A geological battery energy storage system and its operation method

Abstract

The present invention discloses a geological battery energy storage system and an operation method. The system includes a medium-low temperature heat storage module, a high-temperature heat storage module, and a heat engine cycle module. During the heat storage process, low-grade waste heat can be "pumped" to medium temperature and stored in the medium-low temperature heat storage well, or a medium-low temperature heat source can be transported by a solar collector, an air source heat pump, etc. and stored in the medium-low temperature heat storage well. During the charging process, an electric power is used to drive a heat pump cycle to upgrade the heat source of the medium-low temperature heat storage module and store it in the high-temperature heat storage well. During the discharging process, a heat engine cycle is adopted to convert the stored high-grade thermal energy into electric energy. The present invention can make full use of various types of underground spaces to promote new energy consumption and improve the stability of the power grid, and at the same time has the advantages of concealment and safety.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage, and particularly relates to a geological battery energy storage system and an operation method thereof. Background Art

[0002] With the rapid development of new energy technologies, the installed capacity and utilization rate of renewable energy represented by wind power and photovoltaic power have increased significantly. However, the defects of volatility and reverse peak shaving are becoming more and more prominent, which has a significant impact on the stability and security of the power grid. Therefore, it is urgent to develop new energy storage technologies to ensure the security and stability of the power grid. Summary of the Invention

[0003] The purpose of the present invention is to provide a geological battery energy storage system and an operation method thereof, which can make full use of industrial waste heat, or new energy such as solar energy and wind energy, store electric energy in the form of heat energy, effectively solve the problem of new energy consumption, and ensure the stability and security of the power grid.

[0004] To achieve the above purpose, the present invention provides a geological battery energy storage system, which includes a medium-low temperature heat storage module, a high-temperature heat storage module, and a heat engine cycle module connected in sequence;

[0005] The medium-low temperature heat storage module includes a low-temperature waste heat source, heat exchanger I, compressor I, heat exchanger II, a medium-low temperature heat storage well, and a multi-heat source heat collection device connected in sequence. A throttle valve I is connected between heat exchanger I and heat exchanger II;

[0006] The medium-low temperature heat storage module is connected to the high-temperature heat storage module through the medium-low temperature heat storage well;

[0007] The high-temperature heat storage module includes heat exchanger III, compressor II, heat exchanger IV, and a high-temperature heat storage well connected in sequence. Among them, heat exchanger III is connected to the medium-low temperature heat storage well, and a throttle valve II is connected between heat exchanger III and heat exchanger IV;

[0008] The high-temperature heat storage module is connected to the heat engine cycle module through the high-temperature heat storage well;

[0009] The heat engine cycle module includes heat exchanger V, a turbine, heat exchanger VI, and a cold source connected in sequence. Among them, heat exchanger V is connected to the high-temperature heat storage well, and a working fluid pump is connected between heat exchanger V and heat exchanger VI.

[0010] As a further solution of the present invention: The outlet of the medium and low temperature heat storage source in the medium and low temperature heat storage module is connected to the high temperature side inlet of Heat Exchanger I through Pump I, and the high temperature side outlet of Heat Exchanger I is connected to the low temperature heat source inlet; the low temperature side outlet of Heat Exchanger I is connected to the inlet of Compressor I, the outlet of Compressor I is connected to the high temperature side inlet of Heat Exchanger II, the high temperature side outlet of Heat Exchanger II is connected to the high pressure side of Throttle Valve I, and the low pressure side of Throttle Valve I is connected to the low temperature side inlet of Heat Exchanger I; the low temperature side outlet of Heat Exchanger II is connected to the medium and low temperature inlet of the medium and low temperature heat storage well, and the medium and low temperature outlet of the medium and low temperature heat storage well is connected to the low temperature side inlet of Heat Exchanger II through Pump II; the outlet of the multi-source heat collection device is connected to the medium and low temperature inlet of the medium and low temperature heat storage well, and the medium and low temperature outlet of the medium and low temperature heat storage well is connected to the inlet of the multi-source heat collection device.

