Heat absorption unit, battery pack and electric equipment
By embedding multi-layer skeletons in the heat absorbing material, the outer skeleton buffers heat propagation in the high-temperature zone, and the intermediate skeleton quickly conducts heat, solving the heat diffusion problem caused by thermal runaway in the battery pack, enhancing the anti-compression performance and thermal management efficiency.
Patent Information
- Application Number
- CN202421656116.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-12
- Publication Date
- 2025-08-05
- Estimated Expiration
- 2034-07-12
AI Technical Summary
In the prior art, when the battery cell in the battery pack is thermally out of control, heat is quickly transferred to adjacent battery cells, causing heat diffusion, and the heat absorbing material is prone to deformation and failure under pressure, which cannot effectively prevent heat diffusion.
Multi-layer skeletons are embedded in the heat absorbing material. The thermal conductivity of the outer skeleton is smaller than that of the intermediate skeleton, forming a composite structure. The outer skeleton buffers heat propagation in the high-temperature zone, and the intermediate skeleton quickly conducts heat to prevent heat from spreading to adjacent cells in a short time.
Effectively absorb heat generated by the out-of-control battery cell, prevent heat diffusion, enhance anti-compression performance, reduce high temperatures in the out-of-control area, and improve thermal management efficiency.
Smart Images
Figure CN223193845U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of battery thermal management, and particularly relates to a heat absorption unit, a battery pack, and an electrical device. Background Art
[0002] With the continuous popularization of new energy vehicles, their safety issues have attracted more and more attention from all aspects. Due to thermal abuse, mechanical abuse, etc. of the battery, potential safety hazards will be brought to the battery, and even cause thermal runaway of the battery cells. When thermal runaway occurs in the battery cells in the battery pack, a large amount of heat is generated inside, resulting in a rapid increase in the temperature of the battery cells and being transmitted to adjacent battery cells. If effective isolation means are not taken, the temperature of adjacent battery cells will also rise rapidly and thermal diffusion will occur. Utility Model Content
[0003] Embodiments of this application provide a heat absorption unit, a battery pack, and an electrical device to solve at least one of the above-mentioned technical problems.
[0004] The heat absorption unit of the embodiments of this application is used to be arranged between the cell surfaces of two adjacent battery cells in a battery pack. The heat absorption unit includes:
[0005] A heat absorption material; and
[0006] A multi-layered framework, where multiple layers of the framework are embedded in the heat absorption material. The multi-layered framework includes an outer framework and an intermediate framework, and the thermal conductivity of the outer framework is less than that of the intermediate framework.
[0007] In some embodiments, multiple layers of the framework are arranged parallel to the cell surface;
[0008] The outer framework is closer to the cell surface than the intermediate framework.
[0009] In some embodiments, the outer framework includes a first outer framework and a second outer framework, and the intermediate framework is located between the first outer framework and the second outer framework;
[0010] The thermal conductivities of both the first outer framework and the second outer framework are less than that of the intermediate framework.
[0011] In some embodiments, the multi-layered framework further includes a transition framework, and the transition framework includes:
[0012] One or more first transition frameworks arranged between the first outer framework and the intermediate framework. Along the direction from the intermediate framework to the first outer framework, the thermal conductivity of the multi-layered framework shows a decreasing trend; and / or
[0013] One or more second transition skeletons disposed between the second outer skeleton and the intermediate skeleton, along the direction from the intermediate skeleton to the second outer skeleton, the thermal conductivity of the multi-layer skeletons shows a decreasing trend.
[0014] In some embodiments, the thermal conductivity of the intermediate skeleton is greater than 100 W / (m*K).
[0015] In some embodiments, the thermal conductivity of the outer skeleton is less than 1 W / (m*K).
[0016] In some embodiments, the ratio between the thermal conductivity of the intermediate skeleton and the thermal conductivity of the outer skeleton is greater than 100.
[0017] In some embodiments, the thickness of the intermediate skeleton is greater than the thicknesses of the first outer skeleton and the second outer skeleton.
[0018] In some embodiments, the thickness ratio of the first outer skeleton in the multi-layer skeletons is 20% - 30%; and / or, the thickness ratio of the second outer skeleton in the multi-layer skeletons is 20% - 30%.
