Battery pack

Abstract

The present application relates to the technical field of batteries, and specifically discloses a battery pack, comprising a battery pack case, a separation component for separating an inner space of the battery pack into a battery cavity and an exhaust channel, and a thermal runaway protection member. A through hole that communicates the battery cavity with the exhaust channel is formed in the separation component, and the thermal runaway protection member covers the through hole and comprises a protection portion and a weakened portion. The protection portion comprises a connection portion used for connecting to the separation component and a deformable portion connected to the inner periphery of the connection portion. When a battery cell releases internal pressure, the deformable portion can deform to cover the hole wall of the through hole, thereby reducing the risk of a conductive short circuit formed between high-temperature and high-pressure ejecta and the hole wall, and thus improving the safety of the battery.

Description

Battery pack TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery pack. BACKGROUND

[0002] The existing battery pack usually includes a plurality of battery monomers, and an explosion-proof valve is arranged on each battery monomer. When the battery monomer is in a thermal runaway state such as overcharge, short circuit or overheating, the pressure inside the battery monomer increases. When the opening threshold of the explosion-proof valve is reached, the explosion-proof valve is opened to ensure that the spewing material (such as high-temperature and high-pressure gas, molten material, etc.) is smoothly discharged, thereby avoiding explosion due to excessive pressure inside the battery monomer.

[0003] In addition, if the spewing material flows among other battery monomers, its high-temperature and high-pressure characteristics will affect the stability of other battery monomers, and even cause a serious safety problem of heat spread. Therefore, in the prior art, an exhaust passage is designed to disperse the spewing material and prevent the negative effects of high temperature and high pressure on other battery monomers. In the prior art, a separation component is arranged to separate the exhaust area and the space where the battery monomers (battery cells) are installed, so that the spewing material can enter the exhaust passage through the separation component when the explosion-proof valve of the battery monomer is opened.

[0004] However, since the spewing material has electrical conductivity, it is easy to cause a short circuit problem in the battery pack after contacting other charged objects, thereby causing a more serious thermal runaway chain reaction. Therefore, when the separation component is a metal part, insulation treatment is also performed on both sides of the separation component, but the existing process cannot completely cover the hole wall part of the exhaust through hole with an insulation layer, and there is still a risk of short circuit. SUMMARY

[0005] The technical problem to be solved by the present application is how to solve the problem of short circuit risk of the metal separation component in the prior art due to the fact that the hole wall part of the exhaust through hole of the metal separation component cannot be completely insulated.

[0006] To solve the above technical problems, the present application provides a battery pack, comprising:

[0007] a battery pack box body, an inside of which is provided with a battery monomer, and the battery monomer is provided with an explosion-proof valve;

[0008] a separation component, which is arranged in the inside of the battery pack box body and separates the inside of the battery pack box body into a battery cavity and an exhaust passage, and the separation component is provided with a through hole communicating the battery cavity and the exhaust passage, and the battery monomer is arranged in the battery cavity; and

[0009] A thermal runaway protection member is arranged on the side of the partition component close to the battery cavity and covers the through hole, the thermal runaway protection member comprises a protection part and a weak part, and the weak part is arranged corresponding to the explosion-proof valve;

[0010] The protection part comprises a connecting part and a deformation part, the deformation part is connected to the outer periphery of the weak part, the connecting part connects the outer periphery of the deformation part, and the connecting part is connected to the partition component, and the side of the connecting part away from the deformation part is connected to the partition component;

[0011] When the battery monomer discharges the internal pressure, the eruption of the battery monomer can be discharged into the exhaust passage through the explosion-proof valve, the weak part and the through hole, and the deformation part is deformed to cover the hole wall of the through hole.

[0012] In some embodiments, the "cover" means that the through hole is covered or / and blocked by the thermal runaway protection member.

[0013] Further preferably, the weak part has a projection on the partition component in the thickness direction of the partition component, and the projection of the weak part is located in the projection of the explosion-proof valve.