[0011] As a further solution of the present invention: The high temperature side inlet of Heat Exchanger III in the high temperature heat storage module is connected to the high temperature outlet of the medium and low temperature heat storage well through Pump III, and the high temperature side outlet of Heat Exchanger III is connected to the high temperature inlet of the medium and low temperature heat storage well; the low temperature side outlet of Heat Exchanger III is connected to the inlet of Compressor II, the outlet of Compressor II is connected to the high temperature side inlet of Heat Exchanger IV, and the high temperature side outlet of Heat Exchanger IV is connected to the low temperature side inlet of Heat Exchanger III through Throttle Valve II; the low temperature side outlet of Heat Exchanger IV is connected to the high temperature port of the high temperature heat storage well, and the low temperature port of the high temperature heat storage well is connected to the low temperature side inlet of Heat Exchanger IV through Pump IV.

[0012] As a further solution of the present invention: The high temperature side inlet of Heat Exchanger V in the heat engine cycle module is connected to the high temperature port of the high temperature heat storage well through Pump V, and the high temperature side outlet of Heat Exchanger V is connected to the low temperature port of the high temperature heat storage well; the low temperature side outlet of Heat Exchanger V is connected to the turbine, the outlet of the turbine is connected to the high temperature side inlet of Heat Exchanger VI, and the high temperature side outlet of Heat Exchanger VI is connected to the low temperature side inlet of Heat Exchanger V through the working fluid pump; the low temperature side outlet of Heat Exchanger VI is connected to the cold source inlet, and the cold source outlet is connected to the low temperature side inlet of Heat Exchanger VI.

[0013] As a further solution of the present invention: The high temperature heat storage well includes a high temperature heat storage tank body entirely located below the ground. A flow equalizing distributor is provided inside the high temperature heat storage tank body, and the flow equalizing distributor is filled with a high temperature heat storage medium. The high temperature port is provided at the top of the high temperature heat storage tank body and above the ground, and the low temperature port is located on the lower side of the high temperature heat storage tank body. The low temperature port is led to the ground through a pipeline.

[0014] As a further solution of the present invention: The high temperature heat storage medium is a heat storage material spherical shell with a heat storage material sealed inside.

[0015] As a further solution of the present invention: The outside of the high temperature heat storage tank body is entirely surrounded by a heat insulation layer.

[0016] To achieve the above object, the present invention also provides an operation method for a geological battery energy storage system, including:

[0017] Medium and low temperature heat storage process: During operation, the medium and low temperature heat storage module is run, and the heat collected by the multi-source heat collection device is transferred to the medium and low temperature heat storage well for storage through water as the medium; when there is no high-temperature waste heat source or solar energy at the location and the multi-source heat collection device cannot provide suitable heat, the standby module is enabled: water absorbs heat in the low-temperature waste heat source and then enters the high-temperature side of Heat Exchanger I to release heat. The compressor I is driven by the redundant power of the power grid to compress the working fluid at the outlet of the low-temperature side of Heat Exchanger I into a high-temperature and high-pressure state. The high-temperature and high-pressure working fluid enters the high-temperature side of Heat Exchanger II to transfer heat to the water on the low-temperature side. The water that absorbs heat flows to the medium and low temperature heat storage well, and the heat is stored in the low-cost medium water in the form of sensible heat. The working fluid after releasing heat returns to Heat Exchanger I through Throttle Valve I to continue the cycle, realizing the temperature increase and storage of the heat in the low-temperature waste heat source;

[0018] During the high temperature heat storage process, the high temperature heat storage module is run. The heat in the medium and low temperature heat storage well is carried into the high temperature side of Heat Exchanger III through water. The compressor II is driven by the redundant power of the power grid to compress the working fluid at the outlet of the low temperature side of Heat Exchanger III into a high temperature and high pressure state. The high temperature and high pressure working fluid enters the high temperature side of Heat Exchanger IV to transfer heat to the pressurized water circulation working fluid. The pressurized water after absorbing heat releases the heat to the high temperature heat storage well through the heat exchanger or heat exchange tube for storage. The working fluid that releases heat in Heat Exchanger IV expands through Throttle Valve II, and the low temperature and low pressure working fluid at the outlet of Throttle Valve II returns to Heat Exchanger III to continue absorbing heat from the medium and low temperature heat storage well to complete the cycle;

[0019] During the discharging process, the medium and low temperature heat storage module and the high temperature heat storage module are turned off, and the heat engine module is run. The heat in the high temperature heat storage well is carried by the pressurized water circulation working fluid to Heat Exchanger V. The low-boiling-point working fluid absorbs heat from Heat Exchanger V and then enters the turbine to do work and generate electricity, and then enters Heat Exchanger VI to be cooled by the cold source, and then returns to Heat Exchanger V through the working fluid pump to absorb heat to complete the cycle.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. It can make full use of industrial waste heat, or new energy such as solar energy and wind energy, store electrical energy in the form of heat energy, effectively solve the problem of new energy consumption, and ensure the stability and safety of the power grid.

