Battery pack upper cover, battery pack and electric equipment

Abstract

The embodiment of the utility model provides a battery pack upper cover, a battery pack and electric equipment, and relates to the technical field of battery packs, the battery pack upper cover comprises a cover body and a heat absorption part, the cover body is provided with a non-exhaust area and at least one exhaust area, and the heat absorption part is arranged on the non-exhaust area; wherein when the temperature of the cover body is within a preset temperature range, the cover body is softened or melted, so that when the battery cell is in thermal runaway, the exhaust area can be quickly broken to release pressure, and the non-exhaust area can be kept stable within a certain time due to the heat absorption of the heat absorption piece, and is prevented from being softened or broken too early, thereby reducing the risk of fire.

Description

Technical Field

[0001] The present application relates to the technical field of battery packs, and in particular to a battery pack cover, a battery pack, and an electrical device. Background Art

[0002] The battery pack cover is installed on the battery pack tray to protect the battery cells installed between the cover and the tray, so that the battery is protected from the erosion of the external environment and provides a certain degree of buffering when the battery pack is subjected to external impact.

[0003] Among them, the plastic top cover is light in weight, has good insulation performance, strong corrosion resistance, and higher flame retardancy than metal. In addition, the plastic top cover will melt through at high temperatures, and there is no need to install an additional explosion-proof valve to discharge the gas generated by the thermal runaway battery cells in the battery pack. It is currently a more commonly used battery pack cover.

[0004] However, when the batteries in the battery pack experience thermal runaway, a large amount of high-temperature substances will be ejected, causing the plastic cover to melt on a large scale. At this time, a large amount of air will enter the battery pack and mix with the flammable materials ejected by the thermal runaway battery cells, causing the risk of fire to increase significantly. Utility Model Content

[0005] The embodiments of the present application provide a battery pack cover, a battery pack, and an electrical device to solve the problem of large-scale melting of the plastic cover of the battery pack when a battery cell experiences thermal runaway.

[0006] In a first aspect, an embodiment of the present application provides a battery pack cover, comprising a cover body and a heat absorber, wherein the cover body has a non-exhaust area and at least one exhaust area, and the heat absorber is disposed on the non-exhaust area;

[0007] Wherein, when the temperature of the cover is within a preset temperature range, the cover softens or melts.

[0008] In some possible designs, the heat absorbing element is a phase change heat absorbing element, which can absorb heat through phase change when the temperature of the phase change heat absorbing element is lower than a preset temperature.

[0009] In some possible designs, the heat absorption element is located on at least one of the inner surface and the outer surface of the non-exhaust area.

[0010] In some possible designs, the heat absorption element includes a phase change filler and a protective film, and the protective film is wrapped around the outside of the phase change filler.

[0011] In some possible designs, the protective film is an aluminum-plastic film or a plastic film.

[0012] In some possible designs, a storage cavity is provided in the non-exhaust area, and the heat absorption element is located in the storage cavity.

[0013] In some possible designs, the non-exhaust area is provided with a bursting part, which corresponds to the storage cavity. The bursting part is configured to connect the storage cavity with the outside world when the gas pressure in the storage cavity is greater than a preset pressure to discharge the gas in the storage cavity.

[0014] In some possible designs, the bursting part includes a bursting port and a sealing component. The bursting port is arranged on the non-exhaust area and is connected to the storage chamber. The sealing component is arranged on the bursting port to seal the bursting port. The sealing component is configured to open the bursting port when the gas pressure in the storage chamber is greater than a preset pressure.

[0015] In some possible designs, the burst portion includes at least one pressure relief notch provided on an outer surface of the non-exhaust area.

[0016] In some possible designs, the storage chamber is filled with a fire extinguishing element.

[0017] In some possible designs, the fire extinguishing element is located at the junction of the non-exhaust area and the exhaust area.

[0018] In some possible designs, the storage chamber includes a first storage chamber and a second storage chamber, at least one first storage chamber is provided, the first storage chamber is adjacent to the exhaust area, the fire extinguishing element is located in the first storage chamber, and the heat absorbing element is located in the second storage chamber.

