Heat storage-heat and power cogeneration device and method based on thermal electron capacitance integrated energy storage and transduction

Abstract

The invention discloses a heat storage-heat and power cogeneration device and method based on thermal electron and capacitor integrated energy storage and transduction, and the device comprises a heat storage body, and a thermal electron emission unit and a capacitor energy storage unit which are located at the inner periphery of the heat storage body. The thermionic emission unit comprises a thermionic positive electrode located on the inner circumferential wall of the heat storage body and a negative electrode located on the inner circumference of the thermionic positive electrode, the capacitive energy storage unit comprises a negative electrode and a capacitive positive electrode located on the inner circumference of the negative electrode, and the thermionic emission unit and the capacitive energy storage unit share the same negative electrode. The thermal electron emission effect and the capacitance electricity storage are designed to be of an integrated structure and share the same negative electrode, heat storage, thermoelectric conversion and electricity storage are coupled into the same physical process, the structure is simple and compact, and the purposes of long-time large-capacity storage-discharge / heat with high energy density, high power density and transient response are achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energy storage, and particularly relates to a heat storage-heat and power cogeneration device and method based on heat electron capacitor integrated energy storage and energy conversion. BACKGROUND

[0002] With the increasing proportion of renewable energy and the intensification of power load fluctuation, the power system has an increasingly urgent demand for efficient, flexible and long-life energy storage and peak shaving technology. Existing energy storage technologies mainly include chemical energy storage, mechanical energy storage and thermal energy storage. Among them, thermal energy storage can realize large-scale and long-period energy storage, and has high system safety and low cost, but in the power output link, it needs to rely on heat engine cycle for heat-electricity conversion, and the energy conversion link is long and the response speed is slow, which is difficult to meet the transient power output demand. The heat electron emission technology is a physical method for directly converting heat energy into electricity, and has good high-temperature adaptability and few mechanical moving parts; however, the traditional heat electron power generation device usually only has instantaneous energy output function, and the power output is subject to the temperature of the heat storage body, which cannot effectively respond to the power demand, and the heat storage system is not formed into a compact integrated design, resulting in large equipment volume, low energy density and insufficient system integration. On the other hand, although physical energy storage devices such as supercapacitors have high power density and fast charging and discharging capability, their energy density is low and they are difficult to undertake long-time and large-capacity energy storage tasks.

[0003] Therefore, how to realize the integrated coupling of thermal energy storage, heat-electricity direct conversion and electric energy storage in the same physical structure, both retaining the long-time and large-capacity energy storage capability and having high power density and fast response characteristics, has become a technical problem to be solved in the current energy storage and heat and power cogeneration field. SUMMARY

[0004] In view of the deficiencies of the prior art, the application provides a heat storage-heat and power cogeneration device and method based on heat electron capacitor integrated energy storage and energy conversion, which is simple and compact in structure and diversified in function.

[0005] The technical scheme adopted by the application to solve the problems of the prior art is: a heat storage-heat and power cogeneration device based on heat electron capacitor integrated energy storage and energy conversion, comprising a heat storage body, a heat electron emission unit located at the inner periphery of the heat storage body and a capacitor energy storage unit, the heat storage body is a hollow cylindrical structure, the heat electron emission unit comprises a heat electron anode located at the inner peripheral wall of the heat storage body and a cathode located at the inner periphery of the heat electron anode, the capacitor energy storage unit comprises the cathode and a capacitor anode located at the inner periphery of the cathode, and the heat electron emission unit and the capacitor energy storage unit share the same cathode.

[0006] Further improvement scheme: the heat electron anode, the cathode and the capacitor anode are all hollow cylindrical structures, and the capacitor anode is a fin structure or a corrugated structure.

[0007] A further improvement is as follows: there is a gap between the thermionic positive electrode and the negative electrode, and a dielectric insulating layer is provided at both ends of the gap. The dielectric insulating layer is ceramic or glass, and the dielectric insulating layer seals the upper and lower ends of the gap.

[0008] A further improvement is that the dielectric insulating layer, the hot electron positive electrode, and the negative electrode are arranged to form a vacuum layer.

[0009] A further improvement is that a dielectric layer is provided between the negative electrode and the positive electrode of the capacitor, the dielectric layer has a thickness of 0.2 mm, and the dielectric layer is made of high dielectric constant ceramic.

[0010] A further improvement is that the center of the heat storage body also includes a gaseous working fluid, which is used for heat exchange.

