Reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electric complementary device

Abstract

The present invention discloses a reversible solid oxide battery and compressed air energy storage thermally coupled hydrogen-electricity complementary device, including: a reversible solid oxide battery and a compressed air energy storage system; the reversible solid oxide battery is connected to the compressed air energy storage system; the reversible solid oxide battery is used for electrolysis to produce hydrogen or generate electricity; the compressed air energy storage system is used to compress air with electric energy or release compressed air to drive a steam turbine to generate electricity. The present invention can achieve the synergistic improvement of thermal coupling and efficiency in the process of electricity and hydrogen storage, and the synergistic improvement of thermal coupling and efficiency in the process of discharge and power generation; it realizes the bidirectional thermal coupling of the reversible solid oxide battery and the compressed air energy storage, and also realizes the high-efficiency mutual conversion of hydrogen and electricity, and also realizes the reduction and simplification of the thermal management components of the reversible solid oxide battery and the heat storage components of the compressed air energy storage system, achieving three goals at one stroke.

Description

Technical Field

[0001] The present invention belongs to the field of energy technology, and in particular relates to a reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device. Background Art

[0002] Most existing technologies combine compressed air energy storage with solid oxide fuel cells (SOFC), proton exchange membrane fuel cells (PEMFC), lithium batteries, methanol hydrogen production devices, etc., through waste heat, waste pressure, flue gas combustibles, etc. The existing technologies have the following problems: they fail to achieve two-way waste heat exchange coupling; the heat released during the compression process of compressed air energy storage also needs to be stored separately for the heat absorption during the expansion process; the equipment components are complex, and the heat utilization is insufficient. Summary of the invention

[0003] In view of the above problems, the present invention discloses a reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device, comprising: a reversible solid oxide battery and a compressed air energy storage system;

[0004] The reversible solid oxide battery is connected to a compressed air energy storage system;

[0005] The reversible solid oxide battery is used for producing hydrogen or generating electricity by electrolysis;

[0006] The compressed air energy storage system is used to utilize electrical energy to compress air or release compressed air to drive a steam turbine to generate electricity.

[0007] Furthermore, the compressed air energy storage system comprises: a motor, a compressor unit, a first heat exchanger unit, an air storage device, a second heat exchanger unit, an expander unit and a generator;

[0008] The electric motor is connected to the compressor unit;

[0009] The compressor unit is connected to the first heat exchanger unit;

[0010] The first heat exchanger unit is connected to the gas inlet of the gas storage device;

[0011] The gas outlet of the gas storage device is connected to the second heat exchanger unit;

[0012] The second heat exchanger unit is connected to the expander unit;

[0013] The expander unit is connected to a generator.

[0014] Furthermore, the compressor unit includes a first compressor and a second compressor;

[0015] The first compressor and the second compressor are connected to the electric motor via the same transmission shaft.

[0016] Furthermore, the first heat exchanger unit includes a first heat exchanger and a second heat exchanger;

[0017] The gas inlet of the first heat exchanger is connected to the gas outlet of the first compressor via a pipeline, and the gas outlet is connected to the gas inlet of the second compressor;

[0018] The gas inlet of the second heat exchanger is connected to the gas outlet of the second compressor via a pipeline, and the gas outlet is connected to the inlet of the gas storage device via a pipeline;

[0019] The first heat exchanger and the second heat exchanger are respectively connected to the reversible solid oxide battery through pipelines.

[0020] Furthermore, the expander unit includes a first expander and a second expander;

[0021] The first expander and the second expander are connected to the generator via the same transmission shaft.

[0022] Furthermore, the second heat exchanger unit includes a third heat exchanger and a fourth heat exchanger;

[0023] The gas inlet of the third heat exchanger is connected to the outlet of the gas storage device through a pipeline, and the gas outlet is connected to the gas inlet of the first expander through a pipeline;

[0024] The gas inlet of the fourth heat exchanger is connected to the gas outlet of the first expander through a pipeline, and the gas outlet is connected to the gas inlet of the second expander through a pipeline;

[0025] The third heat exchanger and the fourth heat exchanger are respectively connected to the reversible solid oxide battery through pipelines.