[0019] In some embodiments, both the outer skeleton and the intermediate skeleton are hollow structures.
[0020] In some embodiments, the structural shapes of the outer skeleton and the intermediate skeleton are different.
[0021] In some embodiments, the heat absorption unit further includes a packaging shell, and the heat absorption material and the multi-layer skeletons are both disposed inside the packaging shell.
[0022] The battery pack according to the embodiments of the present application includes:
[0023] Multiple battery cells; and
[0024] One or more heat absorption units according to any one of the above embodiments, the heat absorption unit is used to absorb the heat generated by the battery cells.
[0025] The electrical equipment according to the embodiments of the present application includes the battery pack according to the above embodiments.
[0026] In the heat absorption unit, battery pack, and electrical equipment according to the embodiments of the present application, in the first aspect, the heat absorption material can effectively absorb the heat generated by the out-of-control battery cell through phase change, thereby preventing heat diffusion. In the second aspect, adding multiple layers of frameworks to the heat absorption material can enhance the compression resistance of the heat absorption unit. In the third aspect, the thermal conductivity of the outer framework is less than that of the middle framework. That is to say, when the battery cell undergoes thermal runaway, a high temperature appears locally in the battery cell, and the high-temperature heat propagates to the heat absorption material. When passing through the outer framework, due to the low thermal conductivity of the outer framework, only the heat absorption material near the high-temperature area is consumed. After the material near the high-temperature area of the outer framework is consumed, the heat propagates to the middle framework. Due to the high thermal conductivity of the middle framework, the heat quickly propagates throughout the middle framework. In this way, not only can the high temperature in the out-of-control area be reduced, but compared with the heat absorption unit with a single framework structure, more heat absorption materials can play a role (in the heat absorption unit with a single framework structure, due to the uniform thickness of the heat absorption material, it is easy to cause the material in the high heat generation area to be consumed completely, while the materials in other areas are not consumed; while in the present application, the entire middle framework can be fully utilized), thus efficiently solving the problem of heat diffusion.
[0027] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings. Among them:
[0029] Figure 1 is a partial structural schematic diagram of a battery pack according to some embodiments of the present application;
[0030] Figure 2 is a structural schematic diagram of a heat absorption unit according to some embodiments of the present application;
[0031] Figure 3 is a schematic diagram of heat propagation of a heat absorption unit in related technologies;
[0032] Figure 4 is a schematic diagram of heat propagation of a heat absorption unit according to some embodiments of the present application;
[0033] Figure 5 is a schematic diagram of heat propagation of a heat absorption unit according to some embodiments of the present application;
[0034] Figure 6It is a schematic diagram of heat propagation of the heat absorption unit in some embodiments of the present application;
[0035] Figure 7 It is a schematic structural diagram of the heat absorption unit in some embodiments of the present application;
[0036] Figure 8 It is a schematic diagram of the thermal conductivity distribution of the multi-layer skeleton in some embodiments of the present application;
[0037] Figure 9 It is a schematic structural diagram of the single-layer skeleton in some embodiments of the present application;
[0038] Figure 10 It is a schematic structural diagram of the single-layer skeleton in some embodiments of the present application;
[0039] Figure 11 It is a schematic structural diagram of the electrical equipment in some embodiments of the present application.
[0040] Description of reference numerals:
[0041] Heat absorption unit 10, heat absorption material 11, skeleton 12, outer skeleton 121, first outer skeleton 1211, second outer skeleton 1212, intermediate skeleton 122, transition skeleton 123, first transition skeleton 1231, second transition skeleton 1232, encapsulation structure 13, battery cell 20, battery cell surface 201, battery pack 100, vehicle body 200, electrical equipment 1000. Specific embodiments
[0042] The following details the embodiments of the present application. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application and should not be construed as a limitation to the present application.
[0043] Please refer to Figure 1 and Figure 2 , the embodiments of the present application provide a heat absorption unit 10. The heat absorption unit 10 is used to be disposed between the battery cell surfaces 201 of two adjacent battery cells 20 in the battery pack 100. The heat absorption unit 10 includes a heat absorption material 11 and a multi-layer skeleton 12. The multi-layer skeleton 12 is embedded in the heat absorption material 11. The multi-layer skeleton 12 includes an outer skeleton 121 and an intermediate skeleton 122. The thermal conductivity of the outer skeleton 121 is less than that of the intermediate skeleton 122.
