Battery pack

Abstract

The utility model relates to the technical field of batteries, and particularly discloses a battery pack, which comprises a battery pack box body, a separation part for separating the internal space of the battery pack into a battery cavity and an exhaust passage, and a thermal runaway protection piece, a through hole for communicating the battery cavity with the exhaust passage is arranged on the separation part, and the thermal runaway protection piece covers the through hole. The protective part comprises a protective part and a weak part; the protection part comprises a connecting part used for being connected with the partition component and a deformation part connected to the inner periphery of the connecting part. And when the internal pressure of the battery monomer is released, the deformation part can deform to cover the hole wall of the through hole, so that the risk of conduction short circuit formed by a high-temperature and high-pressure eruption object and the hole wall is reduced, and the safety of the battery is further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery pack. Background Art

[0002] Existing battery packs usually include multiple battery cells, each of which is equipped with an explosion-proof valve. When a battery cell experiences thermal runaway such as overcharging, short circuiting or overheating, the pressure inside the battery cell increases. When the opening threshold of the explosion-proof valve is reached, the explosion-proof valve bursts open to ensure that the ejected material (such as high-temperature and high-pressure gas, molten material, etc.) is smoothly discharged, thereby avoiding explosion caused by excessive pressure inside the battery cell.

[0003] Furthermore, if the eruption material flows between other battery cells, its high temperature and high pressure characteristics can affect the stability of other battery cells, and even cause serious safety issues such as heat spread. Therefore, in the prior art, exhaust ducts are designed to address this issue. These ducts are used to evacuate the eruption material and prevent the negative impact of high temperature and high pressure on other battery cells. In the prior art, a partition is provided to separate the exhaust area from the space where the battery cells (cells) are installed. This allows the eruption material to enter the exhaust duct through the partition when a battery cell valve explodes.

[0004] However, because the ejected material is conductive, it can easily come into contact with other charged objects, causing a short circuit within the battery pack and, in turn, a more severe chain reaction of thermal runaway. Therefore, when the metal separator is used, both sides of the separator are insulated. However, existing processes make it difficult to ensure that the walls of the vent hole are completely covered with an insulating layer, thus posing a short circuit risk. Utility Model Content

[0005] The technical problem to be solved by the present invention is: how to solve the problem in the prior art that the metal partition component has a short circuit risk because the hole wall portion of its exhaust through hole cannot be completely insulated.

[0006] In order to solve the above technical problems, the present invention provides a battery pack, comprising:

[0007] A battery pack box, wherein a battery cell is arranged inside, and the battery cell is provided with an explosion-proof valve;

[0008] a partition member disposed inside the battery pack case and dividing the interior of the battery pack case into a battery cavity and an exhaust passage, the partition member being provided with a through hole connecting the battery cavity and the exhaust passage, the battery cell being disposed in the battery cavity; and

[0009] a thermal runaway protection member, disposed on a side of the partition member close to the battery cavity and covering the through hole, the thermal runaway protection member comprising a protection portion and a weakened portion, the weakened portion being disposed corresponding to the explosion-proof valve;

[0010] The protective portion includes a connecting portion and a deformable portion, wherein the deformable portion is connected to the outer periphery of the weak portion; the connecting portion is connected to the outer periphery of the deformable portion and is connected to the partition component; and the side of the connecting portion away from the deformable portion is connected to the partition component;

[0011] When the battery cell releases internal pressure, the ejected matter of the battery cell can be discharged into the exhaust channel through the explosion-proof valve, the weak portion and the through hole, and the deformable portion is deformed to cover the hole wall of the through hole.

[0012] Further preferably, the orthographic projections of the weak portions on the partitioning components are all located within the corresponding through holes.

[0013] Further preferably, along the thickness direction of the partition member, the weak portion and the explosion-proof valve have orthographic projections on the partition member, and the orthographic projection of the weak portion is located within the orthographic projection of the explosion-proof valve.

[0014] Further preferably, an orthographic projection of the deformation portion on the partition member along a thickness direction of the partition member falls into the through hole.