[0019] In some possible designs, a protective layer is further included. The protective layer is arranged on the inner side of the cover body, and the shape of the protective layer is adapted to the shape of the inner side of the cover body.

[0020] In some possible designs, the protective layer includes at least one of a fiberglass cloth layer, a fireproof foam layer, or a mica sheet layer.

[0021] In some possible designs, a flame retardant coating layer is further included, and the flame retardant coating layer is located on at least one of the inner surface and the outer surface of the cover, or is located between the heat absorber and the inner surface or the outer surface of the cover.

[0022] The second aspect of the embodiment of the present application also provides a battery pack, including a tray and at least one battery cell, and also includes a battery pack cover as described in any one of the first aspects, wherein the battery pack cover is connected to the tray to form a accommodating cavity for accommodating the battery cell between the battery pack cover and the tray.

[0023] In some possible designs, a pressure relief device is provided on the battery cell, and the exhaust area is provided in a one-to-one correspondence with the pressure relief device.

[0024] A third aspect of an embodiment of the present application provides an electrical device, comprising a device body and a battery pack as described in any one of the second aspects, arranged on the device body.

[0025] In the battery pack cover, battery pack and electrical equipment provided in the embodiments of the present application, the battery pack cover is provided with a cover body and a heat absorber, so that the cover body has a non-exhaust area and at least one exhaust area, and the heat absorber is provided on the non-exhaust area. When a battery cell thermally runs away and ejects a large amount of high-temperature substances, the heat absorber provided in the non-exhaust area will absorb heat and reduce the temperature of the non-exhaust area, so that the non-exhaust area can maintain a relatively low temperature for a long time. There is no heat absorber in the exhaust area. After it comes into contact with the high-temperature substance, its temperature can quickly reach a preset temperature range, causing the exhaust area to soften or melt, thereby rupturing or melting through earlier and discharging the high-temperature substance. This arrangement, on the one hand, will not affect the pressure relief of the battery pack, and on the other hand, it can avoid large-scale melting of the battery pack cover, thereby effectively reducing the probability of fire caused by large-scale melting of the battery pack cover and large-scale gas entering the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0027] Figure 1 Schematic diagram of the structure of the battery pack provided in the embodiment of the present application Figure 1 ;

[0028] Figure 2 for Figure 1 Schematic diagram of the exhaust state of the battery pack;

[0029] Figure 3 A schematic diagram of the structure of a heat-absorbing member in a battery pack upper cover according to an embodiment of the present application;

[0030] Figure 4 Schematic diagram of the structure of the battery pack provided in the embodiment of the present application Figure 2 ;

[0031] Figure 5 for Figure 4 Schematic diagram of the exhaust state of the battery pack;

[0032] Figure 6 Schematic diagram of the structure of the battery pack provided in the embodiment of the present application Figure 3 ;

[0033] Figure 7 for Figure 6 Schematic diagram of the exhaust state of the battery pack;

[0034] Figure 8 A schematic diagram of the structure of the explosion part in the battery pack in Question 6;

[0035] Figure 9 Schematic diagram of the structure of the battery pack provided in the embodiment of the present application Figure 4 ;

[0036] Figure 10 for Figure 9 Schematic diagram of the exhaust state of the battery pack;

[0037] Figure 11 This is an exploded view of the battery pack provided in an embodiment of the present application.

[0038] Reference numerals:

[0039] 100 - cover; 110 - non-exhaust area; 111 - storage chamber; 112 - blasting part; 1121 - blasting opening; 1122 - blocking component; 1123 - first storage chamber; 1124 - second storage chamber; 120 - exhaust area;

[0040] 200-heat absorbing element; 210-protective film; 220-phase change filler;

[0041] 300-fire extinguishing parts;

[0042] 400-protective layer;

[0043] 500-battery cell; 510-pressure relief device;

[0044] 600-tray; 610-accommodation chamber.

