Geological battery energy storage system and operation method thereof

Abstract

The invention discloses a geological battery energy storage system and an operation method. The system comprises a medium and low temperature heat storage module, a high temperature heat storage module and a heat engine circulation module. In the heat storage process, low-grade waste heat can be pumped to the medium temperature to be stored in the medium-low temperature heat storage well, or a solar heat collector, an air source heat pump and the like are used for conveying medium-low temperature heat sources to be stored in the medium-temperature heat storage well. In the charging process, a heat source of the medium-low temperature heat storage module is upgraded and stored in a high-temperature heat storage well by using electric power to drive heat pump circulation; in the discharging process, heat engine circulation is adopted to convert stored high-grade heat energy into electric energy. According to the invention, multiple types of underground spaces can be fully utilized to promote new energy consumption, the stability of a power grid is improved, and meanwhile, concealment and safety are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage, and in particular 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, and the volatility and anti-peaking defects they face have become increasingly 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 its operation method, which 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 thermal energy, effectively solve the problem of new energy consumption, and ensure the stability and safety of the power grid.

[0004] To achieve the above-mentioned object, the present invention provides a geological battery energy storage system, comprising a medium-low temperature heat storage module, a high temperature heat storage module and a heat engine cycle module connected in sequence; The medium and low temperature heat storage module comprises a medium and low temperature heat storage well, a heat exchanger I, a compressor I, a heat exchanger II, a medium and low temperature heat storage well and a multi-heat source heat collection device which are connected in sequence, and a throttle valve I is connected between the heat exchanger I and the heat exchanger II; 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; The high-temperature heat storage module includes a heat exchanger III, a compressor II, a heat exchanger IV and a high-temperature heat storage well which are connected in sequence, wherein the heat exchanger III is connected to the medium- and low-temperature heat storage well, and a throttle valve II is connected between the heat exchanger III and the heat exchanger IV; The high temperature heat storage module is connected to the heat engine cycle module through a high temperature heat storage well; The heat engine cycle module comprises a heat exchanger V, a turbine, a heat exchanger VI and a cold source which are connected in sequence, wherein the heat exchanger V is connected to a high-temperature heat storage well, and a working fluid pump is connected between the heat exchanger V and the heat exchanger VI.

[0005] As a further solution of the present invention: the outlet of the medium and low temperature waste heat source of the medium and low temperature heat storage module is connected to the high temperature side inlet of the heat exchanger I through pump I, and the high temperature side outlet of the heat exchanger I is connected to the inlet of the low temperature waste heat source; the low temperature side outlet of the heat exchanger I is connected to the inlet of the compressor I, the outlet of the compressor I is connected to the high temperature side inlet of the heat exchanger II, the high temperature side outlet of the heat exchanger II is connected to the high pressure side of the throttle valve I, and the low pressure side of the throttle valve I is connected to the low temperature side inlet of the heat exchanger I; the low temperature side outlet of the 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 the heat exchanger II through pump II; the outlet of the multi-heat 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-heat source heat collection device.

[0006] 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.

[0007] As a further solution of the present invention: the high-temperature side inlet of the heat exchanger V in the heat engine circulation 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 the heat exchanger V is connected to the low-temperature port of the high-temperature heat storage well; the low-temperature side outlet of the heat exchanger V is connected to the turbine, the turbine outlet is connected to the high-temperature side inlet of the heat exchanger VI, and the high-temperature side outlet of the heat exchanger VI is connected to the low-temperature side inlet of the heat exchanger V through a working fluid pump; the low-temperature side outlet of the heat exchanger VI is connected to the inlet of the cold source, and the cold source outlet is connected to the low-temperature side inlet of the heat exchanger VI.

[0008] As a further solution of the present invention: the high-temperature heat storage well includes a high-temperature heat storage tank body which is located as a whole below the ground, a flow distributor is arranged inside the high-temperature heat storage tank body, a high-temperature heat storage medium is filled inside the flow distributor, a high-temperature port is arranged at the top of the high-temperature heat storage tank body and is located above the ground, a low-temperature port is located at the lower side of the high-temperature heat storage tank body, and the low-temperature port is led to the ground through a pipeline.

[0009] As a further solution of the present invention: the high-temperature heat storage medium is a heat storage material spherical shell with the heat storage material sealed inside.

