Energy storage devices

Abstract

An energy storage system according to one embodiment of the present disclosure includes: a battery rack container having a predetermined accommodation space; a plurality of battery racks, the plurality of battery racks being arranged in the battery rack container and respectively having a coolant tank in which a predetermined coolant is accommodated; and at least one flux replenishing unit, the at least one flux replenishing unit being configured to connect the coolant tanks of the plurality of battery racks.

Description

Technical Field

[0001] The present disclosure relates to an energy storage system.

[0002] This application claims priority to Korean Patent Application No. 10-2019-0088484 filed in Korea on Jul. 22, 2019, the disclosure of which is incorporated herein by reference. Background Art

[0003] Secondary batteries are highly applicable to various products and exhibit excellent electrical characteristics such as high energy density, and are commonly used not only in portable devices but also in electric vehicles (EV) or hybrid electric vehicles (HEV) driven by power supplies. Since secondary batteries can greatly reduce the use of fossil fuels and do not produce byproducts during energy consumption, they are attracting attention as a new energy source that improves environmental friendliness and energy efficiency.

[0004] Currently widely used secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, etc. The operating voltage of a unit secondary battery cell, that is, a unit battery cell, is about 2.5V to 4.5V. Therefore, if a higher output voltage is required, a plurality of battery cells can be connected in series to form a battery pack. In addition, depending on the required charge / discharge capacity of the battery pack, a plurality of battery cells can be connected in parallel to form a battery pack. Thus, the number of battery cells included in the battery pack can be set differently according to the required output voltage or the required charge / discharge capacity.

[0005] Meanwhile, when a plurality of battery cells are connected in series or in parallel to form a battery pack, a battery module including at least one battery cell is generally first constructed, and then a battery pack or battery rack is constructed by using at least one battery module and adding other components. Here, according to various voltage and capacity requirements, the energy storage system may be configured to include at least one battery rack including at least one battery module.

[0006] In a battery rack of a conventional energy storage system, when an abnormality occurs in at least one battery module among a plurality of battery modules inside a battery rack housing, a fire may occur at the battery module where the abnormality occurs.

[0007] In the event of a fire in any one battery module, if the flames and heat propagate to adjacent battery modules, additional fires may result, causing severe property damage or serious personal injury.

[0008] Therefore, it is necessary to find a way to provide an energy storage system that can more quickly prevent flames and heat from spreading to adjacent battery modules when a fire occurs in at least one of the battery modules. Summary of the invention

[0009] Technical issues

[0010] The present disclosure is directed to providing an energy storage system which can more quickly prevent flame and heat from spreading to adjacent battery modules when a fire occurs in at least one of battery modules.

[0011] Technical Solutions

[0012] In one aspect of the present disclosure, an energy storage system is provided, comprising: a battery rack container having a predetermined accommodation space; a plurality of battery racks, the plurality of battery racks being arranged in the battery rack container and respectively having a coolant tank in which a predetermined coolant is accommodated; and at least one flux replenishing unit, the at least one flux replenishing unit being configured to connect the coolant tanks of the plurality of battery racks.

[0013] Each of the plurality of battery racks may include: a plurality of battery modules, which are stacked on each other along an up-and-down direction of the battery rack and respectively have at least one battery cell; a battery rack housing, which is configured to accommodate the plurality of battery modules; a coolant tank, which is disposed to an upper side of the battery rack housing; a pipe unit, which is configured to connect the coolant tank and the plurality of battery modules; and a valve unit, which is disposed between the pipe unit and the coolant tank, and is configured to be opened when the temperature of at least one of the plurality of battery modules exceeds a predetermined temperature, so as to discharge the coolant of the coolant tank to the pipe unit, so that the coolant is supplied to the battery module exceeding the predetermined temperature.

[0014] When the valve unit is opened, the at least one flux supplementing unit may supply coolant to the coolant tank connected to the opened valve unit so as to prevent the flux of coolant input to the battery module exceeding a predetermined temperature from decreasing as the amount of coolant in the cooling tank decreases.