[0044] In the heat absorption unit 10 of the embodiment of the present application, in the first aspect, the heat absorption material 11 can effectively absorb the heat generated by the out-of-control battery cell 20 through phase change, thereby preventing heat diffusion. In the second aspect, adding a multi-layered framework 12 to the heat absorption material 11 can enhance the compression resistance of the heat absorption unit 10. In the third aspect, the thermal conductivity of the outer framework 121 is less than that of the intermediate framework 122, which can reduce the high temperature in the out-of-control area and enable more heat absorption material 11 to play a role, thus efficiently solving the problem of heat diffusion.
[0045] Specifically, the battery pack 100 may include multiple battery cells 20. Among them, the length direction of the battery pack 100 is Figure 1 the X direction in Figure 1 the Y direction in Figure 1 the Z direction in. The multiple battery cells 20 are arranged in sequence along the height direction Z of the battery pack 100. The cell surfaces 201 of two adjacent battery cells 20 face each other and are the large surfaces of the battery cells 20 ( Figure 1 the plane where the X direction and the Y direction are located in). The heat absorption unit 10 is arranged between the cell surfaces 201 of two adjacent battery cells 20 to facilitate heat absorption of the two adjacent battery cells 20.
[0046] The heat absorption unit 10 includes a heat absorption material 11 and a multi-layered framework 12. The heat absorption material 11 can adopt a phase change material with high heat absorption to effectively absorb the heat generated by the out-of-control battery cell 20 through phase change, thereby preventing heat diffusion. The multi-layered framework 12 is embedded in the heat absorption material 11. That is to say, the multi-layered framework 12 is placed inside the heat absorption material 11, and the heat absorption material 11 fills the gaps between the multi-layered framework 12, forming a tight combination between the two. The multi-layered framework 12 can not only provide structural support for the heat absorption material 11, but also promote the uniform distribution and effective conduction of heat through its multi-layered structure. Among them, the framework 12 can be made of materials such as polymers, metals, and ceramics. The multi-layered framework 12 includes an outer framework 121 and an intermediate framework 122. The thermal conductivity of the outer framework 121 is less than that of the intermediate framework 122.
[0047] In the related art, when a battery cell in a battery pack undergoes thermal runaway, a large amount of heat is generated inside it, resulting in a rapid increase in the temperature of the battery cell and being transmitted to adjacent battery cells. If no effective isolation means are taken, the temperatures of adjacent battery cells will also rise rapidly and thermal diffusion will occur.
[0048] In the embodiment of the present application, the heat absorption unit 10 is arranged between the cell surfaces 201 of two adjacent battery cells 20 in the battery pack 100. The heat absorption unit 10 includes a heat absorption material 11, and the heat absorption material 11 can effectively absorb the heat generated by the out-of-control battery cell 20 through phase change, thereby preventing heat diffusion.
[0049] Furthermore, since the heat-absorbing material is generally soft and has a large deformation under pressure, the material inside the encapsulation housing is easily extruded, leading to thermal management failure and inability to prevent heat diffusion.
[0050] Therefore, in the embodiments of the present application, a multi-layered framework 12 is added to the heat-absorbing material 11 to form a composite material structure as a whole, which can enhance the compression resistance of the heat-absorbing unit 10.
[0051] Please refer to Figure 3 , and through research, it is found that when the structure of the heat-absorbing unit is as Figure 3 shown, the framework structure is single and mainly plays a role in support and heat insulation. When the battery cell gets out of control, the heat generation amount from the out-of-control point of the out-of-control battery cell to the end face of the battery cell shows a distribution from high to low. Therefore, the heat generation amount in the local area where the battery cell gets out of control is large, and the heat generation amount in other areas is small. Currently, the thickness of the heat-absorbing material is uniform, which easily leads to the material in the high heat generation area being consumed completely, while the material in other areas is not consumed. The schematic diagram of heat propagation is as Figure 3 . If the material thickness is insufficient, after the material in the high heat generation area is consumed completely, the temperature of the corresponding area of the adjacent battery cell will also increase, so there is still a risk of heat diffusion.