[0014] Further preferably, the weak part and the explosion-proof valve have projections on the partition component in the thickness direction of the partition component, and the projection of the weak part is located in the projection of the explosion-proof valve.

[0015] Further preferably, the projection of the deformation part on the partition component in the thickness direction of the partition component falls into the through hole.

[0016] Further preferably, the deformation part and the explosion-proof valve have projections on the partition component in the thickness direction of the partition component, the projection of the deformation part is annular, and in the radial direction of the through hole, the distance between the inner periphery of the projection of the deformation part and the outer periphery of the projection of the explosion-proof valve is D1, and 0.5mm≤D1≤3mm.

[0017] Further preferably, in the radial direction of the through hole, the length of the deformation part extending to 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 part can completely cover the hole wall of the through hole after deformation.

[0018] Further preferably, in the radial direction of the through hole, the length L1 of the deformation part extending to the middle of the through hole is 1mm≤L1≤7mm.

[0019] And / or

[0020] The thickness of the partition component is L2, and 1mm≤L2≤7mm.

[0021] Further preferably, the area of the orthographic projection of the deformation portion in the through hole is greater than the area of the hole wall of the through hole.

[0022] Further preferably, the protective portion and the weak portion are integrally formed, and the weak portion is provided with a notch at the connection with the protective portion, and the weak portion is configured to be broken along the notch when the battery cell releases internal pressure.

[0023] Further preferably, the middle region of the weak portion is provided with a notch, and the weak portion is configured to be broken along the notch when the battery cell releases internal pressure.

[0024] Further preferably, the notch is a closed notch or an open notch.

[0025] Further preferably, a fold is arranged at the junction of the connection portion and the deformation portion, and the deformation portion deforms along the fold.

[0026] Further preferably, in the direction of the orthographic projection of the thermal runaway protection piece on the separation component, the projection of the fold coincides with the edge of the through hole.

[0027] Further preferably, the through hole is a polygonal hole, and the fold includes multiple straight notches.

[0028] Further preferably, the fold is arranged on the side of the thermal runaway protection piece facing the through hole, and the thickness of the fold is thinner than the deformation portion and / or the connection portion.

[0029] Further preferably, the thermal runaway protection piece is an insulating high-temperature-resistant protection piece.

[0030] Further preferably, the insulating high-temperature-resistant protection piece is a ceramic material protection piece, a fiber material protection piece, or a silicate material protection piece.

[0031] Further preferably, the separation component is a liquid cooling plate.

[0032] Compared with the prior art, the battery pack provided in the application has the following beneficial effects:

[0033] The application provides a battery pack. The separation component separates the battery pack into a battery cavity and an exhaust passage, and a through hole is arranged on the separation component to communicate the battery cavity and the exhaust passage. A thermal runaway protection piece is arranged to cover the through hole, and the thermal runaway protection piece is arranged as a protective portion and a weak portion. When the battery cell experiences thermal runaway, the weak portion is broken, so that the spewing material can smoothly enter the exhaust passage. Since the protective portion includes a connection portion and a deformation portion, the deformation portion can cover the hole wall of the through hole when thermal runaway occurs, thereby reducing the risk of conduction short circuit between the high-temperature high-pressure spewing material and the hole wall, and improving the safety of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0034] Fig. 1 is a structural schematic diagram of the thermal runaway protection device of the present application.

[0035] Fig. 2 is a structural schematic diagram of the second score of the present application.

[0036] Fig. 3 is a structural schematic diagram of the thermal runaway protection device and the partition component of the present application.

[0037] Fig. 4 is an enlarged schematic diagram of A in Fig. 3 of the present application.

[0038] Fig. 5 is a structural schematic diagram of the battery pack of the present application.

[0039] Fig. 6 is a partial cross-sectional view of the battery pack of the present application.

[0040] Fig. 7 is an assembly view of the battery cell, the partition component and the thermal runaway protection device of the present application.

