Thermoelectric energy storage device and power generation system

Abstract

The invention relates to the technical field of energy storage, and discloses a thermoelectric energy storage device and a power generation system. According to the thermoelectric energy storage device provided by the invention, the plurality of thermoelectric energy storage units are arranged in parallel and / or in series, so that the thermoelectric energy storage device can be flexibly deployed and expanded as required without depending on special geographical conditions and large-scale civil engineering, and can be directly transported and installed after being prefabricated in a factory, and the influence of site limitation on the energy storage device is reduced. Meanwhile, due to the fact that phase change heat storage has the characteristics of high energy density and low heat loss, a large amount of heat can be stably absorbed and released in the phase change process, temperature fluctuation is small, and the peak regulation requirements of intermittent energy sources such as wind power and photovoltaic energy are met.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, specifically to thermoelectric energy storage devices and power generation systems. Background Technology

[0002] Against the backdrop of a global energy transition towards renewable energy, the installed capacity of intermittent power sources such as wind and solar power has surged, leading to challenges such as increased supply and demand fluctuations and high curtailment rates in the power system. Energy storage technology, as a key component in balancing grid load and enhancing the absorption capacity of renewable energy, has become a core infrastructure supporting the stable operation of the new power system.

[0003] Traditional energy storage technologies mainly include pumped hydro storage and compressed air energy storage. Pumped hydro storage utilizes periods of surplus electricity to pump water to high-level reservoirs and releases the water to generate electricity during peak electricity demand periods. Compressed air energy storage, on the other hand, stores compressed air in underground caverns, and releases the energy to drive a turbine to generate electricity.

[0004] However, pumped hydro storage and compressed air energy storage technologies rely on specific geographical conditions, such as areas with abundant direct solar radiation and terrain differences, making them unsuitable for deployment in plains, arid regions, or urban areas. This results in geographical limitations and a lack of flexible deployment options. Summary of the Invention

[0005] In view of this, the present invention provides a thermoelectric energy storage device and a power generation system to solve the problem that traditional energy storage technologies are limited by geographical location, resulting in inflexible deployment.

[0006] In a first aspect, the thermoelectric energy storage device provided by the present invention includes multiple thermoelectric energy storage units arranged in parallel and / or series. These multiple thermoelectric energy storage units are connected through a unified power input interface and power output interface. Each thermoelectric energy storage unit includes a shell assembly, an electrothermal conversion element, and a phase change energy storage structure. The shell assembly includes an outer shell and an inner shell. The inner shell is installed inside the outer shell, and the inner shell and the outer shell are spaced apart to enclose independently arranged filling chambers and mounting chambers. The electrothermal conversion element is installed inside the mounting chamber and is used to connect to a power source and convert electrical energy into heat energy. The phase change energy storage structure includes a latent heat storage medium, having an energy storage state that receives heat generated by the electrothermal conversion element and stores it through high-density heat, and an energy release state that releases heat.

[0007] Beneficial effects: By arranging multiple thermoelectric energy storage units in parallel and / or series, flexible deployment and expansion are possible as needed, without relying on special geographical conditions or large-scale civil engineering. They can be directly transported and installed after factory prefabrication, significantly reducing the impact of site limitations on energy storage devices. Simultaneously, due to the high energy density and low heat loss characteristics of phase change thermal energy storage, it can stably absorb and release large amounts of heat during the phase change process with minimal temperature fluctuations, making it suitable for peak-shaving needs of intermittent energy sources such as wind and solar power. Furthermore, modular units can be easily deployed in renewable energy-rich areas or at grid absorption bottlenecks. When there is surplus electricity, the previously discarded wind and electricity can be converted into heat energy and stored in the phase change energy storage structure through the power input interface. During peak electricity demand or when renewable energy output is insufficient, the stored heat energy is released to drive a heat engine to generate electricity, which is then fed back to the grid through the power output interface, optimizing grid dispatch capabilities.

[0008] In one optional embodiment, the housing assembly includes an air inlet, a gas flow channel, and an air outlet, wherein the air inlet, the gas flow channel, and the air outlet are connected in sequence.