[0015] Further preferably, along the thickness direction of the partition component, the deformation portion and the explosion-proof valve have a positive projection on the partition component, the positive projection of the deformation portion is annular, and in the radial direction of the through hole, the distance between the inner periphery of the positive projection of the deformation portion and the outer periphery of the positive projection of the explosion-proof valve is D1, and 0.5mm≤D1≤3mm.

[0016] Further preferably, in the radial direction of the through hole, the length of the deformation portion extending toward the middle of the through hole is equal to or greater than the thickness of the hole wall of the through hole, so that the deformation portion can completely cover the hole wall of the through hole after deformation.

[0017] Further preferably, in the radial direction of the through hole, the length L1 of the deformation portion extending toward the middle of the through hole is 1mm≤L1≤7mm;

[0018] and / or

[0019] The thickness of the partition member is L2, and 1mm≤L2≤7mm.

[0020] Further preferably, the orthographic projection area of ​​the deformation portion in the through hole is larger than the area of ​​the hole wall of the through hole.

[0021] Further preferably, the protective portion and the weak portion are integrally formed, a notch is provided at the connection between the weak portion and the protective portion, and the weak portion is configured to be destroyed along the notch when the battery cell releases internal pressure.

[0022] Further preferably, a notch is provided in a middle area of ​​the weak portion, and the weak portion is configured to be destroyed along the notch when the internal pressure of the battery cell is released.

[0023] Further preferably, the notch is a closed notch or a non-closed notch.

[0024] Further preferably, a fold is provided at the junction of the connecting portion and the deformable portion, and the deformable portion is deformed along the fold.

[0025] Further preferably, when the thermal runaway protection element is projected in the direction of the partition component, the projection of the fold coincides with the edge of the through hole.

[0026] Further preferably, the through hole is a polygonal hole, and the fold includes multiple straight line marks.

[0027] Further preferably, the fold is provided on a side of the thermal runaway protection element facing the through hole, and a thickness of the fold is thinner than that of the deformation portion and / or the connection portion.

[0028] Further preferably, the thermal runaway protection component is an insulating high-temperature resistant protection component.

[0029] Further preferably, the insulating high-temperature resistant protective member is a ceramic material protective member, a fiber material protective member or a silicate material protective member.

[0030] Further preferably, the partition component is a liquid cooling plate.

[0031] Compared with the prior art, the battery pack provided by the present invention has the following advantages:

[0032] The utility model provides a battery pack, wherein a partition component divides the interior of the battery pack into a battery cavity and an exhaust channel, and a through hole connecting the battery cavity and the exhaust channel is provided on the partition component, a thermal runaway protection member is provided to cover the through hole, and the thermal runaway protection member is configured to include a protection portion and a weak portion. When thermal runaway occurs in a battery cell, the weak portion is destroyed, so that the ejecta can pass smoothly into the exhaust channel. Moreover, since the protection portion includes a connecting portion and a deformation portion, the deformation portion can cover the hole wall of the through hole during thermal runaway, thereby reducing the risk of a short circuit between the high-temperature and high-pressure ejecta and the hole wall, thereby improving the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1It is a structural schematic diagram of the thermal runaway protection component of the present invention.

[0034] Figure 2 It is a structural schematic diagram of the second notch of the present invention.

[0035] Figure 3 It is a structural schematic diagram of the thermal runaway protection component and the separation component of the utility model.

[0036] Figure 4 This utility model Figure 3 Enlarged schematic diagram of point A in the middle.

[0037] Figure 5 It is a structural schematic diagram of the battery pack of the present invention.

[0038] Figure 6 It is a partial cross-sectional view of the battery pack of the present invention.

[0039] Figure 7 This is an assembly diagram of the battery cell, separator and thermal runaway protection component of the present invention.

