "Acta Electronics" (2000 , vol. 28, No. 8, pp. 13-15), using carbon nanotubes as positive and negative active materials, prepared an electric double layer capacitor based on carbon nanotubes, and its specific energy is low.

The materials of the positive and negative electrodes of the hybrid supercapacitor are different, and the mechanism of the two electrodes storing charge is different. For example, "Hybrid electrochemical capacitors based on polyaniline and activated carbon electrodes" (2002, volume 111, pages 185-190) published in "Journal of Power Sources" by Jong Hyeok Park et al. uses polyaniline as the positive electrode active material and activated carbon as the negative electrode Active material, 6mol/L KOH aqueous solution as electrolyte, Celgard3501 as diaphragm. However, the contact resistance between activated carbon particles is relatively large, especially when the activated carbon particles are small, the contact resistance between activated carbon particles will be very large, which makes the conductivity of activated carbon not as high as that of carbon nanotubes, which is not conducive to improving the specific power of supercapacitors. The electrochemical stability is not as good as carbon nanotubes, especially when a high operating voltage is applied, activated carbon is prone to side reactions and generates by-products such as carbon dioxide, which is very important for improving the operating voltage, specific energy and cycle stability of supercapacitors. unfavorable. The diameter of carbon nanotubes is nanoscale, which makes carbon nanotubes have a high specific surface area in a larger space, and the length of carbon nanotubes can reach microns or longer, with a large aspect ratio, which makes Carbon nanotubes have high electrical conductivity, which is conducive to improving the specific power of supercapacitors, and carbon nanotubes have a relatively stable structure. The electrochemical stability of carbon nanotubes is better than that of activated carbon. When a high operating voltage is applied , not prone to side reactions. These are beneficial for improving the specific energy and cycle stability of supercapacitors. But so far, there is no hybrid supercapacitor assembled with polyaniline as the positive electrode active material and carbon nanotubes as the negative electrode material.

Contents of the invention

The purpose of the present invention is to provide a polyaniline/carbon nanotube hybrid supercapacitor, which can give full play to the potential of the positive and negative electrode materials and form a coordinated and complementary effect, thereby further improving the specific energy and specific power of the supercapacitor. index.

The technical scheme of the present invention is as follows: a polyaniline/carbon nanotube hybrid supercapacitor, its structure contains positive electrode current collector, positive electrode, electrolyte and diaphragm, negative electrode and negative electrode current collector successively, it is characterized in that: the described The positive electrode is made of polyaniline or a composite material composed of polyaniline and carbon material, and the carbon material is one or more of carbon nanotubes, activated carbon, carbon fiber or acetylene black, wherein the mass percentage of carbon material is less than 30% %; The negative electrode is made of carbon nanotubes or a mixture of carbon nanotubes and activated carbon, carbon fiber or acetylene black, wherein the mass percentage of activated carbon, carbon fiber or acetylene black is less than 30%.

In order to meet people's different needs for supercapacitors under different conditions, so that the performance of supercapacitors has more excellent performance, the mass ratio range of positive electrode materials and negative electrode materials used in the present invention is 0.1 to 5, and the optimal mass ratio range is 0.2 to 2. .

The electrolyte in the present invention uses LiPF ₆ (lithium hexafluorophosphate), LiBF ₄ (lithium tetrafluoroborate), LiClO ₄ (lithium perchlorate), LiCF ₃ SO ₃ (lithium trifluorosulfonate), (C ₂ H ₅ ) ₄ NPF ₆ (tetraethylammonium hexafluorophosphate), (C ₂ H ₅ ) ₄ NBF ₄ (tetraethylammonium tetrafluoroborate), (C ₂ H ₅ ) ₄ NClO ₄ (tetraethylammonium perchlorate) , (C ₂ H ₅ ) ₄ NCF ₃ SO ₃ (tetraethylammonium trifluorosulfonate), (C ₄ H ₉ ) ₄ NPF ₆ (tetrabutylammonium hexafluorophosphate), (C ₄ H ₉ ) ₄ NBF ₄ (tetrabutylammonium tetrafluoroborate), (C ₄ H ₉ ) ₄ NClO ₄ (tetrabutylammonium perchlorate), (C ₄ H ₉ ) ₄ NCF ₃ SO ₃ (tetrabutylammonium trifluorosulfonate ) or their mixture as the electrolyte, using propylene carbonate, ethylene carbonate, butylene carbonate, acetonitrile or their mixture as the solvent.

