Heat absorbing structure, battery pack and electrical equipment

Abstract

The present application provides a heat absorption structure, a battery pack and an electric device, wherein the heat absorption structure comprises: a package, the package comprises a buffer zone and at least one heat absorption zone, the package further comprises an outer edge seal and an inner edge seal, the outer edge of the package is surrounded by an outer edge seal, the inner edge seal is located between the buffer zone and the heat absorption zone, and the strength of the inner edge seal is less than the strength of the outer edge seal; a phase change heat absorption element, the phase change heat absorption element is arranged in the heat absorption zone, and the phase change heat absorption element is used to absorb heat. The heat absorption structure provided by the present application has a good effect of suppressing heat diffusion when the battery cell is under thermal runaway.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a heat absorption structure, a battery pack and an electrical device. Background Art

[0002] Multiple battery cells can be assembled to form a battery pack, and multiple battery packs can be further assembled to form a battery pack, which can provide power for electrical equipment such as vehicles.

[0003] In the related art, multiple battery cells are arranged in the same direction. Since the battery cells will generate a large amount of heat when they have thermal runaway, in order to solve the problem that the heat of one battery cell is transferred to another adjacent battery cell and cause fire in the entire battery pack, aerogel and other insulating materials are generally set between two adjacent battery cells to suppress the transfer of heat through aerogel. However, the setting of aerogel still cannot effectively suppress the large amount of heat released by the battery cell to the adjacent battery cell when it has thermal runaway, and there is still a risk that one battery cell will have thermal runaway, causing thermal runaway of the entire battery pack. Summary of the invention

[0004] Based on this, the present application provides a heat absorption structure, a battery pack and an electrical device to solve the deficiencies in the related art.

[0005] In a first aspect, the present application provides a heat absorption structure, comprising: a package, the package comprising a buffer zone and at least one heat absorption zone, the package further comprising an outer edge seal and an inner edge seal, the outer edge of the package is surrounded by an outer edge seal, the inner edge seal is located between the buffer zone and the heat absorption zone, and the strength of the inner edge seal is less than the strength of the outer edge seal;

[0006] A phase-change heat absorbing element is arranged in the heat absorbing zone and is used for absorbing heat.

[0007] In a possible implementation, the outer edge seal includes a first edge seal and a second edge seal, and the strength a1 of the first edge seal, the strength a2 of the inner edge seal, and the strength a3 of the second edge seal satisfy: a2 <a3<a1。

[0008] In a possible implementation manner, the ratio of the strength of the first edge seal to the strength of the inner edge seal satisfies: a1 / a2≥2.

[0009] In a possible implementation, the second edge seal is located at at least one outer edge of the buffer zone.

[0010] In a possible implementation, a partial area of ​​the first edge seal extends to the outer edge of the buffer zone.

[0011] In a possible implementation manner, the buffer zone is disposed on the outer periphery of the heat absorption zone.

[0012] In a possible implementation, there are two heat absorption zones, the two heat absorption zones are arranged along the first direction, and at least a portion of the buffer zone is located between the two heat absorption zones.

[0013] In a possible implementation manner, in the first direction, the length L1 of the package and the length L2 of the buffer zone satisfy: L1 / 20≤L2≤L1 / 3.

[0014] In a possible implementation manner, the ratio of the thickness of the buffer zone to the thickness of the heat absorption zone is less than or equal to 0.1.

[0015] In a possible implementation, when the buffer zone and the heat absorption zone are arranged along the first direction, in the first direction, the length L2 of the buffer zone and the length L3 of the second edge sealing satisfy: 0.1≤L3 / L2≤1.

[0016] In a possible implementation manner, a projection shape of the second edge sealing in the thickness direction of the package includes a quadrilateral and / or a triangle.

[0017] In a possible implementation manner, there are at least two second edge seals, and the at least two second edge seals are located on two sides of the packaging component.

[0018] In a possible implementation, two ends of the inner sealing edge along the second direction extend to the outer sealing edge respectively, wherein the second direction and the first direction have a first angle.

[0019] In a possible embodiment, the inner edge seal includes a first extension segment and a second extension segment connected to each other, and two ends of the first extension segment and the second extension segment that are opposite to each other are respectively connected to the outer edge seal, and there is a second angle between the extension direction of the first extension segment and the extension direction of the second extension segment.

[0020] In a possible implementation manner, a connection between the first extension section and the second extension section has a protruding sharp corner, and the sharp corner protrudes toward the buffer zone.

[0021] In a possible implementation, the phase change temperature of the phase change heat absorption element is greater than or equal to 110°C.