[0040] In the picture:

[0041] 10. Thermal runaway protection element; 11. Protection portion; 111. Connecting portion; 112. Deformed portion; 113. Crease; 12. Weak portion; 13. Notch; 131. First notch; 132. Second notch;

[0042] 20. Battery pack body; 21. Battery cell; 211. Explosion-proof valve; 22. Battery cavity; 23. Exhaust channel;

[0043] 30. Partitioning member; 31. Through hole. DETAILED DESCRIPTION

[0044] The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0045] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like used in the present invention to indicate the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0046] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this utility model, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0047] Furthermore, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model in their respective contexts.

[0048] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0049] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0050] like Figures 1-6 As shown, this embodiment provides a battery pack, including a battery pack box 20, a partition component 30 and a thermal runaway protection component 10.

[0051] In some embodiments, a battery cell 21 is provided inside the battery pack case 20, and the battery cell 21 is provided with an explosion-proof valve 211; the battery pack case 20 is generally a box structure formed by an upper cover, a bottom plate and a frame, and a partition component 30 is provided inside the battery pack case 20. The partition component 30 divides the interior of the battery pack case 20 into a battery cavity 22 and an exhaust channel 23. The battery cavity 22 is used to place the battery cell 21, and the exhaust channel 23 is used to evacuate the ejected material of the battery cell 21 in time when thermal runaway occurs in the battery cell 21, thereby avoiding causing a more serious thermal runaway chain reaction.

[0052] In some embodiments, a through hole 31 connecting the battery cavity 22 and the exhaust channel 23 is provided on the partition component 30. The thermal runaway protection component 10 is placed in the battery cavity 22 and connected to the partition component 30. The thermal runaway protection component 10 is used to cover the through hole 31 when the battery cell 21 erupts in thermal runaway.

[0053] In some embodiments, the thermal runaway protection element 10 includes a protective portion 11 and a weakened portion 12. The protective portion 11 is formed around the weakened portion 12, and the weakened portion 12 is configured to be destroyed when the battery cell 21 releases internal pressure. The weakened portion 12 is designed to more easily break through or form a gap when the battery cell 21 erupts, allowing the erupted material to pass through the gap and enter the exhaust passage 23, thereby avoiding the situation where the pressure relief valve should be opened but the protective element cannot be broken through. The protective portion 11 connects the weakened portion 12 and the separator 30, and can prevent the erupted material from escaping through the gap between the battery cell 21 and the separator 30 and affecting other normal battery cells 21.

[0054] The protective portion 11 includes a connecting portion 111 and a deformable portion 112 , wherein the deformable portion 112 is connected to the periphery of the weak portion 12 ; the connecting portion 111 is connected to the periphery of the deformable portion 112 , and the side of the connecting portion 111 away from the deformable portion 112 is connected to the partition component 30 .

[0055] Specifically, the weak portion 12 is arranged corresponding to the through hole 31, and the explosion-proof valve 211 of the battery cell 21 corresponds to the weak portion 12. When the battery cell 21 releases internal pressure, the weak portion 12 can allow the ejected material of the battery cell 21 to pass through and be discharged from the through hole 31 to the exhaust channel 23, and the deformation portion 112 can be deformed to at least partially cover the hole wall of the through hole 31.

[0056] Among them, the deformation portion 112 is deformed under pressure to cover the hole wall of the through hole 31, which means that the deformation portion 112 can block the hole wall in the radial direction extending along the axial hole wall in the through hole 31, including the situation that the deformation portion 112 is completely attached to the hole wall, or the deformation portion 112 is bent but there is a gap with the hole wall.

[0057] The present invention provides a battery pack, which uses a partition component 30 to divide the interior of the battery pack into a battery cavity 22 and an exhaust channel 23, and is provided with a through hole 31 connecting the battery cavity 22 and the exhaust channel 23 on the partition component 30. A thermal runaway protection member 10 is provided to cover the through hole 31, and the thermal runaway protection member 31 is provided with a protection portion 11 and a weak portion 12. When the battery cell 21 has thermal runaway, the weak portion 12 is destroyed, so that the ejecta can pass smoothly into the exhaust channel 23. Moreover, since the protection portion 11 includes a connecting portion 111 and a deformable portion 112, the deformable portion 112 can cover the hole wall of the through hole 31 during thermal runaway, thereby reducing the risk of a short circuit between the high-temperature and high-pressure ejecta and the hole wall, thereby improving the safety of the battery.