[0010] As a further solution of the present invention: the high-temperature heat storage tank is completely surrounded by a heat-insulating layer.

[0011] To achieve the above object, the present invention also provides an operation method of a geological battery energy storage system, comprising: Medium and low temperature heat storage process: operate the medium and low temperature heat storage module, and the heat collected in the multi-heat source heat collection device is transferred to the medium and low temperature heat storage well through water as a medium for storage; when there is no waste heat source or solar energy with a higher temperature at the location, and the multi-heat source heat collection device cannot provide suitable heat, activate the backup module: water absorbs heat from the low temperature waste heat source and enters the high temperature side of heat exchanger I to release heat, and uses the excess power of the power grid to drive compressor I 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, and 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, and the water that absorbs heat flows to the medium and low temperature heat storage well, and stores the heat in the low cost medium water in the form of sensible heat, and the working fluid after releasing heat returns to heat exchanger I through throttle valve I to continue to circulate, so as to realize the heating storage of heat in the low temperature waste heat source; In the high-temperature heat storage process, the high-temperature heat storage module is operated, and the heat in the medium- and low-temperature heat storage wells is brought into the high-temperature side of the heat exchanger III through water. The excess power of the power grid is used to drive the compressor II to compress the working fluid at the outlet of the low-temperature side of the 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 the heat exchanger IV to transfer heat to the pressurized water circulating working fluid. The pressurized water after absorbing heat releases heat to the high-temperature heat storage well through the heat exchanger or heat exchange pipe for storage. The working fluid that releases heat in the heat exchanger IV expands through the throttle valve II. The low-temperature and low-pressure working fluid at the outlet of the throttle valve II returns to the heat exchanger III to continue to absorb heat from the medium- and low-temperature heat storage wells, completing the cycle. During the discharge process, the medium and low temperature heat storage module and the high temperature heat storage module are closed, and the heat engine module is operated. The heat in the high temperature heat storage well is carried to the heat exchanger V by the pressurized water circulating working fluid. The low boiling point working fluid absorbs heat from the heat exchanger V and enters the turbine to generate power, then enters the heat exchanger VI to be cooled by the cold source, and then returns to the heat exchanger V through the working fluid pump to absorb heat, completing the cycle.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 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 thermal energy, effectively solve the problem of new energy consumption, and ensure the stability and security of the power grid.

[0013] 2. The thermal 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, which can effectively respond to short-term supply shocks and increase the proportion of low-carbon electricity in the power grid.

[0014] 3. Make full use of underground space resources, use it as a heat storage container for non-temperature zones, effectively collect various dispersed low-grade heat sources and store them in medium and low temperature energy wells, store them at high temperatures after improving efficiency and quality, 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.

[0015] 4. The main part is located underground, and its construction is flexible. It is mainly built in areas with rich waste heat resources to facilitate heat collection. At the same time, the core facilities have the advantages of concealment and safety, which greatly improves the safety of energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the geological battery energy storage system of the present invention; Figure 2 This is a schematic diagram of the structure of the high-temperature heat storage well of the present invention; Figure 3 It is a schematic diagram of the structure of the high-temperature heat storage medium in the high-temperature heat storage well of the present invention.

[0017] 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-heat 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; 151, high temperature port, 152, high temperature heat storage tank, 153, insulation layer, 154, flow distributor, 155, low temperature port, 156, high temperature heat storage medium; 1561. Heat storage material spherical shell, 1562. Heat storage material. DETAILED DESCRIPTION

[0018] The present invention will be further described below by way of examples.

[0019] like Figure 1 As shown, a geological battery energy storage system includes a medium-low temperature heat storage module, a high temperature heat storage module and a heat engine cycle module connected in sequence; The medium and low temperature heat storage module comprises a medium and low temperature heat storage well 7, a heat exchanger I3, a compressor I4, a heat exchanger II5, a medium and low temperature heat storage well 7 and a multi-heat source heat collection device 9 which are connected in sequence, and a throttle valve I6 is connected between the heat exchanger I3 and the heat exchanger II5; 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; The high-temperature heat storage module includes a heat exchanger III11, a compressor II12, a heat exchanger IV13 and a high-temperature heat storage well 15 which are connected in sequence, wherein the heat exchanger III11 is connected to the medium- and low-temperature heat storage well 7, and a throttle valve II14 is connected between the heat exchanger III11 and the heat exchanger IV13; The high temperature heat storage module is connected to the heat engine cycle module via the high temperature heat storage well 15; The heat engine cycle module includes a heat exchanger V18, a turbine 19, a heat exchanger VI20, and a cold source 22 which are connected in sequence, wherein the heat exchanger V18 is connected to the high-temperature heat storage well 15, and a working fluid pump 21 is connected between the heat exchanger V18 and the heat exchanger VI20.

