A power storage system

Abstract

The present application proposes an electricity storage system, comprising: an electricity storage circuit, comprising an energy storage reservoir, a first compressor, a first heat exchanger, a first phase change device for changing the phase of an energy storage medium from a gaseous state to a liquid state, a first throttle valve and an energy storage reservoir, so that the energy storage medium enters the energy storage reservoir after being compressed, cooled, liquefied and throttled, and the liquid energy storage medium in the energy storage reservoir is caused to change phase to a solid energy storage medium, so as to realize the conversion of electric energy into cold energy; a discharge circuit, comprising an energy storage reservoir, a power device, a second phase change device for changing the phase of an energy storage medium from a liquid state to a gaseous state, a second heat exchanger, a first expander, a cooler and an energy storage reservoir, so that the energy storage medium is used to generate electricity by utilizing the pressurization, gasification, overheating, expansion and cooling process to return to the energy storage reservoir, so as to realize the conversion of cold energy into electric energy.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to an electricity storage system. Background Art

[0002] Gas compression energy storage technology based on the principle of thermal power cycle has the advantages of safety, environmental protection, high efficiency and flexibility. It is suitable for large-scale power energy storage and has broad development prospects. However, air compression energy storage and carbon dioxide compression energy storage have high working pressure, large gas storage capacity, high investment cost, and certain requirements for site conditions. Liquefied air energy storage uses a deep cold liquefaction process to store liquid air, but the irreversible loss in the energy storage cycle process is large, and low-temperature cold storage technology is also required, which is not cost-effective. Other heat pump-type power storage solutions require specific working fluids and suitable cold storage materials. The heat exchange process of cold storage and release has large irreversible losses, the cycle process is complex, and the energy storage efficiency is not satisfactory. It is still in the conceptual research and development stage and cannot reach the level of industrial application. Summary of the invention

[0003] In view of this, the present application provides an electricity storage system, the selected energy storage medium of which can directly store and release cold by phase change in the coexistence of gas, liquid and solid. The cold storage and release process does not require heat exchange equipment, has small irreversible losses and high energy storage efficiency.

[0004] In order to achieve the above objectives, this application provides the following technical solutions:

[0005] A power storage system, comprising:

[0006] The power storage circuit comprises an energy storage reservoir, a first compressor, a first heat exchanger, a first phase change device for changing the energy storage medium from a gaseous state to a liquid state, a first throttle valve and the energy storage reservoir, which are connected in series in sequence, so that the energy storage medium is compressed, cooled, liquefied, throttled and then returns to the energy storage reservoir, so that the liquid energy storage medium in the energy storage reservoir is phase-changed to a solid energy storage medium, so as to realize the conversion of electric energy into cold energy;

[0007] A discharge circuit comprises the energy storage reservoir, a power device, a second phase change device for changing the energy storage medium from a liquid state to a gaseous state, a second heat exchanger, a first expander, a cooler and the energy storage reservoir, which are sequentially connected in series, so as to utilize the pressurization, gasification, overheating, expansion and cooling process of the energy storage medium to generate electricity and then return to the energy storage reservoir, thereby causing the solid energy storage medium in the energy storage reservoir to change into a liquid energy storage medium, so as to realize the conversion of cold energy into electrical energy;

[0008] The energy storage reservoir is used to store energy storage media in a gas, liquid and solid coexisting state, and the energy storage medium can undergo a transition between gas, liquid and solid states.

[0009] Optionally, the above energy storage system further includes a first electricity storage shunt pipeline.

[0010] The first electricity storage shunt pipeline is connected in series with a second compressor, a condenser, and a second throttle valve in sequence. The inlet of the second compressor is connected to the outlet of the first heat exchanger, and the outlet of the second throttle valve is connected to the energy storage tank.