[0041] In the drawings: 10, thermal runaway protection device; 11, protection part; 111, connecting part; 112, deformation part; 113, fold; 12, weak part; 13, score; 131, first score; 132, second score; 20, battery pack box; 21, battery cell; 211, explosion-proof valve; 22, battery cavity; 23, exhaust passage; 30, partition component; 31, through hole. DETAILED DESCRIPTION

[0042] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0043] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like in the present application are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0044] The terms "first", "second", etc. are used only for the purpose of description and do not indicate or imply relative importance or a specific number of features. Thus, features defined with "first", "second" can include at least one of the features explicitly or implicitly. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly and specifically limited.

[0045] In addition, unless explicitly and specifically defined otherwise, the terms "mount", "connected", "connection" should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through intermediate medium, can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0046] In the present application, unless explicitly and specifically defined otherwise, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the first feature is higher in horizontal height than the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the first feature is lower in horizontal height than the second feature.

[0047] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can be a middle element. When an element is referred to as "connected" to another element, it can be directly connected to the other element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for the purpose of description only and are not the only implementation.

[0048] As shown in FIGS. 1-7, the present embodiment provides a battery pack, which includes a battery pack case 20, a partition member 30, and a thermal runaway protection member 10.

[0049] In some embodiments, the battery pack box 20 is internally provided with battery monomers 21, and the battery monomers 21 are provided with explosion-proof valves 211; the battery pack box 20 is usually a box structure enclosed by an upper cover, a bottom plate and a frame, and the inside of the battery pack box 20 is provided with a partition component 30, which divides the inside of the battery pack box 20 into a battery cavity 22 and an exhaust passage 23; the battery cavity 22 is used for placing the battery monomers 21, and the exhaust passage 23 is used for timely dispersing the spewing matter of the battery monomers 21 when the battery monomers 21 occur thermal runaway, so as to avoid causing more serious thermal runaway chain reaction.

[0050] In some embodiments, the partition component 30 is provided with a through hole 31 communicating the battery cavity 22 and the exhaust passage 23, and the thermal runaway protection piece 10 is placed in the battery cavity 22 and connected with the partition component 30, and the thermal runaway protection piece 10 is used for covering the through hole 31 when the battery monomers 21 spew.

[0051] In some embodiments, the thermal runaway protection piece 10 includes a protection part 11 and a weak part 12, the protection part 11 is formed around the weak part 12, and the weak part 12 is configured to be damaged when the battery monomers 21 release internal pressure. The weak part 12 can be more easily broken or ruptured to form a gap when the battery monomers 21 spew, so that the spewing matter can smoothly pass through the gap into the exhaust passage 23, avoiding the situation that the protection piece cannot be broken when the pressure relief valve should be broken; the protection part 11 is used for connecting the weak part 12 and the partition component 30, and can prevent the spewing matter from escaping from the gap between the battery monomers 21 and the partition component 30 to affect other normal battery monomers 21.

[0052] The protection part 11 includes a connecting part 111 and a deformation part 112, wherein the deformation part 112 is connected to the outer periphery of the weak part 12; the connecting part 111 is connected to the outer periphery of the deformation part 112, and the side of the connecting part 111 away from the deformation part 112 is connected with the partition component 30.

[0053] Specifically, the weak part 12 is provided corresponding to the through hole 31, and the explosion-proof valve 211 of the battery monomer 21 corresponds to the weak part 12; when the battery monomers 21 release internal pressure, the weak part 12 can allow the spewing matter of the battery monomers 21 to pass through and be discharged from the through hole 31 to the exhaust passage 23, and the deformation part 112 can be deformed to at least partially cover the hole wall of the through hole 31.

[0054] Wherein, the deformation part 112 is deformed to cover the hole wall of the through hole 31, which means that in the radial direction extending along the axial hole wall of the through hole 31, the deformation part 112 can block the hole wall, which includes that the deformation part 112 completely adheres to the hole wall, or the deformation part 112 is bent but has a gap with the hole wall, etc.