[0052] If a framework with a high thermal conductivity is used, the heat can be transferred to the low-temperature area inside the heat-absorbing material, thus improving the above situation. However, the high-thermal-conductivity framework will also quickly conduct the heat from the out-of-control battery cell to the adjacent battery cell. In this regard, the high-thermal-conductivity framework will also increase the risk of heat diffusion between battery cells.
[0053] Therefore, in the embodiments of the present application, the heat-absorbing unit 10 includes a multi-layered framework 12, and the thermal conductivity of the outer framework 121 is less than that of the middle framework 122. That is to say, the outer framework 12 uses a material with a low thermal conductivity, and the middle framework 122 uses a material with a high thermal conductivity. When the battery cell 20 has a thermal runaway, a high temperature appears locally in the battery cell 20, and the high-temperature heat propagates to the heat-absorbing material 11. When passing through the outer framework 121, since the thermal conductivity of the outer framework 121 is relatively low, only the heat-absorbing material 11 near the high-temperature area is consumed, as Figure 4 shown. After the material near the high-temperature area of the outer framework 121 is consumed completely, the heat further propagates to the inner layer of the heat-absorbing material 11. When the heat propagates to the middle framework 122 with a high thermal conductivity, the heat quickly propagates in the direction parallel to the battery cell surface 201 through the middle framework 122, as Figure 5 shown. After the heat propagates in the direction parallel to the battery cell surface 201, when the heat-absorbing material 11 on the middle framework 122 undergoes a phase change and is consumed, the heat further propagates to the outer framework 121 with a low thermal conductivity on the other side, and finally propagates to the adjacent battery cell 20, as Figure 6 shown.
[0054] Based on the functions of support and heat insulation, the multi-layer framework 12 in the embodiments of the present application adds a heat dissipation function, spreading part of the heat to the low-temperature area without negative effects. The heat is dispersed in the direction parallel to the cell surface 201. On the one hand, the maximum temperature in the out-of-control area is reduced. On the other hand, more heat-absorbing materials 11 play a role in the early stage, thus more efficiently solving the problem of heat diffusion.
[0055] Please refer to Figure 1 and Figure 2 , in some embodiments, the multi-layer framework 12 is arranged parallel to the cell surface 201.
[0056] That is to say, the plane where each layer of the framework 12 in the multi-layer framework 12 is located is parallel to the cell surface 201 (i.e., Figure 1 the plane where the X direction and the Y direction are located in ). In this way, not only is the manufacturing process of the multi-layer framework 12 simple, but it is also beneficial to disperse the heat in the direction parallel to the cell surface 201. Among them, the outer framework 121 is closer to the cell surface 201 than the middle framework 122.
[0057] Please refer to Figure 2 , in some embodiments, the outer framework 121 includes a first outer framework 1211 and a second outer framework 1212. The middle framework 122 is located between the first outer framework 1211 and the second outer framework 1212. The thermal conductivities of both the first outer framework 1211 and the second outer framework 1212 are less than that of the middle framework 122.
[0058] Specifically, in the embodiments of the present application, the total number of layers N of the framework 12 ≥ 3. The first outer framework 1211, the middle framework 122, and the second outer framework 1212 are arranged in sequence along the height direction Z of the battery pack 100, forming a sandwich structure. It can be understood that since both the first outer framework 1211 and the second outer framework 1212 are closer to the respective adjacent cell surfaces 201 relative to the middle framework 122, they both belong to the outer framework 121. In one example, the multi-layer framework 12 is a symmetric structure along the height direction Z of the battery pack 100.
[0059] The thermal conductivities of both the first outer framework 1211 and the second outer framework 1212 are less than that of the middle framework 122. Among them, the thermal conductivities of the first outer framework 1211 and the second outer framework 1212 are not limited. It can be that the thermal conductivity of the first outer framework 1211 is less than that of the second outer framework 1212; or, the thermal conductivity of the first outer framework 1211 is equal to that of the second outer framework 1212; or, the thermal conductivity of the first outer framework 1211 is greater than that of the second outer framework 1212.
