Battery pack and energy storage cabinet

Abstract

The utility model provides a battery pack and an energy storage cabinet, the battery pack comprises a shell, the shell is used for accommodating battery cells, and the wall of the shell is provided with an anti-explosion valve. Comprising a valve body and a valve cover, the valve body comprises an inner cavity, the valve cover is used for sealing the inner cavity, the valve body is provided with a ventilation opening, and the ventilation opening is used for communicating the inner cavity with the interior of a shell. A cover shell is arranged in the shell and comprises a first side plate, the projection of the first side plate on the wall covers the ventilation opening, and a plurality of first through holes are formed in the first side plate. When the battery cell is subjected to thermal runaway, solid components released by the battery cell can flow to the anti-explosion valve along with high-temperature gas, and the first side plate of the housing can block the solid components released by the battery cell during thermal runaway or electrolyte and the like, so that the solid components or the electrolyte are prevented from blocking the anti-explosion valve and damaging the anti-explosion valve. Meanwhile, high-temperature gas generated by thermal runaway of the battery cells can be released to the explosion-proof valve from the plurality of first through holes, and is further released to the outside of the battery pack through the explosion-proof valve, so that the pressure relief capability of the battery pack is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage, and particularly relates to a battery pack and an energy storage cabinet. Background Art

[0002] Battery packs are widely used in energy storage systems. In an energy storage system, electrical energy is stored through the charge and discharge of the battery pack and the stored electrical energy is supplied to users. A battery cell is the basic unit for realizing the mutual conversion of chemical energy and electrical energy in a battery pack. With the further improvement of the energy density of the battery cell, the safety problem of the battery cell has become increasingly prominent. A high-energy-density battery cell is prone to thermal runaway under conditions such as collision, overheating, extrusion, or puncture. Moreover, a large amount of heat and combustible gas will be released instantaneously when the battery cell undergoes thermal runaway. After the battery cell experiences thermal runaway, it is easy to trigger a chain of thermal runaway of a large number of battery cells, which may cause the battery pack to catch fire or even explode.

[0003] During the thermal runaway process of the battery pack, the battery cells inside the battery pack will generate high-temperature gas, and the explosion-proof valve of the battery pack will open. The high-temperature gas will quickly be released from the explosion-proof valve of the battery pack to the outside of the battery pack, reducing the risk of combustion and explosion of the battery pack. During the thermal runaway process of the battery pack, some auxiliary materials in the battery pack (for example, plastic structural parts, aluminum bars, plastic insulation parts, etc. of the battery pack and the structural parts inside the battery cell, top support pieces, etc.) will melt at high temperatures, break away from their original fixed positions, and be blown to the explosion-proof valve opening along with the high-temperature flue gas during thermal runaway, which may block the explosion-proof valve opening or cause the explosion-proof valve to deform and fail, so that the high-temperature gas inside the battery pack cannot continue to be discharged, and then cause the entire battery pack to catch fire or explode. Summary of the Utility Model

[0004] The present application provides a battery pack. A housing is provided on the wall of the battery pack where the explosion-proof valve is provided. The housing is located inside the battery pack. On the one hand, a plurality of first through holes are provided on the housing for the high-temperature gas released by the thermal runaway of the battery cells to flow through. On the other hand, the housing can block the solid components generated by the thermal runaway of the battery pack and the released electrolyte, preventing foreign objects from blocking the explosion-proof valve.