[0011] Optionally, the above energy storage system further includes an electric storage heat exchanger, wherein the electric storage heat exchanger includes:

[0012] a first electricity storage and heat exchange pipeline, used for connecting the energy storage reservoir and the first compressor;

[0013] a second electricity storage heat exchange pipeline for performing heat exchange with the first electricity storage heat exchange pipeline, wherein the second electricity storage heat exchange pipeline is used to communicate with the condenser and the second throttle valve;

[0014] The energy storage medium in the first electricity storage and heat exchange pipeline absorbs the heat of the energy storage medium in the second electricity storage and heat exchange pipeline to cool the energy storage medium entering the second throttle valve.

[0015] Optionally, the above energy storage system further includes a discharge heat exchanger, wherein the discharge heat exchanger includes:

[0016] A first discharge heat exchange pipeline, used for connecting the power device and the second phase change device;

[0017] a second discharge heat exchange pipeline for performing heat exchange with the first discharge heat exchange pipeline, wherein the second discharge heat exchange pipeline is used to connect the cooler and the energy storage reservoir;

[0018] The energy storage medium in the second discharge heat exchange pipeline releases heat to the energy storage medium in the first discharge heat exchange pipeline, so as to reduce the temperature of the energy storage medium entering the energy storage reservoir.

[0019] Optionally, the above energy storage system further includes a first cold tank and a first hot tank;

[0020] Among them, in the power storage stage, the first heat exchanger absorbs the compression heat of the energy storage medium and transfers the compression heat to the heat exchange medium output from the first cold tank to the first hot tank; in the discharge stage, the heat exchange medium is output from the first hot tank to the first cold tank and transfers the heat to the energy storage medium in the second heat exchanger.

[0021] Optionally, the above energy storage system further includes:

[0022] a third heat exchanger disposed between the first phase change device and the first throttle valve;

[0023] a fourth heat exchanger disposed between the power device and the second phase change device;

[0024] a second cold tank and a second hot tank;

[0025] Among them, in the power storage stage, the third heat exchanger cools the energy storage medium and transfers the cold energy in the heat exchange medium output from the second cold tank to the second hot tank to the energy storage medium; in the discharge stage, the heat exchange medium is output from the second hot tank to the second cold tank, and absorbs the cold energy of the energy storage medium through the fourth heat exchanger.

[0026] Optionally, the energy storage system further includes a second electricity storage shunt pipeline, the inlet of the second electricity storage shunt pipeline is connected to the outlet of the first phase change device, and the electricity storage heat exchanger further includes a third electricity storage heat exchange pipeline for heat exchange with the first electricity storage heat exchange pipeline;

[0027] The second electricity storage shunt pipeline is connected in series with the third electricity storage heat exchange pipeline, and the third electricity storage heat exchange pipeline is connected in parallel with the third heat exchanger to adjust the heat exchange balance.

[0028] Optionally, in the above energy storage system, the discharge circuit includes an inlet and an outlet connected to the energy storage reservoir, and the inlet is located below the liquid level formed by the liquid energy storage medium to allow the gaseous energy storage medium to be fully mixed with the liquid energy storage medium; and / or,

[0029] The power storage circuit includes an air outlet and a liquid inlet connected to the energy storage reservoir, the air outlet is arranged at the top of the energy storage reservoir, and the liquid inlet is arranged above the liquid level formed by the energy storage medium;

[0030] And / or, a second expander is provided between the discharge heat exchanger and the energy storage reservoir.

[0031] Optionally, the above energy storage system further includes a first pressure energy collection device and a second pressure energy collection device;

[0032] The third heat exchanger comprises an outflow port for the energy storage medium to flow out, and the outlet of the third electricity storage and heat exchange pipeline and the outflow port are both connected to the inlet of the first pressure energy collection device through a pipeline;

[0033] The second pressure energy collection device is arranged between the outlet of the second electricity storage and heat exchange pipeline and the inlet of the second throttle valve.