[0060] Please combine with Figures 4 to 6, when the battery cell 20 undergoes thermal runaway, a high temperature appears locally in the battery cell 20, and the high-temperature heat spreads to the heat-absorbing material 11. When passing through the first outer-layer framework 1211, since the thermal conductivity of the first outer-layer framework 1211 is relatively low, only the heat-absorbing material 11 near the high-temperature area is consumed, as Figure 4 shown. After the material near the high-temperature area of the first outer-layer framework 1211 is consumed, the heat further spreads to the inner layer of the heat-absorbing material 11. When the heat spreads to the intermediate framework 122 with a high thermal conductivity, the heat quickly spreads in the direction parallel to the battery cell surface 201 through the intermediate framework 122, as Figure 5 shown. After the heat spreads in the direction parallel to the battery cell surface 201, when the heat-absorbing material 11 on the intermediate framework 122 undergoes a phase change and is consumed, it further spreads to the second outer-layer framework 1212 with a low thermal conductivity on the other side, and finally spreads to the adjacent battery cell 20, as Figure 6 shown.
[0061] Please refer to Figure 7 , in some embodiments, the multi-layer framework 12 further includes a transition framework 123. The transition framework 123 includes one or more first transition frameworks 1231. One or more first transition frameworks 1231 are disposed between the first outer-layer framework 1211 and the intermediate framework 122. Along the direction from the intermediate framework 122 to the first outer-layer framework 1211, the thermal conductivity of the multi-layer framework 12 shows a decreasing trend. And / or, the transition framework 123 includes one or more second transition frameworks 1232. One or more second transition frameworks 1232 are disposed between the second outer-layer framework 1212 and the intermediate framework 122. Along the direction from the intermediate framework 122 to the second outer-layer framework 1212, the thermal conductivity of the multi-layer framework 12 shows a decreasing trend.
[0062] Specifically, taking the transition framework 123 including one first transition framework 1231 and one second transition framework 1232 as an example, the total number of layers N of the framework 12 is 5. Along the height direction Z of the battery pack 100, they are in sequence: the first outer-layer framework 1211, the first transition framework 1231, the intermediate framework 122, the second transition framework 1232, and the second outer-layer framework 1212. The thermal conductivity of the first outer-layer framework 1211 < the thermal conductivity of the first transition framework 1231 < the thermal conductivity of the intermediate framework 122 > the thermal conductivity of the second transition framework 1232 > the thermal conductivity of the second outer-layer framework 1212. Of course, in other examples, the transition framework 123 may also include multiple first transition frameworks 1231 and multiple second transition frameworks 1232.
[0063] Please combine with Figure 8, in the multi-layer skeleton 12, the thermal conductivity gradually decreases from the middle to the outer layer. That is, the thermal conductivity of the middle skeleton 122 is the largest, and the thermal conductivity of the outer skeleton 121 is the smallest, showing a gradually decreasing trend, which can specifically be a stepped decrease (not required to be strictly distributed according to an arithmetic progression).
[0064] Please refer to Figure 2 , in some embodiments, the thermal conductivity of the middle skeleton 122 is greater than 100 W / (m*K).
[0065] For example, the thermal conductivity of the middle skeleton 122 is 110 W / (m*K), 120 W / (m*K), 130 W / (m*K), 140 W / (m*K), 150 W / (m*K), 160 W / (m*K), 170 W / (m*K), 180 W / (m*K), 190 W / (m*K), 200 W / (m*K), or any other value greater than 100 W / (m*K), and no further examples are given here. The thermal conductivity of the middle skeleton 122 being greater than 100 W / (m*K) can enable heat to be propagated as soon as possible in the direction parallel to the cell surface 201.
[0066] Please refer to Figure 2 , in some embodiments, the thermal conductivity of the outer skeleton 121 is less than 1 W / (m*K).
[0067] For example, the thermal conductivity of the outer skeleton 121 is 0.1 W / (m*K), 0.2 W / (m*K), 0.3 W / (m*K), 0.4 W / (m*K), 0.5 W / (m*K), 0.6 W / (m*K), 0.7 W / (m*K), 0.8 W / (m*K), 0.9 W / (m*K), or any other value less than 1 W / (m*K), and no further examples are given here. The thermal conductivity of the outer skeleton 121 being less than 1 W / (m*K) can prevent heat from being propagated to adjacent cells 20 in a short time, causing the adjacent cells 20 to get out of control.
