Energy storage device and energy storage system

Abstract

An energy storage device and an energy storage system. The energy storage device comprises a fire-fighting module (1) and at least one battery pack (2), wherein the fire-fighting module comprises a first box (11), the first box being used for storing a fire-fighting medium, and a medium spraying port (111) being provided in an outer wall of the first box; and each battery pack comprises a second box (21) and a plurality of batteries, the second box being used for accommodating the plurality of batteries, an opening (211) being provided in an outer wall of the second box, and the opening of each second box being configured to be in communication with the medium spraying port of the fire-fighting module through a pipeline. The energy storage device and the energy storage system can ameliorate the problem of it being impossible to accurately extinguish a fire at a point of origin inside an energy storage device in the case where a fire-fighting system is arranged in a building system where the energy storage device is located.

Description

Energy storage device and energy storage system

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on February 19, 2024, with application number 202420308583.3 and application name "A Energy Storage Device and Energy Storage System", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of energy storage technology, and in particular to an energy storage device and an energy storage system. Background Art

[0004] Electronic devices often require energy storage devices to power them during use. However, energy storage devices, such as lithium-ion batteries, lead-acid batteries, and sodium batteries, can experience thermal runaway due to their own chemical reactions or external influences. Thermal runaway is dangerous and uncontrollable, so energy storage devices are often equipped with fire protection systems. Common fire protection systems are located within the building where the energy storage device is located. Fire extinguishing agents are transported to the fire point through fire protection pipes, thereby spraying the burning energy storage device. Because the spraying is applied to the exterior of the energy storage device, it is impossible to accurately extinguish the fire point inside the energy storage device. Summary of the Invention

[0005] The embodiments of the present application provide an energy storage device and an energy storage system, which can improve the problem that the fire protection system is arranged in the building system where the energy storage device is located and cannot accurately extinguish the fire point inside the energy storage device.

[0006] In the first aspect, the present application provides an energy storage device, which includes a fire protection module and at least one battery pack, wherein the fire protection module includes a first box, the first box is used to store a fire protection medium, and the outer wall of the first box is provided with a medium ejection port; each battery pack includes a second box and a plurality of batteries, the second box is used to accommodate a plurality of batteries, and the outer wall of the second box is provided with an opening, and the opening of each second box is used to communicate with the medium ejection port of the fire protection module through a pipeline. Thus, when the battery pack undergoes thermal runaway, the fire protection medium in the fire protection module can enter the inner cavity of the second box through the medium ejection port, the pipeline, and the opening of the battery pack that has undergone thermal runaway, and then use the rapid immersion of the fire protection medium (usually liquid-gas immersion) to achieve direct and efficient fire extinguishing for the fire point inside the battery pack, and at the same time, it can solve the problem of re-ignition, control the risk of spread, and also play the role of suppressing the early thermal runaway of the battery. In addition, the storage capacity of the fire protection medium is not limited by the internal space of the second box, but can be adapted to store a fire protection module with an appropriate amount of fire protection medium according to the battery runaway effect and hazard level.

[0007] In one possible embodiment, a switching control unit is provided at the medium ejection port. When each battery pack is operating normally, the switching control unit seals the medium ejection port. If at least one battery pack experiences thermal runaway, the switching control unit opens, connecting the interior of the first housing, the medium ejection port, the opening of the thermally runaway battery pack, and the interior of the second housing of the thermally runaway battery pack.

[0008] Furthermore, in one possible embodiment, a first one-way valve is installed at the opening. When a battery pack in at least one battery pack experiences thermal runaway, the on-off control unit of the fire protection module is in the open state, and the first one-way valve is in the open state. The interior of the first box, the medium ejection port, and the interior of the second box of the battery pack experiencing thermal runaway are connected. The first one-way valve only allows fluid to enter the interior of the second box from the outside, and does not allow fluid inside the second box to be discharged to the outside of the second box through the first one-way valve. This arrangement can prevent smoke generated by combustion from flowing back into the interior of the first box, thereby preventing the smoke from affecting the ejection of the fire protection medium.

[0009] In one possible embodiment, the fire protection modules and battery packs are stacked along a first direction, with each pair of adjacent boxes fixedly connected. The boxes may include either a first box or a second box. This solution can reduce the space occupied by the energy storage device in other directions.

[0010] Furthermore, in a possible embodiment, the energy storage device includes a thermal trigger component, and the thermal trigger component is used to trigger the on-off control unit to turn on.

[0011] Furthermore, in a possible embodiment, the on-off control portion includes a hot melt portion, which seals the medium ejection port.

[0012] Each secondary housing is equipped with an explosion-proof valve. The thermal trigger assembly includes a thermistor wire, and the distance between the thermistor wire and each battery pack's explosion-proof valve is within a distance threshold. One end of the thermistor wire is connected to a hot melt unit. When the thermistor wire is triggered, the hot melt unit melts under the action of the thermistor wire. This solution simplifies the control logic of the energy storage device.

[0013] Exemplarily, the distance threshold is greater than or equal to 0 and less than or equal to 30 centimeters.