[0015] The at least one flux supplementing unit may have an internal flow path for flow of the coolant and connect the coolant tank of the battery rack to the coolant tank of at least one battery rack adjacent to the coolant tank of the battery rack.

[0016] The at least one flux supplementing unit may include: a connecting pipe having an internal flow path and formed in a predetermined length; and at least one flow valve provided to the connecting pipe to open or close the internal flow path.

[0017] Each of the plurality of battery racks may include at least one temperature sensor provided to a battery rack housing to sense temperatures of the plurality of battery modules.

[0018] Each of the plurality of battery racks may include a control unit electrically connected to the at least one temperature sensor, the valve unit, and the at least one flux supplementing unit to control operations of the valve unit and the flux supplementing unit.

[0019] The flux supplement unit may be provided in plurality to connect the coolant tanks of the plurality of battery racks.

[0020] The plurality of flux supplementing units may be disposed along at least one direction of the plurality of battery racks.

[0021] The pipe unit may include: a main pipe connected to the valve unit; and a plurality of module pipes connected to the main pipe and respectively connected to the battery modules.

[0022] The coolant may be water.

[0023] Beneficial effects

[0024] According to the various embodiments described above, it is possible to provide an energy storage system that can more quickly prevent flame and heat from spreading to adjacent battery modules when a fire occurs in at least one battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are used to provide a further understanding of the technical features of the present disclosure. Thus, the present disclosure should not be construed as being limited to the accompanying drawings.

[0026] Figure 1 is a view for illustrating an energy storage system according to an embodiment of the present disclosure.

[0027] Figure 2 It is used to show Figure 1 View of a battery rack of an energy storage system.

[0028] Figure 3 It is used to show Figure 2 A view of the piping unit of a battery rack of an energy storage system.

[0029] Figure 4 It is shown Figure 3 A partial cross-sectional view of a piping unit.

[0030] Figure 5 is shown along the line A-A' Figure 3 Cross-sectional view of the piping unit.

[0031] Figure 6 and Figure 7 It is used to show that according to Figure 3 Views of the hydraulic adjustment unit of various embodiments of the piping unit.

[0032] Figure 8 It is used to show Figure 2 View of the valve unit of the battery rack.

[0033] Fig. 9 It is used to show Figure 1 View of a flux replenishment unit of an energy storage system.

[0034] Fig.10 and Fig.11 It is used to show Figure 1 View of the various connection styles of flux replenishment units of an energy storage system.

[0035] Figures 12 to 17 is used to show when Figure 1 A view of the operation of an energy storage system when at least one battery module of a battery rack of the energy storage system is abnormally heated. DETAILED DESCRIPTION

[0036] By describing the embodiments of the present disclosure in detail with reference to the accompanying drawings, the present disclosure will become more apparent. It should be understood that the embodiments disclosed herein are only for a better understanding of the present disclosure, and the present disclosure can be modified in various ways. In addition, in order to easily understand the present disclosure, the accompanying drawings are not drawn according to the actual scale, but may exaggerate the size of some parts.

[0037] Figure 1 is a view for illustrating an energy storage system according to an embodiment of the present disclosure, Figure 2 It is used to show Figure 1 View of a battery rack of an energy storage system, Figure 3 It is used to show Figure 2 A view of the piping unit of a battery rack of an energy storage system, Figure 4 It is shown Figure 3 A partial cross-sectional view of the piping unit. Figure 5 is shown along the line A-A' Figure 3 A cross-sectional view of a piping unit, Figure 6 and Figure 7 It is used to show that according to Figure 3Views of the hydraulic adjustment unit of various embodiments of the piping unit, Figure 8 It is used to show Figure 2 View of the valve unit of the battery rack, Fig. 9 It is used to show Figure 1 A view of the flux replenishment unit of the energy storage system, and Fig.10 and Fig.11 It is used to show Figure 1 View of the various connection styles of flux replenishment units of an energy storage system.