[0020] Furthermore, the outlet of the medium and low temperature waste heat source 1 of the medium and low temperature heat storage module is connected to the high temperature side inlet of the heat exchanger Ⅰ3 through pump Ⅰ2, and the high temperature side outlet of the heat exchanger Ⅰ3 is connected to the inlet of the low temperature waste heat source 1; the low temperature side outlet of the heat exchanger Ⅰ3 is connected to the inlet of the compressor Ⅰ4, the outlet of the compressor Ⅰ4 is connected to the high temperature side inlet of the heat exchanger Ⅱ5, the high temperature side outlet of the heat exchanger Ⅱ5 is connected to the high pressure side of the throttle valve Ⅰ6, and the low pressure side of the throttle valve Ⅰ6 is connected to the low temperature side inlet of the heat exchanger Ⅰ3; the low temperature side outlet of the heat exchanger Ⅱ5 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 Ⅱ5 through pump Ⅱ8; the outlet of the multi-heat 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-heat source heat collection device 9.

[0021] The multi-heat source heat collection device 9 uses relatively high-temperature industrial waste heat, solar energy, etc. as heat sources; low-temperature waste heat source 1, pump I2, heat exchanger I3, compressor I4, heat exchanger II5, throttle valve I6, medium and low temperature heat storage well 7, pump II8 form a backup module, which is activated as an alternative solution when the temperature of the waste heat source is low.

[0022] The low-temperature heat storage medium used in low-temperature heat storage wells is low-cost media such as water; the heat stored in it can be directly used in scenarios such as clean heating where the heat source temperature is not high.

[0023] Further, such as Figure 1 and Figure 2 As shown, the high-temperature side inlet of the heat exchanger III11 in the high-temperature heat storage module is connected to the high-temperature outlet of the medium- and low-temperature heat storage well 7 through the pump III10, and the high-temperature side outlet of the heat exchanger III11 is connected to the high-temperature inlet of the medium- and low-temperature heat storage well 7; the low-temperature side outlet of the heat exchanger III11 is connected to the inlet of the compressor II12, and the outlet of the compressor II12 is connected to the high-temperature side inlet of the heat exchanger IV13, and the high-temperature side outlet of the heat exchanger IV13 is connected to the low-temperature side inlet of the heat exchanger III11 through the throttle valve II14; the low-temperature side outlet of the heat exchanger IV13 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 IV13 through the pump IV16.

[0024] Furthermore, in the heat engine circulation module, the high-temperature side inlet of the heat exchanger V18 is connected to the high-temperature port 151 of the high-temperature heat storage well 15 through the pump V17, and the high-temperature side outlet of the heat exchanger V18 is connected to the low-temperature port 155 of the high-temperature heat storage well 15; the low-temperature side outlet of the heat exchanger V18 is connected to the turbine 19, and the outlet of the turbine 19 is connected to the high-temperature side inlet of the heat exchanger VI20, and the high-temperature side outlet of the heat exchanger VI20 is connected to the low-temperature side inlet of the heat exchanger V18 through the working fluid pump 21; the low-temperature side outlet of the heat exchanger VI20 is connected to the inlet of the cold source 22, and the outlet of the cold source 22 is connected to the low-temperature side inlet of the heat exchanger VI20.

[0025] Furthermore, the high-temperature heat storage well 15 includes a high-temperature heat storage tank body 152 which is located as a whole below the ground. A flow distributor 154 is provided inside the high-temperature heat storage tank body 152. The flow distributor 154 is filled with a high-temperature heat storage medium 156. A high-temperature port 151 is provided at the top of the high-temperature heat storage tank body 152 and is located above the ground. A low-temperature port 155 is located at the lower side of the high-temperature heat storage tank body 152. For ease of engineering implementation, 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.