[0011] A further improvement is as follows: the heat storage body is made of solid ceramic or high-temperature phase change material, and the thermionic positive electrode, the negative electrode and the capacitor positive electrode are made of metallic materials.

[0012] A further improvement is that the thermionic positive electrode and the capacitor positive electrode are electrically connected by a wire.

[0013] A further improvement is as follows: an electric heating coil is provided on the outer periphery of the heat storage body. The electric heating coil is electrically connected to an external power source and converts electrical energy into heat energy, thereby heating the heat storage body.

[0014] Another technical solution adopted by the present invention to solve the problem of the prior art is as follows: When the power demand is insufficient, the excess power in the power grid is transmitted to the heating coil and converted into the heat energy of the heat storage body by electric heating. The thermionic positive electrode is electrically connected to the positive electrode of the capacitor. Electrons in the positive electrode of the capacitor flow into the thermionic positive electrode through the wire. Under the action of the heat energy of the heat storage body, the free electrons in the thermionic positive electrode are transported to the negative electrode through the thermionic emission effect. Positive and negative charges accumulate on both sides of the dielectric layer, forming an electric field. The thermal energy of the heat body is converted into the electrical potential energy of the capacitor energy storage unit. When the power demand is high, the external load is connected, and the electrons of the negative electrode flow through the load and return to the positive electrode of the capacitor, outputting the electrical energy stored inside the capacitor energy storage unit. The electrons returning to the positive electrode of the capacitor flow through the wire to the thermionic positive electrode, and under the thermal energy drive of the heat storage body, they are emitted to the negative electrode, thus realizing the conversion of thermal energy into electrical energy output. When there is a heating demand, the external gaseous working fluid flows through the positive electrode of the capacitor, absorbing the waste heat of the thermionic electrons to raise the temperature, thereby realizing combined heat and power.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. High structural integration: The thermionic emission unit and the capacitor energy storage unit share the same negative electrode, avoiding the external circuit connection and energy transmission loss caused by the separate arrangement of traditional thermionic power generation and independent energy storage components, making the system compact, small in size and high in energy density.

[0017] 2. Combining long-term and transient energy storage and discharge: It utilizes thermal storage to achieve large-capacity, long-term energy storage, while leveraging the energy storage characteristics of capacitors to achieve rapid charging and discharging at the millisecond to second level, effectively meeting the peak-shaving and transient power requirements of the power grid.

[0018] 3. High power density and fast response: Thermionic emission directly drives the charging of the capacitor energy storage unit, reducing the energy conversion chain, enabling the system to achieve high power density output and respond quickly to fluctuations in power demand.

[0019] 4. Combined Heat and Power (CHP) Function: During the power generation process, the waste heat of the capacitor's positive plate can be recovered through a gaseous working fluid to achieve the heating function and improve the overall energy utilization rate of the system. Attached Figure Description

[0020] Figure 1 This is a three-dimensional schematic diagram of the thermal storage-cogeneration device based on the integrated thermionic capacitor energy storage and conversion of the present invention.

[0021] Figure 2 This is a top view of the thermal energy storage-cogeneration device based on the integrated thermal electronic capacitor energy storage and conversion of the present invention.

[0022] Figure 3 This is a partial cross-sectional view of the thermal energy storage-cogeneration device based on the integrated thermal electronic capacitor energy storage and conversion of the present invention.

[0023] Figure 4 This is a schematic diagram of the physical mechanism of the thermal energy storage-cogeneration device based on the integrated thermal electronic capacitor energy storage and conversion of the present invention. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the invention, and not all of them. Unless otherwise specified, the embodiments and features described in this application can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0025] It should be noted that if the embodiments of the invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0026] Furthermore, "multiple" refers to two or more. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the invention.

[0027] Please refer to Figures 1 to 4 As shown, a thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion includes a thermal energy storage body 1, a thermionic emission unit located on the inner periphery of the thermal energy storage body 1, and a capacitor energy storage unit. The thermal energy storage body 1 has a hollow cylindrical structure. The thermionic emission unit includes a thermionic positive electrode 2 located on the inner periphery of the thermal energy storage body 1 and a negative electrode 4 located on the inner periphery of the thermionic positive electrode 2. The capacitor energy storage unit includes a negative electrode 4 and a capacitor positive electrode 6 located on the inner periphery of the negative electrode 4. The thermionic emission unit and the capacitor energy storage unit share the same negative electrode 4, which avoids the external circuit connection and energy transmission loss caused by the separate arrangement of traditional thermionic power generation and independent energy storage elements, making the system compact, small in size, and high in energy density.