[0034] Optionally, the above-mentioned energy storage system also includes a heat exchange structure for enabling the first phase change device and the second phase change device to exchange heat, the heat exchange structure can absorb the heat released by the first phase change device, and can use the absorbed heat to heat the second phase change device, the heat exchange structure, the first phase change device and the second phase change device are integrated into a phase change cold storage heat exchanger with an integrated structure.

[0035] The present application provides a power storage system, in which the energy storage medium stored in the energy storage reservoir is in a gas, liquid, and solid coexistence state. In the power storage stage, the energy storage medium is compressed, cooled, liquefied, and throttled in the power storage circuit before returning to the energy storage reservoir, causing the liquid energy storage medium in the energy storage reservoir to change phase to a solid energy storage medium, so as to realize the conversion of electric energy into cold energy; in the discharge stage, the expansion process of the energy storage medium is used to generate electricity and then returns to the energy storage reservoir, causing the solid energy storage medium in the energy storage reservoir to change phase to a liquid energy storage medium, so as to realize the conversion of cold energy into electric energy. In this way, the energy storage medium is directly used as a low-temperature phase-change cold storage material to perform phase change between gas, liquid, and solid states to store or release cold. The cold storage or release process does not require heat exchange equipment, has small irreversible losses, and has high energy storage efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0037] Figure 1 A schematic diagram of a power storage system provided in an embodiment of the present application.

[0038] 1. Energy storage tank; 2. First compressor; 3. First heat exchanger; 4. First phase change device; 5. First throttle valve; 6. Power device; 7. Second phase change device; 8. Second heat exchanger; 9. First expander; 10. Cooler; 11. Second compressor; 12. Condenser; 13. Second throttle valve; 14. Electricity storage heat exchanger; 15. Discharge heat exchanger; 16. First cold tank; 17. First hot tank; 18. Third heat exchanger; 19. Fourth heat exchanger; 20. Second cold tank; 21. Second hot tank; 22. Second expander; 23. First pressure energy collection device; 24. Second pressure energy collection device; 25. Heat exchange structure. DETAILED DESCRIPTION

[0039] The present application provides an electricity storage system, wherein the selected energy storage medium can directly store or release cold through phase change in a gas, liquid, or solid coexistence state, and the cold storage or release process does not require heat exchange equipment, has a small irreversible loss, and has a high energy storage efficiency.

[0040] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0041] like Figure 1 As shown, the embodiment of the present application provides a power storage system, including a power storage circuit and a discharge circuit. Preferably, during valley power, the power storage circuit is controlled to operate to store electric energy; during peak power, the discharge circuit is controlled to operate to release electric energy, so as to make full use of the dividend of valley power and obtain good benefits.

[0042] Specifically, when the power storage circuit is running, the gaseous energy storage medium flows out of the energy storage reservoir 1 and flows through the first compressor 2, the first heat exchanger 3, the first phase change device 4, and the first throttle valve 5 in sequence, wherein the gaseous energy storage medium changes into liquid in the first phase change device 4, i.e., in the power storage stage, the energy storage medium returns to the energy storage reservoir 1 after being compressed, cooled, liquefied, and throttled.

[0043] It should be noted that the energy storage medium in the energy storage reservoir 1 is in a gas, liquid and solid coexistence state, and the energy storage medium can be transformed between gas, liquid and solid states.

[0044] More specifically, before the electricity storage process begins, the energy storage medium in the energy storage reservoir 1 is mainly in liquid state, and the gaseous energy storage medium flows out of the energy storage reservoir 1, causing the thermodynamic equilibrium state between the gas, liquid and solid in the energy storage reservoir 1 to change, and the liquid energy storage medium in the energy storage reservoir 1 dynamically changes phases into gaseous and solid states. At the same time, the energy storage medium returns to the energy storage reservoir 1 after the electricity storage circuit is completed. In addition to maintaining the mass conservation of the energy storage medium in the energy storage reservoir 1, it is also used to provide cold energy to the energy storage reservoir 1, so that the proportion of solid energy storage medium in the energy storage reservoir 1 can be continuously increased, realizing the conversion of electrical energy into low-temperature cold energy.