[0058] In some embodiments, the orthographic projections of the weak portions 12 on the partition component 30 are all located within the corresponding through holes 31, and the orthographic projections of the explosion-proof valves 211 of the battery cells 21 on the partition component 30 are located within the corresponding weak portions 12; in this way, when the weak portions 12 are destroyed when the battery cells release internal pressure, the ejected materials of the battery cells 21 can be promptly evacuated into the exhaust channel 23 through the through holes 31, thereby avoiding causing a more serious thermal runaway chain reaction.

[0059] Furthermore, along the thickness direction of the partition member 30, both the weak portion 12 and the explosion-proof valve 211 have orthographic projections on the partition member 30, and the orthographic projection of the weak portion 12 lies within the orthographic projection of the explosion-proof valve 211. Specifically, the projected area of ​​the weak portion 12 is smaller than the area of ​​the explosion-proof valve 211, and the two areas are in a corresponding relationship. This ensures that when the explosion-proof valve 211 is actuated, the weak portion 12 is impacted and ruptured, ensuring smooth penetration.

[0060] In some embodiments, the protective portion 11 includes a connecting portion 111 for connecting to the partition component 30 and a deformable portion 112 connected to the inner periphery of the connecting portion 111, wherein the weak portion 12 is connected to the inner periphery of the deformable portion 112 for corresponding to the explosion-proof valve 211 of the battery cell 21. When the battery cell 21 releases internal pressure, the weak portion 12 can be destroyed to allow the ejected material of the battery cell 21 to be discharged from the through hole; in addition, the deformable portion 112 is a closed-loop structure, and the deformable portion 112 protrudes from the through hole in the radial direction of the through hole to form a circle of protruding circumference. The deformable portion 112 is configured to be pressurized to produce deformation toward the through hole when the explosion-proof valve 211 erupts, and can cover the hole wall of the through hole. Among them, since the protective part 11 includes the connecting part 111 and the deforming part 112, the deforming part 112 can be deformed during thermal runaway to form a circle of protruding edges for completely covering the hole wall of the through hole 31, thereby reducing the risk of high-temperature and high-pressure eruptions forming a short circuit with the hole wall, thereby improving the safety of the battery.

[0061] Specifically, deformable portion 112 and explosion-proof valve 211 have an orthographic projection on partition member 30, and the inner periphery of the orthographic projection of deformable portion 112 falls within the orthographic projection of explosion-proof valve 211. In the radial direction of through-hole 31, the distance D1 between the inner periphery of the orthographic projection of deformable portion 112 and the outer periphery of the orthographic projection of explosion-proof valve 211 satisfies 0.5 mm ≤ D1 ≤ 3 mm.

[0062] For example, D1 can be 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 2mm, 2.5mm, or 3mm. Distance D1 represents the radial distance that the deformable portion 112 protrudes from the explosion-proof valve 211. If this distance is too small, the deformable portion will not be effectively impacted when the explosion-proof valve 211 is opened, resulting in insufficient deformation of the deformable portion. If this distance is too large, the valve may be blocked, resulting in poor exhaust in the event of thermal runaway of the battery cell.

[0063] In some embodiments, a fold 113 is provided at the junction of the connecting portion 111 and the deformable portion 112, so that the deformable portion 112 can bend along the fold 113 under the disturbance of the exhaust airflow and the ejected material from the battery cell explosion valve. The deformable portion 112 can be made of an elastic material, automatically rebounding to its initial state after the ejection ends; or it can be made of a rigid material, so that the deformable portion 112 remains bent after the ejection ends.

[0064] In some embodiments, when the battery cell 21 thermally runs away, in order to further improve the deformation effect of the deformation portion 112, in the direction in which the thermal runaway protection member 10 is projected onto the partition component 30, the projection of the fold 113 coincides with the edge of the through hole 31, so that the deformation portion 112 can be quickly deformed after being compressed to form a circle of protruding edges for completely covering the hole wall of the through hole 31.