[0022] In a possible implementation, the phase-change heat absorber includes a hydrogel; or, the phase-change heat absorber includes a hydrogel and a skeleton, and the skeleton is used to support the hydrogel.

[0023] In a second aspect, the present application provides a battery pack, comprising a battery cell and the heat absorption structure provided in the first aspect, wherein the heat absorption structure is disposed on at least one surface of the battery cell.

[0024] In a possible implementation, the battery cell includes a pole, which is disposed at at least one end of the battery cell, and the heat absorption area of ​​the heat absorption structure is disposed corresponding to the end where the pole is located.

[0025] In a possible embodiment, the battery cell includes two poles, which are respectively located at two ends of the battery cell, and the heat absorption structure has two heat absorption zones, which are arranged corresponding to the two ends of the battery cell, and the buffer zone of the heat absorption structure is arranged corresponding to the middle of the battery cell.

[0026] In a third aspect, the present application provides an electrical device, including an electrical device and the battery pack provided in the second aspect above, wherein the battery pack is used to supply power to the electrical device.

[0027] The embodiments of the present application provide a heat absorption structure, a battery pack and an electrical device. The heat absorption structure includes a packaging component and a phase-change heat absorption component. The packaging component includes a buffer zone, a heat absorption zone, an outer sealing edge and an inner sealing edge. The heat absorption zone is provided for packaging the phase-change heat absorption component. The phase-change heat absorption component is provided for absorbing heat to suppress the heat diffusion of the battery cell. The outer sealing edge is provided for packaging the outer edge of the packaging component. The inner sealing edge is provided for dividing the area formed by the outer sealing edge into a relatively independent buffer zone and heat absorption zone. By making the strength of the inner sealing edge smaller than the strength of the outer sealing edge and providing the buffer zone, when the heat absorption zone produces more gas and causes the pressure to increase, the gas can first break through the inner sealing edge with lower strength and then enter the buffer zone. The buffer zone can receive the gas generated from the heat absorption zone, so that the buffer zone relieves the pressure of the heat absorption zone, thereby preventing the pressure of the heat absorption zone from being too high and squeezing the phase-change heat absorption component out of the packaging component, thereby preventing the overall failure of the heat absorption structure. Moreover, after the buffer zone is propped up, the deformation resistance of the heat absorption structure can also be improved to prevent the heat absorption structure from being ruptured by the expansion force of the battery cell. Therefore, the heat absorption structure provided in the embodiment of the present application has a better effect of suppressing heat diffusion when the battery cell is in thermal runaway.

[0028] In addition to the technical problems solved by the embodiments of the present application described above, the technical features that constitute the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions, other technical problems that can be solved by the heat absorption structure, battery pack and electrical equipment provided by the present application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Schematic diagram of the heat absorption structure provided in the embodiment of the present application Figure 1 ;

[0031] Figure 2 Schematic diagram of the heat absorption structure provided in the embodiment of the present application Figure 2 ;

[0032] Figure 3 Schematic diagram of the heat absorption structure provided in the embodiment of the present application Figure 3 ;

[0033] Figure 4 Schematic diagram of the heat absorption structure provided in the embodiment of the present application Figure 4 ;

[0034] Figure 5 Schematic diagram of the heat absorption structure provided in the embodiment of the present application Figure 5 ;

[0035] Figure 6 A schematic diagram of the structure of a package in a heat absorption structure provided in an embodiment of the present application;

[0036] Figure 7 A schematic diagram of another structure of a package in a heat absorption structure provided in an embodiment of the present application;

[0037] Figure 8 This is a schematic structural diagram of the heat absorption structure in the thickness direction provided in an embodiment of the present application.

[0038] Description of reference numerals:

[0039] 100-packaging component; 110-buffer zone; 120-heat absorption zone; 130-outer edge seal; 131-first edge seal; 132-second edge seal; 140-inner edge seal; 141-first extension section; 142-second extension section; 200-phase change heat absorption component. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals throughout represent the same or similar parts or parts with the same or similar functions. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application. The embodiments of the present application are described in detail below in conjunction with the drawings.

[0041] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are orientations or positional relationships based on the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0043] The terms "first", "second", "third" (if any) in the specification and claims of this application and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein, for example.

[0044] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or display comprising a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or display.