[0045] When the discharge loop is running, the energy storage medium flows out of the energy storage reservoir 1 and flows through the power device 6, the second phase change device 7, the second heat exchanger 8, the first expander 9, and the cooler 10 in sequence, wherein the liquid energy storage medium in the second phase change device 7 changes into a gaseous state, i.e., in the discharge stage, the energy storage medium returns to the energy storage reservoir 1 after being pressurized, gasified, overheated, expanded to generate electricity, and cooled. More specifically, the liquid energy storage medium flows out of the energy storage reservoir 1, causing the thermodynamic equilibrium state between the gas, liquid, and solid in the energy storage reservoir 1 to change, and the gaseous and solid energy storage medium in the energy storage reservoir 1 dynamically changes into a liquid state. At the same time, the energy storage medium returns to the energy storage reservoir 1 after the discharge loop is completed. In addition to maintaining the mass conservation of the energy storage medium in the energy storage reservoir 1, it is also used to obtain cold energy from the energy storage reservoir 1, so that the proportion of solid energy storage medium in the energy storage reservoir 1 can be continuously reduced, realizing the conversion of low-temperature cold energy into electrical energy, and finally returning to the initial state dominated by liquid.

[0046] From the above, it can be seen that the energy storage medium is directly used as a low-temperature phase-change cold storage material to directly phase-change cold storage or release cold in the coexistence of gas, liquid and solid. The cold storage or release process does not require heat exchange equipment, has small irreversible losses and high energy storage efficiency.

[0047] It should be noted that, in the present application, preferably, the energy storage medium is ammonia.

[0048] Furthermore, the power storage system also includes a first power storage shunt pipeline, on which a second compressor 11, a condenser 12, and a second throttle valve 13 are sequentially connected in series, the inlet of the second compressor 11 is connected to the outlet of the first heat exchanger 3, and the outlet of the second throttle valve 13 is connected to the energy storage reservoir 1. It can be understood that the second compressor 11, the condenser 12, and the second throttle valve 13 connected in series form a parallel relationship with the first phase change device 4 and the first throttle valve 5 connected in series, that is, the energy storage medium is shunted after flowing through the first heat exchanger 3, a part of which enters the first power storage shunt pipeline, and returns to the energy storage reservoir 1 after compression, liquefaction, and throttling, and the other part flows through the first phase change device 4 to undergo a gas-liquid phase change and returns to the energy storage reservoir 1 after throttling and reducing the pressure. The setting of the first power storage shunt pipeline bears part of the energy storage medium, and the path of the first power storage shunt pipeline is shorter, that is, the energy storage medium can return to the energy storage reservoir 1 faster, thereby improving the power storage efficiency.

[0049] In addition, the power storage system also includes a power storage heat exchanger 14, which includes: a first power storage heat exchange pipeline for connecting the energy storage reservoir 1 and the first compressor 2; a second power storage heat exchange pipeline for heat exchange with the first power storage heat exchange pipeline, and the second power storage heat exchange pipeline is used to connect the condenser 12 and the second throttle valve 13; wherein the energy storage medium in the first power storage heat exchange pipeline absorbs the heat of the energy storage medium in the second power storage heat exchange pipeline to cool the energy storage medium entering the second throttle valve 13. It can be seen that the setting of the power storage heat exchanger 14 realizes heat exchange between energy storage media and makes full use of energy.

[0050] In some optional embodiments, the power storage system further includes a discharge heat exchanger 15, which includes: a first discharge heat exchange pipeline for connecting the power device 6 and the second phase change device 7; a second discharge heat exchange pipeline for heat exchange with the first discharge heat exchange pipeline, and the second discharge heat exchange pipeline is used to connect the cooler 10 and the energy storage reservoir 1; wherein the energy storage medium in the second discharge heat exchange pipeline releases heat to the energy storage medium in the first discharge heat exchange pipeline, so as to reduce the temperature of the energy storage medium entering the energy storage reservoir 1. It can be seen that the setting of the discharge heat exchanger 15 realizes heat exchange between energy storage media, and ensures the stability of the energy storage medium in the energy storage reservoir 1 while improving energy utilization.