[0014] Furthermore, in a possible embodiment, the energy storage device includes an isolation cover, which is fixed and sealed to each box body, and together with each box body, encloses a storage space, and the thermistor wire and each explosion-proof valve are located in the storage space. The storage space has an exhaust port, and the storage space is connected to the external environment through the exhaust port. In this solution, after a loss of control, the high-temperature flue gas triggers the combustion of the thermistor wire, and the high-temperature flue gas gathers at the exhaust port and is discharged. The storage space enclosed by the isolation cover and each box body is a non-oxygen-rich environment, which can prevent the thermistor wire from triggering sparks to ignite the high-temperature flue gas, thereby preventing the thermistor wire spark from causing adverse effects on the loss of control consequences.

[0015] Furthermore, in one possible embodiment, at least one battery pack and fire protection module are stacked, with the exhaust port located on the bottom wall of the isolation cover, and a distance between the bottom end of the thermal line and the exhaust port. In this solution, smoke is ejected downward, which helps reduce the smoke's diffusion range and, in turn, the possibility of sparks in the smoke igniting combustibles in the external environment.

[0016] In a possible embodiment, the minimum flow area of ​​the accommodating space is greater than or equal to the sum of the flow areas of the explosion-proof valves, thereby avoiding the situation where the smoke in the second box cannot be discharged smoothly due to the limitation of the flow area of ​​the accommodating space.

[0017] In one possible embodiment, the thermal trigger assembly includes at least one thermistor wire, one for each battery pack, and at least a portion of the thermistor wire is located within the second housing corresponding to the thermistor wire. The energy storage device includes a control unit, and the on / off control unit includes an on / off valve electrically connected to the control unit. When the thermistor wire is triggered, the control unit is configured to control the on / off valve to open.

[0018] In one possible embodiment, the energy storage device includes a sealed pipe, a first box body having an air inlet, and a second box body equipped with an explosion-proof valve or having a discharge port. One end of the sealed pipe is connected to the air inlet, and the other end of the sealed pipe is connected to the corresponding explosion-proof valve or discharge port. When a battery pack in at least one battery pack is in thermal runaway, the air inlet is connected to the interior of the battery pack in thermal runaway through the sealed pipe and the explosion-proof valve or discharge port of the battery pack in thermal runaway, and the on-off control unit is turned on. In this solution, the fire protection module is triggered by pressure, which is conducive to simplifying the control logic of the energy storage device.

[0019] Furthermore, in a possible embodiment, a second one-way valve is installed at the air inlet, and the second one-way valve only allows fluid to enter the interior of the first box through the second one-way valve, thereby preventing the fire-fighting medium from being sprayed out from the air inlet of the first box.

[0020] In one possible embodiment, the energy storage device includes a control unit, and the on-off control unit includes an on-off valve electrically connected to the control unit. When at least one battery pack experiences thermal runaway, the control unit controls the on-off valve to open. In this solution, the fire protection module is triggered by electrical signal force, making it more sensitive and reliable.

[0021] In one possible embodiment, the second housing includes a top wall, a bottom wall, and multiple side walls, with the top wall and the bottom wall being positioned opposite each other, and the multiple side walls being connected between the top wall and the bottom wall. The opening and the explosion-proof valve are located on two opposing side walls of the second housing, so that when thermal runaway of the battery occurs, air flows from one side to the other. While the firefighting medium is continuously injected into the interior of the second housing from the outside, the air inside the second housing is evacuated more quickly, thereby allowing oxygen inside the second housing to be expelled more quickly, thereby effectively extinguishing the fire.

[0022] In a possible embodiment, the first box body has a fire protection interface, which is connected to the interior of the first box body and is used to introduce external fire protection medium, so that the fire protection medium can be replenished into the first box body through the fire protection interface, thereby avoiding the occurrence of insufficient fire protection medium.

[0023] On the second aspect, an embodiment of the present application provides an energy storage system, which includes an energy storage device and a power converter provided by the technical solution of the first aspect, and the power converter is used to convert the electric energy output by the external power supply into power and then output it to the energy storage device. In this solution, when the battery pack has thermal runaway, the fire-fighting medium in the fire-fighting module can enter the inner cavity of the second box through the medium ejection port, the pipeline and the opening of the battery pack that has thermal runaway, and use the rapid immersion of the fire-fighting medium (usually liquid-gas immersion) to achieve direct and efficient fire extinguishing for the fire point inside the battery pack. At the same time, it can solve the problem of re-ignition, control the risk of spread, and also play a role in suppressing the early thermal runaway of the battery. In addition, the storage capacity of the fire-fighting medium is not limited by the internal space of the second box, but can be adapted to store a fire-fighting module with an appropriate amount of fire-fighting medium according to the battery runaway effect and the hazard level. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a schematic structural diagram of an energy storage device provided by the present application;

[0025] FIG2 is a schematic structural diagram of another energy storage device provided by the present application;

[0026] FIG3 is a schematic structural diagram of an energy storage device provided by the present application;