[0045] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0046] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0047] The existing battery pack covers mainly include metal covers (steel covers, aluminum alloy covers, etc.), plastic covers (polypropylene, polyethylene, etc.), composite materials covers, etc.

[0048] Plastic covers are typically compression molded, offering advantages such as light weight, excellent insulation, strong corrosion resistance, higher flame retardancy than metal, and low price. Furthermore, they melt through at high temperatures, eliminating the need for additional battery pack explosion-proof valves and further reducing costs. Therefore, they are currently widely used.

[0049] However, when using a plastic cover, if the battery cells in the battery pack experience thermal runaway, they will eject large amounts of high-temperature substances, including hot smoke, particulate matter, or liquids. These high-temperature substances will be directly sprayed toward the plastic cover, continuously heating the plastic cover and making it prone to cracking. If the temperature is too high, the plastic cover may even soften or melt as a whole, causing it to melt through and leak. Although this helps to expel the runaway gas in the battery pack, the plastic cover usually melts over a large area. The large melt area allows a large amount of air to enter the battery pack. The gas entering the battery pack mixes with the flammable gas ejected by the thermal runaway battery cells, significantly increasing the risk of fire.

[0050] To avoid the above-mentioned problems, the embodiments of the present application provide a battery pack cover, a battery pack, and an electrical device. The heat-absorbing element in the battery pack cover can cool and dissipate heat in the non-exhaust area of the cover when the battery cell experiences thermal runaway and high-temperature substances spread. This can effectively maintain the strength of the battery pack cover in the early stages of thermal diffusion and reduce the degree of bulging and deformation of the battery pack cover. In the middle and late stages of thermal diffusion, the cover can be melted only in the exhaust area, thereby controlling the size of the heat-melting area of the cover, preventing or delaying battery pack fires caused by large-scale heat-melting and gas cross-flow of the cover, creating more time for escape and effectively improving the safety of battery pack use. At the same time, the battery pack cover retains the characteristic of rupture and heat-melting pressure relief at high temperatures, and still does not require the installation of an explosion-proof valve, which can reduce the cost of use.

[0051] It is understood that the battery pack cover provided in the embodiments of the present application can be applied to battery packs made of various battery cells, including but not limited to lead-acid batteries, nickel-cadmium batteries, lithium-ion batteries, lithium iron phosphate batteries, and nickel-metal hydride batteries. Furthermore, the battery pack used in the embodiments of the present application can be applied to various electrical devices that require battery power, such as electric vehicles, hybrid electric vehicles, energy storage systems, consumer electronics, medical equipment, drones, power tools, backup power systems, and other devices, which are not limited in this embodiment.

[0052] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0053] See Figure 1 and Figure 2As shown, Figure 2 The direction indicated by the middle arrow is the direction of high-temperature gas ejection during thermal runaway of the battery cell 500. This embodiment provides a battery pack cover, comprising a cover 100 and a heat sink 200. The cover 100 has a non-exhaust area 110 and at least one exhaust area 120. This can be understood as dividing the cover 100 into multiple regions, including the exhaust area 120 for rapid melting and exhaust, and the non-exhaust area 110 that needs to remain stable for a certain period of time. Of course, one or more exhaust areas 120 can be provided, or they can be located at any suitable location for exhaust, and this embodiment is not limited thereto. The heat sink 200 is provided in the non-exhaust area 110.

[0054] The cover 100 may be connected to a counterpart, such as a tray 600 , to form a receiving cavity 610 for receiving the battery cell 500 . There may be one or more battery cells 500 , which are disposed in the receiving cavity 610 .

[0055] Cover 100 is made of plastic, which can soften or melt within a preset temperature range. The preset temperature range can be determined based on the characteristics of the material or the properties of the battery cell 500. For example, the preset temperature range is 80°C to 600°C. Materials used for cover 100 include, but are not limited to, polypropylene, epoxy resin, polycarbonate, and polyethylene.