[0026] Furthermore, the temperature of the gas compressed by the first compressor and the second compressor is 300-600°C.

[0027] Furthermore, the power of the reversible solid oxide battery is 10-1000kW.

[0028] Furthermore, the operating temperature of the reversible solid oxide battery is 600-1000°C.

[0029] Furthermore, the waste heat temperature of the reversible solid oxide battery in power generation mode is 500-600°C.

[0030] Compared with the prior art, the embodiments of the present invention have at least the following advantages: it can achieve the synergistic improvement of thermal coupling and efficiency in the electricity storage and hydrogen storage processes, and can also achieve the synergistic improvement of thermal coupling and efficiency in the discharge and power generation processes; it realizes the bidirectional thermal coupling of reversible solid oxide batteries (RSOC) and compressed air energy storage, and also realizes the high-efficiency hydrogen-electricity conversion, and also realizes the reduction and simplification of the thermal management components of the reversible solid oxide batteries (RSOC) and the heat storage components of the compressed air energy storage system, achieving three goals at one stroke.

[0031] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic structural diagram of a reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to an embodiment of the present invention is shown.

[0034] Figure numerals: 1. reversible solid oxide cell; 2. electric motor; 3. first compressor; 4. second compressor; 5. first heat exchanger; 6. second heat exchanger; 7. gas storage device; 8. third heat exchanger; 9. fourth heat exchanger; 10. first expander; 11. second expander; 12. generator. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In the electrolysis hydrogen production mode, the reversible solid oxide cell 1 (RSOC) becomes a solid oxide electrolyzer (SOEC), which requires a large amount of external heat to start and operate; in the hydrogen consumption power generation mode, it becomes a solid oxide fuel cell (SOFC), which releases a large amount of high-temperature waste heat and generates waste. In actual applications, the two opposite modes appear at different times over a long distance, and there is an obvious problem of energy waste. Heat storage can only reduce waste to a certain extent, and the temperature and heat of the heat storage device are difficult to fully meet the requirements of the two modes.

[0037] The compressed air energy storage system generates a large amount of compression heat during the compression and storage process; and needs to absorb a large amount of external heat during the expansion and discharge process. In practical applications, the compression and storage process and the expansion and discharge process also occur in different time periods with a long time interval. The heat storage device also has the problem of system energy waste due to problems such as heat transfer efficiency, heat storage temperature, and heat dissipation loss.

[0038] Figure 1 The schematic diagram of the structure of the reversible solid oxide battery and the compressed air energy storage thermal coupling hydrogen-electricity complementary device according to an embodiment of the present invention is shown. Figure 1 As shown, a reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device proposed by the present invention comprises: a reversible solid oxide battery 1 and a compressed air energy storage system;

[0039] The reversible solid oxide battery 1 is connected to a compressed air energy storage system;

[0040] The reversible solid oxide battery 1 is used for producing hydrogen or generating electricity by electrolysis;

[0041] The compressed air energy storage system is used to utilize electrical energy to compress air or release compressed air to drive a steam turbine to generate electricity.

[0042] The reversible solid oxide battery 1 of the present invention is thermally coupled to a compressed air energy storage system. The hydrogen-electricity complementary device can fully utilize the compression heat of the power consumption and power storage process of the compressor unit of the compressed air energy storage system when there is excess electric energy that needs to be converted and stored, and provide heat for the reversible solid oxide battery 1 (RSOC) in the electrolysis hydrogen production mode, thereby synergistically improving the thermal coupling and efficiency of the power storage and hydrogen storage processes. It can also fully utilize the waste heat of the reversible solid oxide battery 1 (RSOC) in the power generation mode when power generation and discharge are required during peak power consumption, and provide heat for the work discharge process of the expander unit of the compressed air energy storage system, thereby synergistically improving the thermal coupling and efficiency of the discharge and power generation processes.