[0065] In some embodiments, the through hole 31 can be a circular hole, an elliptical hole or a polygonal hole. When the through hole 31 can be a circular hole, the fold 113 is a circular fold. When the through hole 31 is an elliptical hole, the fold 113 is a corresponding elliptical fold. When the through hole 31 is a polygonal hole, the fold 113 includes multiple straight line marks.

[0066] In some embodiments, the fold 113 is formed by thinning the thickness of the thermal runaway protection member 10 toward the through hole 31, so that the deformation portion 112 can quickly deform after being compressed to cover the hole wall of the through hole 31, thereby reducing the risk of high-temperature and high-pressure eruptions forming a short circuit with the hole wall, thereby improving the safety of the battery.

[0067] In some embodiments, reference Figure 1The protective portion 11 and the weak portion 12 are integrally formed to form a sheet structure. A notch 13 is provided at the connection between the weak portion 12 and the protective portion 11. The weak portion 12 is configured to be destroyed along the notch 13 when the internal pressure of the battery cell is released.

[0068] In some embodiments, a notch 13 is formed between the protective portion 11 and the weak portion 12. In this case, the notch 13 is a first notch 131. The purpose of providing the first notch 131 is to allow the weak portion 12 to be broken open as the weakest position when subjected to force, so as to facilitate timely introduction of the ejecta into the exhaust channel 23.

[0069] In some embodiments, the first score 131 is a closed score or an open score. A closed score allows the weak portion 12 to be completely breached, increasing the flow rate of the ejecta and effectively reducing the impact on the temperature level of other battery cells. An open score allows the weak portion 12 to remain partially connected to the protective portion 11 after being breached, preventing the weak portion 12 from falling into the exhaust passage 23 and affecting the flow of the ejecta, and also reducing the difficulty of subsequent maintenance.

[0070] Among them, if the explosion-proof valve plate is divided into a blasting area and a non-blasting area, and the notch is used as the connection between the blasting area and the non-blasting area, a closed notch means that the notch completely separates the blasting area and the non-blasting area; a non-closed notch means that the blasting area and the non-blasting area are not completely separated, and the latter two areas are still partially connected.

[0071] refer to Figure 2 In some embodiments, a notch 13 is provided in the middle area of ​​the weak portion 12, and the weak portion 12 is configured to be destroyed along the notch 13 when the battery cell releases internal pressure; in this case, the notch 13 is a second notch 132, which facilitates the battery cell 21 to break through the weak portion 12 along the second notch 132 when releasing internal pressure, so that the ejecta can enter the exhaust channel 23 through the through hole 31, thereby preventing the negative impact of high temperature and high pressure on other battery cells.

[0072] It should be noted that since the protective part 11 and the weak part 12 are connected as one, when the weak part 12 is destroyed along the notch 13 in the middle area, the weak part 12 will not be completely washed away, but part of it will still adhere to the protective part 11. At this time, the blocking of the hole wall of the through hole 31 is still completed by the deformation part 112.

[0073] The second notch 132 is a cross (eg Figure 2As shown) or C-shaped, it should be noted that the second notch 132 can also be other polygonal shapes, such as triangle, rectangle, pentagon, etc.; for ordinary technicians in this technical field, without departing from the technical principles of the present invention, several improvements and replacements can be made, and these improvements and replacements should also be regarded as the scope of protection of the present invention.

[0074] In some embodiments, the second score 132 is a closed score or a non-closed score.

[0075] In some embodiments, the thermal runaway protection member 10 is an insulating and high-temperature resistant protection member, so that the connecting portion 111 and the deformable portion 112 of the protection portion 11 can effectively provide insulation protection around the through hole 31 of the partition component 30 .