[0026] The medium that has absorbed heat in the heat exchanger IV13 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 evenly flows to the area where the heat storage material spherical shell 1561 is located after passing through the uniform flow distributor 154 to release heat. The heat storage material spherical shell 1561 absorbs heat and begins to heat up; the medium that has released heat 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 the heat exchanger IV13 through the pump IV16 to continue absorbing heat to complete the cycle.

[0027] Furthermore, the high-temperature heat storage medium 156 is a heat storage material spherical shell 1561 that internally seals a heat storage material 1562, and the heat storage material 1562 is a phase change material such as a crystalline hydrated salt, a molten salt, a paraffin, a hydroxy acid, an ester, a polyol, or a thermochemical material such as a metal hydride, an oxide, a peroxide, a carbonate, sulfur trioxide, a nitrate, and a halide salt.

[0028] like Figure 3 As shown, the high-temperature heat storage medium 156 adopts phase change material. After the heat storage material shell 1561 absorbs heat, the 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 heat up, and the heat is stored in the form of latent heat and sensible heat.

[0029] Furthermore, in order to reduce the heat dissipation caused by the heat exchange between the high-temperature heat storage tank body 152 and the environment, the high-temperature heat storage tank body 152 is completely surrounded by a heat preservation layer 153.

[0030] A method for operating a geological battery energy storage system, comprising: Medium and low temperature heat storage process: the medium and low temperature heat storage module is operated, and the heat collected in the multi-heat source heat collection device 9 is transferred to the medium and low temperature heat storage well 7 through water as a medium for storage; when there is no waste heat source or solar energy with a higher temperature at the location, and the multi-heat source heat collection device 9 cannot provide suitable heat, the standby module is activated: the water absorbs heat in the low temperature waste heat source 1 and enters the high temperature side of the heat exchanger Ⅰ3 to release heat, and the excess power of the power grid is used to drive the compressor Ⅰ4 to compress the working fluid at the low temperature side outlet of the heat exchanger Ⅰ3 into a high temperature and high pressure state, and the high temperature and high pressure working fluid enters the high temperature side of the heat exchanger Ⅱ5 to transfer the heat to the low temperature side water, and the water that absorbs the heat flows to the medium and low temperature heat storage well 7, and stores the heat in the low cost medium water in the form of sensible heat, and the working fluid after releasing heat returns to the heat exchanger Ⅰ3 through the throttle valve Ⅰ6 to continue to circulate, so as to realize the heating storage of the heat in the low temperature waste heat source 1; The heat pump unit can effectively collect low-grade heat from the low-temperature waste heat source 1, but it needs additional power supply to the heat pump unit. The additional power consumption will reduce the efficiency of the whole system, so it is used as a backup module and is only enabled in specific circumstances. In the high-temperature heat storage process, the high-temperature heat storage module is operated, and the heat in the medium-low temperature heat storage well 7 is brought into the high-temperature side of the heat exchanger III11 through water. The excess power of the power grid is used to drive the compressor II12 to compress the working fluid at the outlet of the low-temperature side of the heat exchanger III11 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 IV13 to transfer heat to the pressurized water circulating working fluid. The pressurized water after absorbing heat releases heat to the high-temperature heat storage well 15 through the heat exchanger or heat exchange pipe for storage. The working fluid that releases heat in the heat exchanger IV13 expands through the throttle valve II14. The low-temperature and low-pressure working fluid at the outlet of the throttle valve II14 returns to the heat exchanger III11 to continue to absorb heat from the medium-low temperature heat storage well 7, completing the cycle. Therefore, the high-temperature heat storage process is to use excess electricity to convert low-grade heat energy into high-grade heat energy through a heat pump cycle and store it in a high-temperature heat storage well 15; During the discharge 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 operated. The heat in the high temperature heat storage well 15 is carried to the heat exchanger V18 by the pressurized water circulating working fluid. The low boiling point working fluid absorbs heat from the heat exchanger V18 and enters the turbine 19 to perform work and generate electricity, and 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 fluid pump 21 to absorb heat, completing the cycle.

[0031] Therefore, the discharge process converts the stored high-grade thermal energy into electrical energy according to the grid demand.