[0028] Furthermore, the thermionic positive electrode 2, the negative electrode 4, and the capacitor positive electrode 6 are all hollow cylindrical structures, and the capacitor positive electrode 6 has a finned or corrugated structure. All three are made of metallic materials. Optionally, the thermionic positive electrode 2 can be made of tungsten, molybdenum, LaB6, or a low work function material coated with an alkali metal to reduce the electron work function; the negative electrode 4 is made of a high-temperature resistant metallic material, such as tungsten.

[0029] Please see Figure 2 and Figure 3 As shown, there is a gap between the hot electron positive electrode 2 and the negative electrode 4. The upper and lower ends of the gap are provided with dielectric insulating layers 3, which are ceramic or glass. The dielectric insulating layers seal the upper and lower ends of the gap. The dielectric insulating layers 3, the hot electron positive electrode 2 and the negative electrode 4 together form a vacuum layer 10.

[0030] A dielectric layer 5 is located between the negative electrode 4 and the positive electrode 6 of the capacitor. The dielectric layer 5 has a thickness of 0.2 mm and is made of high dielectric constant ceramic.

[0031] The outer periphery of the heat storage body 1 is provided with an electric heating coil 9, which can be formed by winding nichrome wire. The electric heating coil 9 is electrically connected to an external power source and converts electrical energy into heat energy, thereby heating the heat storage body 1. The center of the heat storage body 1 also includes a gaseous working medium 7, which can be air, nitrogen, or other inert gases suitable for heat exchange. After the gaseous working medium 7 flows through the surface of the positive electrode 6 of the capacitor and absorbs the waste heat of the thermionic process, it can realize combined heat and power.

[0032] Furthermore, the heat storage body 1 can be selected from solid ceramics or high-temperature phase change materials (alumina-based ceramics, fluoride phase change media, etc.). The operating temperature range of the heat storage body 1 is 1000–2000℃, and the size is 100cm in diameter and 50cm in thickness. The electric heating coil 9 heats the heat storage body 1 by direct heating of the heating wire or by medium-frequency induction heating. The electric heating coil 9 converts the input power into heat energy and heats the heat storage body 1 to 1500℃.

[0033] The thermionic positive electrode 2 is located on one side of the heating area of ​​the heat storage body 1. The thermionic positive electrode 2 has a thickness of 1 mm and is electrically connected to the capacitor positive electrode 6 through the wire 8.

[0034] Please see Figure 4 As shown, the heating coil 9 heats the heat storage body 1, raising its temperature and increasing the temperature of the thermionic positive electrode 2. This allows free electrons to gain sufficient energy and be emitted through the vacuum gap in the vacuum layer 10 to the negative electrode 4, thereby forming a charge distribution on both sides of the dielectric layer 5, creating an electric field and storing potential energy. The negative electrode 4 is a tungsten plate, tightly attached to the back of the dielectric layer and serving as the negative terminal for power output. When there is a power demand, an external load is connected, and electrons in the negative electrode 4 flow through the load to the capacitor positive electrode 6. Simultaneously, under the heating of the heat storage body 1, electrons continue to be emitted, achieving synchronous output of thermal and electrical energy. When heating is required, the gaseous working fluid 7 flows through the fins or corrugated surface of the capacitor positive electrode 6. After absorbing the residual heat from the thermionic process, the gaseous working fluid 7 achieves combined heat and power. The flow velocity of the gaseous working fluid 7 is 0.5 m / s, and the direction of movement is from bottom to top. After heat exchange with the capacitor positive electrode 6, its temperature rises by approximately 80°C, making it suitable for direct heating or industrial preheating.