[0027] FIG4 is a schematic structural diagram of the energy storage device shown in FIG3 from another angle;

[0028] FIG5 is a schematic diagram showing the positional relationship between a thermal wire and an explosion-proof valve in an energy storage device provided by the present application;

[0029] FIG6 is a schematic diagram showing the positional relationship between a thermal wire and an explosion-proof valve in another energy storage device provided by the present application;

[0030] FIG7 is a schematic structural diagram of an energy storage device provided by the present application;

[0031] FIG8 is a schematic structural diagram of another energy storage device provided by the present application;

[0032] FIG9 is a schematic structural diagram of another energy storage device provided by the present application;

[0033] FIG10 is a top view of a fire protection module in an energy storage device in the present application;

[0034] FIG11 is a front view of the fire protection module shown in FIG10 ;

[0035] FIG12 is a top view of a fire protection module in another energy storage device in the present application;

[0036] FIG13 is a front view of the fire protection module shown in FIG12;

[0037] FIG14 is a schematic structural diagram of an energy storage system provided in this application.

[0038] Numbers: 1-firefighting module; 101-hollow part; 11-first box; 111-medium ejection port; 112-on / off valve; 113-air inlet; 115-firefighting interface; 2-battery pack; 21-second box; 211-opening; 212-first one-way valve; 213-explosion-proof valve; 3-thermal wire; 4-isolation cover; 41-exhaust port; 5-control unit; 51-third box; 6-sealing cover; 7-base; 100-energy storage device; 200-power converter; 300-external power supply; 400-electrical equipment. DETAILED DESCRIPTION

[0039] In order to facilitate understanding of the energy storage device and energy storage system provided in the embodiments of the present application, the application scenarios thereof are first introduced below. The energy storage device is used to power electronic devices so that the electronic devices can operate. The energy storage device generally includes a battery pack, which includes a case and a plurality of batteries, and the plurality of batteries are fixed in a receiving cavity of the case. When the battery pack experiences thermal runaway due to a chemical reaction of the battery or external influences, the fire point is located in the case. Therefore, spraying the battery pack from the outside cannot extinguish the fire at the source, and the fire extinguishing effect is poor.

[0040] Based on this, the embodiments of the present application provide an energy storage device and an energy storage system to solve the above problems. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings.

[0041] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of this application, the singular expressions "a", "an", "said", "above", "the", and "this" are intended to also include expressions such as "one or more", unless the context clearly indicates otherwise.

[0042] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0043] Figure 1 is a structural schematic diagram of an energy storage device 100 provided in the present application. As shown in Figure 1, an energy storage device 100 provided in this embodiment includes a fire-fighting module 1 and a battery pack 2, wherein there is at least one battery pack 2. That is to say, according to actual needs, the battery pack 2 can be one, two, three or more. Furthermore, the fire-fighting module 1 includes a first box body 11 for storing a fire-fighting medium, and the outer wall of the first box body 11 is provided with a medium ejection port 111. Each battery pack 2 includes a second box body 21 and a plurality of batteries (not shown in the figure), the second box body 21 is used to accommodate the plurality of batteries, and the outer wall of the second box body 21 is provided with an opening 211. The opening 211 of each second box body 21 is used to communicate with the medium ejection port 111 of the fire protection module 1 through a pipeline (not shown in the figure), so that when the battery pack 2 has thermal runaway, the fire protection medium in the fire protection module 1 can enter the inner cavity of the second box body 21 through the medium ejection port 111, the pipeline and the opening 211 of the battery pack 2 having thermal runaway, and then use the rapid immersion of the fire protection medium (usually liquid-gas immersion) to achieve direct and efficient fire extinguishing at the fire point inside the battery pack 2. At the same time, it can solve the problem of re-ignition, control the risk of spread, and also play the effect of suppressing early thermal runaway of the battery.

[0044] In addition, the storage capacity of the fire-fighting medium is not limited by the internal space of the second box body 21 , but the fire-fighting module 1 can be adapted to store an appropriate amount of fire-fighting medium according to the battery failure effect and hazard level.

[0045] In a specific embodiment, the type and quantity of the fire protection modules 1 can be matched according to the battery system and capacity.

[0046] It is readily understood that the first housing 11 and each of the second housings 21 are connected by piping, and at least after the fire module 1 is triggered, the pressure within the first housing 11 is greater than the pressure within the second housing 21, allowing the firefighting medium to flow into the battery pack 2 and submerge the fire source. For example, in this embodiment, the piping structure provides a seal with an IP66 rating or higher to prevent leakage of the firefighting medium.

[0047] It is worth noting that the firefighting medium mentioned in this embodiment can be an electrical firefighting agent such as perfluorohexanone, aerosol, or heptafluoropropane, or a non-conductive liquid such as pure water or distilled water. The firefighting medium serves to occupy the space in the second housing 21, expel oxygen, and cool the battery, thereby extinguishing the fire.