[0022] 2. The heat engine cycle module plays a significant role in improving the stability and safety of the power grid. The high temperature heat storage well has a higher energy density, can effectively cope with short-term supply shocks, and increase the proportion of low-carbon electricity in the power grid.

[0023] 3. Make full use of underground space resources as heat storage containers for different temperature zones, effectively collect various dispersed low-grade heat sources and store them in medium and low-temperature energy wells. After enhancing efficiency and quality, conduct high-temperature storage and achieve long-term, large-scale, and efficient storage, solving the problem of large-scale new energy consumption and providing a stable, reliable, and continuous high-energy heat source supply for subsequent high-temperature heat storage cycles.

[0024] 4. The main part is located underground, with flexible construction, mainly built in areas rich in waste heat resources for easy heat collection; at the same time, the core facilities have advantages such as concealment and safety, greatly improving the energy security. Brief Description of the Drawings

[0025] Figure 1 It is a schematic structural diagram of the geological battery energy storage system of the present invention;

[0026] Figure 2 It is a schematic structural diagram of the high-temperature heat storage well of the present invention;

[0027] Figure 3 It is a schematic structural diagram of the high-temperature heat storage medium in the high-temperature heat storage well of the present invention.

[0028] In the figure: 1, low-temperature waste heat source; 2, Pump I; 3, Heat Exchanger I; 4, Compressor I; 5, Heat Exchanger II; 6, Throttle Valve I; 7, medium and low-temperature heat storage well; 8, Pump II; 9, multi-source heat collection device; 10, Pump III; 11, Heat Exchanger III; 12, Compressor II; 13, Heat Exchanger IV; 14, Throttle Valve II; 15, high-temperature heat storage well; 16, Pump IV; 17, Pump V; 18, Heat Exchanger V; 19, Turbine; 20, Heat Exchanger VI; 21, working fluid pump; 22, cold source;

[0029] 151, high-temperature port; 152, high-temperature heat storage tank body; 153, heat insulation layer; 154, flow equalizing distributor; 155, low-temperature port; 156, high-temperature heat storage medium;

[0030] 1561, heat storage material spherical shell; 1562, heat storage material. Detailed Embodiment

[0031] The present invention will be further described below through embodiments.

[0032] As Figure 1 shown, a geological battery energy storage system includes a medium and low-temperature heat storage module, a high-temperature heat storage module, and a heat engine cycle module connected in sequence;

[0033] The medium and low-temperature heat storage module includes a low-temperature waste heat source 1, a Heat Exchanger I 3, a Compressor I 4, a Heat Exchanger II 5, a medium and low-temperature heat storage well 7, and a multi-source heat collection device 9 connected in sequence. A Throttle Valve I 6 is connected between the Heat Exchanger I 3 and the Heat Exchanger II 5;

[0034] The medium and low temperature heat storage module is connected to the high temperature heat storage module through the medium and low temperature heat storage well 7;

[0035] The high temperature heat storage module includes a heat exchanger III 11, a compressor II 12, a heat exchanger IV 13, and a high temperature heat storage well 15 connected in sequence. Among them, the heat exchanger III 11 is connected to the medium and low temperature heat storage well 7, and a throttle valve II 14 is connected between the heat exchanger III 11 and the heat exchanger IV 13;

[0036] The high temperature heat storage module is connected to the heat engine cycle module through the high temperature heat storage well 15;

[0037] The heat engine cycle module includes a heat exchanger V 18, a turbine 19, a heat exchanger VI 20, and a cold source 22 connected in sequence. Among them, the heat exchanger V 18 is connected to the high temperature heat storage well 15, and a working fluid pump 21 is connected between the heat exchanger V 18 and the heat exchanger VI 20.