[0056] The heat absorption element 200 is made of a material with heat absorption capability. When the high-temperature substance generated by the thermal runaway of the battery cell 500 transfers heat to the non-exhaust area 110, it can absorb the heat of the non-exhaust area 110 through contact with the non-exhaust area 110, thereby reducing the temperature of the non-exhaust area 110.

[0057] The battery pack cover 100 in this embodiment is divided into a venting area 120 and a non-venting area 110. The non-venting area 110 covers a heat sink 200, which cools and dissipates heat from the non-venting area 110, preventing it from rapidly rising to its softening point. This maintains its strength and prevents it from cracking or prematurely softening. The venting area 120 is not covered by the heat sink 200. When a battery cell 500 within the battery pack experiences thermal runaway, the ejected high-temperature material heats the venting area 120, rapidly increasing its temperature and degrading its mechanical properties, making it susceptible to rupture under the influence of internal air pressure. At even higher temperatures, the venting area 120 melts and opens. Without the heat sink 200, the venting area 120 opens more quickly, allowing the high-temperature gases generated by thermal runaway to be promptly discharged from the battery pack.

[0058] That is, when the battery cell 500 of the battery pack cover provided by this embodiment fails due to thermal failure, the non-exhaust area 110 can be cooled and dissipated by the heat absorption element 200, so that it can maintain a low temperature and a certain rigidity for a long time, while the exhaust area 120 is not provided with the heat absorption element 200 and does not cool and dissipate heat, so that the exhaust area 120 can be ruptured or melted through earlier within the preset temperature range to release pressure and exhaust. Moreover, by changing the positions of the exhaust area 120 and the non-exhaust area 110 and adaptively changing the setting position of the heat absorption element 200, the effect of fixed-point and fixed-area exhaust can be achieved, thereby preventing large-scale cross-gas fire and improving the safety of battery pack use.

[0059] In some embodiments, the heat absorbing element 200 is a phase-change heat absorbing element 200 . When the temperature of the phase-change heat absorbing element 200 is lower than a preset temperature, the phase-change heat absorbing element 200 can absorb heat through phase change.

[0060] Specifically, the preset temperature is the phase transition temperature of the phase-change heat sink 200, which absorbs heat by, for example, changing from a solid to a liquid state, or from a liquid to a gas state. Of course, the phase transition temperature of the phase-change heat sink 200 must be lower than the softening temperature of the cover 100. This allows the phase-change heat sink 200 to absorb a large amount of heat through phase transition before the temperature of the non-venting area 110 reaches the softening temperature, thereby delaying the melting of the non-venting area 110.

[0061] In some embodiments, see Figure 3 As shown, when the heat absorbing element 200 is located on the inner surface or outer surface of the non-exhaust area 110, the heat absorbing element 200 includes a phase change filler 220 and a protective film 210. The protective film 210 is wrapped around the outer side of the phase change filler 220 to prevent the phase change filler 220 from being deformed or degraded due to contact with the external environment.

[0062] The protective film 210 can be connected to the surface of the non-exhaust area 110 by gluing, so that it is closely attached to the surface of the non-exhaust area 110 to enhance the heat absorption effect.

[0063] Among them, the protective film 210 includes but is not limited to aluminum-plastic film and plastic film. Of course, the melting temperature of the plastic film is preferably close to or higher than the softening temperature of the cover body 100, so as to avoid the protective film 210 melting before the cover body 100 softens, causing the phase change filler 220 to be out of contact with the non-exhaust area 110 in advance, affecting the heat absorption effect.

[0064] For example, when the cover 100 is made of polypropylene, the softening temperature thereof is about 155 degrees Celsius. In this case, a plastic film with a melting temperature higher than 150 degrees Celsius can be used as the protective film 210 .

[0065] In addition, the phase change filler 220 only needs to be able to undergo phase change and absorb heat before reaching the softening temperature of the cover body 100, that is, the phase change temperature needs to be lower than the softening temperature of the cover body 100, and it includes but is not limited to hydrogels, paraffin, fatty acids, crystalline hydrates, fatty alcohols, molten salts, water or alcohol, or a mixture of the above materials.