[0055] The application provides a battery pack, which is internally divided into a battery cavity 22 and an exhaust passage 23 by a partition component 30, and a through hole 31 is arranged on the partition component 30 to communicate the battery cavity 22 and the exhaust passage 23, a thermal runaway protection piece 10 is arranged to cover the through hole 31, and the thermal runaway protection piece 31 is arranged as a protection part 11 and a weak part 12, when the battery monomer 21 appears thermal runaway, the weak part 12 is damaged, so that the eruption material can smoothly enter the exhaust passage 23, and because the protection part 11 comprises a connecting part 111 and a deformation part 112, the deformation part 112 can cover the hole wall of the through hole 31 when thermal runaway occurs, so as to reduce the risk of forming a conduction short circuit between the high-temperature and high-pressure eruption material and the hole wall, thereby improving the safety of the battery.

[0056] In some embodiments, the weak part 12 is projected on the partition component 30, and the explosion-proof valve 211 of the battery monomer 21 is projected on the partition component 30, and the projection of the weak part 12 is located in the projection of the explosion-proof valve 211; in this way, when the weak part 12 is damaged when the battery monomer releases internal pressure, the eruption material of the battery monomer 21 can be timely dispersed into the exhaust passage 23 through the through hole 31, thereby avoiding more serious thermal runaway chain reaction.

[0057] Further, in the thickness direction of the partition component 30, the weak part 12 and the explosion-proof valve 211 have projections on the partition component 30, and the projection of the weak part 12 is located in the projection of the explosion-proof valve 211. Specifically, the projection area of the weak part 12 is smaller than the area of the explosion-proof valve 211 and has a corresponding relationship, which can ensure that when the explosion-proof valve 211 is actuated, the weak part 12 will be impacted and broken, and can be broken smoothly.

[0058] In some embodiments, the protection part 11 comprises a connecting part 111 for connecting with the partition component 30 and a deformation part 112 connected to the inner periphery of the connecting part 111, wherein the weak part 12 is connected to the inner periphery of the deformation part 112 for corresponding with the explosion-proof valve 211 of the battery monomer 21, and when the battery monomer 21 releases internal pressure, the weak part 12 can be damaged to discharge the eruption material of the battery monomer 21 from the through hole; in addition, the deformation part 112 is a closed loop structure, and the deformation part 112 protrudes from the through hole in the radial direction of the through hole to form a protruding periphery, and the deformation part 112 is configured to be deformed towards the direction of the through hole when the explosion-proof valve 211 erupts, and can cover the hole wall of the through hole. Because the protection part 11 comprises the connecting part 111 and the deformation part 112, the deformation part 112 can be deformed to form a protruding periphery for completely covering the hole wall of the through hole 31 when thermal runaway occurs, thereby reducing the risk of forming a conduction short circuit between the high-temperature and high-pressure eruption material and the hole wall, and further improving the safety of the battery.

[0059] Specifically, the deformation part 112 and the explosion-proof valve 211 have orthographic projections on the partition member 30, and the orthographic projection of the deformation part 112 falls within the orthographic projection of the explosion-proof valve 211. In the radial direction of the through hole 31, the distance between the orthographic projection inner periphery of the deformation part 112 and the orthographic projection outer periphery of the explosion-proof valve 211 is D1 (as shown in FIG. 7), and D1 satisfies 0.5mm≤D1≤3mm.

[0060] Illustratively, D1 can be 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 2mm, 2.5mm, 3mm. The distance D1 represents the radial distance of the deformation part 112 protruding from the explosion-proof valve 211. If the distance is too small, the deformation part will not be effectively impacted when the explosion-proof valve 211 sprays, causing the deformation part to deform insufficiently; and if the distance is too large, it may block the spray, causing the battery monomer thermal runaway exhaust to be not smooth.