[0038] refer to Figures 1 to 11 The energy storage system 1 is an energy source and can be used for household or industrial purposes. The energy storage system 1 may include a plurality of battery racks 10 , a battery rack container 50 , and a flux supplement unit 70 .

[0039] The plurality of battery racks 10 may be disposed in a battery rack container 50 explained later. The plurality of battery racks 10 may include two or more battery racks.

[0040] Each of the plurality of battery racks 10 may include a battery module 100 , a battery rack case 200 , a coolant tank 300 , a pipe unit 400 , a valve unit 500 , a temperature sensor 600 , and a control unit 700 .

[0041] The battery module 100 may be provided in plurality. The plurality of battery modules 100 may be stacked one on another along the up-down direction of the battery rack 10. Each of the plurality of battery modules 100 may include at least one battery cell 110. Hereinafter, in this embodiment, each of the plurality of battery modules 100 will be described as including a plurality of battery cells 110.

[0042] The plurality of battery cells 110 may be respectively arranged as secondary batteries. Specifically, the plurality of battery cells 110 may include at least one of a pouch-type secondary battery, a square-shaped secondary battery, and a cylindrical secondary battery. Hereinafter, in this embodiment, a case where the plurality of battery cells 110 are pouch-type secondary batteries will be described.

[0043] The battery holder case 200 may accommodate a plurality of battery modules 100. The battery holder case 200 may accommodate a plurality of battery modules 100 such that the plurality of battery modules 100 are stacked on each other in an up-and-down direction.

[0044] The coolant tank 300 may be provided to the upper side of the battery holder housing 200. The coolant tank 300 may contain a predetermined coolant therein. Thus, a receiving space capable of receiving the coolant may be provided in the coolant tank 300. Here, the coolant may be provided as a liquid coolant. As an example, the coolant may be water. Hereinafter, in this embodiment, the coolant will be described as water.

[0045] The pipe unit 400 may connect the coolant tank 300 and the plurality of battery modules 100. The pipe unit 400 may guide the coolant of the coolant tank 300, ie, water, to supply the coolant to the plurality of battery modules 100.

[0046] The pipe unit 400 may include a main pipe 410 , a module pipe 430 , and a hydraulic adjustment unit 450 .

[0047] The main duct 410 is connected to a valve unit 500 explained later, and may be elongated in an up-and-down direction of the battery holder case 200 to have a predetermined length. The main duct 410 may be spaced apart from the battery holder case 200 by a predetermined interval.

[0048] The module duct 430 is connected to the main duct 410 and may be disposed in a horizontal direction from the main duct 410. The module duct 430 is provided in plurality, and the plurality of module ducts 430 may be connected to the battery modules 100, respectively.

[0049] The plurality of module ducts 430 may be disposed to be spaced apart from each other by a predetermined distance in an up-and-down direction of the battery holder case 200. The plurality of module ducts 430 may connect the main duct 410 and the plurality of battery modules 100 to each other.

[0050] Each module conduit of the plurality of module conduits 430 may include a module valve 435 .

[0051] The module valve 435 may be provided in an internal flow path of each module pipe 430 to be opened and closed. The module valve 435 may be electrically connected to a control unit 700 explained later. Each module valve 435 may be operated according to control of the control unit 700 explained later to open or close the internal flow path of the module pipe 430.

[0052] Meanwhile, the module valve 435 may also be configured to be opened or closed in a manner different from the control of the control unit 700. As an example, the module valve 435 may be configured as a member that is installed in the module pipe 430 to close the internal flow path of the module pipe 430, and when the battery module 100 is abnormally heated, the member is melted or cut off at a preset temperature or higher to open the internal flow path of the module pipe 430.