[0051] In some optional embodiments, the power storage system also includes a first cold tank 16 and a first hot tank 17; wherein, in the power storage stage, the first heat exchanger 3 absorbs the compression heat of the energy storage medium and transfers the compression heat to the heat exchange medium output from the first cold tank 16 to the first hot tank 17; in the discharge stage, the heat exchange medium is output from the first hot tank 17 to the first cold tank 16, and transfers the heat to the energy storage medium in the second heat exchanger 8.

[0052] The connection relationship between the first cold tank 16, the first hot tank 17, the first heat exchanger 3 and the second heat exchanger 8 is more specifically that the first heat exchanger 3 includes a first heat exchange pipeline, and the second heat exchanger 8 includes a second heat exchange pipeline; the inlet of the first cold tank 16 is connected to the outlet of the second heat exchange pipeline, the outlet of the first cold tank 16 is connected to the inlet of the first heat exchange pipeline, the inlet of the first hot tank 17 is connected to the outlet of the first heat exchange pipeline, and the outlet of the first hot tank 17 is connected to the inlet of the second heat exchange pipeline. The arrangement of the first cold tank 16 and the first hot tank 17 allows the heat released by the power storage circuit to be absorbed and utilized by the discharge circuit, thereby improving the thermal efficiency of the power storage circuit and the discharge circuit.

[0053] It should be noted that the heat exchange medium of the first cold tank 16 and the first hot tank 17 may be, but is not limited to, water, heat transfer oil, etc.

[0054] The power storage system also includes: a third heat exchanger 18 arranged between the first phase change device 4 and the first throttle valve 5; a fourth heat exchanger 19 arranged between the power device 6 and the second phase change device 7; a second cold tank 20 and a second hot tank 21; wherein, in the power storage stage, the third heat exchanger 18 cools the energy storage medium and transfers the cold energy in the heat exchange medium output from the second cold tank 20 to the second hot tank 21 to the energy storage medium; in the discharge stage, the heat exchange medium is output from the second hot tank 21 to the second cold tank 20, and absorbs the cold energy of the energy storage medium through the fourth heat exchanger 19.

[0055] The connection relationship between the second cold tank 20, the second hot tank 21, the third heat exchanger 18 and the fourth heat exchanger 19 is more specifically that the inlet of the second cold tank 20 is connected to the outlet of the fourth heat exchange pipeline, the outlet of the second cold tank 20 is connected to the inlet of the third heat exchange pipeline, the inlet of the second hot tank 21 is connected to the outlet of the third heat exchange pipeline, and the outlet of the second hot tank 21 is connected to the inlet of the fourth heat exchange pipeline. The arrangement of the second cold tank 20 and the second hot tank 21 allows the cold released by the discharge circuit to be absorbed and utilized by the power storage circuit, thereby improving the thermal efficiency of the power storage circuit and the discharge circuit.

[0056] It should be noted that the heat exchange medium between the second cold tank 20 and the second hot tank 21 may be, but is not limited to, an organic solution, liquid organic matter, and the like.

[0057] Furthermore, the power storage system further includes a second power storage shunt pipeline, the inlet of the second power storage shunt pipeline is connected to the outlet of the first phase change device 4, and the power storage heat exchanger 14 further includes a third power storage heat exchange pipeline for heat exchange with the first power storage heat exchange pipeline; the second power storage shunt pipeline is connected in series with the third power storage heat exchange pipeline, and the third power storage heat exchange pipeline is connected in parallel with the third heat exchanger 18. The second power storage shunt pipeline is provided to bear part of the flow of the energy storage medium, and thus the heat exchange balance is adjusted.