[0061] In some embodiments, a crease 113 is arranged at the junction of the connecting part 111 and the deformation part 112, so that the deformation part 112 can bend along the crease 113 under the disturbance of the gas flow and the spray of the battery cell explosion valve. The material of the deformation part 112 can be elastic, and the deformation part 112 automatically rebounds to the initial state after the spray is finished; or the material of the deformation part 112 can be hard, and the deformation part 112 still remains in the bent state after the spray is finished.

[0062] In some embodiments, when the battery monomer 21 is in thermal runaway, in order to further improve the effect of the deformation of the deformation part 112, the projection of the crease 113 coincides with the edge of the through hole 31 in the direction of the orthographic projection of the thermal runaway protection piece 10 on the partition member 30, so that the deformation part 112 can quickly deform to form a protruding periphery after being pressed to completely cover the hole wall of the through hole 31.

[0063] In some embodiments, the through hole 31 can be a circular hole, an elliptical hole or a polygonal hole. When the through hole 31 is a circular hole, the crease 113 is a circular crease; when the through hole 31 is an elliptical hole, the crease 113 is a corresponding elliptical crease; and when the through hole 31 is a polygonal hole, the crease 113 includes multiple straight creases.

[0064] In some embodiments, the crease 113 is formed by reducing the thickness of the thermal runaway protection piece 10 towards the side of the through hole 31, so that the deformation part 112 can quickly deform to cover the hole wall of the through hole 31 after being pressed, thereby reducing the risk of conduction short circuit between the high-temperature and high-pressure spray and the hole wall, and further improving the safety of the battery.

[0065] In some embodiments, referring to FIG. 1, the protective part 11 and the weak part 12 are integrally formed into a sheet structure, and the weak part 12 is provided with a notch 13 at the connection with the protective part 11, and the weak part 12 is configured to be broken along the notch 13 when the battery cell releases internal pressure.

[0066] In some embodiments, a notch 13 is formed between the protective part 11 and the weak part 12, and at this time, the notch 13 is a first notch 131, and the first notch 131 is provided to make the weak part 12 be broken as the weakest position when stressed, so as to timely guide the eruption material into the exhaust passage 23.

[0067] In some embodiments, the first notch 131 is a closed notch or an open notch. The closed notch can make the weak part be completely broken, improve the flow speed of the eruption material, and effectively reduce the temperature level impact on other battery cells; the open notch can make the weak part 12 still be connected to the protective part 11 after being broken, so as to avoid the weak part 12 from falling into the exhaust passage 23 and affecting the flow of the eruption material, and also reduce the difficulty of later maintenance.

[0068] In some embodiments, the closed notch means that the notch completely isolates the explosion area and the non-explosion area, and the open notch means that the explosion area and the non-explosion area are not completely isolated, and the two areas are still partially connected.

[0069] Referring to FIG. 2, in some embodiments, the middle region of the weak part 12 is provided with a notch 13, and the weak part 12 is configured to be broken along the notch 13 when the battery cell releases internal pressure; at this time, the notch 13 is a second notch 132, which facilitates the battery cell 21 to break the weak part 12 along the second notch 132 when releasing internal pressure, so that the eruption material can enter the exhaust passage 23 through the through hole 31, and prevent the negative impact of high temperature and high pressure on other battery cells.

[0070] It should be noted that, since the protective part 11 and the weak part 12 are connected as a whole, when the weak part 12 is broken along the notch 13 in the middle region, the weak part 12 will not be completely broken, but part of it will still be attached to the protective part 11, and at this time, the hole wall of the through hole 31 is still blocked by the deformed part 112.

[0071] The second notch 132 is in the shape of a cross (as shown in FIG. 2) or a C letter, and it should be noted that the second notch 132 can also be other polygonal shapes, such as a triangle, a rectangle, a pentagon, etc.; for those skilled in the art, without departing from the technical principles of the present application, a number of improvements and replacements can be made, and these improvements and replacements should also be considered as the protection scope of the present application.