[0053] The hydraulic pressure adjusting unit 450 is used to adjust the hydraulic pressure according to the height of the main pipeline 410, and can be arranged on the inner wall of the main pipeline 410. Specifically, the hydraulic pressure adjusting unit 450 can be arranged in plurality, and the plurality of hydraulic pressure adjusting units 450 can be respectively arranged between the plurality of module pipelines 430 in the up and down directions of the main pipeline 410.

[0054] The plurality of hydraulic adjustment units 450 may be formed to protrude from the inner wall of the main pipe 410 to the central portion of the main pipe 410 by a predetermined length. The inner diameter of the main pipe 410 having the plurality of hydraulic adjustment units 450 may be relatively reduced compared to the inner diameter of the main pipe 410 not having the plurality of hydraulic adjustment units 450. Thus, pipe loss may occur in the space of the main pipe 410 having the plurality of hydraulic adjustment units 450 between the plurality of module pipes 430. Such pipe loss offsets the pressure increased by gravity when water flows through the main pipe 410, so that water may be supplied more uniformly regardless of the height at any position of the plurality of module pipes 430.

[0055] That is, since the hydraulic pressure is adjusted according to the height of the main pipe 410 by the plurality of hydraulic pressure adjusting units 450, when water is supplied, water can be uniformly supplied at any position of the plurality of battery modules 100, including the upper side, the lower side, and the center side of the plurality of battery modules 100. Therefore, regardless of the height of the battery module 100, the plurality of hydraulic pressure adjusting units 450 can guide water to be input at a uniform flux.

[0056] Meanwhile, the plurality of hydraulic adjustment units 450 may also have other structures that can cause pipeline loss of the main pipeline 410. Figure 6 As shown in FIG. 4 , the plurality of hydraulic adjustment units 460 may be provided as a plurality of ribs protruding from the inner wall of the main pipe 410 toward the center of the main pipe 410 in a radial direction, and, as shown in FIG. Figure 7 As shown in , the plurality of hydraulic pressure adjustment units 470 may be provided in a disc shape having a plurality of holes formed therein.

[0057] The valve unit 500 is disposed between the pipe unit 400 and the coolant tank 300 , and when at least one of the plurality of battery modules 100 has a predetermined temperature or higher, the valve unit 500 may be opened to supply water in the coolant tank 300 to the pipe unit 400 , so that water is supplied to the plurality of battery modules 100 .

[0058] The valve unit 500 may include a valve body 510 and an on / off valve 530 .

[0059] The valve body 510 may connect the coolant tank 300 and the pipe unit 400. A valve flow path 515 for the flow of water may be provided inside the valve body 510.

[0060] The on / off valve 530 is configured to be opened and closed in the valve body 510, and may be provided near the coolant tank 300. The on / off valve 530 may close the valve flow path 515 when the temperature of the plurality of battery modules 100 is lower than a predetermined temperature, and may open the valve flow path 515 when the temperature of at least one battery module 100 among the plurality of battery modules 100 is higher than a predetermined temperature.

[0061] The temperature sensor 600 is provided to the battery holder housing 200 and can sense the temperature of the plurality of battery modules 100. The temperature sensor 600 may be provided in plurality. The plurality of temperature sensors 600 may be provided close to the battery modules 100, respectively.

[0062] The control unit 700 may be electrically connected to the plurality of battery modules 100, the coolant tank 300, the plurality of temperature sensors 600, the module valve 435, the valve unit 500, the flow valve 75 of the flux supplement unit 70 explained later, and various electrical components of the battery rack 10 to control operations of the battery rack 10 and the flux supplement unit 70. For example, when a fire occurs due to abnormal heating of at least one of the plurality of battery modules 100, the control unit 700 may control operations of the on / off valve 530 of the valve unit 500, operations of the module valve 435 of the module pipe 430 connected to the at least one battery module 100 where abnormal heating occurs, and operations of the flow valve 75 of the flux supplement unit 70.

