CN111211000A

CN111211000A - Thermally charged supercapacitors with nanoparticle electrolytes

Info

Publication number: CN111211000A
Application number: CN202010015939.0A
Authority: CN
Inventors: 宣益民; 孟婷婷
Original assignee: Nanjing University of Aeronautics and Astronautics
Current assignee: Nanjing University of Aeronautics and Astronautics
Priority date: 2020-01-08
Filing date: 2020-01-08
Publication date: 2020-05-29
Anticipated expiration: 2040-01-08
Also published as: CN111211000B

Abstract

The invention discloses a thermally charged supercapacitor with nano-particle electrolyte, comprising electrodes, an electrolyte solution and a salt bridge, wherein the electrolyte solution contains nano-particles. The present invention can store electricity in the form of surface charges at the same time of thermoelectric conversion, and can charge and discharge at the same time. After adding the corresponding mass fraction of nanoparticles, the thermal diffusivity of the electrolyte ions can be greatly enhanced, the uniform distribution of the hot end temperature can be improved, and the performance of the thermally charged supercapacitor can be greatly improved.

Description

Thermally charged supercapacitor with nanoparticle electrolyte

Technical Field

The invention belongs to the field of thermoelectric conversion, and particularly relates to a thermal charging super capacitor using a nano particle electrolyte solution.

Background

With the large exploitation and consumption of fossil energy by human beings, the energy crisis gradually becomes the focus of international social attention. The utilization of various residual heat and solar heat is one of the important methods for improving energy structures and energy crisis. But is also an important challenge at the present stage. On one hand, the waste heat resources are everywhere and are not very sufficient, including waste heat in industrial production processes, waste heat of engines, solar heat and the like, if the waste heat resources can be harvested and utilized, the energy efficiency is greatly improved, and on the other hand, the thermoelectric conversion efficiency of the traditional technology is lower in the waste heat utilization efficiency no matter a direct method based on the Seebeck effect or an indirect method using an Organic Rankine Cycle (ORC) machine. A novel thermoelectric conversion device is proposed: the thermally charged supercapacitor can achieve high efficiency in waste heat utilization. The thermal charging super capacitor is composed of two traditional half super capacitors, and the two parts are respectively placed in electrolyte containers with different temperatures and connected through a salt bridge. The diffusion of ions is driven by the temperature difference, so that the surface charge density of the hot-end electrode is lower than that of the cold end, and a potential difference is generated. However, how to increase the finally obtained open-circuit voltage is a key problem for thermoelectric conversion utilization by the thermally charged super capacitor.

Disclosure of Invention

The invention aims to provide a thermal charging super capacitor of a nano particle electrolyte to improve the thermoelectric conversion performance of the thermal charging super capacitor.

In order to achieve the purpose, the invention adopts the technical scheme that:

a thermal charging super capacitor of a nanoparticle electrolyte comprises electrodes, an electrolyte solution and a salt bridge, wherein the electrolyte solution contains nanoparticles.

The electrolyte solution is composed of a base solution containing nanoparticles.

The nano particles are metal or nonmetal nano particles.

The nanoparticles are non-porous or porous nanoparticles.

The nanoparticles have thermal conductivity.

The particle size of the nanoparticles is 1-100 nm.

The base liquid is an organic system or an aqueous electrolyte solution.

In the electrolyte solution, the mass fraction of the nano particles is 0.01-30%.

Has the advantages that: the thermal charging super capacitor of the nano particle electrolyte can store electricity in the form of surface charge while performing thermoelectric conversion, and can be charged and discharged simultaneously. By adding the nano particles, not only the diffusion coefficient of ions is improved, but also the uniformity of temperature is improved. Compared with a system without adding the nano particle electrolyte, the open-circuit voltage is greatly improved, so that the performance of the thermal charging super capacitor in waste heat, industrial waste heat and solar heat utilization is improved.

Drawings

FIG. 1 is a schematic flow diagram of the present invention;

FIG. 2 is a schematic diagram of the present invention; in the figure: 1-nanoparticles, 2-thermal electrolyte solution, 3-cold electrolyte solution, 4-ion exchange membrane, 5-load;

FIG. 3 is the open circuit voltage of the system at different temperature differentials;

FIG. 4 is an open circuit voltage of a system with the same mass fraction of nanocarbon and nanocopper added;

fig. 5 shows the open circuit voltage of the system with different mass fractions of nanocarbon added at different temperature differences.

Detailed Description

The invention is further explained below with reference to the drawings.