[0043] In some embodiments, the compressed air energy storage system includes: a motor 2, a compressor unit, a first heat exchanger unit, a gas storage device 7, a second heat exchanger unit, an expander unit and a generator 12;

[0044] The motor 2 is connected to the compressor unit;

[0045] The compressor unit is connected to the first heat exchanger unit;

[0046] The first heat exchanger unit is connected to the gas inlet of the gas storage device 7;

[0047] The gas outlet of the gas storage device 7 is connected to the second heat exchanger unit;

[0048] The second heat exchanger unit is connected to the expander unit;

[0049] The expander unit is connected to a generator 12 .

[0050] Motor 2, used to drive the compressor unit to compress air;

[0051] The gas storage device 7 is used to store compressed air; illustratively, the gas storage device 7 can be a gas storage tank.

[0052] In some embodiments, the compressor unit includes a first compressor 3 and a second compressor 4;

[0053] The first compressor 3 and the second compressor 4 are connected to the motor 2 via the same transmission shaft.

[0054] The first compressor 3 and the second compressor 4 are both used for compressing air.

[0055] In the compressed air energy storage system, the compression ratio of a single-stage compressor is limited, while the total compression ratio of a two-stage compressor is the product of the two-stage compression ratios. Therefore, it can reach higher pressures and temperatures, store more energy, and can also be better coupled with the temperature range of the reversible solid oxide battery 1.

[0056] In some embodiments, the first heat exchanger unit includes a first heat exchanger 5 and a second heat exchanger 6;

[0057] The gas inlet of the first heat exchanger 5 is connected to the gas outlet of the first compressor 3 through a pipeline, and the gas outlet is connected to the gas inlet of the second compressor 4;

[0058] The gas inlet of the second heat exchanger 6 is connected to the gas outlet of the second compressor 4 through a pipeline, and the gas outlet is connected to the inlet of the gas storage device 7 through a pipeline;

[0059] The first heat exchanger 5 and the second heat exchanger 6 are respectively connected to the reversible solid oxide battery 1 through pipelines ( Figure 1). Exemplarily, a coil is provided in the reversible solid oxide battery 1, and the coil is connected to the first heat exchanger 5 and the second heat exchanger 6 through a pipeline, thereby transferring the heat generated by the compressor unit to the reversible solid oxide battery 1, providing the required heat for the reversible solid oxide battery 1.

[0060] A first heat exchanger 5, for transferring heat generated when compressing air to the reversible solid oxide battery 1;

[0061] The second heat exchanger 6 is used to transfer the heat generated when compressing the air to the reversible solid oxide battery 1.

[0062] Two heat exchangers are provided in the compressed air energy storage system, which can better adjust the air temperature during the compression process so that the air temperature is controlled within the required range. The first heat exchanger 5 between the two stages can adjust the temperature of the air entering the next stage compressor to prevent the air temperature from being too high, which will cause the next stage compressor to have difficulty in compression, increase power consumption, and reduce efficiency.

[0063] In some embodiments, the expander unit includes a first expander 10 and a second expander 11;

[0064] The first expander 10 and the second expander 11 are connected to a generator 12 via the same transmission shaft.

[0065] The first expander 10 is used to drive the generator 12 to generate electricity under the impetus of high-pressure air;

[0066] The second expander 11 is used to drive the generator 12 to generate electricity under the impetus of high-pressure air.

[0067] In the compressed air energy storage system, the expansion ratio of the single-stage expander is limited, while the total expansion ratio of the two-stage expander is the product of the two-stage expansion ratios. Therefore, it can meet the expansion work requirements of air with higher pressure and temperature, fully release energy, and better couple with the temperature range of the reversible solid oxide battery 1.

[0068] In some embodiments, the second heat exchanger unit includes a third heat exchanger 8 and a fourth heat exchanger 9;

[0069] The gas inlet of the third heat exchanger 8 is connected to the outlet of the gas storage device 7 through a pipeline, and the gas outlet is connected to the gas inlet of the first expander 10 through a pipeline;

[0070] The gas inlet of the fourth heat exchanger 9 is connected to the gas outlet of the first expander 10 through a pipeline, and the gas outlet is connected to the gas inlet of the second expander 11 through a pipeline;

[0071] The third heat exchanger 8 and the fourth heat exchanger 9 are respectively connected to the reversible solid oxide battery 1 through pipelines ( Figure 1(not shown). Exemplarily, a coil is provided in the reversible solid oxide cell 1, and the coil is connected to the third heat exchanger 8 and the fourth heat exchanger 9 through a pipeline, so that the heat generated by the reversible solid oxide cell 1 during power generation is transferred to the third heat exchanger 8 and the fourth heat exchanger 9, thereby heating the compressed air.