[0045] In the related art, multiple battery cells are arranged in the same direction, and two adjacent battery cells can be connected by a busbar, thereby connecting the multiple battery cells in series. Since the battery cells will generate a large amount of heat when they have thermal runaway, which may cause the battery pack to catch fire, in order to solve the problem that the heat of one battery cell is transferred to another adjacent battery cell and cause thermal runaway of the entire battery pack, aerogel and other insulating materials are arranged between two adjacent battery cells to suppress the transfer of heat through aerogel. However, aerogel cannot effectively suppress the heat diffusion from the battery cell to the adjacent battery cell when it has thermal runaway. There is still a possibility that one battery cell will have thermal runaway, causing thermal runaway of the entire battery pack. In addition, aerogel will affect the temperature uniformity of the battery cell under normal operating conditions or low temperature conditions.

[0046] In view of the above problems, the embodiments of the present application provide a heat absorption structure, a battery pack and an electrical device. The heat absorption structure is arranged on at least one surface of a battery cell to suppress heat diffusion of the battery cell. The packaging of the heat absorption structure is provided with a heat absorption zone and a buffer zone. The heat absorption zone is provided with a phase change heat absorption element. When thermal runaway does not occur in the battery cell, the phase change heat absorption element in the heat absorption zone can absorb the heat of the battery cell portion corresponding to the heat absorption zone, and the buffer zone will not absorb the heat of the battery cell portion corresponding to the buffer zone, thereby improving the temperature uniformity of the battery cell when thermal runaway does not occur. When thermal runaway occurs in the battery cell, the phase change heat absorption element can absorb a large amount of heat from the battery cell to undergo phase change and generate gas. The gas can first break through the inner seal with lower strength to enter the buffer zone, and then prop up the buffer zone, and then break through the outer seal to be discharged out of the buffer zone. In this way, the heat absorption structure can take into account the different usage requirements of the battery cell in both thermal runaway and non-thermal runaway scenarios.

[0047] The specific implementation of the present application is described in detail below with reference to the accompanying drawings.

[0048] Reference Figures 1 to 5 As shown, an embodiment of the present application provides a battery pack, which includes a battery cell and a heat absorption structure, the heat absorption structure is arranged on at least one surface of the battery cell, the heat absorption structure includes a packaging member 100 and a phase change heat absorption member 200, the packaging member 100 includes a buffer zone 110 and at least one heat absorption zone 120, the phase change heat absorption member 200 is arranged in the heat absorption zone 120, the phase change heat absorption member 200 is used to absorb heat, and the heat absorption zone 120 is arranged corresponding to at least one end of the battery cell.

[0049] That is to say, the package 100 may include a buffer zone 110 and a heat absorption zone 120, in which case the heat absorption zone 120 may be arranged corresponding to one end of the battery cell, or the package 100 may also include a buffer zone 110 and two heat absorption zones 120, in which case the two heat absorption zones 120 may be arranged corresponding to the two ends of the battery cell, respectively.

[0050] It is understandable that the heat absorption structure can be set between two adjacent battery cells, and the heat absorption structure can also be set on the surface of the outermost battery cell among multiple battery cells, thereby inhibiting the heat transfer of the battery cells, thereby avoiding safety problems caused by overheating of the entire battery pack.

[0051] In some embodiments, the battery cell includes two poles, which are respectively located at two ends of the battery cell, the two heat absorption areas 120 of the heat absorption structure are correspondingly arranged at the two ends of the battery cell, and the buffer zone 110 of the heat absorption structure is correspondingly arranged in the middle of the battery cell.

[0052] It should be noted that, depending on the packaging form, the battery cells may include square battery cells, soft-pack battery cells and cylindrical battery cells. The square battery cells may have two poles, and the poles of the same polarity of two adjacent square battery cells are connected by a busbar to connect multiple square battery cells in series.

[0053] Square cells can be divided into ordinary square cells and long and narrow blade cells according to their shapes. For blade cells, two poles are arranged at both ends of the length direction of the blade cells, and because the length of the blade cells is much greater than the width, when thermal runaway does not occur, the temperature of the blade cells shows a trend of being high at both ends and low in the middle. Therefore, in the battery pack composed of blade cells, the heat absorption structure can be provided with two heat absorption areas 120, and the two heat absorption areas 120 are respectively arranged corresponding to the two ends of the blade cells, and the buffer zone 110 is arranged corresponding to the middle of the blade cells.

[0054] For the square cell, the two poles can be arranged at both ends of its length direction. In this case, the heat absorption structure of the square cell can be consistent with the heat absorption structure of the blade cell, that is, the heat absorption structure can have two heat absorption areas 120. Alternatively, the two poles of the square cell can also be arranged at the same end of its length direction. When the two poles of the square cell are arranged at the same end of its length direction, the heat absorption structure arranged on the square cell can be provided with a heat absorption area 120. The heat absorption area 120 is arranged corresponding to the end of the square cell with the pole, and the buffer zone 110 can be arranged corresponding to the middle and the other end of the square cell.