[0058] In some optional embodiments, the discharge circuit includes an inlet and an outlet connected to the energy storage reservoir 1, and the inlet is located below the liquid level formed by the liquid energy storage medium to allow the gaseous energy storage medium and the liquid energy storage medium to be fully mixed; and / or, the power storage circuit includes an air outlet and a liquid inlet connected to the energy storage reservoir 1, and the air outlet is arranged at the top of the energy storage reservoir 1, and the liquid inlet is arranged above the liquid level formed by the energy storage medium.

[0059] And / or, a second expander 22 is provided between the discharge heat exchanger and the energy storage reservoir 1. In this way, the expansion of the energy storage medium is further utilized to generate electricity. The number and setting of the expanders can be set according to specific needs.

[0060] Among them, the power storage system also includes a first pressure energy collection device 23 and a second pressure energy collection device 24; the third heat exchanger 18 includes an outflow port for the outflow of the energy storage medium, and the outlet and outflow port of the third power storage heat exchange pipeline are both connected to the inlet of the first pressure energy collection device 23 through the pipeline; the second pressure energy collection device 24 is arranged between the outlet of the second power storage heat exchange pipeline and the inlet of the second throttle valve 13. The arrangement of the first pressure energy collection device 23 and the second pressure energy collection device 24 collects the pressure energy of the liquid energy storage medium in the system, and the collected pressure energy can be applied according to actual needs. The first pressure energy collection device 23 and the second pressure energy collection device 24 can be, but are not limited to, turbines.

[0061] In some optional embodiments, the power storage system also includes a heat exchange structure 25 for causing heat exchange between the first phase change device 4 and the second phase change device 7. The heat exchange structure 25 can absorb the heat released by the first phase change device 4 and can use the absorbed heat to heat the second phase change device 7. The heat exchange structure 25, the first phase change device 4 and the second phase change device 7 are integrated into a phase change cold storage heat exchanger with an integrated structure. It can be seen that the setting of the heat exchange structure 25 realizes the heat exchange between the first phase change device 4 and the second phase change device 7, avoids energy waste and improves energy utilization. The heat exchange structure 25, the first phase change device 4 and the second phase change device 7 are integrated into a phase change cold storage heat exchanger with an integrated structure, which is easy to install and improves installation efficiency.

[0062] The working principle of the power storage system is as follows.

[0063] Electricity storage stage: The energy storage reservoir 1 is initially in a state where the liquid energy storage medium is the main energy storage medium, and the gaseous energy storage medium is output. At this time, the liquid energy storage medium in the energy storage reservoir 1 is dynamically phase-changed into gaseous and solid states. The output gaseous energy storage medium releases cold energy through the electricity storage heat exchanger 14, is then compressed to the second pressure through the first compressor 2, and then is compressed through the first heat exchanger 3 to recover the compression heat, and then the first energy storage medium is separated, and the remaining energy storage medium is condensed and liquefied through the first phase change device 4, and then the second energy storage medium is separated, and the remaining energy storage medium is input into the first pressure After the energy collection device 23 reduces the pressure, it returns to the energy storage reservoir 1 through the first throttle valve 5. The first energy storage medium is compressed to a third pressure by the second compressor 11, condensed and liquefied by the condenser 12, and then cooled by the electric storage heat exchanger 14. Then, after the second pressure energy collection device 24 reduces the pressure, it returns to the energy storage reservoir 1 through the second throttle valve 13. The second energy storage medium is cooled by the electric storage heat exchanger 14 and then input into the first pressure energy collection device 23. In this cycle, the proportion of solid energy storage medium in the energy storage reservoir 1 is continuously increased, realizing the conversion of electrical energy into low-temperature cold energy.