[0005] In a first aspect, the present application provides a battery pack. The battery pack includes a housing for accommodating battery cells. The housing includes four side walls and a top wall. The four side walls are arranged in pairs opposite to each other. The top wall is connected to the four side walls. The top wall and the four side walls enclose an accommodation cavity for accommodating the battery cells. An explosion-proof valve is provided on the wall of the housing, and the wall can be any one of the four side walls and the top wall. The explosion-proof valve includes a valve body and a valve cover. The valve body includes an inner cavity. The valve cover is used to seal the inner cavity. The valve body is provided with a vent hole for communicating the inner cavity with the interior of the housing. After the explosion-proof valve is opened when the internal pressure of the battery pack increases, the high-temperature gas released by the battery pack can be discharged to the outside of the battery pack through the vent hole. A cover shell is arranged inside the housing. The cover shell includes a first side plate. The projection of the first side plate on the wall covers the vent hole. The first side plate is provided with a plurality of first through holes. When a battery cell undergoes thermal runaway, the solid components released by the thermal runaway of the battery cell will flow towards the explosion-proof valve along with the high-temperature gas. The cover shell can block the solid components or electrolyte released by the thermal runaway of the battery cell, prevent the solid components or electrolyte from blocking the vent hole of the explosion-proof valve, inhibit the gas release inside the battery pack, and prevent the battery pack from catching fire and exploding. At the same time, the high-temperature gas generated by the thermal runaway of the battery cell can be released to the explosion-proof valve through the plurality of first through holes, and then released to the outside of the battery pack through the explosion-proof valve, ensuring the pressure relief ability of the battery pack.

[0006] In a possible implementation, there are a plurality of vent holes, and the plurality of first through holes and the plurality of vent holes are not arranged overlappingly. This can enhance the blocking effect of the first side plate on the solid components released by the battery cell, prevent the solid components from flying towards the explosion-proof valve through the plurality of first through holes, and thus block the vent hole.

[0007] In a possible implementation, the explosion-proof valve is arranged opposite to and spaced from the first side plate. By arranging the explosion-proof valve opposite to the first side plate, it can completely prevent the explosion-proof valve from being exposed to the periphery of the battery cell undergoing thermal runaway, enhance the blocking effect of the first side plate on the solid components released by the thermal runaway of the battery cell, and thus prevent the solid components released by the thermal runaway battery cell from flying towards the explosion-proof valve.

[0008] In a possible implementation, the valve cover is located outside the wall and is spaced apart from the wall. A second through hole is provided on the first side plate, and the wall is provided with a valve hole for installing an explosion-proof valve. The second through hole is disposed opposite to the valve hole, and the valve body passes through the valve hole and the second through hole in sequence. An elastic member is disposed inside the valve body, and the elastic member is configured to move the valve cover away from the wall when the air pressure inside the battery pack increases. When the battery pack undergoes thermal runaway, the voltage inside the battery pack will increase sharply, and the elastic member will bounce the valve cover up, so that the gas inside the battery pack is released to the outside through the vent hole of the explosion-proof valve. The distance between the first side plate and the wall can be shortened while ensuring the blocking effect of the first side plate, improving the structural compactness of the internal components of the battery pack, and enhancing the energy density of the battery pack.

[0009] In a possible implementation, there are multiple battery cells, and the multiple battery cells form a battery module. The minimum distance between the first side plate and the battery module is greater than 0. There is a gap between the first side plate and the side of the battery module close to the wall. When the battery pack undergoes thermal runaway, the released high-temperature gas can flow from this gap to the first through hole, enhancing the pressure relief capacity of the battery pack.

[0010] In a possible implementation, there are multiple battery cells, and the multiple battery cells form a battery module. The minimum distance between the valve body and the battery module is greater than 0. There is a gap between the valve body and the side of the battery module close to the wall. When the battery pack undergoes thermal runaway, the released high-temperature gas can flow from this gap to the first through hole, enhancing the pressure relief capacity of the battery pack.

[0011] In a possible implementation, the housing includes four second side plates. The four second side plates are disposed in pairs opposite to each other, perpendicular to and connected to the first side plate. At least one of the four second side plates is provided with at least one third through hole. If the solid components released by the thermal runaway of the battery cell block the first through hole of the first side plate of the housing, the high-temperature gas released by the thermal runaway of the battery cell can still be released to the outside of the battery pack through the third through hole and the explosion-proof valve, thereby enhancing the pressure relief effect of the battery pack.