[0009] Beneficial effects: By forming an air inlet, gas flow channel and air outlet, the cold air is directly heated by the heat energy stored in the energy storage material inside the flow channel, forming high temperature and high pressure gas, which is used to do work and drive the generator to output electrical energy.

[0010] In one alternative embodiment, the gas flow channel has straight sections and curved sections, with at least two straight sections and adjacent straight sections connected in series through curved sections.

[0011] Beneficial effects: By setting at least two straight segments and connecting adjacent straight segments with curved segments, the air can undergo multiple direction changes during flow. The forced turning generated by the curved segments continuously disrupts the gas boundary layer and enhances turbulent mixing. Simultaneously, it extends the path length, enabling longer heat exchange paths within a limited space, prolonging the contact time between the gas and the latent heat storage medium, maximizing heat transfer, improving heat exchange efficiency, and meeting the needs of high-density deployment.

[0012] In one alternative embodiment, the housing assembly further includes a flow guide shell mounted on the curved section, the flow guide shell being used to guide gas from the end of one straight section to the beginning of another adjacent straight section.

[0013] Beneficial effects: By using a guide shell installed on the curved section, the gas at the end of the previous straight section can be directly guided to the beginning of the next adjacent straight section, avoiding local flow separation caused by sudden changes in airflow direction in the curved section, allowing the airflow to smoothly transition along the predetermined trajectory and reducing flow resistance.

[0014] In one alternative embodiment, the thermoelectric energy storage unit further includes a heat insulation element installed on the curved section and arranged close to the flow guide shell.

[0015] Beneficial effects: By installing the heat insulation component in the curved section, a physical isolation is formed. The heat insulation component directly blocks heat from dissipating to the external environment from the surface of the flow guide shell through heat conduction and heat radiation, significantly reducing heat loss along this path and lowering the overall energy consumption of the system.

[0016] In one optional embodiment, the phase change energy storage structure further includes a sensible heat storage medium, which stores heat through a sensible heat method; wherein, the sensible heat storage medium fixes the latent heat storage medium through capillary force.

[0017] Beneficial effects: Sensible heat storage media directly absorb and release heat through temperature changes, while latent heat storage media absorb and release a large amount of latent heat during phase change. This allows phase change energy storage structures to utilize the rapid response characteristics of sensible heat while achieving high energy density storage through latent heat. Simultaneously, the capillary force of the sensible heat storage media physically fixes the latent heat storage media within, avoiding leakage, movement, or delamination problems caused by thermal expansion and contraction or gravity in traditional phase change materials.

[0018] In one optional embodiment, the latent heat storage medium is a carbonate, and the sensible heat storage medium is magnesia.

[0019] Secondly, the present invention also provides a power generation system comprising an energy supply device, a thermoelectric energy storage device, and a power generation device. The thermoelectric energy storage device is the same as the thermoelectric energy storage device provided in the first aspect, wherein the thermoelectric energy storage device is used to receive and store energy supplied by the energy supply device; and the power generation device is used to receive the energy stored in the thermoelectric energy storage device and convert it into electrical energy.

[0020] Beneficial effects: Since the power generation system includes the thermoelectric energy storage device provided in the previous section, it has the same effect as the thermoelectric energy storage device, which will not be elaborated here.

[0021] In one optional embodiment, the energy supply device is a wind turbine generator to provide high-speed airflow; the thermoelectric energy storage device receives the high-speed airflow and outputs high-temperature air after heat exchange; the power generation device includes a heat exchanger, a turbine, and a condenser. The heat exchanger has a first loop and a second loop. The first loop receives the high-temperature air output by the thermoelectric energy storage device and outputs low-temperature air to the environment where the wind turbine generator is located after heat exchange. The second loop receives the low-temperature, low-pressure working fluid and outputs a high-temperature, high-pressure working fluid after heat exchange with the high-temperature air flowing through the first loop. The turbine receives the high-temperature, high-pressure working fluid and performs work to drive the generator to output electrical energy. The condenser receives the low-temperature, low-pressure working fluid output by the turbine and releases waste heat through condensation phase change, causing the working fluid to change from a gaseous state to a liquid state.