[0038] Furthermore, the outlet of the medium and low temperature waste heat source 1 in the medium and low temperature heat storage module is connected to the high temperature side inlet of the heat exchanger I 3 through the pump I 2, and the high temperature side outlet of the heat exchanger I 3 is connected to the inlet of the low temperature waste heat source 1; the low temperature side outlet of the heat exchanger I 3 is connected to the inlet of the compressor I 4, the outlet of the compressor I 4 is connected to the high temperature side inlet of the heat exchanger II 5, the high temperature side outlet of the heat exchanger II 5 is connected to the high pressure side of the throttle valve I 6, and the low pressure side of the throttle valve I 6 is connected to the low temperature side inlet of the heat exchanger I 3; the low temperature side outlet of the heat exchanger II 5 is connected to the medium and low temperature inlet of the medium and low temperature heat storage well 7, and the medium and low temperature outlet of the medium and low temperature heat storage well 7 is connected to the low temperature side inlet of the heat exchanger II 5 through the pump II 8; the outlet of the multi-source heat collection device 9 is connected to the medium and low temperature inlet of the medium and low temperature heat storage well 7, and the medium and low temperature outlet of the medium and low temperature heat storage well 7 is connected to the inlet of the multi-source heat collection device 9.

[0039] The multi-source heat collection device 9 uses relatively high temperature industrial waste heat, solar energy, etc. as heat sources; the low temperature waste heat source 1, pump I 2, heat exchanger I 3, compressor I 4, heat exchanger II 5, throttle valve I 6, medium and low temperature heat storage well 7, and pump II 8 form a standby module, which is enabled as an alternative when the waste heat source temperature is relatively low.

[0040] The low temperature heat storage medium used in the low temperature heat storage well is a low-cost medium such as water; the stored heat can be directly used for scenarios with not high heat source temperature such as clean heating.

[0041] Furthermore, as Figure 1 and Figure 2As shown in the figure, the high-temperature inlet of the high-temperature side of heat exchanger III 11 in the high-temperature heat storage module is connected to the high-temperature outlet of the medium-low temperature heat storage well 7 through pump III 10, and the high-temperature outlet of heat exchanger III 11 is connected to the high-temperature inlet of the medium-low temperature heat storage well 7; the low-temperature outlet of heat exchanger III 11 is connected to the inlet of compressor II 12, the outlet of compressor II 12 is connected to the high-temperature inlet of heat exchanger IV 13, and the high-temperature outlet of heat exchanger IV 13 is connected to the low-temperature inlet of heat exchanger III 11 through throttle valve II 14; the low-temperature outlet of heat exchanger IV 13 is connected to the high-temperature port 151 of the high-temperature heat storage well 15, and the low-temperature port 155 of the high-temperature heat storage well 15 is connected to the low-temperature inlet of heat exchanger IV 13 through pump IV 16.

[0042] Furthermore, in the heat engine cycle module, the high-temperature inlet of heat exchanger V 18 is connected to the high-temperature port 151 of the high-temperature heat storage well 15 through pump V 17, and the high-temperature outlet of heat exchanger V 18 is connected to the low-temperature port 155 of the high-temperature heat storage well 15; the low-temperature outlet of heat exchanger V 18 is connected to turbine 19, the outlet of turbine 19 is connected to the high-temperature inlet of heat exchanger VI 20, and the high-temperature outlet of heat exchanger VI 20 is connected to the low-temperature inlet of heat exchanger V 18 through working fluid pump 21; the low-temperature outlet of heat exchanger VI 20 is connected to the inlet of cold source 22, and the outlet of cold source 22 is connected to the low-temperature inlet of heat exchanger VI 20.

[0043] Furthermore, the high-temperature heat storage well 15 includes a high-temperature heat storage tank body 152 entirely located below the ground. An even flow distributor 154 is provided inside the high-temperature heat storage tank body 152. The inside of the even flow distributor 154 is filled with a high-temperature heat storage medium 156. The high-temperature port 151 is provided at the top of the high-temperature heat storage tank body 152 and above the ground. The low-temperature port 155 is located on the lower side of the high-temperature heat storage tank body 152. For easy implementation in engineering, an inclined hole needs to be drilled in the surrounding rock on the side of the low-temperature port 155, and the low-temperature port 155 is led to the ground through a pipeline.