[0012] In a possible implementation, one of the four second side plates is disposed opposite to the bottom wall of the battery pack, and at least one of the third through holes is provided on the one second side plate. When the solid components released during the thermal runaway of the battery cell enter the housing through the first through hole, they can fall onto the bottom wall of the battery pack through the third through hole of the one second side plate, preventing them from blocking the explosion-proof valve.

[0013] In a possible implementation, the sum of the areas of the multiple first through-holes is greater than the pressure relief area of the explosion-proof valve. When the battery cell undergoes thermal runaway, the high-temperature gas generated can be promptly released from the multiple first through-holes and the explosion-proof valve to the outside of the battery pack, ensuring the pressure relief effect of the battery pack.

[0014] In a possible implementation, the aperture diameter of each of the multiple first through-holes is greater than or equal to 2 mm. This prevents the high-temperature gas generated by the thermal runaway of the battery cell from accumulating inside the battery pack due to the too small aperture diameter of the first through-hole and being unable to be discharged quickly, ensuring the pressure relief effect of the battery pack.

[0015] In a possible implementation, the aperture diameter of each of the multiple first through-holes is less than or equal to 10 mm. This prevents the solid components released by the battery cell from being released into the housing through the first through-hole with an overly large aperture diameter, thereby blocking the explosion-proof valve.

[0016] In a possible implementation, the sum of the areas of the at least one third through-hole is greater than the pressure relief area of the explosion-proof valve. This promptly discharges the high-temperature gas inside the battery pack to the outside of the battery pack, ensuring the pressure relief effect of the battery pack.

[0017] In a possible implementation, the aperture diameter of each of the at least one third through-holes is greater than or equal to 2 mm. This further enhances the pressure relief capacity of the battery pack.

[0018] In a possible implementation, the housing includes two fixing arms. The two fixing arms are parallel to the first side plate. The two fixing arms are respectively connected to two of the four second side plates that are oppositely arranged. The two fixing arms are fixedly connected to the wall, enhancing the stability of the connection between the housing and the side wall of the battery pack.

[0019] In a second aspect, the present application provides an energy storage cabinet. The energy storage cabinet includes multiple battery packs as described in the first aspect, and the multiple battery packs are stacked. Since a housing is provided inside the battery pack, it can prevent the solid components or electrolytes released after the thermal runaway of the battery cell from blocking or damaging the explosion-proof valve, improving the safety and stability of the energy storage cabinet.

[0020] In a possible implementation, there is also an exhaust smoke channel. The exhaust smoke channel extends along the stacking direction of the multiple battery packs. The exhaust smoke channel includes multiple smoke inlet openings and a smoke outlet opening. The explosion-proof valves of the multiple battery packs correspond to the multiple smoke inlet openings one by one. After the explosion-proof valves of the multiple battery packs are opened, the multiple battery packs are in communication with the exhaust smoke channel. When a battery pack undergoes thermal runaway, the high-temperature gas released by the battery pack can be discharged into the exhaust smoke channel through the smoke inlet opening, and then discharged to the outside of the energy storage cabinet through the smoke outlet opening of the exhaust smoke channel, reducing the explosion risk of the energy storage cabinet. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural view of a battery pack provided by an embodiment of the present application;

[0022] Figure 2 is a cross-sectional view of a side structure of a battery pack provided by an embodiment of the present application;

[0023] Figure 3 is Figure 2 an enlarged schematic view of the structure at position A in

[0024] Figure 4 is a front view of the wall of a battery pack provided by an embodiment of the present application;

[0025] Figure 5 is a schematic structural view of a cover case of a battery pack installed in a housing provided by an embodiment of the present application;

[0026] Figure 6 is a schematic structural view of a cover case of a battery pack provided by an embodiment of the present application.