[0022] Beneficial effects: Wind turbines provide high-speed airflow to drive thermoelectric energy storage devices, enabling them to output high-temperature air. Simultaneously, the dual-loop design of the heat exchanger—the first loop handles the high-temperature air, and the second loop handles the working fluid—achieves efficient heat transfer and cascade utilization, reducing energy loss. The condenser releases waste heat through condensation phase change, causing the working fluid to change from a gaseous state to a liquid state and re-enter the system, forming a closed loop that maximizes waste heat recovery and improves overall energy efficiency. The thermoelectric energy storage device can store excess heat energy, releasing it during wind speed fluctuations or low wind speeds to compensate for the intermittent nature of wind power and ensure the continuous and stable output of the power generation system.

[0023] In one alternative embodiment, the power generation device further includes a waste heat recovery element for recovering waste heat and heating the phase change energy storage structure in the thermoelectric energy storage device.

[0024] Beneficial effects: By adding waste heat recovery components, the waste heat generated during power generation can be actively recovered and used to heat the phase change energy storage structure in the thermoelectric energy storage device. This converts the originally wasted energy into useful work, reduces the external energy input during the heating process, lowers operating costs, and improves the overall energy utilization rate of the power generation system. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a partial structural schematic diagram of the thermoelectric energy storage device provided in an embodiment of the present invention;

[0027] Figure 2 This is a cross-sectional view of a thermoelectric energy storage device provided in an embodiment of the present invention;

[0028] Figure 3 A partial structural diagram showing the holes in the thermoelectric energy storage device provided in this embodiment of the invention when it is a brick structure;

[0029] Figure 4 This is a schematic diagram of the power generation system provided in an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the structure of a power generation system provided in an embodiment of the present invention, where the energy supply device is a wind turbine and the power generation device includes a heat exchanger, a turbine, and a condenser.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Thermoelectric energy storage device; 11. Shell assembly; 111. Outer shell; 112. Inner shell; 113. Air inlet; 114. Gas flow channel; 115. Air outlet; 116. Straight section; 117. Bend section; 118. Flow guide shell; 12. Electrothermal conversion element; 13. Phase change energy storage structure; 14. Thermal insulation element;

[0033] 2. Energy supply equipment; 21. Wind turbine generator set;

[0034] 3. Power generation unit; 31. Heat exchanger; 311. First loop; 312. Second loop; 32. Turbine; 33. Condenser;

[0035] A. New energy; B. Off-peak electricity; C. Traditional energy; D. Air; E. Working fluid. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Against the backdrop of a global energy transition towards renewable energy, the installed capacity of intermittent power sources such as wind and solar power has surged, leading to challenges such as increased supply and demand fluctuations and high curtailment rates in the power system. Energy storage technology, as a key component in balancing grid load and enhancing the absorption capacity of renewable energy, has become a core infrastructure supporting the stable operation of the new power system.

[0038] Traditional energy storage technologies mainly include pumped hydro storage and compressed air energy storage. Pumped hydro storage utilizes periods of surplus electricity to pump water to high-level reservoirs and releases the water to generate electricity during peak electricity demand periods. Compressed air energy storage, on the other hand, stores compressed air in underground caverns, and releases the energy to drive a turbine to generate electricity.

[0039] However, pumped hydro storage and compressed air energy storage technologies rely on specific geographical conditions, such as areas with abundant direct sunlight and terrain differences, making them unsuitable for deployment in plains, arid areas, or urban areas. This results in geographical limitations and an inflexible deployment strategy.

[0040] Therefore, this invention utilizes phase change materials as a heat transfer and energy storage medium to convert off-peak electricity into thermal energy, achieving a low-cost and high-efficiency heat storage and release process. During the heat release process, a steam turbine generates electricity, realizing low-cost storage and conversion of electricity into heat and electricity. Compared with other energy storage technologies, the thermoelectric energy storage scheme of the phase change thermal energy storage-thermal power generation system constructed by this technical solution can be flexibly deployed without geographical limitations, making it an ideal long-term energy storage technology. Furthermore, it has minimal environmental impact and low cost during operation, helping to reduce the phenomenon of "wind and electricity curtailment".