[0048] Exemplarily, an on-off control unit is provided at the medium ejection port of the first box body 11, and the on-off control unit controls the connection state between the medium ejection port 111 and the interior of the first box body 11. When each battery pack 2 is operating normally, the on-off control unit of the fire fighting module 1 closes the medium ejection port. This arrangement can prevent external impurities from entering the inner cavity of the first box body 11, thereby avoiding the influence of impurities on the fire extinguishing performance of the fire extinguishing medium. Furthermore, when a battery pack 2 in at least one battery pack 2 thermally runs away, the on-off control unit of the fire fighting module 1 is turned on, and the interior of the first box body 11, the medium ejection port 111, the opening 211 of the thermally runaway battery pack 2, and the interior of the second box body 21 of the thermally runaway battery pack 2 are connected, so that the fire fighting medium in the fire fighting module 1 can enter the inner cavity of the second box body 21 through the medium ejection port 111, the pipeline, and the opening 211 of the thermally runaway battery pack 2, thereby achieving direct fire extinguishing at the fire point.

[0049] Of course, in other implementations, when a battery pack 2 experiences thermal runaway, the on / off control unit of the fire protection module 1 is in the on state, and the interior of the second housing 21 of each battery pack 2 is connected to the interior of the first housing 11 via the opening 211 on the second housing 21 and the medium ejection port 111 on the first housing 11. In other words, when a battery experiences thermal runaway, the interior of each second housing 21 is submerged in the fire protection medium. This solution simplifies the structure and control logic of the fire protection device, thereby reducing device costs.

[0050] FIG2 is a schematic structural diagram of another energy storage device 100 provided in the present application. Compared with FIG1 , in the energy storage device 100 shown in FIG2 , a first one-way valve 212 is installed at the opening 211 of each second box body 21. The first one-way valve 212 only allows fluid to enter the interior of the second box body 21 from the outside, and does not allow the fluid inside the second box body 21 to be discharged to the outside of the second box body 21 through the first one-way valve 212. This arrangement can prevent the smoke generated by combustion from flowing back into the interior of the first box body 11, thereby preventing the smoke from affecting the eruption of the fire-fighting medium. It is not difficult to understand that in this case, when a battery pack 2 in at least one battery pack 2 is in thermal runaway, the on-off control unit of the fire-fighting module 1 is in an open state, the first one-way valve 212 is also in an open state, and the interior of the first box body 11, the medium ejection port 111, and the interior of the second box body 21 of the thermally runaway battery pack 2 are connected.

[0051] Next, please continue to refer to Figure 2. In some embodiments, the fire protection module 1 and each battery pack 2 are stacked along the first direction A to reduce the space occupied by the energy storage device 100 in other directions. For ease of understanding, the first box body 11 and the second box body 21 are collectively referred to as boxes below, that is, the boxes mentioned below include any one of the first box body 11 and the second box body 21. In specific implementation, when the fire protection module 1 and each battery pack 2 are stacked along the first direction A, each two adjacent boxes are fixedly connected. It is not difficult to understand that, according to actual needs, the fire protection module 1 can be arranged between the two battery packs 2, or the battery packs 2 can be arranged in sequence along the first direction A to form a battery pack unit, and the fire protection module 1 is located on one side of the battery pack unit in the first direction A. For example, the first direction A is a vertical direction. Of course, according to actual needs, the first direction A can also be other directions.

[0052] Next, the triggering method of the fire protection module 1 is described by taking the case where the fire protection module 1 and the battery packs 2 are stacked along the first direction A as an example. For example, the triggering method of the fire protection module 1 can be thermal triggering, electrical signal triggering, or pressure triggering.