[0027] Reference numerals

[0028] 200 - battery pack; 210 - explosion - proof valve; 211 - valve cover; 212 - valve body; 213 - vent hole; 214 - elastic member; 220 - cover case; 221 - first through - hole; 222 - first side plate; 223 - second side plate; 224 - third through - hole; 225 - fixed arm; 226 - second through - hole; 250 - housing; 251 - wall; 252 - top wall 251; 260 - battery module 260. Detailed implementation manners

[0029] In order to make the objectives, 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. However, the exemplary embodiments can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Identical reference numerals in the figures denote identical or similar structures, and thus repeated descriptions thereof will be omitted. The words expressing positions and directions in the embodiments of the present application are all described by taking the accompanying drawings as examples, but can be changed according to needs, and all changes are included in the protection scope of the present application. The accompanying drawings in the embodiments of the present application are only used to illustrate the relative positional relationship and do not represent the true proportion.

[0030] In the embodiments of the present application, terms such as "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0031] It should be noted that specific details are described in the following description to facilitate understanding of the present application. However, the present application can be implemented in a variety of other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific implementation methods disclosed below.

[0032] For ease of understanding, the terms involved in the embodiments of the present application are first explained.

[0033] Multiple: refers to two or more than two.

[0034] "Connect" should be understood in a broad sense, for example, "connect" can be detachably connected or non-detachably connected; it can be directly connected or indirectly connected through an intermediate medium. "Fix" should also be understood in a broad sense, for example, "fix" can be directly fixed or indirectly fixed through an intermediate medium.

[0035] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0036] The following embodiments of the present application provide a battery pack, which can be used in application scenarios such as photovoltaic energy storage systems.

[0037] For example, a photovoltaic system includes photovoltaic panels, DC / DC converters, energy storage containers, and DC / AC converters. Photovoltaic panels are used to convert solar energy into DC power. The DC / DC converter is used to convert the DC power generated by the photovoltaic panels into adjustable DC power, which is then output to the energy storage container to store the power. Generally speaking, in order to increase the capacity of the energy storage container, the energy storage container includes multiple battery packs, and the energy storage container includes multiple battery compartments, each of which includes a battery cluster, and a battery cluster includes multiple stacked battery packs. The battery pack includes multiple battery cells. High-energy-density battery cells are prone to thermal runaway under conditions such as collision, overheating, extrusion, or acupuncture, and the battery cells will release a large amount of heat and flammable gas at the moment of thermal runaway. In order to prevent the battery pack from exploding due to thermal runaway of the battery cell, an explosion-proof valve is usually installed on the side wall of the battery pack. Generally, a spring-type explosion-proof valve is selected, and the opening and closing of the valve body is controlled by a spring structure. When the battery pack is in a normal state, the explosion-proof valve is in a normally closed state by the tension of the spring. When the battery cell thermally runs away, a certain pressure is generated inside the battery pack, and the spring pushes open the valve cover of the explosion-proof valve, so that the inside of the battery pack is connected to the outside world. After the air pressure in the battery pack is released, it closes, reducing the risk of explosion of the battery pack. In practice, the energy storage container will also be equipped with a smoke exhaust channel, which is connected to the battery pack through the explosion-proof valve. The smoke exhaust channel is used to discharge the high-temperature gas released by the thermal runaway of the battery pack to the outside of the cabinet.

[0038] However, during the thermal runaway of the battery pack, some auxiliary materials in the battery pack (such as plastic structural parts, aluminum bars, plastic insulation parts, etc. of the battery pack and structural parts inside the battery cell, top support sheets, etc.) will melt at high temperatures, break away from their original fixed positions, and be blown to the explosion-proof valve opening along with the high-temperature flue gas during thermal runaway, which may block the explosion-proof valve opening or cause the explosion-proof valve to deform, resulting in the failure of the explosion-proof valve. As a result, the high-temperature gas inside the battery pack cannot continue to be discharged, and then the entire battery pack catches fire or explodes. Therefore, how to prevent the explosion-proof valve from failing during the thermal runaway of the battery pack has become an urgent problem to be solved.