[0072] In some embodiments, the second score line 132 is a closed score line or an open score line.

[0073] In some embodiments, the thermal runaway protection piece 10 is an insulating high-temperature-resistant protection piece, so that the connecting part 111 and the deformed part 112 of the protection part 11 can effectively play an insulating protection effect on the surrounding of the through hole 31 of the partition component 30.

[0074] In some embodiments, since the deformed part 112 forms a protruding peripheral edge after deformation, in order to avoid the deformed part 112 from cracking under high temperature and high pressure and losing the protection effect on the inner wall of the through hole 31, the insulating high-temperature-resistant protection piece is preferably a protection piece made of ceramic material, fiber material or silicate material, such as foam, ceramic silica gel, glass fiber, etc. Under the disturbance of the gas stream and the eruption of the battery cell explosion valve, the deformed part 112 will be bent along the score line 113 and cover the hole wall of the through hole 31, thereby forming an insulating protection effect.

[0075] In some embodiments, it should be noted that the two side surfaces of the partition component 30 need to be insulated to avoid the contact between the eruption or rebound of the eruption material and the two side surfaces of the partition component 30, which may cause more serious short circuit risk.

[0076] In some embodiments, the connecting part 111 is connected with the partition component 30, usually in a fixed connection manner, to avoid the displacement of the thermal runaway protection piece 10 when the battery cell 21 is in thermal runaway and eruption, and to ensure that the explosion valve 211 of the battery cell 21, the weak part 12 and the through hole 31 of the partition component 30 are always in a straight line, and to ensure that the deformed part 112 can form a protruding peripheral edge covering the hole wall of the through hole 31 after deformation.

[0077] In some embodiments, the partition component 30 is bonded with the bottom wall of the battery cell 21 by using a structural adhesive (sealing layer), and the thermal runaway protection piece 10 has a certain height, which can prevent the adhesive from flowing between the explosion valve 211 of the battery cell 21 and the through hole 31. The structural adhesive (sealing layer) provides a fixed connection effect on the battery cell 21, and also ensures the sealing property when the battery cell 21 erupts, prevents the eruption material from leaking through the connection between the battery cell 21 and the protection component and the partition component 30 to enter other spaces, avoids affecting other battery cells 21 or elements around, and reduces the occurrence of fire burning or heat spreading.

[0078] 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, the deformation portion 112 can shield the hole wall of the through hole 31 to some extent, and on the other hand, the deformation portion 112 can form a protruding peripheral edge after deformation to cover the hole wall of the through hole 31. With such an arrangement, since the explosion-proof valve 211 of the battery monomer 21 corresponds to the weak portion 12, and the weak portion 12 corresponds to the through hole 31, the deformation portion 112 can deform to one side of the through hole 31 when pressed, thereby forming a protruding peripheral edge to cover the hole wall of the through hole 31, so that the whole separation component 30 forms an insulating effect, thereby overcoming the risk of short circuit caused by the difficulty of the existing process in ensuring that the hole wall part of the through hole 31 is completely covered by the insulating layer.

[0079] Further, as shown in FIG. 7, the length L1 of the deformation portion 112 extending to the middle of the through hole 31, the thickness of the separation component is L2, wherein L1≥L2, and 1mm≤L1≤7mm, and / or 1mm≤L2≤7mm.

[0080] Specifically, the thickness L2 of the separation component can be 1mm to 7mm. If the separation component 30 is too thin, the support of the structure is insufficient; if the separation component 30 is too thick, it is not conducive to the space arrangement of the whole battery pack, and the corresponding deformation portion 112 protrudes from the through hole 31. The length of the bent part is L1 and is greater than the thickness of the hole wall. The range of L1 can also be set to 1mm≤L1≤7mm.