[0055] Reference Figures 1 to 5 As shown, specifically, the heat absorption structure provided in the embodiment of the present application includes a package 100 and a phase change heat absorption element 200, the package 100 includes a buffer zone 110 and at least one heat absorption zone 120, the phase change heat absorption element 200 is arranged in the heat absorption zone 120, and the phase change heat absorption element 200 is used to absorb heat.

[0056] For example, refer to Figures 1 to 3 In the heat insulation structure shown in FIG. , the heat absorption area 120 and the buffer area 110 are arranged along a first direction, wherein the first direction can refer to Figures 1 to 7 The X direction in .

[0057] For example, refer to Figure 4 and Figure 5 In the heat insulation structure shown, the buffer zone 110 can be arranged on the outer peripheral side of the heat absorption zone 120, so that the heat absorption zone 120 and the buffer zone 110 form an inner and outer surrounded structure. After the heat absorption zone 120 produces gas, the gas can break through any inner sealing edge 140 around the heat absorption zone 120 and enter the buffer zone 110 outside the heat absorption zone 120.

[0058] In the present application, after the package 100 is packaged by hot pressing, the internal area of ​​the package 100 can be divided into an independent buffer area 110 and a heat absorption area 120. The heat absorption area 120 is used to encapsulate the phase change heat absorption element 200. The phase change heat absorption element 200 is used to absorb the heat of the battery cell and generate gas due to phase change when the temperature reaches the phase change temperature.

[0059] It is worth noting that due to the uneven heating characteristics of the battery cell, some parts of the battery cell heat up more severely while some parts heat up less, which will cause the overall temperature of the battery cell to be uneven, and thus affect the charging and discharging efficiency of the battery cell. Therefore, in order to improve the temperature uniformity of the battery cell during normal operation, the heat absorption structure needs to absorb heat from the parts of the battery cell with higher heating, while the parts of the battery cell with lower heating can be free of heat absorption or low-intensity heat absorption can be performed.

[0060] For example, in the case where the heat generated in the middle of the battery cell is lower than that at both ends, if the buffer zone 110 is provided with a large amount of phase change heat absorbing material like the heat absorbing zone 120, the heat absorbing structure will not only absorb the heat at the ends of the battery cell, but also absorb the heat in the middle of the battery cell, which will reduce the temperature uniformity of the battery cell. When the battery cell is in a low temperature condition, the heat absorption of the phase change heat absorbing element 200 will cause the temperature of the battery cell to continue to decrease, thereby reducing the charging and discharging efficiency of the battery cell. Therefore, it is necessary to provide a buffer zone 110 without phase change heat absorbing material or with a small amount of phase change heat absorbing material in the package 100. When the battery cell does not have thermal runaway, the buffer zone 110 will not absorb a large amount of heat in the middle of the battery cell, while the heat absorbing zone 120 can effectively absorb the heat at the ends of the battery cell, thereby improving the temperature uniformity of the battery cell.

[0061] In order to form the buffer zone 110 and the heat absorption zone 120 in the package 100 , the package 100 may have an outer edge seal 130 and an inner edge seal 140 . The outer edge of the package 100 is surrounded by the outer edge seal 130 , and the inner edge seal 140 is provided between the buffer zone 110 and the heat absorption zone 120 .

[0062] In this way, the outer sealing edge 130 can seal the outer edge of the package 100, thereby making the interior of the package 100 closed, and the inner sealing edge 140 can further divide the space inside the package 100 into relatively independent buffer areas 110 and heat absorption areas 120, which correspond to different parts of the battery cell respectively.

[0063] When the battery cell is in thermal runaway, the phase change heat absorber 200 located in the heat absorption zone 120 will absorb a large amount of heat, undergo phase change and generate gas, and the battery cell will expand and swell. Under the action of the battery cell expansion force and air pressure, the phase change heat absorber 200 will be squeezed and impacted, which will cause the phase change heat absorber 200 to deform, rupture or even squeeze out of the package 100 and fail. In order to reasonably guide the gas discharge, the strength of the inner seal 140 can be made smaller than the strength of the outer seal 130. In this way, the gas in the heat absorber can first break through the inner seal 140, then enter the buffer zone 110, and then prop up the buffer zone 110. At this time, the buffer zone 110 acts as a buffer space for the gas, which can prevent the gas from squeezing the phase change heat absorber 200 out of the package 100 and causing the overall failure of the heat absorption structure. At the same time, the gas will also drive part of the phase change heat absorber 200 into the buffer zone 110, so that the phase change heat absorber 200 can effectively absorb the heat of the battery cell, thereby effectively suppressing the thermal diffusion of the battery cell.