[0044] The medium that has absorbed heat in heat exchanger IV 13 flows into the high-temperature heat storage tank body 152 through the high-temperature port 151 of the high-temperature heat storage well 15, and after passing through the even flow distributor 154, it evenly flows to the area where the heat storage material spherical shell 1561 is located for heat release. The heat storage material spherical shell 1561 absorbs heat and begins to heat up; the medium after heat release flows out of the high-temperature heat storage tank body 152 through the low-temperature port 155 of the high-temperature heat storage well 15 and flows back to heat exchanger IV 13 through pump IV 16 to continue absorbing heat to complete the cycle.

[0045] Furthermore, the high-temperature heat storage medium 156 is a heat storage material spherical shell 1561 that internally seals a heat storage material 1562. The heat storage material 1562 is a phase change material such as crystalline hydrate salt, molten salt, paraffin, hydroxy acid, ester, polyol, or a thermochemical material such as metal hydride, oxide, peroxide, carbonate, sulfur trioxide, nitrate, halide salt.

[0046] As Figure 3As shown, the high-temperature heat storage medium 156 uses a phase change material. After the heat storage material spherical shell 1561 absorbs heat, its temperature rises, and the heat is stored in the heat storage material 1562 in the form of sensible heat. When the temperature rises to the melting point of the phase change material, the heat storage material 1562 begins to melt and its temperature rises, and the heat is stored in the form of latent heat and sensible heat.

[0047] Furthermore, in order to reduce the heat dissipation caused by the heat exchange between the high-temperature heat storage tank 152 and the environment, the high-temperature heat storage tank 152 is completely surrounded by a heat insulation layer 153.

[0048] An operation method of a geological battery energy storage system includes:

[0049] Medium and low-temperature heat storage process: During operation of the medium and low-temperature heat storage module, the heat collected by the multi-heat source heat collection device 9 is transferred to the medium and low-temperature heat storage well 7 for storage through water as a medium. When there is no high-temperature waste heat source or solar energy at the location and the multi-heat source heat collection device 9 cannot provide suitable heat, the standby module is enabled: Water absorbs heat in the low-temperature waste heat source 1 and then enters the high-temperature side of the heat exchanger I 3 to release heat. The redundant power of the power grid is used to drive the compressor I 4 to compress the working fluid at the outlet of the low-temperature side of the heat exchanger I 3 into a high-temperature and high-pressure state. The high-temperature and high-pressure working fluid enters the high-temperature side of the heat exchanger II 5 to transfer heat to the water on the low-temperature side. The water that absorbs heat flows to the medium and low-temperature heat storage well 7 to store the heat in the low-cost medium water in the form of sensible heat. The working fluid after releasing heat returns to the heat exchanger I 3 through the throttle valve I 6 to continue circulating, realizing the temperature rise and storage of the heat in the low-temperature waste heat source 1;

[0050] The heat pump unit can effectively collect the low-grade heat in the low-temperature waste heat source 1, but it requires additional power supply for the heat pump unit, and the additional power consumption will reduce the efficiency of the entire system. Therefore, it is used as a standby module and is only enabled under specific circumstances;

[0051] During the high-temperature heat storage process, the high-temperature heat storage module is operated. The heat in the medium and low-temperature heat storage well 7 is brought into the high-temperature side of the heat exchanger III 11 through water. The redundant power of the power grid is used to drive the compressor II 12 to compress the working fluid at the outlet of the low-temperature side of the heat exchanger III 11 into a high-temperature and high-pressure state. The high-temperature and high-pressure working fluid enters the high-temperature side of the heat exchanger IV 13 to transfer heat to the pressurized water circulation working fluid. The pressurized water after absorbing heat releases the heat to the high-temperature heat storage well 15 for storage through the heat exchanger or heat exchange tube. The working fluid that releases heat in the heat exchanger IV 13 expands through the throttle valve II 14, and the low-temperature and low-pressure working fluid at the outlet of the throttle valve II 14 returns to the heat exchanger III 11 to continue absorbing heat from the medium and low-temperature heat storage well 7 to complete the cycle;

[0052] Therefore, the high-temperature heat storage process is to use the redundant power to convert the low-grade thermal energy into high-grade thermal energy through the heat pump cycle and store it in the high-temperature heat storage well 15;

[0053] During the discharging process, the medium-temperature heat storage module and the high-temperature heat storage module are shut down, and the heat engine module operates. The heat in the high-temperature heat storage well 15 is carried by the pressurized water circulation working medium to the heat exchanger Ⅴ18. After absorbing heat from the heat exchanger Ⅴ18, the low-boiling-point working medium enters the turbine 19 to do work and generate electricity, then enters the heat exchanger Ⅵ20 to be cooled by the cold source 22, and then returns to the heat exchanger Ⅴ18 through the working medium pump 21 to absorb heat, completing the cycle.