[0063] Looking at the configuration of the energy storage system 1 , the battery rack container 50 can accommodate a plurality of battery racks 10 . To this end, the battery rack container 50 can have a predetermined accommodation space capable of accommodating a plurality of battery racks 10 .

[0064] The flux supplementing unit 70 may connect the coolant tanks 300 of the plurality of battery racks 10 to each other. When the valve unit 500 of at least one battery rack 10 is opened, the flux supplementing unit 70 may guide water to supply water to the coolant tank 300 connected to the opened valve unit 500, so as to prevent a decrease in the flux of water flowing into the battery module 100 at a predetermined temperature or higher when the water in the coolant tank 300 of at least one battery rack 10 in which the valve unit 500 is opened is reduced.

[0065] The flux supplementing unit 70 may connect the coolant tank 300 of at least one battery rack 10 among the plurality of battery racks 10 and the coolant tank 300 of at least one other battery rack 10 adjacent to the coolant tank 300 of the at least one battery rack 10 to each other.

[0066] Here, the flux supplementing unit 70 may be connected to the lower end of the coolant tank 300 of the battery rack 10. Thus, when the flux supplementing unit 70 is turned on, the flow of water from one coolant tank 300 to another coolant tank 300 may be naturally performed by potential energy due to gravity.

[0067] There may be provided at least one flux supplement unit 70 or a plurality of flux supplement units 70. Hereinafter, in this embodiment, the flux supplement unit 70 will be described as being provided in plurality.

[0068] A plurality of flux supplementing units 70 may be provided to connect the coolant tanks 300 of a plurality of battery racks 10 and may be arranged along at least one direction. Fig.10 As shown in , a plurality of flux supplement units 70 can be arranged in a one-dimensional shape along one direction of a plurality of battery racks 10, that is, the up-down direction. Fig.11 As shown in , the plurality of flux supplement units 80 can also be arranged in a two-dimensional shape in the up-down direction and the left-right direction according to the arrangement shape of the plurality of battery racks 10. This is only an example, and the plurality of flux supplement units 70 can be arranged in a more diverse and flexible style according to the arrangement shape of the plurality of battery racks 10.

[0069] Hereinafter, the plurality of flux supplementing units 70 will be described in more detail.

[0070] Each of the plurality of flux supplement units 70 may include a connecting pipe 71 and a flow valve 75 .

[0071] The connection pipe 71 is formed with a predetermined length and may have an inner flow path 73 for the flow of water. The connection pipe 71 may be connected to the coolant tank 300 of the adjacent battery rack 10 to communicate with the coolant tank 300 of the adjacent battery rack 10 .

[0072] At least one flow valve 75 may be provided and provided to the connection pipe 71 to open and close the internal flow path 73. The flow valve 75 may be electrically connected to the control unit 700 and may be opened and closed according to the control of the control unit 700.

[0073] Hereinafter, the operation of the energy storage system 1 when at least one battery module 100 of the battery rack 10 of the energy storage system 1 according to this embodiment is abnormally heated will be described in more detail.

[0074] Figures 12 to 17 is used to show when Figure 1 A view of the operation of an energy storage system when at least one battery module of a battery rack of the energy storage system is abnormally heated.

[0075] refer to Figure 12 to Figure 14 In the energy storage system 1, the temperature may rise rapidly due to abnormal heating of at least one of the multiple battery modules 100 of the multiple battery racks 10. When a fire occurs in the abnormally heated battery module 100, if the fire is transferred to the adjacent battery module 100, a greater risk such as explosion of the entire battery rack 10 may occur, so it is necessary to quickly block the transfer of the fire. That is, when at least one battery module 100 catches fire, it is necessary to more quickly block the spread of flames and heat toward the adjacent battery modules 100.