[0072] The third heat exchanger 8 is used to heat the compressed air using the heat generated when the reversible solid oxide battery 1 generates electricity;

[0073] The fourth heat exchanger 9 is used to heat the compressed air using the heat generated when the reversible solid oxide battery 1 generates electricity.

[0074] In the compressed air energy storage system, the two heat exchangers can better adjust the air temperature during the expansion process so that the air temperature is controlled within the required range. The fourth heat exchanger 9 between the two stages can adjust the air temperature entering the next stage expander, replenish heat in time, and prevent the air temperature from being too low, causing the air expansion work capacity in the next stage expander to decrease, and the efficiency of the expander to decrease.

[0075] It realizes bidirectional thermal coupling between the reversible solid oxide battery 1 and the compressed air energy storage system, realizes efficient hydrogen-electricity conversion, and reduces and simplifies the thermal management components of the reversible solid oxide battery 1 and the heat storage components of the compressed air energy storage system, achieving three goals at one stroke.

[0076] In some embodiments, the temperature of the gas compressed by the first compressor 3 and the second compressor 4 is 300-600° C. Preferably, the temperature of the compressed gas is set to 600° C.

[0077] In some embodiments, the power of the reversible solid oxide battery 1 is 10-1000 kW.

[0078] In some embodiments, the operating temperature of the reversible solid oxide battery 1 is 600-1000°C.

[0079] In some embodiments, the waste heat temperature of the reversible solid oxide battery 1 in the power generation mode is 500-600° C. Preferably, the waste heat temperature in the power generation mode is controlled at 600° C.

[0080] The reversible solid oxide battery 1 and the compressed air energy storage system are bidirectionally thermally coupled, which can achieve a high degree of proximity in temperature, heat, etc. Since there is no heat transfer loss caused by a large temperature difference, and there is no heat dissipation loss over time due to heat storage, the energy efficiency of the above two systems and in two directions can be improved at the same time; the slow startup problem of RSOC itself due to the heating process is also optimized and improved in the present invention; through the thermal coupling of the two systems, the thermal management components of the reversible solid oxide battery 1 (RSOC) and the heat storage components of the compressed air energy storage system are reduced and simplified, and the overall complexity of the system is reduced.

[0081] In the present invention, the reversible solid oxide battery 1 (RSOC) and the compressed air energy storage system are connected to the pipeline of the thermal management of the reversible solid oxide battery 1 through the interstage and outlet heat exchangers of the compressor unit in the compressed air energy storage system and the interstage and outlet heat exchangers of the expander unit to achieve bidirectional thermal coupling. The operation of the hydrogen-electric complementary device includes two processes: (1) power consumption, gas storage, and hydrogen production, and (2) gas release, hydrogen consumption, and power generation, thereby realizing the charging and discharging of the hybrid energy storage system.

[0082] (1) Power consumption, gas storage, and hydrogen production process: When there is excess power, the power drives the motor 2 and then drives the multi-stage compressor to compress the air to form high-pressure air, which is stored in the gas storage device 7. The compression heat generated during the air compression process is taken away by the first heat exchanger 5 and the second heat exchanger 6 of the multi-stage compressor and transferred to the reversible solid oxide cell 1 (RSOC) in the hydrogen production mode by electrolysis.

[0083] The reversible solid oxide cell 1 (RSOC) is equivalent to a solid oxide electrolyzer (SOEC) in the electrolysis hydrogen production mode. It can utilize excess electrical energy and cooperate with the heat transferred by the first heat exchanger unit of the compressed air energy storage system to electrolyze high-temperature water vapor to produce hydrogen, which can be stored or utilized.