[0081] In some embodiments, the separation component 30 is a liquid cooling plate, and a cooling liquid is introduced into the liquid cooling plate. The battery monomer 21 is connected to the liquid cooling plate, and the cooling liquid flowing in the liquid cooling plate not only cools the battery monomer 21, but also cools and cools the eruption material entering the exhaust passage 23. It can effectively control the temperature to reduce the temperature influence on other battery monomers.

[0082] In other embodiments, the separation component 30 can also be made of other metal materials.

[0083] In other embodiments, the protection piece can be one through hole 31 corresponding to one, or one row of through holes 31 setting a long protection piece (formed by connecting multiple protection pieces). With such an arrangement, when one of the battery monomers 21 appears thermal runaway and eruption, it can ensure that the protection pieces of the surrounding other normal battery monomers 21 remain intact, and can block the influence of the ejected material in the exhaust passage 23 on other normal battery monomers.

[0084] It should be noted that due to the high temperature and high pressure characteristics of the spewing material, the spewing material will splash and diffuse after entering the exhaust passage 23, and its temperature and pressure will decrease. If there is no protective measure and the other normal battery monomers 21 are directly connected with the exhaust passage 23, the spewing material may contact the other normal battery monomers 21, causing secondary damage, leading to the other normal battery monomers 21 being heat affected or the explosion-proof valve 211 being damaged, thereby causing the other battery monomers 21 to also spew heat out of control. One through hole 31 is provided with one protective piece, which can be punched open when bearing high-pressure spewing material, and at the same time will not be affected by the spewing material in the exhaust passage 23 in the reverse direction. Other normal battery monomers 21, thereby improving the safety of the battery pack.

[0085] The working process of the present application is: during installation, the explosion-proof valve 211 of the battery monomer 21, the weak part 12 and the through hole 31 of the partition component 30 are always on a straight line. When the battery monomer 21 appears heat runaway and reaches the opening threshold of the explosion-proof valve 211, the explosion-proof valve 211 is blown open, and the spewing material (such as high-temperature and high-pressure gas, molten material, etc.) is spewed to the deformation part 112 and the weak part 12. Under high pressure and high temperature, the weak part 12 is punched open, and the spewing material can enter the exhaust passage 23 through the through hole 31, preventing the negative effects of high temperature and high pressure on other battery monomers 21; at the same time, the deformation part 112 is deformed to form a protruding peripheral edge extending into the through hole 31. Since the length of the deformation part 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 peripheral edge 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 spewing material contacting the non-insulating part of the partition component 30 to cause more serious short circuit risk.

[0086] In summary, the battery pack provided by the present application sets the heat runaway protection piece 10 as a protection part 11 and a weak part 12, which can damage the weak part 12 when the battery monomer 21 appears heat runaway, so that the spewing material can smoothly enter the exhaust passage 23. Since the protection part 11 includes a connecting part 111 and a deformation part 112, the deformation part 112 can be deformed to form a protruding peripheral edge covering the hole wall of the through hole 31 when heat runaway occurs, thereby reducing the risk of high-temperature and high-pressure spewing material forming a conductive short circuit with the hole wall, and further improving the safety of the battery.

[0087] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and replacements can be made without departing from the technical principles of the present application, and these improvements and replacements should also be considered as the protection scope of the present application. The basic principles, main features and advantages of the present application are shown and described above, and it is obvious for those skilled in the art that the present application is not limited to the details of the preferred embodiments, and the embodiments should be considered as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims should be included in the present application.

[0088] In addition, it should be understood that, although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description manner of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in the embodiments can also be properly combined to form other embodiments which can be understood by those skilled in the art.