Compared with the prior art, the present invention has the following advantages and outstanding effects: the present invention uses polyaniline or a composite material with polyaniline as the main component as the positive electrode active material of the supercapacitor, and carbon nanotubes or carbon nanotubes As the negative electrode active material of the supercapacitor, the composite material with the main component makes full use of the characteristics of the electrode material itself, can give full play to the potential of the positive and negative electrode materials, and forms a coordinated and complementary effect, thus forming a supercapacitor with high specific capacity and high specific energy. The hybrid supercapacitor with high stability and long cycle life not only has a significant outstanding effect on improving the performance of the supercapacitor, but also has a flexible composition that can meet people's different needs for capacitors under different conditions. No matter compared with carbon nanotube supercapacitors or polyaniline supercapacitors, polyaniline/carbon nanotube hybrid supercapacitors have higher specific energy and specific power. As shown in embodiment 1, comparative example 1 and 2, compare with carbon nanotube supercapacitor, the specific energy of polyaniline/carbon nanotube hybrid supercapacitor improves 135%, and average specific power improves 7%; Compared with the polyaniline supercapacitor, the specific energy of the polyaniline/carbon nanotube hybrid supercapacitor is increased by 30%, and the average specific power is increased by 100%. Compared with noble metal oxide supercapacitors, this new type of hybrid supercapacitor has the advantage of lower cost. In conclusion, polyaniline/carbon nanotube hybrid supercapacitor is a new type of supercapacitor with low cost and excellent performance.

Description of drawings

Figure 1 is a schematic diagram of the structure of a polyaniline/carbon nanotube hybrid supercapacitor.

Figure 2 is the charge-discharge curve of polyaniline/carbon nanotube hybrid supercapacitor.

Figure 3 is the charge and discharge curve of the polyaniline supercapacitor.

Figure 4 is the charge and discharge curve of the carbon nanotube supercapacitor.

Fig. 5 is a diagram of specific energy and specific power of polyaniline/carbon nanotube hybrid supercapacitor, polyaniline supercapacitor and carbon nanotube supercapacitor.

Detailed ways

The manufacturing process of the polyaniline/carbon nanotube hybrid supercapacitor provided by the present invention adopts the conventional method in the prior art, and the method generally includes 5 steps, the first step is to prepare the positive electrode current collector and the negative electrode current collector ; The second step is to prepare the positive electrode, that is, polyaniline electrode; the third step is to prepare the negative electrode, that is, the carbon nanotube electrode; the fourth step is to prepare the electrolyte and diaphragm; The positive electrode/electrolyte and the diaphragm/negative electrode/negative electrode current collector are assembled into a hybrid supercapacitor according to Figure 1.

The polyaniline positive electrode active material that the present invention adopts can adopt polyaniline single component, also can be to take polyaniline as main active component, add the composite material or mixed material that its mass percentage is less than 30% carbon material composition, so The carbon material mentioned above is one or more of carbon nanotubes, activated carbon, carbon fiber or acetylene black. The positive electrode active material can also be a copolymer of aniline and pyrrole, thiophene, or methylthiophene, or a blend of polyaniline, polypyrrole, polythiophene, and polymethylthiophene, and can also be added to the above-mentioned copolymer or blend. Carbon nanotubes, activated carbon, carbon fibers or acetylene black.

The negative electrode active material described in the present invention can be a material of pure carbon nanotubes, or a mixed material composed of carbon nanotubes as the main component and activated carbon, carbon fiber or acetylene black with a weight ratio of less than 30%. .

In order to meet people's different needs for supercapacitors under different conditions and to make supercapacitors have better performance, the mass ratio of positive electrode materials and negative electrode materials used in the present invention ranges from 0.1 to 5, and the optimal mass ratio ranges from 0.2 to 2. The specific mass ratio can be determined according to the principle that the capacity of the positive electrode material and the capacity of the negative electrode material are consistent.

The carbon nanotube negative electrode can be a carbon nanotube prepared by laser bombardment method, chemical vapor deposition method, glow discharge method, direct current arc discharge method, gas combustion method, catalyst high temperature pyrolysis method, etc., and by chemical Or carbon nanotubes treated by physical methods. It can also be a mixture of carbon nanotubes and activated carbon, carbon fiber, and acetylene black.

The present invention is described more fully below with reference to examples, however, the present invention can be implemented in many different ways, and the present invention should not be considered limited to the embodiments provided herein. Moreover, the purpose of providing these embodiments is to make the disclosure of the present invention thorough and complete, and to fully convey the idea of the present invention to those skilled in the art.

Example 1:

Mix the composite material of polyaniline and carbon nanotubes (containing 10% carbon nanotubes) and acetylene black evenly, add the acetone solution of PVDF-HFP dropwise, and apply it on the nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline and carbon nanotube composite material/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio).

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP (vinylidene fluoride-hexafluoropropylene copolymer) acetone solution dropwise, and apply it on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio).