[0041] The following is combined with Figures 1 to 5 The following describes embodiments of the present invention.

[0042] According to an embodiment of the present invention, in one aspect, the provided thermoelectric energy storage device 1 includes multiple thermoelectric energy storage units arranged in parallel and / or in series. The multiple thermoelectric energy storage units are connected through a unified power input interface and power output interface to achieve modular deployment and large-scale energy storage.

[0043] like Figure 1 As shown, any thermoelectric energy storage unit includes a housing assembly 11, an electrothermal conversion element 12, and a phase change energy storage structure 13.

[0044] The housing assembly 11 includes an outer shell 111 and an inner shell 112. The inner shell 112 is installed inside the outer shell 111. The inner shell 112 and the outer shell 111 are spaced apart to enclose an independently arranged filling chamber and an installation chamber. The electrothermal conversion element 12 is installed inside the installation chamber and is used to connect to the power supply and convert electrical energy into thermal energy. The phase change energy storage structure 13 includes a latent heat storage medium, and has an energy storage state that receives the heat generated by the electrothermal conversion element 12 and stores it through high-density heat, and an energy release state that releases heat.

[0045] This configuration allows for flexible deployment and expansion on demand by arranging multiple thermoelectric energy storage units in parallel and / or series. It does not rely on special geographical conditions and does not require large-scale civil engineering. The units can be directly transported and installed after being prefabricated in the factory, significantly reducing the impact of site limitations on the energy storage device.

[0046] Meanwhile, phase change thermal energy storage has the characteristics of high energy density and low heat loss, and can stably absorb and release a large amount of heat during the phase change process, such as high-temperature molten salt or composite phase change materials, and the temperature fluctuation is small, which is suitable for the peak shaving needs of intermittent energy sources such as wind power and photovoltaics.

[0047] In addition, modular units can be easily deployed in renewable energy-rich areas or grid absorption bottlenecks. When there is a power surplus (such as when strong winds or strong sunlight cause power generation to exceed immediate demand), the abandoned wind and electricity that would otherwise be discarded can be converted into heat energy and stored in the phase change energy storage structure 13 through the power input interface. When there is a peak in electricity demand or insufficient renewable energy supply, the stored heat energy can be released to drive the heat engine to generate electricity, and then the electricity can be fed back to the grid through the power output interface to optimize the grid dispatch capability.

[0048] It can be noted that the thermoelectric energy storage device 1 also includes a controller, which is communicatively connected to the electrothermal conversion element 12 to control the start-up, shutdown and operating power of the electrothermal conversion element 12 to adapt to the usage requirements of different working conditions.

[0049] It can be noted that the inner shell 112 is made of a porous material, which can increase the heat exchange rate. To save costs, it is made from waste metal slag or locally sourced materials (such as desert sand).

[0050] In one embodiment, such as Figure 1 and Figure 2 As shown, the housing assembly 11 includes an air inlet 113, a gas flow channel 114, and an air outlet 115, which are connected in sequence.

[0051] With this configuration, by forming an air inlet 113, a gas flow channel 114, and an air outlet 115, the cold air D is directly heated by the heat energy stored in the energy storage material inside the flow channel, forming a high-temperature and high-pressure gas, which is used to do work and drive the generator to output electrical energy.

[0052] In one embodiment, such as Figure 2 As shown, the gas flow channel 114 has a straight section 116 and a curved section 117. There are at least two straight sections 116, and two adjacent straight sections 116 are connected in series through the curved section 117.

[0053] With this configuration, by setting at least two straight segments 116 and connecting adjacent straight segments 116 with curved segments 117, the air D can undergo multiple reversals during the flow process. The forced reversal generated by the curved segments 117 continuously disrupts the gas boundary layer and enhances turbulent mixing.