Claims

1. A geological battery energy storage system, characterized in that: It includes a medium and low temperature heat storage module, a high temperature heat storage module and a heat engine cycle module connected in sequence; The medium-low temperature heat storage module comprises a medium-low temperature heat storage well (7), 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) which are connected in sequence, and a throttle valve I (6) is connected between the heat exchanger I (3) and the heat exchanger II (5); The medium and low temperature heat storage module is connected to the high temperature heat storage module via the medium and low temperature heat storage well (7); The high-temperature heat storage module comprises a heat exchanger III (11), a compressor II (12), a heat exchanger IV (13) and a high-temperature heat storage well (15) which are connected in sequence, wherein 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); The high-temperature heat storage module is connected to the heat engine cycle module via a high-temperature heat storage well (15); The heat engine circulation module comprises a heat exchanger V (18), a turbine (19), a heat exchanger VI (20), and a cold source (22) which are connected in sequence, wherein the heat exchanger V (18) is connected to a 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).

2. A geological battery energy storage system according to claim 1, characterized in that: The outlet of the medium-low temperature waste heat source (1) of the medium-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), and the outlet of the compressor I (4) is connected to the high temperature side inlet of the heat exchanger II (5), and 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 the 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 2, characterized in that: The high-temperature side inlet of the 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 the 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), and 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 the 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 the pump IV (16).

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

5. A geological battery energy storage system according to claim 3 or 4, characterized in that: The high-temperature heat storage well (15) comprises a high-temperature heat storage tank body (152) which is entirely located below the ground. A flow equalizer (154) is provided in the high-temperature heat storage tank body (152). The flow equalizer (154) is filled with a high-temperature heat storage medium (156). A high-temperature port (151) is provided at the top of the high-temperature heat storage tank body (152) and is located above the ground. A low-temperature port (155) is located at the bottom of the high-temperature heat storage tank body (152). The low-temperature port (155) is led to the ground through a pipeline.

6. A geological battery energy storage system according to claim 5, characterized in that: The high-temperature heat storage medium (156) is a heat storage material spherical shell (1561) that seals a heat storage material (1562) therein.

7. A geological battery energy storage system according to claim 5, characterized in that: The high-temperature heat storage tank body (152) is completely surrounded by a heat-insulating layer (153).

8. The method for operating a geological battery energy storage system according to claim 4, characterized in that: include: Medium and low temperature heat storage process: the medium and low temperature heat storage module is operated, and the heat collected in the multi-heat source heat collection device (9) is transferred to the medium and low temperature heat storage well (7) through water as a medium for storage; when there is no waste heat source or solar energy with a high temperature at the location, and the multi-heat source heat collection device (9) cannot provide suitable heat, the backup module is activated: the water absorbs heat in the low temperature waste heat source (1) and enters the high temperature side of the heat exchanger I (3) to release heat, and the excess power of the power grid is used to drive the compressor I (4) to compress the working fluid at the low temperature side outlet of the heat exchanger I (3) into a high temperature and high pressure state, and the high temperature and high pressure working fluid enters the high temperature side of the heat exchanger II (5) to transfer the heat to the low temperature side water, and the water that absorbs the heat flows to the medium and low temperature heat storage well (7), and stores the heat in the low cost medium water in the form of sensible heat, and the working fluid after releasing heat returns to the heat exchanger I (3) through the throttle valve I (6) to continue to circulate, so as to achieve the heating 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, and the heat in the medium-low temperature heat storage well (7) is brought into the high-temperature side of the heat exchanger III (11) through water. The excess power of the power grid is used to drive the compressor II (12) to compress the working fluid at the low-temperature side outlet 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 circulating working fluid. The pressurized water after absorbing heat releases heat to the high-temperature heat storage well (15) through the heat exchanger or heat exchange pipe for storage. The working fluid that releases heat in the heat exchanger IV (13) expands through the throttle valve II (14). 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-low temperature heat storage well (7), thereby completing the cycle. During the discharge 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 operated. The heat in the high temperature heat storage well (15) is carried to the heat exchanger V (18) by the pressurized water circulating working fluid. The low boiling point working fluid absorbs heat from the heat exchanger V (18) and enters the turbine (19) to perform work and generate electricity. It 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 fluid pump (21) to absorb heat, completing the cycle.

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