[0066] For example, when the cover 100 is made of polypropylene, the phase-change filler 220 can be a hydrogel. Hydrogel can undergo a phase change and absorb a large amount of heat at 120 degrees Celsius. Specifically, if the temperature of the non-venting area 110 rises to 120 degrees Celsius or above, the hydrogel will begin to phase change and absorb heat. Before the heat-absorbing components of the hydrogel are consumed, the temperature of the non-venting area 110 can be maintained for a long time, keeping the temperature of the non-venting area 110 below the softening temperature. This prevents large-scale softening, melting, collapse, or air leakage of the cover 100, thereby reducing the risk of fire or delaying the onset of fire.

[0067] In some embodiments, see Figure 1 and Figure 2 As shown, the heat absorbing member 200 is located on the outer surface of the non-exhaust area 110 and is completely attached to the outer surface of the non-exhaust area 110 to absorb heat. One or more exhaust areas 120 are inserted between the non-exhaust areas 110.

[0068] At this time, the heat absorbing element 200 can be divided into multiple blocks, each corresponding to a non-exhaust area 110, or it can be a whole with holes only opened at the location of the exhaust area 120 for avoidance.

[0069] In some embodiments, see Figure 4 and Figure 5 As shown, the heat absorbing member 200 may be disposed in different areas inside and outside the non-exhaust area 110 at the same time.

[0070] For example, near the connection area between the cover 100 and the tray 600, the heat absorption element 200 can be arranged on the inner side of the non-exhaust area 110, that is, in the accommodating cavity 610, while in other areas, the heat absorption element 200 is arranged on the outer side of the non-exhaust area 110. Solid matter in the high-temperature material may fall toward the bottom of the accommodating cavity 610 after contacting the cover 100. At this time, the heat absorption element 200 located inside the accommodating cavity 610 can directly contact the high-temperature material to absorb heat, so that the connection part between the cover 100 and the tray 600 remains stable, and the high-temperature gas will automatically move toward the weak point when encountering obstacles when spraying upward. Therefore, the high-temperature gas will not stay in one position all the time, and the heat absorption element 200 located outside the non-exhaust area 110 can continuously absorb the heat transferred from the non-exhaust area 110.

[0071] It is understandable that the heat absorbing element 200 may also be provided on both the inner surface and the outer surface of the non-exhaust area 110 , which is not limited in this embodiment.

[0072] In some embodiments, see Figure 6 and Figure 7 As shown, a storage cavity 111 is provided within the non-exhaust area 110, and a heat sink 200 is located within the storage cavity 111. In this case, the heat sink 200 can be directly filled with the phase change filler 220 within the storage cavity 111 without the need for a protective film 210. Of course, a protective film 210 is also possible, and this embodiment is not limited thereto.

[0073] When the battery cell 500 experiences thermal runaway, the high-temperature gas can be discharged through the exhaust area 120 between the storage chambers 111 without affecting the pressure relief of the battery pack.

[0074] It is understandable that when the heat absorbing element 200 is provided in the storage cavity 111 , the outer surface and the inner surface of the non-exhaust area 110 may also be provided with the heat absorbing element 200 accordingly, thereby improving the heat absorption effect.

[0075] In some embodiments, see Figure 6 As shown, the non-exhaust area 110 is provided with an explosion part 112, which corresponds to the storage chamber 111. The explosion part 112 is configured to connect the storage chamber 111 with the outside world when the gas pressure in the storage chamber 111 is greater than a preset pressure to discharge the gas in the storage chamber 111.

[0076] Of course, the explosion part 112 is arranged on the side of the non-exhaust area 110 facing the outside of the accommodating cavity 610. When the heat absorption component 200 absorbs heat during phase change and produces a large amount of gas, causing the gas pressure to rise to a preset pressure, the gas can be discharged out of the battery pack and dissipated to the environment. It can also assist the storage cavity 111 in timely depressurization to avoid explosion due to excessive gas pressure.