[0064] It should be understood that when the blade cell experiences thermal runaway, the middle part of the blade cell expands and bulges more severely. After the buffer zone 110 arranged in the middle part of the blade cell is propped up, it has a certain flexibility and can better resist the expansion force of the cell, thereby making the heat absorption structure have better anti-deformation performance, thereby avoiding the package 100 from rupture due to the expansion force of the cell.

[0065] The heat absorption structure provided in the embodiment of the present application includes a package 100 and a phase-change heat absorption element 200. The package 100 includes a buffer zone 110, a heat absorption area 120, an outer edge seal 130 and an inner edge seal 140. The heat absorption area 120 is provided to encapsulate the phase-change heat absorption element 200. The phase-change heat absorption element 200 is provided to absorb heat to suppress the heat diffusion of the battery cell. The buffer zone 110 is provided to reduce the influence of the heat absorption structure on the temperature uniformity of the battery cell in a non-thermal runaway scenario, and when the battery cell is in thermal runaway, the gas generated from the heat absorption area 120 is received to reduce the pressure of the heat absorption area 120, thereby preventing the phase-change heat absorption element 200 from being squeezed out of the package 100 due to excessive gas pressure in the heat absorption area 120. After the buffer zone 110 is propped up, the deformation resistance of the heat absorption structure can also be improved to prevent the packaging structure from being ruptured by the expansion force of the battery cell. By setting an outer sealing edge 130 to seal the outer edge of the package 100, and by setting an inner sealing edge 140 to divide the area enclosed by the outer sealing edge 130 into relatively independent buffer zone 110 and heat absorption zone 120, by making the strength of the inner sealing edge 140 smaller than the strength of the outer sealing edge 130, when the heat absorption zone 120 produces more gas and causes the pressure to increase, the gas can first break through the inner sealing edge 140 with lower strength and then enter the buffer zone 110, so that the buffer zone 110 buffers the pressure of the heat absorption zone 120, thereby preventing the phase change heat absorption element 200 from being squeezed out of the package 100 due to excessive pressure in the heat absorption zone 120, which causes the heat absorption structure to fail as a whole. Therefore, the heat insulation effect of the heat absorption structure provided in the embodiment of the present application is good, and will not affect the normal use of the battery cell.

[0066] Reference Figures 1 to 7 As shown, it can be understood that when the heat absorption zone 120 produces a lot of gas and breaks through the inner seal 140 to enter the buffer zone 110, when the pressure of the buffer zone 110 increases to a certain extent, the gas in the buffer zone 110 needs to be discharged. Therefore, in order to guide the gas to be discharged in an orderly manner, in a possible embodiment, the outer seal 130 includes a first seal 131 and a second seal 132, and the strength a1 of the first seal 131, the strength a2 of the inner seal 140, and the strength a3 of the second seal 132 meet the following conditions: a2 <a3<a1。

[0067] In this way, when the phase-change heat absorber 200 generates gas to a certain extent after absorbing heat, the gas first breaks through the inner edge seal 140 and enters the buffer zone 110. When the gas pressure in the buffer zone 110 increases to a certain extent, the gas can continue to break through the second edge seal 132 to be discharged out of the heat absorption structure, and then part of the heat can be taken away by the gas, thereby effectively suppressing the thermal diffusion of the battery cell. The first edge seal 131 is relatively strong and will not break, so as to ensure that the phase-change heat absorber 200 is always encapsulated in the package 100, thereby avoiding failure of the heat absorption structure.

[0068] The second edge seal 132 may be disposed at one or two outer edges of the buffer zone 110 to guide the gas to be discharged in different directions, and one or more second edge seals 132 may be disposed on the same outer edge.

[0069] In some embodiments, at least two second edge seals 132 are disposed on both sides of the package 100. At least two second edge seals 132 may be disposed on two adjacent sides or two opposite sides of the package 100 to guide the gas to be discharged in different directions.

[0070] It should be noted that the first edge seal 131, the inner edge seal 140 and the second edge seal 132 can achieve different strengths through different heat sealing temperatures and heat sealing processes. The strengths of the first edge seal 131, the inner edge seal 140 and the second edge seal 132 can be obtained through relevant tests. For example, the strengths of the first edge seal 131, the inner edge seal 140 and the second edge seal 132 can be obtained with reference to the test method in the test standard QB / T2358-1998. In addition, due to the phase change heat absorption of the phase change heat absorption element 200, the gas generated by the phase change heat absorption element 200 breaks through the inner edge seal 140 and the second edge seal 132 in turn and is discharged from the heat absorption structure. It can also be known that the strengths of the inner edge seal 140, the second edge seal 132 and the first edge seal 131 decrease in turn.