[0076] In some embodiments, since the deformable portion 112 forms a raised periphery after deformation, to prevent the deformable portion 112 from cracking when subjected to high temperature and pressure, thereby losing its protective function against the inner wall of the through hole 31, the insulating and high-temperature-resistant protective member is preferably made of a ceramic, fiber, or silicate material, such as foam, ceramic silicone, or fiberglass. Under the disturbance of the exhaust airflow and ejected materials from the battery cell explosion valve, the deformable portion 112 will bend along the fold 113 and wrap around the wall of the through hole 31, thereby providing insulation and protection.

[0077] In some embodiments, it should be noted that both side surfaces of the partition member 30 need to be insulated to prevent the ejecta from contacting the side surfaces of the partition member 30 when erupting or rebounding, thereby preventing a more serious short circuit risk.

[0078] In some embodiments, the connecting portion 111 is connected to the partition component 30, usually in a fixed connection manner, to avoid displacement of the thermal runaway protection component 10 when the battery cell 21 erupts due to thermal runaway, to ensure that the explosion-proof valve 211 of the battery cell 21, the weak portion 12 and the through hole 31 of the partition component 30 are always in a straight line, and to ensure that the deformation portion 112 can form a circle of protruding edges covering the wall of the through hole 31 after deformation.

[0079] In some embodiments, the separator 30 is bonded to the bottom wall of the battery cell 21 with a structural adhesive (sealing layer), and the thermal runaway protection member 10 has a certain height to prevent the adhesive from flowing between the explosion-proof valve 211 and the through-hole 31 of the battery cell 21. The provision of this structural adhesive (sealing layer) not only provides a fixed connection to the battery cell 21, but also ensures a tight seal during a battery cell 21 explosion, preventing the erupted material from leaking through the connection between the battery cell 21, the protection member, and the separator 30 and entering other spaces, thereby avoiding affecting other surrounding battery cells 21 or components and reducing the risk of fire or heat spread.

[0080] In some embodiments, the deformation portion 112 extends from the edge of the through hole 31 to the middle of the through hole 31, and the length of the deformation portion 112 extending from the edge of the through hole 31 to the middle of the through hole 31 is greater than the thickness of the hole wall of the through hole 31. On the one hand, it can block the hole wall of the through hole 31 to a certain extent, and on the other hand, it can enable the deformation portion 112 to form a circle of protruding edges after deformation to cover the hole wall of the through hole 31; with this arrangement, since the explosion-proof valve 211 of the battery cell 21 corresponds to the weak portion 12, and the weak portion 12 corresponds to the through hole 31, the deformation portion 112 can be deformed toward one side of the through hole 31 when under pressure, thereby forming a circle of protruding edges that can cover the hole wall of the through hole 31, so that the partition component 30 as a whole forms an insulating effect, so as to overcome the risk of short circuit caused by the existing process that it is difficult to ensure that the hole wall portion of the through hole 31 is completely covered with the insulating layer.

[0081] Furthermore, the length L1 of the deformed portion 112 extending toward the middle of the through hole 31 and the thickness of the partition member are L2, wherein L1≥L2, and 1mm≤L1≤7mm, and / or 1mm≤L2≤7mm.

[0082] Specifically, the thickness L2 of the partition component can be within the range of 1 mm to 7 mm. If the partition component 30 is thin, the support for the structure is insufficient; if the partition component 30 is thick, it is not conducive to the overall spatial arrangement of the battery pack. The corresponding length of the deformation portion 112 protruding from the through hole 31 represents the bent part, and its length is L1 and must be greater than the thickness of the hole wall. The corresponding range of L1 can also be set to 1 mm ≤ L1 ≤ 7 mm.

[0083] In some embodiments, the partition component 30 is a liquid cooling plate, and coolant is passed through the liquid cooling plate. The battery cell 21 is connected to the liquid cooling plate. The coolant flowing through the liquid cooling plate can not only cool the battery cell 21, but also cool the ejecta entering the exhaust channel 23, thereby effectively controlling its temperature and reducing the impact on the temperature level of other battery cells.

[0084] In other embodiments, the partition component 30 may also be made of other metal materials.