[0039] An embodiment of the present application provides a battery pack 200, the structure of which can be referred to Figures 1 to 3 as shown. Figure 1 is a schematic structural diagram of the battery pack 200 provided by the present application, Figure 2 is a side structural sectional view of the battery pack 200 provided by the present application, Figure 3 is Figure 2 an enlarged schematic view of the structure at A in Figure 4 and Figure 5 as shown. The battery pack 200 includes a housing 250, and the housing 250 is used to accommodate battery cells. A plurality of battery cells form a battery module 260, and the battery module 260 is located inside the housing 250. The housing 250 includes four side walls and a top wall 251. The four side walls are arranged in pairs opposite to each other. The top wall 251 is connected to the four side walls, and the top wall 251 and the four side walls form an accommodation cavity for accommodating the battery module 260. Wall 251 is one of the four side walls, and wall 251 can be the rear wall of the battery pack. The wall 251 of the housing 250 has an explosion-proof valve 210. The explosion-proof valve 210 can also be arranged on the top wall 251 according to actual needs. A cover 220 is provided inside the housing 250. The battery module 260 and the cover 220 are arranged along the X direction, and the X direction can be the length direction of the battery pack 200 or the width direction of the battery pack 200. The Z direction is the height direction of the battery pack 200. The explosion-proof valve 210 includes a valve body 212 and a valve cover 211. The valve body 212 includes an inner cavity, and the valve cover 211 is used to seal the inner cavity. The valve body 212 is provided with a vent hole 213, and the vent hole 213 is used to communicate the inner cavity and the inside of the housing. The vent hole 213 is used to communicate the inside and the outside of the battery pack 200 after the explosion-proof valve 210 is opened, and the high-temperature gas generated by the thermal runaway of the battery module 260 is discharged through the vent hole 213. A cover 220 is provided inside the housing 250. The cover 220 includes a first side plate 222. The projection of the first side plate 222 on the wall 251 covers the vent hole 213, and a plurality of first through holes 221 are provided on the first side plate 222. The structure and position of the first through holes 221 can be referred to Figure 4 is a schematic structural diagram of the wall 251 of the battery pack 200 provided by the present application, Figure 5Schematic diagram of the structure where the housing 220 of the battery pack 200 provided by the embodiment of the present application is installed on the wall 251. A housing 220 is provided between the vent 213 of the explosion-proof valve 210 and the battery cell, and the projection of the first side plate 222 in the X direction covers the vent 213 of the explosion-proof valve 210. On the one hand, when the battery cell undergoes thermal runaway, the solid components released by the thermal runaway of the battery cell will flow towards the explosion-proof valve 210 along with the high-temperature gas, as shown by the arrow direction in Figure 3 . The first side plate 222 of the housing 220 can block the solid components or electrolyte released by the thermal runaway of the battery cell, preventing the solid components or electrolyte from clogging the explosion-proof valve 210 and damaging the explosion-proof valve 210. On the other hand, a plurality of first through holes 221 are provided on the surface of the housing 220 opposite to the battery cell. The high-temperature gas generated by the thermal runaway of the battery cell can be released from the plurality of first through holes 221 to the explosion-proof valve 210, and then released to the outside of the battery pack 200 through the explosion-proof valve 210, ensuring the pressure relief effect of the explosion-proof valve 210.

[0040] To further enhance the pressure relief ability of the battery pack 200 during thermal runaway, the sum of the areas of the plurality of first through holes 221 is greater than the pressure relief area of the explosion-proof valve 210. The pressure relief area of the explosion-proof valve 210 is the area through which gas or liquid can flow after the explosion-proof valve 210 is opened. If the sum of the areas of the plurality of first through holes 221 is less than the pressure relief area after the explosion-proof valve 210 is opened, when the battery pack 200 undergoes thermal runaway, the high-temperature gas, dust, and electrolyte released by the battery cell cannot be discharged to the explosion-proof valve 210 from the plurality of first through holes 221 in time, which may be blocked inside the battery pack 200, resulting in the inability of the internal pressure of the battery pack 200 to drop in time, leading to the risk of explosion. Therefore, to ensure the pressure relief effect of the explosion-proof valve 210, the sum of the areas of the plurality of first through holes 221 should be greater than or equal to the pressure relief area after the explosion-proof valve 210 is opened.