With above-mentioned polyaniline electrode and carbon nanotube electrode as positive electrode and negative electrode respectively, with nickel foam as positive and negative electrode current collector, with 1mol/L LiPF ₆ (lithium hexafluorophosphate) EC/DEC (ethylene carbonate/butylene carbonate = 1 volume ratio) solution as the electrolyte, with Celgard2300 microporous membrane as the diaphragm, in an atmosphere filled with argon, assemble the positive current collector/polyaniline electrode/electrolyte and diaphragm/carbon nanotube electrode/negative current collector into polyaniline/carbon nanotube hybrid supercapacitors. The specific energy of the obtained capacitor can reach 6.8Wh/kg.

Example 2:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein polyaniline is 8.5 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 17mg of carbon nanotube.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 6.5 Wh/kg.

Example 3:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein polyaniline is 8.5 mg.

Mix carbon nanotubes, activated carbon and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain a carbon nanotube electrode. Wherein: carbon nanotube/activated carbon/acetylene black/PVDF-HFP=0.75/0.1/0.1/0.05 (mass ratio), wherein carbon nanotube and activated carbon are 25.5mg.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 6.6 Wh/kg.

Example 4:

Mix polyaniline, carbon fiber and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain a polyaniline electrode. Wherein: polyaniline/carbon fiber/acetylene black/PVDF-HFP=0.80/0.05/0.1/0.05 (mass ratio), wherein polyaniline is 8.0 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/carbon fiber/acetylene black/PVDF-HFP=0.80/0.05/0.1/0.05 (mass ratio), wherein the carbon nanotube is 32 mg.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 6.1 Wh/kg.

Example 5:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 1 mg of polyaniline.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 10 mg of carbon nanotube.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 2.8 Wh/kg.

Embodiment 6:

Mix polyaniline, activated carbon and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain a polyaniline electrode. Wherein: polyaniline/activated carbon/acetylene black/PVDF-HFP=0.80/0.05/0.1/0.05 (mass ratio), wherein polyaniline 16mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 8.5 mg of carbon nanotube.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 5.5 Wh/kg.

Embodiment 7:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain a polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein polyaniline is 25.5 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 8.5 mg of carbon nanotube.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 3.6 Wh/kg.

Embodiment 8:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein polyaniline is 34 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 8.5 mg of carbon nanotube.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 3.3 Wh/kg.

Embodiment 9:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein polyaniline is 42.5 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio), wherein 8.5 mg of carbon nanotube.

With the above-mentioned polyaniline electrode and carbon nanotube electrode as the positive and negative electrodes respectively, with nickel foam as the positive and negative electrode current collectors, with 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) The solution is used as the electrolyte, and the Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the positive electrode current collector/polyaniline positive electrode/electrolyte and the diaphragm/carbon nanotube negative electrode/negative electrode current collector are assembled into a polyaniline/ Carbon nanotube hybrid supercapacitor. The specific energy of the obtained capacitor was 2.8 Wh/kg.

Example 10:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.73/0.27/0.1 (mass ratio), wherein polyaniline is 7.3 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.73/0.27/0.1 (mass ratio), wherein the carbon nanotube is 7.3 mg.

With the above-mentioned polyaniline electrode as positive and negative poles, nickel foam as positive and negative current collectors, and 1mol/L tetraethylammonium tetrafluoroborate EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) solution As the electrolyte, Celgard2300 microporous membrane is used as the diaphragm. In an atmosphere filled with argon, the polyaniline superstructure is assembled according to the layers of positive electrode current collector/polyaniline positive electrode/electrolyte and separator/polyaniline negative electrode/negative electrode current collector. capacitor. The specific energy of the obtained capacitor was 6.3 Wh/kg.

Example 11:

Mix polyaniline and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and apply it on nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline/acetylene black/PVDF-HFP=0.95/0.05 (mass ratio), wherein polyaniline is 9.5 mg.

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotubes/acetylene black/PVDF-HFP=0.95/0.05 (mass ratio), wherein 9.5 mg of carbon nanotubes.

The above-mentioned polyaniline electrode is used as positive and negative electrodes, nickel foam is used as positive and negative electrode current collectors, 1mol/L tetraethylammonium tetrafluoroborate acetonitrile solution is used as electrolyte, Celgard2300 microporous membrane is used as diaphragm, and the electrode is filled with argon In an air atmosphere, a polyaniline supercapacitor is assembled according to the layers of positive electrode current collector/polyaniline positive electrode/electrolyte and separator/polyaniline negative electrode/negative electrode current collector. The specific energy of the obtained capacitor can reach 6Wh/kg.