[0054] Therefore, during the discharging process, the stored high-grade thermal energy is converted into electrical energy according to the grid demand.

Claims

1. A geological battery energy storage system, characterized in that, It includes a medium-low temperature heat storage module, a high temperature heat storage module, and a heat engine cycle module that are connected in sequence; The medium-low temperature heat storage module includes a low temperature waste heat source (1), a heat exchanger I (3), a compressor I (4), a heat exchanger II (5), a medium-low temperature heat storage well (7), and a multi-heat source heat collection device (9) that are connected in sequence. A throttle valve I (6) is connected between the heat exchanger I (3) and the heat exchanger II (5); The medium-low temperature heat storage module is connected to the high temperature heat storage module through the medium-low temperature heat storage well (7); The high temperature heat storage module includes a heat exchanger III (11), a compressor II (12), a heat exchanger IV (13), and a high temperature heat storage well (15) that are connected in sequence. Among them, the heat exchanger III (11) is connected to the medium-low temperature heat storage well (7), and a throttle valve II (14) is connected between the heat exchanger III (11) and the heat exchanger IV (13); The high temperature heat storage module is connected to the heat engine cycle module through the high temperature heat storage well (15); The heat engine cycle module includes a heat exchanger V (18), a turbine (19), a heat exchanger VI (20), and a cold source (22) that are connected in sequence. Among them, the heat exchanger V (18) is connected to the high temperature heat storage well (15), and a working fluid pump (21) is connected between the heat exchanger V (18) and the heat exchanger VI (20); In the high temperature heat storage module, the high temperature side inlet of the heat exchanger III (11) is connected to the high temperature outlet of the medium-low temperature heat storage well (7) through a pump III (10), and the high temperature side outlet of the heat exchanger III (11) is connected to the high temperature inlet of the medium-low temperature heat storage well (7); the low temperature side outlet of the heat exchanger III (11) is connected to the inlet of the compressor II (12), the outlet of the compressor II (12) is connected to the high temperature side inlet of the heat exchanger IV (13), and the high temperature side outlet of the heat exchanger IV (13) is connected to the low temperature side inlet of the heat exchanger III (11) through a throttle valve II (14); the low temperature side outlet of the heat exchanger IV (13) is connected to the high temperature port (151) of the high temperature heat storage well (15), and the low temperature port (155) of the high temperature heat storage well (15) is connected to the low temperature side inlet of the heat exchanger IV (13) through a pump IV (16).

2. The geological battery energy storage system according to claim 1, characterized in that, In the medium-low temperature heat storage module, the outlet of the low temperature waste heat source (1) is connected to the high temperature side inlet of the heat exchanger I (3) through a pump I (2), and the high temperature side outlet of the heat exchanger I (3) is connected to the inlet of the low temperature waste heat source (1); the low temperature side outlet of the heat exchanger I (3) is connected to the inlet of the compressor I (4), the outlet of the compressor I (4) is connected to the high temperature side inlet of the heat exchanger II (5), the high temperature side outlet of the heat exchanger II (5) is connected to the high pressure side of the throttle valve I (6), and the low pressure side of the throttle valve I (6) is connected to the low temperature side inlet of the heat exchanger I (3); the low temperature side outlet of the heat exchanger II (5) is connected to the medium-low temperature inlet of the medium-low temperature heat storage well (7), and the medium-low temperature outlet of the medium-low temperature heat storage well (7) is connected to the low temperature side inlet of the heat exchanger II (5) through a pump II (8); the outlet of the multi-heat source heat collection device (9) is connected to the medium-low temperature inlet of the medium-low temperature heat storage well (7), and the medium-low temperature outlet of the medium-low temperature heat storage well (7) is connected to the inlet of the multi-heat source heat collection device (9).