The principle of the nanoparticle electrolyte thermally charged supercapacitor of the present invention is shown in fig. 1 and 2, and the nanoparticle electrolyte thermally charged supercapacitor can store electricity as surface charges while performing thermoelectric conversion, and can be charged and discharged simultaneously. By adding the nano particles, on one hand, the diffusion coefficient of ions is improved, more ions move from the hot end to the cold end under the driving of temperature difference, so that the surface charge density of the hot end electrode is lower than that of the cold end electrode, a larger potential difference is generated, and a higher system open-circuit voltage is obtained; on the other hand, the response time of the temperature is prolonged, so that the time for the hot end temperature to reach stability is shortened, the hot end temperature is uniformly distributed, the charging time is shortened, and the charging and discharging speed is increased. Thereby improving the performance of the system in waste heat, industrial waste heat and solar heat utilization.

Fig. 2 shows a typical nanoparticle electrolyte thermally charged supercapacitor of the present invention, which includes a thermal electrolyte solution 2 and a cold electrolyte solution 3, wherein the thermal electrolyte solution 2 and the cold electrolyte solution 3 both contain nanoparticles 1, an ion exchange membrane 4 is disposed between the thermal electrolyte solution 2 and the cold electrolyte solution 3, electrodes are disposed in the thermal electrolyte solution 2 and the cold electrolyte solution 3, and a load 5 is connected between the electrodes through a lead.

In the invention, different types of nanoparticles and different mass fractions of nanoparticles are added to obtain different ion diffusion coefficients of the electrolyte solution, so that open-circuit voltages of the system under different conditions and at different temperature differences are obtained, and the invention is verified through the following experiments.

Example 1:

the thermal charging super capacitor of the nano particle electrolyte comprises the following specific embodiments:

respectively placing two traditional semi-super capacitors in a container filled with electrolyte solution, heating the container at one end, and setting the temperature of a cold end to be T₁Hot end temperature of T₂By changing T₁And T₂Different temperature differences can be obtained. And when the temperature difference is stable, reading the open-circuit voltage of the system at different temperature differences. The results show that the larger the temperature difference, the larger the open circuit voltage measured by the system is as shown in fig. 3.

Example 2:

respectively placing two traditional semi-super capacitors in a container filled with electrolyte solution, heating the container at one end, and setting the temperature of a cold end to be T₁Hot end temperature of T₂By changing T₁And T₂Different temperature differences can be obtained. And when the temperature difference is stable, reading the open-circuit voltage of the system at different temperature differences. Respectively adding the same mass into hot-end electrolyte solution

Comparing the open circuit voltage obtained by the system without the nano particles with the open circuit voltage obtained by the system with the nano copper>System for adding nano carbon>The system without added nanoparticles is shown in FIG. 4.

Example 3:

two conventional semi-supercapacitors are placed in respective containers filled with an electrolyte solution,heating a container at one end, wherein the temperature of a cold end is T₁Hot end temperature of T₂By changing T₁And T₂Different temperature differences can be obtained. And when the temperature difference is stable, the open-circuit voltage of the system under different temperature differences is read by using the data acquisition system. Respectively adding the mass fraction of the hot-end electrolyte solution

And

the obtained open circuit voltage for different nanoparticle concentrations and different temperature differences is shown in fig. 5. There is an optimum value of 0.7% for the mass fraction of nanoparticles added. Because the diffusion coefficient of ions increases with the addition of nanoparticles at lower nanoparticle concentrations and decreases with the addition of nanoparticles at higher nanoparticle concentrations.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A thermal charging supercapacitor of a nanoparticle electrolyte, characterized in that: the electrode comprises an electrode, an electrolyte solution and a salt bridge, wherein the electrolyte solution contains nano particles.

2. The nanoparticle electrolyte thermally charged supercapacitor according to claim 1, wherein: the electrolyte solution is composed of a base solution containing nanoparticles.

3. The nanoparticle electrolyte thermally charged supercapacitor according to claim 1 or 2, wherein: the nano particles are metal or nonmetal nano particles.

4. The nanoparticle electrolyte thermally charged supercapacitor according to claim 1 or 2, wherein: the nanoparticles are non-porous or porous nanoparticles.

5. The nanoparticle electrolyte thermally charged supercapacitor according to claim 1 or 2, wherein: the nanoparticles have thermal conductivity.

6. The nanoparticle electrolyte thermally charged supercapacitor according to claim 1 or 2, wherein: the particle size of the nanoparticles is 1-100 nm.

7. The nanoparticle electrolyte thermally charged supercapacitor according to claim 2, wherein: the base liquid is an organic system or an aqueous electrolyte solution.

8. The nanoparticle electrolyte thermally charged supercapacitor according to claim 1, wherein: in the electrolyte solution, the mass fraction of the nano particles is 0.01-30%.