[0064] Discharge process:

[0065] The energy storage reservoir 1 is initially in a state where solid energy storage medium is the main component, and outputs liquid energy storage medium, which is boosted to the fourth pressure by the power device 6 (such as a booster pump), and then one stream is diverted to enter the discharge heat exchanger 15 to release cold energy, and the rest enters the fourth heat exchanger 19 to release cold energy, and then the two streams merge and enter the second phase change device 7 for gasification, absorb heat by the second heat exchanger 8, and then generate electricity and reduce the pressure to the fifth pressure by the first expander 9, and then cool down by the cooler 10, and then further cool down by the discharge heat exchanger 15, and then generate electricity and reduce the pressure to the sixth pressure by the second expander 22, and then return to the energy storage reservoir 1, and heat exchange with the solid energy storage medium in the energy storage reservoir 1 and phase change to liquid together; in this cycle, the proportion of solid energy storage medium in the energy storage reservoir 1 is continuously reduced, and the low-temperature cold energy is converted into electrical energy. It should be noted that the fourth pressure is lower than the second pressure, and the sixth pressure is higher than the first pressure.

[0066] It can be seen from the above technical solutions that the energy storage system provided by the present application can directly store cold by phase change by selecting a suitable energy storage medium (such as ammonia) as a low-temperature phase change cold storage material, making the process flow of the energy storage process and the discharge process very simple, and simplifying the system equipment, which is conducive to improving energy storage efficiency and reducing investment.

[0067] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0068] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0069] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0070] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0071] It should be understood that the qualifiers "first", "second", "third", "fourth", "fifth" and "sixth" used in the description of the embodiments of the present application are only used to more clearly explain the technical solutions and cannot be used to limit the scope of protection of the present application.

[0072] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A power storage system, characterized in that: include: An electric storage circuit comprises an energy storage reservoir (1), a first compressor (2), a first heat exchanger (3), a first phase change device (4) for changing the phase of an energy storage medium from a gaseous state to a liquid state, a first throttle valve (5) and the energy storage reservoir (1) which are connected in series in sequence, so that the gaseous energy storage medium released by the energy storage reservoir (1) returns to the energy storage reservoir (1) after being compressed, cooled, liquefied and throttled, thereby causing the liquid energy storage medium in the energy storage reservoir (1) to change phase into a solid energy storage medium, thereby realizing the conversion of electric energy into cold energy; a first electricity storage shunt pipeline, wherein a second compressor (11), a condenser (12), and a second throttle valve (13) are sequentially connected in series on the first electricity storage shunt pipeline, an inlet of the second compressor (11) is connected to an outlet of the first heat exchanger (3), and an outlet of the second throttle valve (13) is connected to the energy storage reservoir (1); An electric storage heat exchanger (14), the electric storage heat exchanger (14) comprising: a first electric storage heat exchange pipeline, used to connect the energy storage reservoir (1) and the first compressor (2); a second electric storage heat exchange pipeline used to perform heat exchange with the first electric storage heat exchange pipeline, the second electric storage heat exchange pipeline being used to connect the condenser (12) and the second throttle valve (13); wherein the energy storage medium in the first electric storage heat exchange pipeline absorbs heat from the energy storage medium in the second electric storage heat exchange pipeline, so as to cool the energy storage medium entering the second throttle valve (13); A discharge circuit comprises the energy storage reservoir (1), a power device (6), a second phase change device (7) for changing the phase of the energy storage medium from a liquid state to a gaseous state, a second heat exchanger (8), a first expander (9), a cooler (10) and the energy storage reservoir (1) which are connected in series in sequence, so as to utilize the pressurization, gasification, overheating, expansion and cooling process of the liquid energy storage medium released by the energy storage reservoir (1) to generate electricity and then return to the energy storage reservoir (1), thereby causing the solid energy storage medium in the energy storage reservoir (1) to change phase into the liquid energy storage medium, so as to realize the conversion of cold energy into electrical energy; A discharge heat exchanger (15), comprising a second discharge heat exchange pipeline, wherein the second discharge heat exchange pipeline is used to connect the cooler (10) and the energy storage reservoir (1); The energy storage reservoir (1) is used to store energy storage media in a gas, liquid and solid coexisting state, and the energy storage media can undergo a transition between gas, liquid and solid states.