[0071] For example, the strength a1 of the first edge seal 131 may be between 60-100 N / mm, the strength a2 of the inner edge seal 140 may be between 20-50 N / mm, and the strength a3 of the second edge seal 132 may be between 40-80 N / mm.

[0072] In some embodiments, the first edge seal 131 is at least disposed around an outer edge of the heat absorption zone 120 , and the second edge seal 132 is located at at least one outer edge of the buffer zone 110 .

[0073] In a possible implementation, a partial area of ​​the first edge seal 131 extends to the outer edge of the buffer zone 110 .

[0074] That is to say, the outer edge of the buffer zone 110 is composed of the second edge seal 132 and part of the first edge seal 131. In this way, it can be ensured that when the pressure of the buffer zone 110 is relatively high, the second edge seal 132 at the outer edge of the buffer zone 110 is opened by the gas, while the first edge seal 131 is not opened by the gas, thereby preventing the phase change heat absorber 200 from being squeezed out of the package 100.

[0075] It should be noted that the outer edge of the buffer zone 110 mentioned in the present embodiment can be understood as the junction between the buffer zone 110 and other structures other than the heat absorption structure, and the outer edge of the heat absorption zone 120 mentioned in the present embodiment can be understood as the junction between the heat absorption zone 120 and other structures other than the heat absorption structure, or the outer edge of the heat absorption zone 120 can be understood as the junction between the heat absorption zone 120 and other structures of the heat absorption structure itself. For example, when the buffer zone 110 is surrounded on the outside of the heat absorption zone 120, the junction between the heat absorption zone 120 and the buffer zone 110 is the outer edge of the heat absorption zone 120.

[0076] In some embodiments, the ratio of the strength of the first edge seal 131 to the strength of the inner edge seal 140 satisfies: a1 / a2≥2. This arrangement can ensure the strength of the first edge seal 131, thereby preventing the heat absorption structure from failing, and at the same time allow the gas to break through the inner edge seal 140 and the second edge seal 132 in sequence, thereby guiding the gas to be discharged in an orderly manner.

[0077] In a possible implementation, there are two heat absorption areas 120, and the buffer zone 110 is located between the two heat absorption areas 120. In this way, for the battery cell with two poles arranged at both ends, the heat absorption effect of the heat absorption structure is better, and it will not affect the middle part of the battery cell with lower heat generation, thereby avoiding increasing the temperature difference of the battery cell.

[0078] It should be noted that when the heat absorption zone 120, the buffer zone 110 and the heat absorption zone 120 are arranged sequentially along the first direction, there is an inner sealing edge 140 between the buffer zone 110 and the two adjacent heat absorption zones 120, and the gas of the two heat absorption zones 120 can break through the corresponding inner sealing edges 140 and enter the buffer zone 110.

[0079] It should be understood that the settings of the buffer zone 110 and the heat absorption zone 120 need to be balanced to ensure that the heat absorption structure has enough space for orderly exhaust, while ensuring that the heat absorption structure has enough space to accommodate a sufficient number of phase change heat absorption elements 200. Therefore, in some embodiments, when the buffer zone 110 and the heat absorption zone 120 are arranged along the first direction, in the first direction, the length L1 of the package 100 and the length L2 of the buffer zone 110 satisfy: L1 / 20≤L2≤L1 / 3.

[0080] When the heat absorption structure is provided with heat absorption areas 120 on both sides of the buffer zone 110, if L2≤L1 / 20, the buffer zone 110 does not have enough space for receiving the gas from the heat absorption area 120, and if L2≥L1 / 3, the space of the heat absorption area 120 is too small to accommodate a sufficient amount of the phase change heat absorption element 200.

[0081] Among them, L1 and L2 can refer to Figure 1 and Figure 2 The annotations in .

[0082] In a possible implementation, the ratio of the thickness of the buffer region 110 to the thickness of the heat absorption region 120 is less than or equal to 0.1. That is, the thickness T1 of the buffer region 110 and the thickness T2 of the heat absorption region 120 satisfy: T1 / T2≤0.1.

[0083] When the buffer zone 110 is evacuated to a vacuum or near vacuum, the atmospheric pressure will force the two layers of the film of the package 100 to be in close contact with each other, and the thickness of the buffer zone 110 is substantially equal to the thickness of the two layers of the film of the package 100. Alternatively, when there is a cavity in the buffer zone 110 and there is a gap between the two layers of the film of the package 100, the thickness of the buffer zone 110 is equal to the sum of the thickness of the two layers of the film of the package 100 and the gap between the two layers of the film. Since the phase change heat absorbing element 200 is provided in the heat absorbing zone 120, its thickness will be much greater than the thickness of the buffer zone 110.