[0077] It is understandable that the bursting portion 112 may be a common pressure relief structure, including but not limited to an explosion-proof valve, a pressure relief valve, an exhaust valve, and a regulating valve.

[0078] In some embodiments, see Figure 8 As shown, the blasting part 112 includes a blasting port 1121 and a sealing component 1122. The blasting port 1121 is arranged on the non-exhaust area 110 and is connected to the storage chamber 111. The sealing component 1122 is arranged on the blasting port 1121 to seal the blasting port 1121. The sealing component 1122 is configured to open the blasting port 1121 when the gas pressure in the storage chamber 111 is greater than a preset pressure.

[0079] The bursting hole 1121 may be a through hole connecting the storage cavity 111 with the outside, and the through hole passes through the outer wall of the storage cavity 111 .

[0080] For example, the sealing component 1122 may be a rubber plug or the like that is inserted into the bursting hole 1121 for sealing. When the pressure in the storage chamber 111 increases to a preset pressure, the sealing component 1122 will be pushed out of the bursting hole 1121 so that the bursting hole 1121 is connected to the outside world.

[0081] Exemplarily, the sealing component 1122 can also be a substance covering the port of the bursting hole 1121 away from the storage chamber 111, such as tape. When the pressure in the storage chamber 111 increases to a preset pressure, these substances covering the bursting hole 1121 will be flushed open by the gas, allowing the bursting hole 1121 to connect with the outside world.

[0082] It is understandable that the blocking component 1122 is merely illustrated here and is not intended to limit it. Other structures that can play a similar role can be applied here and are not limited in this embodiment.

[0083] In some embodiments, the bursting portion 112 includes at least one pressure relief notch provided on the outer surface of the non-exhaust area 110. The bursting portion 112 may be formed by laser cutting, mechanical indentation, chemical etching, etc., which are not limited in this embodiment.

[0084] Stress concentration is likely to occur at the location where the pressure relief notch is set. When the pressure in the storage chamber 111 increases to a preset pressure, the location where the pressure relief notch is set will be opened to relieve pressure.

[0085] It is understandable that the pressure relief notch can be set to any shape according to needs, and this embodiment does not limit it.

[0086] In some embodiments, see Figure 9 and Figure 10 As shown, the storage cavity 111 is filled with a fire extinguishing element 300 , which is used to flow out after the cover body 100 is hot-melted to extinguish a fire.

[0087] It is understood that this embodiment does not limit the type of fire extinguishing agent used in the fire extinguishing element 300, and those skilled in the art can determine the type based on actual usage requirements. The fire extinguishing agent can be a common gaseous, liquid, or solid fire extinguishing agent, or even a combination thereof. Specifically, it includes but is not limited to hexafluoropropane, heptafluoropropane, and perfluorohexanone.

[0088] In practice, the exhaust area 120 is generally prone to fire, so the fire extinguishing element 300 can be located at the junction of the non-exhaust area 110 and the exhaust area 120. When the exhaust area 120 is broken open to release pressure, the adjacent fire extinguishing element 300 is easily affected and can flow out to extinguish the fire or block combustibles, reducing the risk of fire.

[0089] In some embodiments, see Figure 9 and Figure 10 As shown, the storage chamber 111 includes a first storage chamber 1123 and a second storage chamber 1124. At least one first storage chamber 1123 is provided. The first storage chamber 1123 is adjacent to the exhaust area 120. The fire extinguishing element 300 is located in the first storage chamber 1123, and the heat absorbing element 200 is located in the second storage chamber 1124.

[0090] Storing the fire extinguishing element 300 and the heat absorbing element 200 in the independent first storage chamber 1123 and the second storage chamber 1124 can avoid mutual influence between the two, especially preventing the performance of the fire extinguishing element from being affected by the phase change of the heat absorbing element 200.

[0091] In addition, the first storage cavity 1123 and the second storage cavity 1124 may partially overlap, that is, the two may partially overlap in an upper and lower relationship, so as to avoid rapid melting of the position of the first storage cavity 1123 due to excessive temperature.