[0084] (2) Gas release, hydrogen consumption, and power generation process: During peak electricity consumption, the reversible solid oxide cell 1 (RSOC) operates in a hydrogen consumption power generation mode, which is equivalent to a solid oxide fuel cell (SOFC). Hydrogen is input into the reversible solid oxide cell 1 to generate electricity, while generating high-temperature waste heat. The heat is transported to the second heat exchanger unit of the multi-stage expander of the compressed air energy storage system in the gas release power generation mode.

[0085] The high-pressure air in the gas storage device 7 of the compressed air energy storage system is released to drive the multi-stage expander to do work, thereby driving the generator 12 to generate electricity. A second heat exchanger unit is provided at the inlet and between the stages of the multi-stage expander to receive the heat of the reversible solid oxide battery 1 in the power generation mode, meet the heat absorption demand during the air expansion process, and improve the work efficiency.

[0086] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device, characterized in that: include: Reversible solid oxide battery (1) and compressed air energy storage system; The reversible solid oxide battery (1) is connected to a compressed air energy storage system; The reversible solid oxide battery (1) is used for producing hydrogen or generating electricity by electrolysis; The compressed air energy storage system is used to utilize electrical energy to compress air or release compressed air to drive a steam turbine to generate electricity.

2. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 1 is characterized in that: The compressed air energy storage system comprises: an electric motor (2), a compressor unit, a first heat exchanger unit, an air storage device (7), a second heat exchanger unit, an expander unit and a generator (12); The electric motor (2) is connected to the compressor unit; The compressor unit is connected to the first heat exchanger unit; The first heat exchanger unit is connected to a gas inlet of a gas storage device (7); The gas outlet of the gas storage device (7) is connected to the second heat exchanger unit; The second heat exchanger unit is connected to the expander unit; The expander unit is connected to a generator (12).

3. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 2 is characterized in that: The compressor unit comprises a first compressor (3) and a second compressor (4); The first compressor (3) and the second compressor (4) are connected to the electric motor (2) via the same transmission shaft.

4. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 3 is characterized in that: The first heat exchanger unit comprises a first heat exchanger (5) and a second heat exchanger (6); The gas inlet of the first heat exchanger (5) is connected to the gas outlet of the first compressor (3) via a pipeline, and the gas outlet is connected to the gas inlet of the second compressor (4); The gas inlet of the second heat exchanger (6) is connected to the gas outlet of the second compressor (4) via a pipeline, and the gas outlet is connected to the inlet of the gas storage device (7) via a pipeline; The first heat exchanger (5) and the second heat exchanger (6) are respectively connected to the reversible solid oxide battery (1) through pipelines.

5. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 4 is characterized in that: The expander unit comprises a first expander (10) and a second expander (11); The first expander (10) and the second expander (11) are connected to a generator (12) via the same transmission shaft.

6. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 5, characterized in that: The second heat exchanger unit comprises a third heat exchanger (8) and a fourth heat exchanger (9); The gas inlet of the third heat exchanger (8) is connected to the outlet of the gas storage device (7) through a pipeline, and the gas outlet is connected to the gas inlet of the first expander (10) through a pipeline; The gas inlet of the fourth heat exchanger (9) is connected to the gas outlet of the first expander (10) through a pipeline, and the gas outlet is connected to the gas inlet of the second expander (11) through a pipeline; The third heat exchanger (8) and the fourth heat exchanger (9) are respectively connected to the reversible solid oxide battery (1) through pipelines.

7. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 3 or 6, characterized in that: The temperature of the gas compressed by the first compressor (3) and the second compressor (4) is 300-600°C.

8. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 1, characterized in that: The power of the reversible solid oxide battery (1) is 10-1000 kW.

9. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 1, characterized in that: The operating temperature of the reversible solid oxide battery (1) is 600-1000°C.

10. The reversible solid oxide battery and compressed air energy storage thermal coupling hydrogen-electricity complementary device according to claim 1, characterized in that: The waste heat temperature of the reversible solid oxide battery (1) in power generation mode is 500-600°C.

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