[0053] FIG3 shows a schematic structural diagram of an energy storage device provided in an embodiment of the present application, and FIG4 is a schematic structural diagram of the energy storage device shown in FIG3 from another angle. The following describes the situation of heat triggering of the fire protection module in combination with FIG3 and FIG4. Specifically, in some embodiments, the energy storage device 100 includes a heat trigger component for triggering the opening of the on-off control unit, so that when a battery pack 2 has thermal runaway, the on-off control unit can be triggered by the heat trigger component and opened, and the fire protection medium in the first box 11 can enter the interior of the second box 21 through the medium ejection port 111 and the opening 211 of the second box 21 of the thermal runaway battery pack 2 to achieve fire extinguishing. For example, in a specific embodiment, the on-off control unit includes a hot melt portion (not shown in the figure), and the hot melt portion, as the name implies, is a portion that can melt when heated. It is not difficult to understand that the melting temperature of the hot melt portion depends on the melting point of its material. Furthermore, each second box 21 is equipped with an explosion-proof valve 213, and the heat trigger component includes a thermistor 3. One end of the thermosensitive wire 3 is connected to the hot melt portion, and the distance between the thermosensitive wire 3 and the explosion-proof valve 213 of each battery pack 2 is within a distance threshold. The distance threshold is a spatial distance. For example, the distance threshold can be greater than or equal to 0 and less than or equal to 30 cm. For example, the thermosensitive wire 3 is in contact with the explosion-proof valve 213 of each battery pack 2, or the spatial distance between the thermosensitive wire 3 and the explosion-proof valve 213 of each battery pack 2 is approximately 5 cm. The routing path of the thermosensitive wire 3 near the explosion-proof valve 213 of each battery pack 2 can be implemented in various ways. For example, as shown in FIG5 , the thermosensitive wire 3 is circularly encircled around the explosion-proof valve 213 of each battery pack 2 without contacting the explosion-proof valve 213. Alternatively, as shown in FIG6 , the thermosensitive wire 3 is randomly encircled around the explosion-proof valve 213 of each battery pack 2 and contacts the explosion-proof valve 213. Any part of the thermosensitive wire 3 can be triggered by high temperatures and cause combustion. The temperature of the thermosensitive wire 3 during combustion is no lower than the melting point of the heat-melting portion. As a result, after the thermosensitive wire 3 is triggered, the heat-melting portion melts under the action of the thermosensitive wire 3, thereby triggering the on-off control portion to open. The firefighting medium can be ejected from the medium ejection port 111 and enter the interior of the second housing 21 of the battery pack 2 experiencing thermal runaway, or enter the interior of the second housing 21 of all battery packs 2, gradually filling the interior of the second housing 21 of the battery packs 2. At the same time, the explosion-proof valve 213 will open, allowing the air inside the second housing 21 to be discharged to the outside of the second housing 21 through the explosion-proof valve 213 under the action of the firefighting medium, completely exhausting the oxygen in the second housing 21, thereby achieving the firefighting function.Exemplarily, the second box body includes a top wall, a bottom wall and multiple side walls, the top wall and the bottom wall are arranged opposite to each other, and the multiple side walls are connected between the top wall and the bottom wall. The opening 211 and the explosion-proof valve 213 on the second box body 21 are located on two opposite side walls of the second box body 21, so that when the battery has thermal runaway, the air flow flows from one side to the other side. In the process of continuously injecting fire-fighting medium into the interior of the second box body 21 from the outside, the air inside the second box body 21 is emptied more quickly, that is, the oxygen inside the second box body 21 is discharged faster, thereby efficiently extinguishing the fire.

[0054] Please continue to refer to Figures 3 and 4. The energy storage device 100 includes an isolation cover 4, which is fixed and sealed to each box body, and the isolation cover 4 and each box body jointly enclose a storage space, and the thermistor 3 and each explosion-proof valve 213 are all located in the storage space. In addition, the storage space has an exhaust port 41, and the storage space is connected to the external environment through the exhaust port 41. In this solution, after the loss of control, the high-temperature flue gas triggers the combustion of the thermistor 3, and the high-temperature flue gas gathers at the exhaust port 41 and is discharged. The storage space enclosed by the isolation cover 4 and each box body is a non-oxygen-rich environment, which can prevent the thermistor 3 from triggering sparks to ignite the high-temperature flue gas, thereby preventing the sparks of the thermistor 3 from causing adverse effects on the consequences of loss of control.

[0055] Further, please continue to refer to Figures 3 and 4. In some embodiments, the medium ejection port 111 of the first box body 11 and the opening 211 of the second box body 21 are located on the same side of the energy storage device 100, and the opening 211 of the second box body 21 and the explosion-proof valve 213 are located on opposite sides of the second box body 21. The thermal wire 3 is routed from the outside of the first box body 11 to be connected to the hot melt part, and the isolation cover 4 is routed from the outside of the first box body 11 and is covered on the outside of the thermal wire 3.

[0056] Please continue to refer to Figures 3 and 4. In a specific implementation method, the above-mentioned first direction A is the vertical direction, that is, the fire protection module 1 and each battery pack 2 are stacked in the vertical direction. Furthermore, the exhaust port 41 is located on the bottom wall of the isolation cover 4, and there is a distance between the bottom end of the thermal wire 3 and the exhaust port 41. In this solution, the smoke is ejected downward, which is conducive to reducing the diffusion range of the smoke, thereby reducing the possibility of sparks in the smoke igniting combustibles in the external environment. It is not difficult to understand that the distance between the bottom end of the thermal wire 3 and the exhaust port 41 is greater than 0.

[0057] Furthermore, in one possible implementation, the minimum flow area of ​​the storage space is greater than or equal to the sum of the flow areas of the explosion-proof valves 213 , thereby preventing smoke from being smoothly discharged from the second housing 21 due to the limited flow area of ​​the storage space. It should be understood that the flow area refers to the cross-sectional area of ​​the pipe perpendicular to the direction of fluid flow when the fluid flows through the pipe. The minimum flow area of ​​the storage space refers to the minimum cross-sectional area of ​​the storage space perpendicular to the direction of fluid flow when the fluid flows through the storage space.