[0054] At the same time, it can extend the path length, enabling a longer heat exchange path in a limited space, extending the contact time between the gas and the latent heat storage medium, fully transferring heat, improving heat exchange efficiency, and meeting the needs of high-density deployment.

[0055] In one embodiment, such as Figure 2 As shown, the housing assembly 11 also includes a flow guide shell 118, which is installed on the curved section 117 and is used to guide the gas at the end of one of the straight sections 116 to the beginning of another adjacent straight section 116.

[0056] With this configuration, by using the guide shell 118 installed on the curved section 117, the gas at the end of the previous straight section 116 can be directly guided to the beginning of the next adjacent straight section 116, avoiding local flow separation of the airflow due to sudden change in direction in the curved section 117, so that the airflow can smoothly transition along the predetermined trajectory and reduce flow resistance.

[0057] In one embodiment, it is still as follows Figure 2 As shown, the thermoelectric energy storage unit also includes a heat insulation element 14, which is installed on the curved section 117 and is arranged close to the flow guide shell 118.

[0058] With this configuration, by installing the heat insulation component 14 on the curved section 117 (near the flow guide shell 118), physical isolation is formed. The heat insulation component 14 directly blocks heat from dissipating to the external environment from the surface of the flow guide shell 118 through heat conduction and heat radiation, significantly reducing heat loss along this path and lowering the overall energy consumption of the system.

[0059] It can be noted that the phase change energy storage structure 13 also has a sensible heat storage medium, which stores heat through sensible heat; wherein, the sensible heat storage medium fixes the latent heat storage medium through capillary force.

[0060] With this configuration, the sensible heat storage medium directly absorbs and releases heat through temperature changes, while the latent heat storage medium absorbs and releases a large amount of latent heat during the phase change process. This allows the phase change energy storage structure 13 to utilize the rapid response characteristics of sensible heat and achieve high energy density storage through latent heat.

[0061] Meanwhile, through the capillary force of the sensible heat storage medium (such as the adsorption effect of porous materials), the latent heat storage medium is physically fixed inside, avoiding the leakage, movement or delamination problems caused by thermal expansion and contraction or gravity of traditional phase change materials.

[0062] Preferably, the latent heat storage medium is carbonate, and the sensible heat storage medium is magnesia.

[0063] During preparation, magnesium sand and carbonates are sintered into a brick structure.

[0064] With this configuration, carbonates serve as latent heat storage with high energy density, while magnesia serves as sensible heat storage with low energy density. By fixing the phase change material through capillary forces, a certain amount of heat storage can be provided, thereby increasing the overall energy storage density, reducing energy loss, and improving utilization efficiency.

[0065] It should be noted that carbonates are prone to sintering during high-temperature cycling, while the high hardness and chemical inertness of magnesia can serve as a skeletal structure to prevent carbonate particles from agglomerating.

[0066] Of course, in other alternative implementations, the reuse of waste resources is considered, and brick structures are made by pressing steel slag, chloride salts and nitrates.

[0067] It should be noted that the phase transition temperature of phase change materials exceeds 700℃.

[0068] It can be explained that, for example Figure 3 As shown, a hole structure is provided inside the brick structure. The electrothermal conversion element 12 is selected as a resistance wire. During installation, the resistance wire is embedded in the hole.

[0069] According to an embodiment of the present invention, in another aspect, a power generation system is also provided, such as... Figure 4 As shown, it includes an energy supply device 2, a thermoelectric energy storage device 1, and a power generation device 3.

[0070] Among them, the thermoelectric energy storage device 1 is the thermoelectric energy storage device 1 provided in the first aspect, which is used to receive and store the energy provided by the energy supply device 2; the power generation device 3 is used to receive the energy stored in the thermoelectric energy storage device 1 and convert it into electrical energy.

[0071] This configuration is made because the power generation system includes the thermoelectric energy storage device 1 provided in the previous section, which has the same effect as the thermoelectric energy storage device 1, and will not be described in detail here.

[0072] It should be noted that this embodiment does not impose specific limitations on the selection of the energy supply device 2.