[0085] In other embodiments, a protective member may be provided for each through hole 31, or a long protective member (formed by multiple protective members connected) may be provided for a row of through holes 31. With this arrangement, when one of the battery cells 21 experiences thermal runaway eruption, the protective members of other normal battery cells 21 around it can be ensured to remain intact, and the ejecta in the exhaust channel 23 can be reversely blocked from affecting other normal battery cells.

[0086] It should be noted that due to the high temperature and high pressure of the eruption material, it will splash and diffuse after entering the exhaust duct 23, reducing both its temperature and pressure. Without protective measures, other normal battery cells 21 are directly connected to the exhaust duct 23, and the eruption material may come into contact with other normal battery cells 21, causing secondary damage. This may cause other normal battery cells 21 to be affected by heat or damage the explosion-proof valve 211, thereby causing thermal runaway in other battery cells 21. Each through hole 31 is provided with a corresponding protective member, which ensures that the protective member can be opened when subjected to high-pressure eruption material. At the same time, the diffusion of the eruption material in the exhaust duct 23 will not adversely affect other normal battery cells 21, thereby improving the safety of the battery pack.

[0087] The working process of the present invention is as follows: during installation, the explosion-proof valve 211 of the battery cell 21, the weak portion 12, and the through hole 31 of the partition component 30 are always in a straight line. When the battery cell 21 experiences thermal runaway and reaches the opening threshold of the explosion-proof valve 211, the explosion-proof valve 211 explodes, and the ejected material (such as high-temperature and high-pressure gas, molten material, etc.) is ejected through the explosion-proof valve 211 to the deformed portion 112 and the weak portion 12. Under high pressure and high temperature, the weak portion 12 is opened, and the ejected material can enter the exhaust channel through the through hole 31. 23, preventing the negative influence of high temperature and high pressure on other battery cells 21; at the same time, the deformation portion 112 is deformed to form a circle of protruding edges extending into the through hole 31. Since the length of the deformation portion 112 extending from the edge of the through hole 31 to the middle of the through hole 31 is greater than the thickness of the partition component 30, the protruding edges can completely cover the hole wall of the through hole 31, so that the partition component 30 as a whole forms an insulating effect, avoiding the contact of the ejected material with the non-insulating part of the partition component 30 and causing a more serious short circuit risk.

[0088] In summary, the utility model provides a battery pack, which, by configuring the thermal runaway protection component 10 into a protection portion 11 and a weak portion 12, can destroy the weak portion 12 when thermal runaway occurs in the battery cell 21, so that the ejecta can smoothly enter the exhaust channel 23. Moreover, since the protection portion 11 includes a connecting portion 111 and a deformation portion 112, the deformation portion 112 can be deformed during thermal runaway to form a circle of protruding edges covering the hole wall of the through hole 31, thereby reducing the risk of a short circuit between the high-temperature and high-pressure ejecta and the hole wall, thereby improving the safety of the battery.

[0089] The above description is only a preferred embodiment of the present invention. It should be noted that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention. The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above preferred embodiments. The examples should be regarded as illustrative and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0090] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in the embodiments can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A battery pack, characterized in that: include: A battery pack box (20) is provided with a battery cell (21) therein, and the battery cell (21) is provided with an explosion-proof valve (211); a partition component (30), the partition component (30) being arranged inside the battery pack case (20) and dividing the interior of the battery pack case into a battery cavity (22) and an exhaust passage (23), the partition component (30) being provided with a through hole (31) communicating the battery cavity and the exhaust passage, the battery cell (21) being arranged in the battery cavity (22); and a thermal runaway protection member (10) disposed on a side of the partition member (30) close to the battery chamber (22) and covering the through hole (31); the thermal runaway protection member (10) comprises a protection portion (11) and a weak portion (12); the weak portion (12) is disposed corresponding to the explosion-proof valve (211); The protective portion (11) comprises a connecting portion (111) and a deformable portion (112), wherein the deformable portion (112) is connected to the outer periphery of the weak portion (12); the connecting portion (111) is connected to the outer periphery of the deformable portion (112), and a side of the connecting portion (111) away from the deformable portion (112) is connected to the partition component (30); When the battery cell (21) releases internal pressure, the ejected material of the battery cell can be discharged into the exhaust channel (23) through the explosion-proof valve, the weak portion (12) and the through hole (31), and the deformable portion (112) is deformed to cover the hole wall of the through hole (31).