[0058] Of course, the thermal trigger component can also be implemented in other ways. For example, in some embodiments, the thermal trigger component includes at least one thermosensitive wire 3, each battery pack 2 corresponds to at least one thermosensitive wire 3, and the thermosensitive wire 3 is at least partially located in the second box 21 corresponding to the thermosensitive wire 3. In addition, as shown in Figure 7, the energy storage device 100 includes a control unit 5, and the on-off control unit includes an on-off valve 112. The on-off valve 112 is electrically connected to the control unit 5. After the thermosensitive wire 3 is triggered, the control unit 5 is used to control the on-off valve 112 to open. Specifically, each battery pack 2 includes a control circuit (not shown in the figure), and the on-off valve 112 at the medium ejection port 111 and the control circuit of each battery pack 2 are electrically connected to the control unit 5. The thermosensitive wire 3 (not shown in Figure 7) is electrically connected to the control circuit corresponding to the thermosensitive wire 3. After the thermosensitive wire 3 is triggered, the control circuit corresponding to the triggered thermosensitive wire 3 is used to control the on-off valve 112 to open through the control unit 5. For example, when the battery pack 2 experiences thermal runaway, the temperature in the second housing 21 of the battery pack 2 continues to rise. Once it reaches the ignition point of the thermosensitive wire 3, the thermosensitive wire 3 ignites, or is triggered. This triggers a change in the control circuit, which sends an electrical signal to the control unit 5, which in turn controls the on-off valve 112 at the medium ejection port 111 to open.

[0059] FIG8 is a schematic structural diagram of another energy storage device 100 provided in an embodiment of the present application. Next, the case where the triggering mode of the fire protection module 1 is pressure-triggered will be introduced in conjunction with FIG8. As shown in FIG8, in some embodiments, the energy storage device 100 includes a sealed pipe 6, the first box body 11 has an air inlet 113, the second box body 21 is equipped with an explosion-proof valve 213 or the second box body 21 has a discharge port, one end of the sealed pipe is connected to the air inlet 113 of the first box body 11, and the other end of the sealed pipe is connected to the corresponding explosion-proof valve 213 or discharge port of the second box body 21. When a battery pack 2 in at least one battery pack 2 is in thermal runaway, the air inlet 113 is connected to the interior of the thermal runaway battery pack through the sealed pipe 6 and the explosion-proof valve or discharge port of the thermal runaway battery pack, and the on-off control unit is turned on. That is, the smoke generated when the battery pack 2 experiences thermal runaway can enter the interior of the first box body 11 through the air inlet 113 of the first box body 11, squeezing the fire-fighting agent inside the first box body 11, thereby causing the on-off control unit to be opened under the action of pressure.

[0060] In a specific implementation, the energy storage device 100 includes a sealing cover, which is fixedly and sealingly connected to each box body and defines the above-mentioned sealing channel 6 together with each box body.

[0061] Exemplarily, the first box body includes a top wall, a bottom wall, and a plurality of side walls, the top wall and the bottom wall are arranged opposite each other, and the plurality of side walls are connected between the top wall and the bottom wall. The air inlet 113 of the first box body 11 and the medium ejection port 111 are located on two opposite side walls of the first box body 11, and a second one-way valve (not shown in the figure) is installed at the air inlet 113 of the first box body 11. The second one-way valve only allows fluid to enter the interior of the first box body 11 through the second one-way valve, thereby preventing the fire-fighting medium from being ejected from the air inlet 113 of the first box body 11. Exemplarily, the air inlet 113 on the first box body 11 and the explosion-proof valve 213 installed on the second box body 21 are located on the same side to simplify the structure of the sealed pipe 6. The medium ejection port 111 on the first box body 11 and the opening 211 of the second box body 21 are located on the same side, thereby simplifying the layout of the pipeline. It is easy to understand that in this case, the on-off control unit at the medium ejection port 111 can be a membrane layer that is destroyed when the pressure reaches a preset value, or a pressure control valve that opens when the pressure reaches a preset value. The pressure acting on the on-off control unit is the pressure under the action of the firefighting medium, which can be air pressure or hydraulic pressure (such as water pressure).

[0062] Furthermore, the first box body 11 may be installed with an explosion-proof valve 213 to prevent the first box body 11 from exploding due to excessive internal pressure.

[0063] FIG9 shows a schematic structural diagram of another energy storage device 100 provided in an embodiment of the present application. Next, in conjunction with FIG9 , the case where the fire protection module 1 is triggered by an electrical signal is described. Specifically, as shown in FIG9 , the energy storage device 100 includes a control unit 5, and the on-off control unit includes an on-off valve 112. The on-off valve 112 is electrically connected to the control unit 5. When a battery pack in at least one battery pack experiences thermal runaway, the control unit 5 controls the on-off valve 112 to open.

[0064] In one specific implementation, each battery pack 2 includes a detection component (not shown). The on-off valve 112 and each detection component are electrically connected to the control unit 5. When a battery pack 2 in at least one battery pack 2 experiences thermal runaway, the detection component corresponding to the battery pack 2 experiencing thermal runaway is configured to control the on-off valve 112 to open via the control unit 5. Exemplarily, the detection component includes at least one of a pressure sensor and a temperature sensor. When a battery pack 2 experiences thermal runaway, the detection component in the battery pack 2 experiencing thermal runaway sends a signal to the control unit 5, which then controls the on-off valve 112 at the medium ejection port 111 to open.