[0092] In some embodiments, see Figure 11 As shown, the battery pack cover further includes a protective layer 400 , which is disposed on the inner side of the cover body 100 , and the shape of the protective layer 400 is adapted to the inner shape of the cover body 100 .

[0093] If the heat absorbing member 200 is disposed on the inner surface of the non-exhaust area 110 , the heat absorbing member 200 may be located between the non-exhaust area 110 and the protective layer 400 .

[0094] The protective layer 400 can reduce the impact of high-temperature substances on the cover 100 when the battery cell 500 experiences thermal runaway, thereby reducing the probability of the cover 100 being directly broken due to a strong impact.

[0095] In addition, the protective layer 400 can also be made of a material with a heat-insulating effect. For example, the protective layer 400 can include at least one of a glass fiber cloth layer, a fire-proof foam layer or a mica sheet layer. The protective layer 400 made of these materials can have a certain heat-insulating effect, preventing the temperature of the cover body 100 from rising too quickly, thereby avoiding the cover body 100 from rupturing, melting through or catching fire prematurely.

[0096] When the protective layer 400 includes two or more of a fiberglass cloth layer, a fireproof foam layer, or a mica sheet layer, they can be glued together. Of course, the protective layer 400 can also be made of other materials. This embodiment is only for illustration and not for limitation.

[0097] In some embodiments, a flame retardant coating may be applied on the inner or outer surface of the cover 100 to form a flame retardant coating layer to further reduce the probability of fire in the battery pack.

[0098] The flame retardant coating layer is formed by epoxy resin coating or other flame retardant coatings, which is not limited in this embodiment.

[0099] The present application also provides a battery pack, such as Figure 11 As shown, it includes a tray 600 and at least one battery cell 500, and also includes a battery pack cover in any of the above embodiments. The cover 100 is connected to the tray 600 to form a accommodating cavity 610 for accommodating the battery cell 500 between the cover 100 and the tray 600.

[0100] Among them, one or more battery cells 500 can be set according to usage requirements, and a pressure relief device 510 is correspondingly provided on the battery cell 500. When the battery cell 500 thermally runs away, the high-temperature material can be discharged into the accommodating cavity 610 through the pressure relief device 510, and the exhaust area 120 on the cover body 100 is set one-to-one with the pressure relief device 510. At this time, the high-temperature material will be sprayed directly toward the exhaust area 120, causing the temperature of the exhaust area 120 to rise rapidly. Although the non-exhaust area 110 will also be affected, the heat absorption component 200 will absorb heat and lower the temperature of the non-exhaust area 110, so that the non-exhaust area 110 can remain stable for a certain period of time, reducing the probability of fire, or delaying the fire of the battery pack, providing sufficient time for escape.

[0101] It can be understood that the pressure relief device 510 can be a device for controlling and releasing the pressure inside the battery cell 500, which can automatically open to release the pressure when the pressure reaches a certain value. It can be an explosion-proof valve, a pressure relief valve, an exhaust valve, a regulating valve and other devices, which are not limited in this embodiment.

[0102] The present application also provides an electrical device comprising a device body and a battery pack according to the above-described embodiment disposed on the device body. The battery pack is primarily used to power the electrical device, which may include electric vehicles, hybrid electric vehicles, energy storage systems, consumer electronics, medical devices, drones, power tools, backup power systems, and other devices requiring electricity, although this embodiment does not limit these devices.

[0103] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. It is not limited to the precise structure described above and shown in the drawings, and various modifications and variations may be made without departing from the scope of this application. The scope of this application is limited solely by the appended claims.

Claims

1. A battery pack cover, characterized in that: The invention comprises a cover body (100) and a heat absorbing member (200), wherein the cover body (100) has a non-exhaust area (110) and at least one exhaust area (120), and the heat absorbing member (200) is arranged on the non-exhaust area (110); Wherein, when the temperature of the cover body (100) is within a preset temperature range, the cover body (100) softens or melts.