[0076] In this embodiment, when the temperature rises due to abnormal heating in at least one of the plurality of battery modules 100 of the battery rack 10, first, the temperature sensor 600 in the vicinity of the battery module 100 whose temperature rises due to abnormal heating, etc. may sense the temperature rise. Thereafter, if the temperature sensed by the temperature sensor 600 is higher than a preset predetermined temperature, the control unit 700 may open the on / off valve 530 of the valve unit 500 and the module valve 435 of the module pipe 430 connected to the battery module 100 heated to above the preset predetermined temperature.

[0077] When the on / off valve 530 of the valve unit 500 is opened, the water W contained in the coolant tank 300 may be supplied to the pipe unit 400 along the valve flow path 515 of the valve body 510 of the valve unit 500 .

[0078] Thereafter, the water W supplied to the main pipe 410 of the pipe unit 400 may flow toward the module pipe 430 of which the module valve 435 is opened among the plurality of module pipes 430 and be supplied to the abnormally heated battery module 100 .

[0079] Thus, water is supplied to the abnormally heated battery module 100, so that the battery module 100 having abnormal heat can be cooled more quickly. That is, in this embodiment, by using the water in the coolant tank 300, when a situation such as abnormal heating occurs, emergency cooling can be achieved by supplying water to the abnormally heated battery module 100. Thus, when at least one of the battery modules 100 catches fire, the flame and heat can be prevented from spreading to the adjacent battery modules 100 more quickly.

[0080] Meanwhile, when supplying water, the plurality of hydraulic pressure adjustment units 450 provided to the main pipe 410 may adjust the hydraulic pressure according to the height of the main pipe 410 so that water is supplied at the same flux at any position of the plurality of battery modules 100. That is, in this embodiment, regardless of the height of the stacked battery modules 100, the water W can be uniformly inputted by guiding the plurality of hydraulic pressure adjustment units 450.

[0081] In other words, when supplying water to cool the abnormally heated battery module 100, the water can be guided by the hydraulic adjustment unit 450 to input a uniform flux regardless of the stacking height, even if the stacking height is different, such as in the case where a battery module 100 at the upper side of the stacked battery modules 100 is abnormally heated, in the case where a battery module 100 at the lower side is abnormally heated, in the case where a battery module 100 at the center is abnormally heated, and so on.

[0082] By using the above-mentioned multiple hydraulic regulating units 450, water supplied when the battery module 100 stacked at the upper side is abnormally heated, water supplied when the battery module 100 stacked at the lower side is abnormally heated, and water supplied when the battery module 100 stacked at the center is abnormally heated can all be supplied with a uniform flux.

[0083] refer to Figures 15 to 17 , when the water W is supplied to the abnormally heated battery module 100 , the amount of the water W inside the coolant tank 300 that supplies the water W may decrease.

[0084] When emergency cooling is performed on the abnormally heated battery module 100, it is important to input water at the same flux within a certain period of time in order to maintain cooling performance. If the amount of water contained in the coolant tank 300 supplying water W is reduced, the hydraulic pressure is reduced, and the flux of water supplied to the abnormally heated battery module 100 may also be reduced.

[0085] In this embodiment, in this case, the control unit 700 may detect the amount of water W in the coolant tank 300 supplying the water W. If the amount of water W supplied to the coolant tank 300 of the abnormally heated battery module 100 is less than a preset predetermined amount, water W may be supplied from the coolant tank 300 of the adjacent battery rack 10 to the coolant tank 300 having the water amount less than the preset predetermined amount.

[0086] Specifically, the control unit 700 may open the flow valve 75 of the flux supplementing unit 70 to connect the coolant tank 300 having a water amount less than the preset predetermined amount with the adjacent coolant tank 300. Thus, the water W of the adjacent coolant tank 300 may flow along the internal flow path 73 of the connecting pipe 71 of the flux supplementing unit 70 and be supplied to the coolant tank 300 having a water amount less than the preset predetermined amount.

[0087] Thus, the coolant tank 300 discharging water W for emergency cooling may be supplemented with water W from an adjacent coolant tank 300 through the flux supplement unit 70 so that water W may be continuously supplied to the abnormally heated battery module 100 at the same flux for a certain period of time.