[0065] In some embodiments, the control unit 5 is also stacked with the fire protection module 1 and each battery pack 2 along the first direction A. Specifically, each battery pack 2 is arranged sequentially along the first direction A. For ease of understanding, the entire battery pack 2 is referred to as a battery pack 2 unit. The control unit 5 is located on one side of the battery pack unit. The fire protection module 1 can be located between the control unit 5 and the battery pack unit, on the side of the control unit 5 opposite the battery pack unit, or on the side of the battery pack unit opposite the control unit 5. It is worth noting that when the fire protection module 1 is located on the side of the control unit 5 opposite the battery pack unit, or on the side of the battery pack unit opposite the control unit 5, it has no effect on the electrical connection between the battery pack 2 and the control unit 5, which helps to simplify the structural configuration of the energy storage device 100.

[0066] Exemplarily, the control unit 5 includes a third box body 51 and a control circuit arranged inside the third box body 51. The specific connection method between the control unit 5, the fire protection module 1 and each battery pack 2 is briefly described below. For ease of understanding, the first box body 11, the second box body 21 and the third box body 51 are collectively referred to as boxes. Specifically, each box body is formed with a connecting portion or is connected to a connecting ear, and the fixation between adjacent boxes is achieved by fastening the corresponding connecting portion or connecting ear with a fastener. In specific implementation, the fasteners include but are not limited to bolts, pins or rivets. The electrical connection between each battery pack 2 and the control unit 5, and the electrical connection between the fire protection module 1 and the control unit 5 in some embodiments are achieved by wiring harnesses or terminal plug-in. It is not difficult to understand that the electrical connection between each battery pack 2 and the control unit 5 can be the electrical connection between the battery pack 2 and the control unit 5, or it can be that one battery pack 2 is electrically connected to the control unit 5 through another or several other battery packs 2. When the fire protection module 1 is located between the control unit 5 and the battery pack unit, illustratively, as shown in Figures 10 to 13, the fire protection module 1 has a hollow portion 101 for avoiding the electrical connection structure. A pair of plug-in terminals are arranged in the hollow portion 101 along the first direction A, wherein one terminal is electrically connected to the control unit 5, and the other terminal is electrically connected to the battery pack 2 adjacent to the fire protection module 1. The two terminals are electrically connected via a cable, thereby achieving an electrical connection between the battery pack 2 and the control unit 5. In addition, the two terminals are electrically connected via a cable without changing the pin order, so that the connection can be completed in a stacked form when the fire protection module 1 is added.

[0067] Please continue to refer to Figure 9. In some embodiments, the first box body 11 has a fire interface 115, which is used to communicate with the interior of the first box body 11 and to introduce external fire-fighting media. In this way, the fire-fighting medium can be replenished in the first box body 11 through the fire interface 115, which can avoid the situation of insufficient fire-fighting medium. In addition, the introduction of external fire-fighting medium can also make the pressure of the fire-fighting medium in the first box body 11 higher, which is more conducive to the rapid circulation of the fire-fighting medium to the second box body 21 of the battery pack 2 where thermal runaway occurs. Exemplarily, the fire-fighting interface 115 is a marked fire-fighting interface. In this way, in an emergency, a fire truck or a fire hydrant can be connected through a standard interface, so that the fire-fighting water can be quickly delivered to the fire site and the battery can be quickly immersed. It is not difficult to understand that when each battery pack 2 is working normally, the fire-fighting interface 115 is in a closed state.

[0068] Household lithium-ion batteries typically have a minimum module capacity of 5kwh, 7kwh, or 10kwh. Different numbers of battery packs 2 can be configured based on user needs, taking into account the photovoltaic system capacity, battery investment, and electricity price savings. Furthermore, as shown in Figure 9, when the control unit 5, fire protection module 1, and battery packs 2 are stacked vertically, the energy storage device 100 may further include a base 7 located at the bottom of the energy storage device 100 to support the control unit 5, fire protection module 1, and battery packs 2.

[0069] Figure 14 is a schematic diagram of the connection structure of an energy storage system. As shown in Figure 14, the energy storage system includes the above-mentioned energy storage device 100 and the power converter 200. The power converter 200 is used to convert the electric energy output by the external power supply 300 into power and output it to the energy storage device 100, so that the energy storage device 100 can supply power to the electrical equipment 400. In this solution, when the battery pack 2 experiences thermal runaway, the firefighting medium in the firefighting module 1 can enter the inner cavity of the second box 21 through the medium ejection port 111, the pipeline and the opening 211 of the battery pack 2 where thermal runaway occurs. The rapid immersion of the firefighting medium (usually liquid-gas immersion) is used to achieve direct and efficient fire extinguishing at the fire point inside the battery pack 2. At the same time, it can solve the problem of re-ignition, control the risk of spread, and also play a role in suppressing the early thermal runaway of the battery. In addition, the storage capacity of the firefighting medium is not limited by the internal space of the second box 21, but can be adapted to store a suitable amount of firefighting medium according to the battery runaway effect and hazard level.