[0073] For example, the energy supply device 2 can use new energy sources such as wind power and photovoltaics to directly supply energy to the thermoelectric energy storage device 1; it can also use traditional energy sources such as thermal power and thermoelectric power to heat the energy storage module using waste heat; of course, it can also use off-peak electricity B as the energy supply device 2 to directly supply energy to the thermoelectric energy storage device 1.

[0074] Preferably, such as Figure 4 and Figure 5 As shown, the energy supply device 2 is a wind turbine 21, which is used to provide high-speed airflow, and the thermoelectric energy storage device 1 is used to receive the high-speed airflow and output high-temperature air after heat exchange.

[0075] The power generation unit 3 includes a heat exchanger 31, a turbine 32, and a condenser 33.

[0076] Specifically: the heat exchanger 31 has a first loop 311 and a second loop 312. The first loop 311 is used to receive the high-temperature air output from the thermoelectric energy storage device 1 and output low-temperature air to the environment where the wind turbine 21 is located after heat exchange. The second loop 312 is used to receive the low-temperature and low-pressure working fluid and output the high-temperature and high-pressure working fluid after heat exchange with the high-temperature air flowing through the first loop 311. The turbine 32 is used to receive the high-temperature and high-pressure working fluid and do work to drive the generator to output electrical energy. The condenser 33 is used to receive the low-temperature and low-pressure working fluid output from the turbine 32 and release waste heat through condensation phase change, so that the working fluid E is converted from gaseous state to liquid state.

[0077] With this configuration, the wind turbine 21 provides high-speed airflow to drive the thermoelectric energy storage device 1, enabling it to output high-temperature air. Simultaneously, through the dual-loop design of the heat exchanger 31—the first loop 311 processes the high-temperature air, and the second loop 312 processes the working fluid E—efficient heat transfer and cascade utilization are achieved, reducing energy loss. The condenser 33 releases waste heat through condensation phase change, causing the working fluid E to change from a gaseous state to a liquid state and re-enter the system, forming a closed loop to maximize waste heat recovery and improve overall energy utilization. The thermoelectric energy storage device 1 can store excess heat energy and release it during wind speed fluctuations or low wind speeds, compensating for the intermittent nature of wind energy and ensuring the continuous and stable output of the power generation system.

[0078] It can be noted that the turbine 32 is selected as a steam turbine or a gas turbine, depending on actual needs such as energy conversion efficiency, cost, technological maturity, and safety risks. An air turbine device that matches the temperature of the heat exchanger 31 is selected.

[0079] It can be noted that the power generation device 3 also includes a waste heat recovery component, which is used to recover waste heat and to heat the phase change energy storage structure 13 in the thermoelectric energy storage device 1.

[0080] This configuration allows for the active recovery of waste heat generated during power generation by adding waste heat recovery components. This waste heat is then used to heat the phase change energy storage structure 13 in the thermoelectric energy storage device 1, converting the originally wasted energy into useful work. This reduces the external energy input during the heating process, lowers operating costs, and improves the overall energy utilization rate of the power generation system.

[0081] It can be explained that, during use, when the thermoelectric energy storage device 1 starts from room temperature, the temperature of the shell component 11 is first heated from room temperature to the minimum expected temperature, and then gradually heated to the threshold. During the period from peak electricity consumption to off-peak electricity consumption, the excess energy is used to heat the phase change energy storage structure 13, which is at room temperature, to the minimum expected temperature.

[0082] That is, the process of heating the phase change energy storage structure 13 from room temperature to the minimum expected temperature is completed in the early stage of the off-peak electricity conversion.

[0083] Specifically, heating the housing assembly 11 during off-peak electricity consumption periods (valley periods) can enable preheating of the phase change material.

[0084] This configuration allows the phase change energy storage structure 13 to be heated from room temperature to the minimum expected temperature in advance. That is, the actual heating process does not require a separate process of heating from room temperature to the minimum expected temperature. This enables the off-peak electricity B to directly heat the phase change energy storage structure 13 from its minimum expected temperature to the threshold temperature, reducing the heating time of the thermal storage bricks and fully utilizing the thermal energy, thus achieving efficient use of the energy used for heating.