[0088] Therefore, in this embodiment, when emergency cooling is performed on the abnormally heated battery module 100, water may be input at the same flux for a specific period of time through the flux supplementing unit 70 so that cooling performance may be maintained for a specific time during emergency cooling.

[0089] According to the various embodiments described above, it is possible to provide an energy storage system 1 that can more quickly prevent flame and heat from spreading to adjacent battery modules 100 when a fire occurs in at least one battery module 100 .

[0090] Although embodiments of the present disclosure have been shown and described, it should be understood that the present disclosure is not limited to the specific embodiments described, and that those skilled in the art may make various changes and modifications within the scope of the present disclosure, and that these modifications should not be understood separately from the technical ideas and viewpoints of the present disclosure.

Claims

1. An energy storage system, comprising: A battery rack container, wherein the battery rack container has a predetermined accommodation space; a plurality of battery racks, the plurality of battery racks being disposed in the battery rack container and respectively having a coolant tank in which a predetermined coolant is contained; as well as at least one flux replenishing unit configured to connect the coolant tanks of the plurality of battery racks, Each of the battery racks further comprises a pipe unit and a valve unit, wherein the pipe unit comprises a main pipe, a plurality of module pipes and a hydraulic adjustment unit, wherein the main pipe is connected to the valve unit, the plurality of module pipes are connected to the main pipe and are respectively connected to a plurality of battery modules in the battery rack, and the hydraulic adjustment unit is disposed on an inner wall of the main pipe and is formed to protrude from the inner wall of the main pipe toward a central portion of the main pipe by a predetermined length, and is used to adjust the hydraulic pressure according to the height of the main pipe. The plurality of battery modules are stacked on each other along the up-down direction of the battery rack, and each of the plurality of battery modules has at least one battery cell; Each of the plurality of battery racks further comprises a battery rack housing configured to accommodate the plurality of battery modules; wherein the coolant tank is arranged to the upper side of the battery rack housing, the pipe unit is configured to connect the coolant tank and the plurality of battery modules, the valve unit is arranged between the pipe unit and the coolant tank, and the valve unit is configured to be opened when the temperature of at least one of the plurality of battery modules exceeds a predetermined temperature to discharge the coolant in the coolant tank to the pipe unit, so that the coolant is supplied to the battery modules exceeding the predetermined temperature.

2. The energy storage system according to claim 1, wherein: When the valve unit is opened, the at least one flux supplement unit supplies the coolant to the coolant tank connected to the opened valve unit so as to prevent a decrease in the flux of the coolant input to the battery module exceeding the predetermined temperature when the amount of the coolant in the coolant tank is reduced.

3. The energy storage system according to claim 2, wherein: The at least one flux replenishing unit has an internal flow path for flow of the coolant, and connects the coolant tank of the battery rack to the coolant tank of at least one battery rack adjacent to the coolant tank of the battery rack.

4. The energy storage system according to claim 3, wherein: The at least one flux replenishment unit comprises: a connecting pipe having the internal flow path and formed in a predetermined length; and At least one flow valve is provided to the connecting pipe to open or close the internal flow path.

5. The energy storage system according to claim 2, wherein: Each of the plurality of battery racks includes at least one temperature sensor provided to the battery rack housing to sense temperatures of the plurality of battery modules.

6. The energy storage system according to claim 5, wherein: Each of the plurality of battery racks includes a control unit electrically connected to the at least one temperature sensor, the valve unit, and the at least one flux supplementing unit to control operations of the valve unit and the flux supplementing unit.

7. The energy storage system according to claim 2, wherein: The flux supplement unit is provided in plurality to connect the coolant tanks of the plurality of battery racks.

8. The energy storage system according to claim 7, wherein: The plurality of flux supplementing units are arranged along at least one direction of the plurality of battery racks.

9. The energy storage system according to claim 1, wherein: The coolant is water.

Images