[0041] If the aperture of the first through hole 221 is too large, the solid or electrolyte released by the thermal runaway of the battery cell will be released to the explosion-proof valve 210 through the first through hole 221, which may still clog the explosion-proof valve 210 and cause the explosion-proof valve 210 to fail. Therefore, the aperture of the first through hole 221 cannot be too large. For example, the apertures of the plurality of first through holes 221 are less than or equal to 10 mm.

[0042] If the aperture of the first through hole 221 is too small, a large amount of gas generated by the battery pack 200 in a short time cannot be quickly released outside the battery pack 200. Therefore, the apertures of the plurality of first through holes 221 cannot be too small. For example, the apertures of the plurality of first through holes 221 are greater than or equal to 2 mm.

[0043] The housing 220 can be provided in various shapes. The housing 220 can be a cuboid cavity, or a hemispherical cavity or a polyhedron cavity, etc.

[0044] To increase the pressure relief area of the explosion-proof valve 210, a plurality of vent openings 213 may be provided, and the plurality of first through holes 221 and the plurality of vent openings 213 are not arranged overlappingly. Such a design can enhance the blocking effect of the first side plate 222 on the solid components released by the battery cell, preventing the solid components from flying towards the explosion-proof valve 210 through the plurality of first through holes 221 and thus blocking the vent openings 213.

[0045] In one example, the explosion-proof valve 210 is disposed opposite to and spaced apart from the first side plate 222. That is to say, there is a distance between the first side plate 222 and the explosion-proof valve 210, further enhancing the blocking effect of the housing 220.

[0046] Continue to refer to Figure 5 , the explosion-proof valve 210 includes a valve body 212 and a valve cover 211 connected to each other. The valve cover 211 is located outside the wall and is spaced apart from the wall. A second through hole 226 is provided on the first side plate 222, and a valve hole is provided on the wall 251. The second through hole 226 is disposed opposite to the valve hole, and the valve body 212 passes through the valve hole and the second through hole 226 in sequence. An elastic member 214 is disposed inside the valve body 212, and the elastic member 214 is used to move the valve cover 211 in a direction away from the wall when the air pressure inside the battery pack 200 increases. When thermal runaway occurs inside the battery pack 200, the voltage inside the battery pack 200 will increase sharply, and the elastic force will push the valve cover 211 up, so that the gas inside the battery pack 200 is released to the outside through the vent openings 213 of the explosion-proof valve 210. Such a design can shorten the distance between the first side plate 222 and the wall 251 while ensuring the blocking effect of the first side plate 222, improve the structural compactness of the components inside the battery pack 200, and increase the energy density of the battery pack 200.

[0047] In one example, the minimum distance between the first side plate 222 and the battery module 260 is greater than 0. That is to say, there is a gap between the first side plate 222 and the side of the battery module 260 close to the wall 251. When thermal runaway occurs in the battery pack 200, the released high-temperature gas can flow from this gap to the first through holes 221, enhancing the pressure relief ability of the battery pack 200.

[0048] In one example, the shortest distance between the valve body 212 and the battery module 260 is greater than 0. That is to say, there is a gap between the valve body 212 and the side of the battery module 260 close to the wall 251. When thermal runaway occurs in the battery pack 200, the released high-temperature gas can flow from this gap to the first through holes 221, enhancing the pressure relief ability of the battery pack 200.

[0049] In one example, the housing 220 includes four second side plates 223. The four second side plates 223 are disposed opposite to each other in pairs, the four second side plates 223 are perpendicular to and connected to the first side plate 222, and at least one of the four second side plates 223 is provided with at least one third through hole 224.