[0035] A thermal energy storage-cogeneration method based on integrated thermionic capacitor energy storage and conversion is disclosed. When power demand is insufficient, excess power from the grid is supplied to the heating coil 9 and converted into thermal energy in the thermal storage body 1 via electric heating. Thermionic positive electrode 2 is electrically connected to capacitor positive electrode 6. Electrons from capacitor positive electrode 6 flow into thermionic positive electrode 2 via wire 8. Under the thermal energy of the thermal storage body 1, free electrons in thermionic positive electrode 2 are transported to the negative electrode through thermionic emission effect. Positive and negative charges accumulate on both sides of the dielectric layer 5, forming an electric field. The thermal energy of 1 is converted into the potential energy of the capacitor energy storage unit. When the power demand is high, the external load is connected, and the electrons of the negative electrode 4 flow through the load and return to the positive electrode 6 of the capacitor, outputting the electrical energy stored inside the capacitor energy storage unit. The electrons returning to the positive electrode 6 of the capacitor flow through the wire 8 to the thermionic positive electrode 2. Driven by the thermal energy of the heat storage body 1, they are emitted to the negative electrode 4, thus realizing the conversion of thermal energy into electrical energy output. When there is a demand for heating, the external gaseous working fluid 7 flows through the positive electrode 6 of the capacitor, absorbing the waste heat of the thermionic electrons to raise the temperature, thereby realizing combined heat and power.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A thermal energy storage-combined heat and power (CHP) device based on integrated thermionic capacitor energy storage and conversion, characterized in that: The device includes a thermal storage body, a thermionic emission unit located on the inner periphery of the thermal storage body, and a capacitor energy storage unit. The thermal storage body has a hollow cylindrical structure. The thermionic emission unit includes a thermionic positive electrode located on the inner peripheral wall of the thermal storage body and a negative electrode located on the inner periphery of the thermionic positive electrode. The capacitor energy storage unit includes the negative electrode and a capacitor positive electrode located on the inner periphery of the negative electrode. The thermionic emission unit and the capacitor energy storage unit share the same negative electrode.

2. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion as described in claim 1, characterized in that: The thermionic positive electrode, the negative electrode, and the capacitor positive electrode are all hollow cylindrical structures. The thickness of the thermionic positive electrode is 1 mm, and the capacitor positive electrode is a finned structure or a corrugated structure.

3. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion as described in claim 1, characterized in that: There is a gap between the thermionic positive electrode and the negative electrode, and a dielectric insulating layer is provided at both ends of the gap. The dielectric insulating layer is ceramic or glass, and the dielectric insulating layer seals the upper and lower ends of the gap.

4. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion as described in claim 3, characterized in that: The dielectric insulating layer, the hot electron positive electrode, and the negative electrode surround to form a vacuum layer.

5. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion according to claim 1, characterized in that: A dielectric layer with a thickness of 0.2 mm is provided between the negative electrode and the positive electrode of the capacitor. The dielectric layer is made of high dielectric constant ceramic.

6. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion according to claim 1, characterized in that: The center of the heat storage body also includes a gaseous working fluid, which is used for heat exchange.

7. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion according to claim 1, characterized in that: The heat storage body is made of solid ceramic or high-temperature phase change material, and the thermionic positive electrode, the negative electrode and the capacitor positive electrode are all made of metallic materials.

8. The thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion according to claim 1, characterized in that: The thermionic positive electrode and the capacitor positive electrode are electrically connected by a wire.

9. The thermal energy storage-cogeneration device and method based on integrated thermionic capacitor energy storage and conversion according to claim 1, characterized in that: An electric heating coil is provided on the outer periphery of the heat storage body. The electric heating coil is electrically connected to an external power source and converts electrical energy into heat energy, thereby heating the heat storage body.

10. A thermal energy storage-cogeneration method based on integrated thermionic capacitor energy storage and conversion, applied to the thermal energy storage-cogeneration device based on integrated thermionic capacitor energy storage and conversion as described in any one of claims 1 to 9, characterized in that: When power demand is insufficient, excess power from the grid is supplied to the heating coil and converted into thermal energy of the heat storage body through electric heating. The thermionic positive electrode is electrically connected to the positive electrode of the capacitor. Electrons in the positive electrode of the capacitor flow into the thermionic positive electrode through the wire. Under the action of the thermal energy of the heat storage body, free electrons in the thermionic positive electrode are transported to the negative electrode through thermionic emission effect. Positive and negative charges accumulate on both sides of the dielectric layer, forming an electric field. The thermal energy of the heat storage body is converted into the potential energy of the capacitor energy storage unit. When power demand is high, an external load is connected. Electrons from the negative electrode flow through the load and return to the positive electrode of the capacitor, outputting the electrical energy stored inside the capacitor energy storage unit. Electrons returning to the positive electrode of the capacitor flow through the wire to the thermionic positive electrode. Driven by the thermal energy of the heat storage body, they are emitted to the negative electrode, thus realizing the conversion of thermal energy into electrical energy output. When there is a demand for heating, the external gaseous working fluid flows through the positive electrode of the capacitor, absorbing the waste heat of the thermionic electrons to raise the temperature, thereby realizing combined heat and power.

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