[0070] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. An energy storage device, characterized in that: include: A fire protection module and at least one battery pack, wherein the fire protection module includes a first box body, the first box body is used to store a fire protection medium, and an outer wall of the first box body is provided with a medium ejection port; Each of the battery packs includes a second box and multiple batteries. The second box is used to accommodate the multiple batteries. The outer wall of the second box is provided with an opening. Each opening of the second box is used to communicate with the medium ejection port of the fire protection module through a pipeline.

2. The energy storage device according to claim 1, characterized in that The medium ejection port is provided with an on-off control unit, and when each of the battery packs is operating normally, the on-off control unit closes the medium ejection port; When a battery pack in the at least one battery pack is in thermal runaway, the on-off control unit is turned on, and the interior of the first box, the medium ejection port, the opening of the battery pack in thermal runaway, and the interior of the second box of the battery pack in thermal runaway are connected.

3. The energy storage device according to claim 2, characterized in that A first one-way valve is installed at the opening. When a battery pack in the at least one battery pack is in thermal runaway, the on-off control unit of the fire protection module is in an open state, the first one-way valve is in an open state, and the interior of the first box, the medium ejection port, and the interior of the second box of the battery pack in thermal runaway are connected.

4. The energy storage device according to claim 2, characterized in that The fire protection module and each of the battery packs are stacked along a first direction, and every two adjacent boxes are fixedly connected; wherein the box includes any one of the first box and the second box.

5. The energy storage device according to claim 4, characterized in that It includes a thermal trigger component, which is used to trigger the on-off control part to turn on.

6. The energy storage device according to claim 5, characterized in that The on-off control unit includes a hot melt unit, which seals the medium ejection port; Each of the second boxes is equipped with an explosion-proof valve, the thermal trigger assembly includes a thermosensitive wire, and the distance between the thermosensitive wire and the explosion-proof valve of each battery pack is within a distance threshold; One end of the thermosensitive wire is connected to the heat-melting portion. After the thermosensitive wire is triggered, the heat-melting portion is used to melt under the action of the thermosensitive wire.

7. The energy storage device according to claim 6, characterized in that The distance threshold is greater than or equal to 0 and less than or equal to 30 centimeters.

8. The energy storage device according to claim 6, wherein: The isolation cover is fixedly and sealedly connected to each of the boxes, and together with each of the boxes, a storage space is enclosed, and the thermal wire and each of the explosion-proof valves are located in the storage space; The accommodating space has an exhaust port, and the accommodating space is communicated with the external environment through the exhaust port.

9. The energy storage device according to claim 8, characterized in that The at least one battery pack and the fire protection module are stacked, the exhaust port is located on the bottom wall of the isolation cover, and there is a distance between the bottom end of the thermal wire and the exhaust port.

10. The energy storage device according to claim 8, wherein The minimum flow area of ​​the accommodating space is greater than or equal to the sum of the flow areas of the explosion-proof valves.

11. The energy storage device according to claim 5, wherein: The thermal trigger assembly includes at least one thermosensitive wire, each battery pack corresponds to at least one thermosensitive wire, and at least a portion of the thermosensitive wire is located in the second box corresponding to the thermosensitive wire; The energy storage device includes a control unit, the on-off control unit includes an on-off valve, and the on-off valve is electrically connected to the control unit; After the thermal line is triggered, the control unit is used to control the on-off valve to open.

12. The energy storage device according to claim 4, wherein: The energy storage device includes a sealed pipe, the first box body has an air inlet, and the second box body is installed with an explosion-proof valve or has a discharge port; one end of the sealed pipe is connected to the air inlet, and the other end of the sealed pipe is connected to the corresponding explosion-proof valve or the discharge port; When a battery pack in the at least one battery pack is in thermal runaway, the air inlet is connected to the interior of the battery pack in thermal runaway through the sealed pipe and the explosion-proof valve or the discharge port of the battery pack in thermal runaway, and the on-off control unit is opened.

13. The energy storage device according to claim 12, wherein: A second one-way valve is installed at the air inlet.

14. The energy storage device according to claim 2, wherein: The energy storage device includes a control unit, the on-off control unit includes an on-off valve, and the on-off valve is electrically connected to the control unit. When a battery pack in the at least one battery pack has thermal runaway, the control unit controls the on-off valve to open.

15. The energy storage device according to any one of claims 6 to 10, 12 and 13, characterized in that: The second box body includes a top wall, a bottom wall and multiple side walls, the top wall and the bottom wall are arranged opposite to each other, and the multiple side walls are connected between the top wall and the bottom wall; the opening and the explosion-proof valve are located on two opposite side walls of the second box body.

16. The energy storage device according to any one of claims 1 to 14, characterized in that: The first box body has a fire protection interface, which is communicated with the interior of the first box body and is used to allow external fire protection media to enter.

17. An energy storage system, characterized in that: The energy storage system includes the energy storage device according to any one of claims 1 to 16 and a power converter, wherein the power converter is used to convert the electric energy output by an external power source and output the converted electric energy to the energy storage device.

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