2. A battery pack according to claim 1, characterized in that: The orthographic projection of the weak portion (12) on the partition component (30) is located within the corresponding through hole (31).

3. The battery pack according to claim 2, characterized in that: Along the thickness direction of the partition component (30), the weak portion (12) and the explosion-proof valve (211) have orthographic projections on the partition component (30), and the orthographic projection of the weak portion (12) is located within the orthographic projection of the explosion-proof valve (211).

4. The battery pack according to claim 2, characterized in that: The orthographic projection of the deformation portion (112) on the partition component (30) along the thickness direction of the partition component (30) falls into the through hole (31).

5. The battery pack according to claim 4, characterized in that: Along the thickness direction of the partition component (30), the deformation portion (112) and the explosion-proof valve (211) have an orthographic projection on the partition component (30), the orthographic projection of the deformation portion (112) is annular, and the inner periphery of the orthographic projection of the deformation portion is located within the orthographic projection of the partition component; in the radial direction of the through hole (31), the distance between the inner periphery of the orthographic projection of the deformation portion (112) and the outer periphery of the orthographic projection of the explosion-proof valve (211) is D1, and 0.5 mm ≤ D1 ≤ 3 mm.

6. The battery pack according to claim 4, characterized in that: In the radial direction of the through hole (31), the length of the deformable portion (112) extending toward the middle of the through hole (31) is equal to or greater than the thickness of the hole wall of the through hole (31), so that the deformable portion (112) can completely cover the hole wall of the through hole (31) after deformation.

7. The battery pack according to claim 6, characterized in that: In the radial direction of the through hole (31), the length L1 of the deformation portion (112) extending toward the middle of the through hole (31) is 1 mm ≤ L1 ≤ 7 mm; and / or The thickness of the partition component (30) is L2, and 1mm≤L2≤7mm.

8. The battery pack according to claim 1, characterized in that: The orthographic projection area of ​​the deformation portion in the through hole (31) is larger than the area of ​​the hole wall of the through hole (31).

9. The battery pack according to claim 1, characterized in that: The protective portion (11) and the weak portion (12) are integrally formed, a notch (13) is provided at the connection between the weak portion (12) and the protective portion (11), and the weak portion (12) is configured to be destroyed along the notch (13) when the internal pressure of the battery cell is released.

10. The battery pack according to claim 1, characterized in that: A notch (13) is provided in the middle area of ​​the weak portion (12), and the weak portion (12) is configured to be destroyed along the notch (13) when the internal pressure of the battery cell is released.

11. The battery pack according to claim 10, characterized in that: The notch (13) is a closed notch or a non-closed notch.

12. The battery pack according to claim 1, characterized in that: A fold (113) is provided at the junction of the connecting portion (111) and the deforming portion (112), and the deforming portion (112) is deformed along the fold (113).

13. The battery pack according to claim 12, characterized in that: In the direction of the thermal runaway protection element (10) being projected onto the partition component (30), the projection of the fold (113) coincides with the edge of the through hole (31).

14. The battery pack according to claim 13, characterized in that: The through hole (31) is a polygonal hole, and the fold (113) includes multiple straight line marks.

15. A battery pack according to any one of claims 12 to 14, characterized in that: The fold (113) is provided on a side of the thermal runaway protection element (10) facing the through hole (31), and the thickness of the fold (113) is thinner than the deformation portion (112) and / or the connection portion (111).

16. The battery pack according to claim 1, characterized in that: The thermal runaway protection element (10) is an insulating and high-temperature resistant protection element.

17. The battery pack according to claim 16, characterized in that: The insulating high-temperature resistant protective member is a ceramic material protective member, a fiber material protective member or a silicate material protective member.

18. The battery pack according to claim 1, characterized in that: The partition component (30) is a liquid cooling plate.

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