Comparative Example 1:

Mix the composite material of polyaniline and carbon nanotubes (containing 10% carbon nanotubes) and acetylene black evenly, add the acetone solution of PVDF-HFP dropwise, and apply it on the nickel foam, press it, and dry it in vacuum to obtain polyaniline electrode. Wherein: polyaniline and carbon nanotube composite material/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio).

With the above-mentioned polyaniline electrode as the positive and negative electrodes, nickel foam as the positive and negative current collectors, and 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) solution as the electrolyte, and Celgard2300 microporous membrane is used as the diaphragm, and polyaniline supercapacitors are assembled according to the layers of positive electrode current collector/polyaniline electrode/electrolyte and separator/polyaniline electrode/negative electrode current collector in an atmosphere filled with argon. The specific energy of the obtained capacitor can reach 5.2Wh/kg.

It can be seen from Figures 2, 3 and 5 that under the discharge condition of a constant current of 17.6A/kg, the specific energy of the polyaniline supercapacitor is 5.24Wh/kg, and the average specific power is 90W/kg, while the polyaniline/carbon nanometer The specific energy of the tube hybrid supercapacitor is 6.83Wh/kg, and the average specific power is 180W/kg. Compared with the polyaniline supercapacitor, the specific energy of the polyaniline/carbon nanotube hybrid supercapacitor is increased by 30%, and the average ratio 100% more power.

Comparative example 2:

Mix carbon nanotubes and acetylene black evenly, add PVDF-HFP acetone solution dropwise, and spread on nickel foam, press and dry in vacuum to obtain carbon nanotube electrodes. Wherein: carbon nanotube/acetylene black/PVDF-HFP=0.85/0.1/0.05 (mass ratio).

With the above-mentioned carbon nanotube electrode as positive and negative electrodes, nickel foam as positive and negative current collectors, and 1mol/L LiPF ₆ EC/DEC (ethylene carbonate/butylene carbonate=1 volume ratio) solution as electrolyte, Using Celgard2300 microporous membrane as a diaphragm, in an atmosphere filled with argon, a carbon nanotube supercapacitor is assembled according to the layers of positive electrode current collector/carbon nanotube positive electrode/electrolyte and separator/carbon nanotube negative electrode/negative electrode current collector. The specific energy of the obtained capacitor can reach 3.2Wh/kg.

It can be seen from Figures 2, 4 and 5 that under the discharge condition of a constant current of 118A/kg, the specific energy of the carbon nanotube supercapacitor is 1.7Wh/kg, and the average specific power is 980kW/kg, while the polyaniline/carbon nanometer The specific energy of the tube hybrid supercapacitor is 4Wh/kg, and the average specific power is 1050W/kg. Compared with the carbon nanotube supercapacitor, the specific energy of the polyaniline/carbon nanotube hybrid supercapacitor is increased by 135%. 7% more power.

Claims (4)

1. A polyaniline/carbon nanotube hybrid supercapacitor, its structure contains positive electrode current collector, positive pole, electrolyte and diaphragm, negative pole and negative electrode current collector successively, it is characterized in that: described positive pole adopts polyaniline or It is made of a composite material composed of polyaniline and carbon material, and the carbon material is one or more of carbon nanotubes, activated carbon, carbon fiber or acetylene black, wherein the mass percentage of carbon material is less than 30%; the The negative electrode is made of carbon nanotubes or a mixture of carbon nanotubes and activated carbon, carbon fiber or acetylene black, wherein the mass percentage of activated carbon, carbon fiber or acetylene black is less than 30%. 2. The supercapacitor according to claim 1, characterized in that: the mass ratio of the positive electrode material to the negative electrode material is 0.1-5. 3. The supercapacitor according to claim 2, characterized in that: the mass ratio of the positive electrode material to the negative electrode material is 0.2-2. 4. The supercapacitor according to claim 1, wherein the electrolyte is LiPF ₆ , LiBF ₄ , LiClO ₄ , LiCF ₃ SO ₃ , (C ₂ H ₅ ) ₄ NPF ₆ , (C ₂ H ₅ ) ₄ NBF ₄ , (C ₂ H ₅ ) ₄ NClO ₄ , (C ₂ H ₅ ) ₄ NCF ₃ SO ₃ , (C ₄ H ₉ ) ₄ NPF ₆ , (C ₄ H ₉ ) ₄ NBF ₄ , (C ₄ H ₉ ) ₄ NClO ₄ , (C ₄ H ₉ ) ₄ NCF ₃ SO ₃ or their mixtures are used as electrolytes, and propylene carbonate, ethylene carbonate, butylene carbonate, acetonitrile or their mixtures are used as solvents.

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