[0084] It should be understood that T1 and T2 described in the above embodiments should be obtained when the outer edge seal 130 and the inner edge seal 140 are intact. If the outer edge seal 130 or the inner edge seal 140 is broken, the buffer zone 110 will be connected to the outside, or the buffer zone 110 and the heat absorption zone 120 will be connected, some gas will enter the buffer zone 110, and the thickness of the buffer zone 110 will increase.

[0085] Among them, T1 and T2 can refer to Figure 8 The annotations in .

[0086] In a possible implementation, when the buffer zone 110 and the heat absorption zone 120 are arranged along the first direction, in the first direction, the length L2 of the buffer zone 110 and the length L3 of the second edge sealing 132 satisfy: 0.1≤L3 / L2≤1.

[0087] It is understandable that in order to ensure that the gas in the buffer zone 110 can be discharged smoothly through the second edge seal 132, L3 needs to be greater than or equal to 0.1*L2. In order to guide the orderly discharge of the gas, the opening formed after the second edge seal 132 is broken open should not be too large to avoid the gas from diffusing everywhere. Therefore, L3 should be less than or equal to L2.

[0088] Among them, L3 can refer to Figure 1 and Figure 2 The annotations in .

[0089] In a possible implementation, the projection shape of the second edge sealing 132 in the thickness direction of the package 100 includes a quadrilateral (eg, a rectangle, a trapezoid, etc.) and / or a triangle, so that different shapes can be set according to different requirements.

[0090] Reference Figure 1 , Figure 3 and Figure 6As shown, in a possible implementation manner, both ends of the inner edge seal 140 along the second direction extend to the outer edge seal 130. When heat absorption areas 120 are provided on both sides of the buffer zone 110 along the first direction, or when the buffer zone 110 is surrounded by two heat absorption areas 120, there is an inner edge seal 140 between the buffer zone 110 and the two adjacent heat absorption areas 120, and the two inner edge seals 140 are provided in parallel.

[0091] The second direction has a first angle with the first direction. For example, the first angle may be 90°. That is, the second direction is perpendicular to the first direction. Figures 1 to 7 in the Y direction.

[0092] Reference Figure 2 and Figure 7 As shown, in a possible embodiment, the inner edge seal 140 includes a first extension section 141 and a second extension section 142 connected to each other, and the two ends of the first extension section 141 and the second extension section 142 that are opposite to each other are respectively connected to the outer edge seal 130, and there is a second angle between the extension direction of the first extension section 141 and the extension direction of the second extension section 142.

[0093] In a specific implementation, a connection between the first extension section 141 and the second extension section 142 has a protruding sharp corner, and the sharp corner protrudes toward the buffer zone 110 .

[0094] In the above-mentioned setting, a sharp corner is formed at the connection between the first extension section 141 and the second extension section 142, and the sharp corner protrudes toward the buffer zone 110. Since the gas has a tendency to move toward the buffer zone 110, this is more conducive to the gas in the heat absorption zone 120 squeezing the inner sealing edge 140, and then breaking through the inner sealing edge 140 from the sharp corner.

[0095] In a possible implementation, the phase change temperature of the phase change heat absorbing element 200 is greater than or equal to 110° C. Thus, when the temperature of the phase change heat absorbing element 200 reaches above 110° C., the phase change heat absorbing material of the phase change heat absorbing element 200 will change from a solid phase to a gas phase, and absorb a large amount of heat in the process, thereby effectively suppressing the heat diffusion of the battery cell.

[0096] For example, the phase change heat absorber 200 may include a hydrogel, which satisfies a phase change temperature greater than or equal to 110° C., and a phase change latent heat of the hydrogel of 500 kJ / mol. The phase change process can effectively absorb the heat of the battery cell to inhibit the thermal diffusion of the battery cell.

[0097] For another example, the phase change heat absorber 200 may include a hydrogel and a skeleton, wherein the skeleton is used to support the hydrogel to improve the strength of the phase change heat absorber 200. The hydrogel satisfies the phase change temperature greater than or equal to 110°C, and the phase change latent heat of the hydrogel is 500 kJ / mol. The phase change process can effectively absorb the heat of the battery cell to inhibit the thermal diffusion of the battery cell.

[0098] In addition, an embodiment of the present application also provides an electrical equipment, including an electrical device and a battery pack, wherein the battery pack is used to supply power to the electrical device.

[0099] Among them, the structure and working principle of the battery pack have been described in detail in the above embodiments and will not be repeated here.