Claims

1. A battery pack, comprising: a battery pack case (20) having a battery cell (21) with an explosion-proof valve (211) inside; a partition component (30) arranged inside the battery pack case (20) and partitioning the battery pack case (20) 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 (22) and the exhaust passage (23), and the battery cell (21) being arranged in the battery cavity (22); and a thermal runaway protection member (10) arranged on a side of the partition component (30) close to the battery cavity (22) and covering the through hole (31), the thermal runaway protection member (10) comprising a protection portion (11) and a weak portion (12), and the weak portion (12) being arranged corresponding to the explosion-proof valve (211); the protection portion (11) comprising a connecting portion (111) and a deformation portion (112), the deformation portion (112) being connected to the outer periphery of the weak portion (12), and the connecting portion (111) being connected to the outer periphery of the deformation portion (112) and being connected to the partition component (30) on a side away from the deformation portion (112); wherein when the battery cell (21) releases internal pressure, the spewing material of the battery cell (21) can be discharged into the exhaust passage (23) through the explosion-proof valve (211), the weak portion (12) and the through hole (31), and the deformation portion (112) is deformed to cover the hole wall of the through hole (31). 2.The battery pack of claim 1, wherein the weak portion (12) has a projection on the partition component (30) located in the corresponding through hole (31). 3.The battery pack of claim 2, wherein along the thickness direction of the partition component (30), the weak portion (12) and the explosion-proof valve (211) have projections on the partition component (30), and the projection of the weak portion (12) is located in the projection of the explosion-proof valve (211). 4.The battery pack of claim 2, wherein the projection of the deformation portion (112) on the partition component (30) along the thickness direction of the partition component (30) falls in the through hole (31). 5.The battery pack of claim 4, wherein along the thickness direction of the partition component (30), the deformation portion (112) and the explosion-proof valve (211) have projections on the partition component (30), the projection of the deformation portion (112) is annular, and the inner periphery of the projection of the deformation portion (112) is located in the projection of the partition component (30); and in the radial direction of the through hole (31), the distance between the inner periphery of the projection of the deformation portion (112) and the outer periphery of the projection of the explosion-proof valve (211) is D1, and 0.5mm≤D1≤3mm. ​ ​ ​ ​ ​ 6. The battery pack according to claim 4, wherein the length of the deformation portion (112) extending into the middle of the through hole (31) in the radial direction 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 deformation portion (112) can completely cover the hole wall of the through hole (31) after deformation.

7. The battery pack according to claim 6, wherein the length L1 of the deformation portion (112) extending into the middle of the through hole (31) in the radial direction of the through hole (31) is 1 mm≤L1≤7 mm. and / or The thickness of the separation component (30) is L2, and 1 mm≤L2≤7 mm.

8. The battery pack according to claim 1, wherein the area of the orthographic projection of the deformation portion (112) in the through hole (31) is greater than the area of the hole wall of the through hole (31).

9. The battery pack according to claim 1, wherein the protective portion (11) and the weakened portion (12) are integrally formed, and the weakened portion (12) is provided with a notch (13) at the connection with the protective portion (11), and the weakened portion (12) is configured to be broken along the notch (13) when the battery cell (21) releases internal pressure.

10. The battery pack according to claim 1, wherein the middle region of the weakened portion (12) is provided with a notch (13), and the weakened portion (12) is configured to be broken along the notch (13) when the battery cell (21) releases internal pressure.

11. The battery pack according to claim 10, wherein the notch (13) is a closed notch or an open notch.

12. The battery pack according to claim 1, wherein a fold (113) is provided at the junction of the connection portion (111) and the deformation portion (112), and the deformation portion (112) is deformed along the fold (113).

13. The battery pack according to claim 12, wherein in the direction of the orthographic projection of the thermal runaway protection member (10) on the separation 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, wherein the through hole (31) is a polygonal hole, and the fold (113) comprises multiple straight line notches.

15. The battery pack according to any one of claims 12-14, wherein the fold (113) is provided on the side of the thermal runaway protection member (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, wherein the thermal runaway protection member (10) is an insulating high-temperature-resistant protection member.

17. The battery pack according to claim 16, wherein the insulating high-temperature-resistant protection member is a ceramic material protection member, a fiber material protection member, or a silicate material protection member.

18. The battery pack according to claim 1, wherein the separation component (30) is a liquid cooling plate.

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