[0050] Reference Figure 6 to the schematic structural diagram of the housing 220 shown. When the housing 220 is a cuboid cavity, the housing 220 may include four second side plates 223, and the four second side plates 223 are arranged in pairs opposite to each other. The four second side plates 223 are perpendicular to the wall 251, and at least one of the four second side plates 223 is provided with at least one third through hole 224. As Figure 6 shown, a plurality of third through holes 224 are respectively provided on the four second side plates 223. When a thermal runaway occurs in the battery cells in the battery pack 200, in addition to releasing high-temperature gas, the battery cells will also release dust, melted accessories, etc. These solids will spray towards the plurality of first through holes 221 along with the high-temperature gas, and may block the plurality of first through holes 221. At this time, the pressure relief rate of the battery pack 200 will be reduced. Therefore, at least one of the four second side plates 223 of the housing 220 is provided with a third through hole 224. When the first through hole 221 is blocked, the high-temperature gas in the battery pack 200 can still be released to the outside through the third through hole 224. And since the third through hole 224 is provided on the second side plate 223 of the housing 220, the solid components released by the battery cells will not fly from the third through hole 224 towards the explosion-proof valve 210, so as to be released into the housing 220 and block the explosion-proof valve 210.

[0051] One of the four second side plates 223 of the housing 220 is the second side plate 223, that is, the bottom surface of the housing 220. The second side plate 223 of the housing 220 is arranged opposite to the bottom wall of the battery pack 200, and a third through hole 224 is provided on the second side plate 223 of the housing 220. When the solid components released during thermal runaway of the battery cells enter the housing 220 through the first through hole 221, they can fall onto the bottom wall of the battery pack 200 through the third through hole 224 on the bottom surface, preventing it from blocking the explosion-proof valve 210.

[0052] It should be understood that the sum of the areas of at least one third through hole 224 is greater than the pressure relief area of the explosion-proof valve 210. If the sum of the areas of at least one third through hole 224 is smaller than the pressure relief area after the explosion-proof valve 210 is opened, then when a thermal runaway occurs in the battery pack 200, the high-temperature gas, dust, and electrolyte released by the battery cells cannot be discharged from the plurality of first through holes 221 to the explosion-proof valve 210 in time, and may be blocked inside the battery pack 200, resulting in the inability of the air pressure inside the battery pack 200 to drop in time, leading to an explosion risk. Therefore, in order to ensure the pressure relief effect of the explosion-proof valve 210, the sum of the areas of the plurality of ventilation openings should be greater than or equal to the pressure relief area after the explosion-proof valve 210 is opened.

[0053] It should be understood that in order to further enhance the pressure relief ability of the battery pack 200, the aperture area of the third through hole 224 is greater than or equal to 2 mm.

[0054] The housing 220 includes two fixing arms 225 which are parallel to the first side plate 222. The two fixing arms 225 are respectively connected to two of the four second side plates 223 which are oppositely arranged, and the two fixing arms 225 are fixedly connected to the wall 251. A plurality of screw holes can be provided on the fixing arms 225, and through the cooperation of the screw holes and bolts, the housing 220 is fixedly connected to the wall 251 of the battery pack 200. The stability of the connection between the housing 220 and the wall 251 of the battery pack 200 is enhanced, and the impact on the housing 220 during thermal runaway of the battery cells is prevented, so as to prevent the housing 220 from falling off. In other examples, the housing 220 can also be fixed by means of welding, riveting, etc.

[0055] Based on the same inventive concept, the energy storage cabinet includes a plurality of the aforementioned battery packs 200, and the plurality of battery packs 200 are stacked in the energy storage cabinet. Since the housing 220 is provided inside the battery pack 200, it can prevent the solid components or electrolytes released after thermal runaway of the battery cells from blocking or damaging the explosion-proof valve 210, and improves the safety and stability of the energy storage cabinet.