[0100] Exemplarily, the electrical equipment may be a vehicle, the electrical device may be an electric motor, the battery pack may provide electrical energy to the electric motor, and the vehicle is then driven by the electric motor. Alternatively, the electrical equipment may be a charging pile, the electrical device may be an energy storage cabinet, and the battery pack is used to provide electrical energy to the energy storage cabinet, and the charging pile is then powered.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery pack, characterized in that: include: A heat absorbing structure, comprising: A package (100), the package (100) comprising a buffer zone (110) and two heat absorption zones (120), the buffer zone (110) and the heat absorption zone (120) being arranged along a first direction, and the buffer zone (110) being located between the two heat absorption zones (120); The package further comprises an outer edge seal (130) and an inner edge seal (140), the outer edge of the package (100) being surrounded by the outer edge seal (130), the inner edge seal (140) being located between the buffer zone (110) and the heat absorption zone (120), and the strength of the inner edge seal (140) being less than the strength of the outer edge seal (130); A phase-change heat absorbing element (200), the phase-change heat absorbing element (200) being arranged in the heat absorbing area (120), the phase-change heat absorbing element (200) being used to absorb heat; A battery cell, the battery cell comprising: two poles, the two poles being located at two ends of the battery cell respectively, the two heat absorption areas (120) being arranged corresponding to the two ends of the battery cell, and the buffer area (110) being arranged corresponding to the middle of the battery cell.

2. The battery pack according to claim 1, characterized in that: The outer edge seal (130) comprises a first edge seal (131) and a second edge seal (132), wherein the strength a1 of the first edge seal (131), the strength a2 of the inner edge seal (140), and the strength a3 of the second edge seal (132) satisfy: a2 <a3<a1。 3. The battery pack according to claim 2, characterized in that: The ratio of the strength of the first edge seal (131) to the strength of the inner edge seal (140) satisfies: a1 / a2≥2.

4. The battery pack according to claim 2 or 3, characterized in that: The second edge seal (132) is located at at least one outer edge of the buffer zone (110).

5. The battery pack according to claim 4, characterized in that: A partial area of ​​the first edge seal (131) extends to the outer edge of the buffer zone (110).

6. The battery pack according to claim 2 or 3, characterized in that: In the first direction, a length L1 of the package (100) and a length L2 of the buffer zone (110) satisfy: L1 / 20≤L2≤L1 / 3.

7. The battery pack according to any one of claims 1 to 3, characterized in that: The ratio of the thickness of the buffer zone (110) to the thickness of the heat absorption zone (120) is less than or equal to 0.

1.

8. The battery pack according to claim 6, characterized in that: In the first direction, a length L2 of the buffer zone (110) and a length L3 of the second edge sealing (132) satisfy: 0.1≤L3 / L2≤1.

9. The battery pack according to claim 2 or 3, characterized in that: The projection shape of the second edge seal (132) in the thickness direction of the package (100) includes a quadrilateral and / or a triangle.

10. The battery pack according to claim 2 or 3, characterized in that: There are at least two second edge seals (132), and at least two of the second edge seals (132) are located on two sides of the packaging component (100).

11. The battery pack according to claim 2 or 3, characterized in that: Two ends of the inner sealing edge (140) along the second direction respectively extend to the outer sealing edge (130); Wherein, the first direction and the second direction have a first angle.

12. The battery pack according to any one of claims 1 to 3, characterized in that: The inner edge seal (140) comprises a first extension section (141) and a second extension section (142) which are connected to each other, and two ends of the first extension section (141) and the second extension section (142) which are away from each other are respectively connected to the outer edge seal (130), and an extension direction of the first extension section (141) and an extension direction of the second extension section (142) form a second angle.

13. The battery pack according to claim 12, characterized in that: The connection between the first extension section (141) and the second extension section (142) has a protruding sharp corner, and the sharp corner protrudes towards the buffer zone (110).

14. The battery pack according to any one of claims 1 to 3, characterized in that: The phase change temperature of the phase change heat absorption element (200) is greater than or equal to 110°C.

15. The battery pack according to claim 14, characterized in that: The phase-change heat-absorbing element (200) comprises a hydrogel; Alternatively, the phase-change heat-absorbing element (200) comprises a hydrogel and a skeleton, wherein the skeleton is used to support the hydrogel.

16. The battery pack according to any one of claims 1 to 3, characterized in that: The heat absorption structure is arranged on at least one surface of the battery core.

17. An electrical equipment, characterized in that: It comprises an electric device and a battery pack as described in any one of claims 1 to 16, wherein the battery pack is used to supply power to the electric device.

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