[0085] It should be noted that the specific meanings of the terms such as high temperature, high pressure, low temperature, and low pressure mentioned above should be understood in conjunction with the context of the technical solution in which they are used. They represent a relatively improved or reduced state in the solution, and are not absolute numerical limitations.

[0086] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A thermoelectric energy storage device, characterized by, The thermal energy storage unit comprises a plurality of thermal energy storage units arranged in parallel and / or in series, the plurality of thermal energy storage units are connected through a unified power input interface and a power output interface, any thermal energy storage unit comprises: A shell assembly (11) comprising an outer shell (111) and an inner shell (112), the inner shell (112) is installed inside the outer shell (111), and the inner shell (112) is arranged in a spaced manner with the outer shell (111) to form an independently arranged filling chamber and a mounting chamber; An electrothermal conversion member (12) installed inside the mounting chamber for connecting a power supply and converting electrical energy into heat energy; A phase change energy storage structure (13) installed inside the filling chamber, the phase change energy storage structure (13) comprises a latent heat storage medium, has a heat storage state of receiving heat generated by the electrothermal conversion member (12) and storing heat at high density, and has a release state of releasing heat.

2. The thermal energy storage device according to claim 1, wherein The shell assembly (11) comprises an air inlet (113), a gas flow channel (114) and an air outlet (115), which are sequentially communicated.

3. The thermal energy storage device according to claim 2, wherein The gas flow channel (114) has a straight section (116) and a curved section (117), and at least two straight sections (116) are provided, and adjacent two straight sections (116) are connected in series through the curved section (117).

4. The thermal energy storage device according to claim 3, wherein The shell assembly (11) further comprises a flow guide shell (118), the flow guide shell (118) is installed on the curved section (117), and the flow guide shell (118) is used for guiding the gas at the end of one straight section (116) to the beginning of another adjacent straight section (116).

5. The thermal energy storage device according to claim 4, wherein The thermal energy storage unit further comprises: A heat insulation member (14) installed on the curved section (117), and the heat insulation member (14) is arranged close to the flow guide shell (118).

6. The thermal energy storage device according to any one of claims 1-5, wherein The phase change energy storage structure (13) further has a sensible heat storage medium, and the sensible heat storage medium stores heat in a sensible heat mode; Wherein, the sensible heat storage medium fixes the latent heat storage medium through capillary force.

7. The thermal energy storage device according to claim 6, wherein The latent heat storage medium is carbonate, and the sensible heat storage medium is magnesia.

8. A power generation system characterized by comprising: It comprises: An energy supply device (2); A thermal energy storage device (1) according to any one of claims 1-7, the thermal energy storage device (1) is used for receiving and storing energy provided by the energy supply device (2); A power generation device (3) for receiving the energy stored by the thermal energy storage device (1) and converting it into electrical energy.

9. The power generation system according to claim 8, wherein The energy supply device (2) is a wind turbine (21) used to provide high-speed airflow; The thermoelectric energy storage device (1) is used to receive high-speed airflow and output low-temperature air after heat exchange; The power generation device (3) includes: The heat exchanger (31) has a first loop (311) and a second loop (312). The first loop (311) is used to receive the high-temperature air output by the thermoelectric energy storage device (1) and output low-temperature air to the environment where the wind turbine (21) is located after heat exchange. The second loop (312) is used to receive the low-temperature and low-pressure working fluid and output the high-temperature and high-pressure working fluid after heat exchange with the high-temperature air flowing through the first loop (311). Turbine (32) is used to receive high-temperature and high-pressure working fluid and perform work to drive the generator to output electrical energy; The condenser (33) is used to receive the low-temperature and low-pressure working fluid output from the turbine (32) and release the waste heat through condensation phase change, so that the working fluid (E) is converted from gaseous to liquid state.

10. The power generation system according to claim 8, characterized in that, The power generation device (3) also includes: Waste heat recovery component, used to recover waste heat and use it to heat the phase change energy storage structure (13) in the thermoelectric energy storage device (1).

Images