2. The power storage system according to claim 1, characterized in that: It also includes a discharge heat exchanger (15), wherein the discharge heat exchanger (15) includes: a first discharge heat exchange pipeline, used for connecting the power device (6) and the second phase change device (7); a second discharge heat exchange pipeline for performing heat exchange with the first discharge heat exchange pipeline, the second discharge heat exchange pipeline being used to connect the cooler (10) and the energy storage reservoir (1); The energy storage medium in the second discharge heat exchange pipeline releases heat to the energy storage medium in the first discharge heat exchange pipeline, so that the temperature of the energy storage medium entering the energy storage reservoir (1) is reduced.

3. The power storage system according to claim 1, characterized in that: Also includes a first cold tank (16) and a first hot tank (17); In the power storage stage, the first heat exchanger (3) absorbs the compression heat of the energy storage medium and transfers the compression heat to the heat exchange medium output from the first cold tank (16) to the first hot tank (17); in the discharge stage, the heat exchange medium is output from the first hot tank (17) to the first cold tank (16) and transfers the heat to the energy storage medium in the second heat exchanger (8).

4. The power storage system according to claim 1, characterized in that: Also includes: a third heat exchanger (18) disposed between the first phase change device (4) and the first throttle valve (5); A fourth heat exchanger (19) disposed between the power device (6) and the second phase change device (7); A second cold tank (20) and a second hot tank (21); In the power storage stage, the third heat exchanger (18) cools the energy storage medium and transfers the cold energy in the heat exchange medium output from the second cold tank (20) to the second hot tank (21) to the energy storage medium; in the discharge stage, the heat exchange medium is output from the second hot tank (21) to the second cold tank (20) and absorbs the cold energy of the energy storage medium through the fourth heat exchanger (19).

5. The power storage system according to claim 4, characterized in that: It also includes a second electricity storage shunt pipeline, the inlet of the second electricity storage shunt pipeline is connected to the outlet of the first phase change device (4), and the electricity storage heat exchanger (14) also includes a third electricity storage heat exchange pipeline for performing heat exchange with the first electricity storage heat exchange pipeline; The second electricity storage shunt pipeline is connected in series with the third electricity storage heat exchange pipeline, and the third electricity storage heat exchange pipeline is connected in parallel with the third heat exchanger (18) to adjust the heat exchange balance.

6. The power storage system according to claim 2, characterized in that: The discharge circuit comprises an inlet and an outlet connected to the energy storage reservoir (1), wherein the inlet is located below the liquid surface of the liquid energy storage medium so that the gaseous energy storage medium and the liquid energy storage medium are fully mixed; and / or, The power storage circuit comprises an air outlet and a liquid inlet which are connected to the energy storage reservoir (1), the air outlet being arranged at the top of the energy storage reservoir (1), and the liquid inlet being arranged above the liquid surface formed by the energy storage medium; And / or, a second expander (22) is provided between the discharge heat exchanger (15) and the energy storage reservoir (1).

7. The power storage system according to claim 5, characterized in that: It also includes a first pressure energy collection device (23) and a second pressure energy collection device (24); The third heat exchanger (18) comprises an outflow port for the energy storage medium to flow out, and the outlet of the third electricity storage and heat exchange pipeline and the outflow port are both connected to the inlet of the first pressure energy collection device (23) through a pipeline; The second pressure energy collection device (24) is arranged between the outlet of the second electricity storage and heat exchange pipeline and the inlet of the second throttle valve (13).

8. The power storage system according to claim 1, characterized in that: It also includes a heat exchange structure (25) for causing the first phase change device (4) and the second phase change device (7) to exchange heat, the heat exchange structure (25) being capable of absorbing heat released by the first phase change device (4) and being capable of using the absorbed heat to heat the second phase change device (7), the heat exchange structure (25), the first phase change device (4) and the second phase change device (7) being integrated into a phase change cold storage heat exchanger with an integrated structure.

Images