3. A geological battery energy storage system according to claim 1, characterized in that, In the heat engine cycle module, the high-temperature side inlet of heat exchanger V (18) is connected to the high-temperature port (151) of the high-temperature heat storage well (15) through pump V (17), and the high-temperature side outlet of heat exchanger V (18) is connected to the low-temperature port (155) of the high-temperature heat storage well (15); the low-temperature side outlet of heat exchanger V (18) is connected to turbine (19), the outlet of turbine (19) is connected to the high-temperature side inlet of heat exchanger VI (20), and the high-temperature side outlet of heat exchanger VI (20) is connected to the low-temperature side inlet of heat exchanger V (18) through working fluid pump (21); the low-temperature side outlet of heat exchanger VI (20) is connected to the inlet of cold source (22), and the outlet of cold source (22) is connected to the low-temperature side inlet of heat exchanger VI (20).

4. A geological battery energy storage system according to claim 1 or 3, characterized in that, The high-temperature heat storage well (15) includes a high-temperature heat storage tank body (152) entirely located below the ground. A flow equalizing distributor (154) is provided inside the high-temperature heat storage tank body (152), and the inside of the flow equalizing distributor (154) is filled with a high-temperature heat storage medium (156). The high-temperature port (151) is provided at the top of the high-temperature heat storage tank body (152) and above the ground, and the low-temperature port (155) is located on the lower side of the high-temperature heat storage tank body (152), and the low-temperature port (155) is led to the ground through a pipeline.

5. A geological battery energy storage system according to claim 4, characterized in that, The high-temperature heat storage medium (156) is a heat storage material spherical shell (1561) with a heat storage material (1562) sealed inside.

6. The geological battery energy storage system according to claim 4, characterized in that, The outside of the high-temperature heat storage tank body (152) is entirely surrounded by a heat insulation layer (153).

7. The operating method of a geological battery energy storage system according to claim 3, characterized in that Including: Medium and low-temperature heat storage process: During operation of the medium and low-temperature heat storage module, the heat collected by the multi-source heat collection device (9) is transferred to the medium and low-temperature heat storage well (7) for storage through water as a medium; when there is no high-temperature waste heat source or solar energy at the location and the multi-source heat collection device (9) cannot provide suitable heat, the standby module is enabled: Water absorbs heat in the low-temperature waste heat source (1) and then enters the high-temperature side of heat exchanger I (3) to release heat. The redundant power of the power grid is used to drive compressor I (4) to compress the working fluid at the outlet of the low-temperature side of heat exchanger I (3) into a high-temperature and high-pressure state. The high-temperature and high-pressure working fluid enters the high-temperature side of heat exchanger II (5) to transfer heat to the water on the low-temperature side. The water that absorbs heat flows to the medium and low-temperature heat storage well (7) to store the heat in the low-cost medium water in the form of sensible heat. The working fluid after releasing heat returns to heat exchanger I (3) through throttle valve I (6) to continue the cycle, realizing the temperature-raising storage of the heat in the low-temperature waste heat source (1). During the high-temperature heat storage process, the high-temperature heat storage module is operated. The heat in the medium and low-temperature heat storage well (7) is brought into the high-temperature side of heat exchanger III (11) through water. The redundant power of the power grid is used to drive compressor II (12) to compress the working fluid at the outlet of the low-temperature side of heat exchanger III (11) into a high-temperature and high-pressure state. The high-temperature and high-pressure working fluid enters the high-temperature side of heat exchanger IV (13) to transfer heat to the pressurized water circulation working fluid. The pressurized water after absorbing heat releases the heat to the high-temperature heat storage well (15) for storage through a heat exchanger or heat exchange tube. The working fluid that releases heat in heat exchanger IV (13) expands through throttle valve II (14). The low-temperature and low-pressure working fluid at the outlet of throttle valve II (14) returns to heat exchanger III (11) to continue absorbing heat from the medium and low-temperature heat storage well (7) to complete the cycle. During the shutdown of the discharging process, the low-temperature heat storage module and the high-temperature heat storage module are turned off, and the heat engine module is operated. The heat in the high-temperature heat storage well (15) is carried by the pressurized water circulation working medium to the heat exchanger V (18). After the low-boiling-point working medium absorbs heat from the heat exchanger V (18), it enters the turbine (19) to do work and generate electricity, then enters the heat exchanger VI (20) to be cooled by the cold source (22), and then returns to the heat exchanger V (18) through the working medium pump (21) to absorb heat, completing the cycle.

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