[0056] The energy storage cabinet further includes a smoke exhaust passage which extends along the stacking direction of the plurality of battery packs 200. The smoke exhaust passage includes a plurality of smoke inlet openings and a smoke outlet opening. The explosion-proof valves 210 of the plurality of battery packs 200 correspond to the plurality of smoke inlet openings one by one, and the plurality of battery packs 200 are communicated with the smoke exhaust passage after the explosion-proof valves 210 of the plurality of battery packs 200 are opened. When thermal runaway occurs in the battery pack 200, the explosion-proof valve 210 of the battery pack 200 is opened, and the high-temperature gas released by the battery pack 200 is released into the smoke exhaust passage through the explosion-proof valve 210 and the smoke inlet opening, and then is released to the outside through the smoke outlet opening.

[0057] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A battery pack, characterized in that, The battery pack includes a housing for accommodating battery cells. The housing includes four side walls and a top wall. The four side walls are arranged in pairs opposite to each other, and the top wall is connected to the four side walls. An explosion-proof valve is provided on the wall of the housing, and the wall can be any one of the four side walls and the top wall. The explosion-proof valve includes a valve body and a valve cover. The valve body includes an inner cavity, and the valve cover is used to seal the inner cavity. An air vent is provided on the valve body, and the air vent is used to communicate the inner cavity with the interior of the housing. A cover shell is provided inside the housing. The cover shell includes a first side plate, and the projection of the first side plate on the wall covers the air vent. A plurality of first through holes are provided on the first side plate.

2. The battery pack according to claim 1, characterized in that, There are a plurality of air vents, and the plurality of first through holes and the plurality of air vents are not arranged overlappingly.

3. The battery pack according to claim 1 or 2, characterized in that, The explosion-proof valve is arranged opposite to and at an interval from the first side plate.

4. The battery pack according to claim 1 or 2, characterized in that, The valve cover is located outside the wall and is spaced from the wall. A second through hole is provided on the first side plate, and a valve hole is provided on the wall. The second through hole and the valve hole are arranged opposite to each other, and the valve body passes through the valve hole and the second through hole in sequence. An elastic member is provided in the inner cavity, and the elastic member is used to move the valve cover in a direction away from the wall when the air pressure inside the battery pack increases.

5. The battery pack according to claim 4, wherein There are a plurality of battery cells, and the plurality of battery cells form a battery module. The minimum distance between the first side plate and the battery module is greater than 0.

6. The battery pack according to claim 4, characterized in that, There are a plurality of battery cells, and the plurality of battery cells form a battery module. The minimum distance between the valve body and the battery module is greater than 0.

7. The battery pack according to claim 4, characterized in that, The cover shell includes four second side plates. The four second side plates are arranged in pairs opposite to each other, and the four second side plates are perpendicular to and connected to the first side plate. At least one of the four second side plates is provided with at least one third through hole.

8. The battery pack according to claim 7, characterized in that, One of the four second side plates is arranged opposite to the bottom wall of the battery pack, and at least one of the third through holes is provided on the one second side plate.

9. The battery pack according to claim 1 or 2, characterized in that, The sum of the areas of the plurality of first through holes is greater than the pressure relief area of the explosion-proof valve.

10. The battery pack according to claim 7 or 8, characterized in that, The sum of the areas of the at least one third through hole is greater than the pressure relief area of the explosion-proof valve.

11. The battery pack according to claim 7 or 8, characterized in that, The cover shell includes two fixing arms parallel to the first side plate. The two fixing arms are respectively connected to two of the four second side plates that are arranged opposite to each other, and the two fixing arms are fixedly connected to the wall.

12. An energy storage cabinet, characterized in that, The energy storage cabinet includes a plurality of battery packs as described in any one of claims 1-11, and the plurality of battery packs are stacked.

13. The energy storage cabinet according to claim 12, characterized in that, The energy storage cabinet includes a smoke exhaust passage extending along the stacking direction of the plurality of battery packs, including a plurality of smoke inlet openings and a smoke outlet opening. The explosion-proof valves of the plurality of battery packs correspond to the plurality of smoke inlet openings one by one, and the plurality of battery packs are communicated with the smoke exhaust passage after the explosion-proof valves of the plurality of battery packs are opened.

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