2. The battery pack cover according to claim 1, characterized in that: The heat absorbing element (200) is a phase-change heat absorbing element, and when the temperature of the phase-change heat absorbing element is lower than a preset temperature, the phase-change heat absorbing element can absorb heat through phase change.

3. The battery pack cover according to claim 2, characterized in that: The heat absorbing element (200) is located on at least one of the inner surface and the outer surface of the non-exhaust area (110).

4. The battery pack cover according to claim 3, characterized in that: The heat absorbing element (200) comprises a phase-change filler (220) and a protective film (210), wherein the protective film (210) is wrapped around the outer side of the phase-change filler (220).

5. The battery pack cover according to claim 4, characterized in that: The protective film (210) is an aluminum-plastic film or a plastic film.

6. The battery pack cover according to any one of claims 1 to 5, characterized in that: A storage cavity (111) is provided in the non-exhaust area (110), and the heat absorption element (200) is located in the storage cavity (111).

7. The battery pack cover according to claim 6, characterized in that: The non-exhaust area (110) is provided with a bursting portion (112), the bursting portion (112) corresponding to the storage chamber (111), and the bursting portion (112) is configured to connect the storage chamber (111) with the outside world when the gas pressure in the storage chamber (111) is greater than a preset pressure, so as to discharge the gas in the storage chamber (111).

8. The battery pack cover according to claim 7, characterized in that: The bursting portion (112) comprises a bursting hole (1121) and a blocking component (1122); the bursting hole (1121) is arranged on the non-exhaust area (110) and is in communication with the storage chamber (111); the blocking component (1122) is arranged on the bursting hole (1121) to block the bursting hole (1121); and the blocking component (1122) is configured to open the bursting hole (1121) when the gas pressure in the storage chamber (111) is greater than a preset pressure.

9. The battery pack cover according to claim 7, characterized in that: The bursting portion (112) includes at least one pressure relief notch provided on the outer surface of the non-exhaust area (110).

10. The battery pack cover according to claim 6, characterized in that: The storage cavity (111) is filled with a fire extinguishing element (300).

11. The battery pack cover according to claim 10, characterized in that: The fire extinguishing element (300) is located at the junction of the non-exhaust area (110) and the exhaust area (120).

12. The battery pack cover according to claim 11, characterized in that: The storage chamber (111) comprises a first storage chamber (1123) and a second storage chamber (1124), at least one first storage chamber (1123) is provided, the first storage chamber (1123) is adjacent to the exhaust area (120), the fire extinguishing element (300) is located in the first storage chamber (1123), and the heat absorbing element (200) is located in the second storage chamber (1124).

13. The battery pack cover according to any one of claims 1 to 5, characterized in that: It also includes a protective layer (400), which is arranged on the inner side of the cover body (100), and the shape of the protective layer (400) is adapted to the shape of the inner side of the cover body (100).

14. The battery pack cover according to claim 13, characterized in that: The protective layer (400) includes at least one of a glass fiber cloth layer, a fireproof foam layer or a mica sheet layer.

15. The battery pack cover according to any one of claims 1 to 5, characterized in that: It also includes a flame retardant coating layer, which is located on at least one of the inner surface and the outer surface of the cover body (100), or is located between the heat absorbing element (200) and the inner surface or the outer surface of the cover body (100).

16. A battery pack comprising a tray (600) and at least one battery cell (500), characterized in that: The battery pack further comprises a battery pack cover as described in any one of claims 1 to 15, wherein the battery pack cover is connected to the tray (600) to form a receiving cavity (610) for receiving the battery cell (500) between the battery pack cover and the tray (600).

17. The battery pack according to claim 16, wherein: A pressure relief device (510) is provided on the battery core (500), and the exhaust area (120) is provided in a one-to-one correspondence with the pressure relief device (510).

18. An electrical device, characterized in that: The device comprises a device body and a battery pack as claimed in claim 16 or 17 arranged on the device body.

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