[0068] It can be understood that when the outer skeleton 121 includes the first outer skeleton 1211 and the second outer skeleton 1212, the thermal conductivities of both the first outer skeleton 1211 and the second outer skeleton 1212 are less than 1 W / (m*K).
[0069] In some embodiments, the ratio between the thermal conductivity of the middle skeleton 122 and the thermal conductivity of the outer skeleton 121 is greater than 100. Thus, the ability of the middle skeleton 122 to conduct heat is much stronger than that of the outer skeleton 121, which can further ensure that heat is propagated as soon as possible in the direction parallel to the cell surface 201 through the middle skeleton 122, and prevent heat from being propagated to adjacent cells 20 in a short time through the outer skeleton 121, causing the adjacent cells 20 to get out of control.
[0070] Please refer to Figure 2 , in some embodiments, the thickness of the middle skeleton 122 is greater than the thicknesses of the first outer skeleton 1211 and the second outer skeleton 1212.
[0071] That is to say, in the sandwich structure formed by the first outer skeleton 1211, the middle skeleton 122 and the second outer skeleton 1212, the middle is the thickest and the two sides are thinner.
[0072] In some embodiments, the thickness ratio of the first outer skeleton 1211 in the multi-layer skeleton 12 is 20% - 30%; and / or the thickness ratio of the second outer skeleton 1212 in the multi-layer skeleton 12 is 20% - 30%. Here, the total thickness of the multi-layer skeleton 12 is the sum of the thicknesses of each layer of the skeleton 12.
[0073] For example, the thickness ratios of both the first outer skeleton 1211 and the second outer skeleton 1212 in the multi-layer skeleton 12 are 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, or any other arbitrary value between 20% - 30%, and no further examples are given here.
[0074] It can be understood that in terms of the thickness ratio, since it is required that the inner layer has fast heat transfer, the thickness of the middle skeleton 122 should be appropriately increased so that heat can be quickly transmitted in the direction parallel to the cell surface 201. Since it is required that the outer layer has a large thermal resistance, the thickness of the outer skeleton 121 cannot be too thin. Considering the thermal resistance requirements of the inner and outer layers, the thickness ratio of the outer skeleton 121 in the multi-layer skeleton 12 is between 40% - 60%. Since the outer skeleton 121 includes the first outer skeleton 1211 and the second outer skeleton 1212, therefore, the thickness ratios of both the first outer skeleton 1211 and the second outer skeleton 1212 in the multi-layer skeleton 12 are 20% - 30%.
[0075] Please refer to Figure 2 , Figure 9 and Figure 10 , in some embodiments, both the outer skeleton 121 and the middle skeleton 122 are hollow structures. Thus, through the hollow structure design, the overall weight of the skeleton 12 can be reduced, while ensuring the structural strength of the skeleton 12 and effectively transferring heat.
[0076] In some embodiments, the structural shapes of the outer skeleton 121 and the middle skeleton 122 are different.
[0077] Specifically, in the embodiments of the present application, the structural shape of a single-layer skeleton 12 in the multi-layer skeleton 12 is not limited. For example, it can be a quadrilateral (as shown in Figure 9 ), a pentagon, a hexagon (as shown in Figure 10The outer frame 121 and the intermediate frame 122 have different structural shapes to reduce contact between the frames 12 (because the heat-absorbing material 11 is relatively soft and easily contacts when subjected to force), increase the contact thermal resistance between the frames 12, and slow down the transfer of heat in the direction perpendicular to the battery cell surface 201.
[0078] When the outer frame 121 includes a first outer frame 1211 and a second outer frame 1212, the first outer frame 1211 and the second outer frame 1212 have different structural shapes from the intermediate frame 122. For example, the first outer frame 1211 and the second outer frame 1212 both have a hexagonal structure (formed by a whole piece of material with multiple hexagonal holes), and the intermediate frame 122 has a quadrilateral structure (formed by a whole piece of material with multiple quadrilateral holes).
[0079] See also Figure 2 In some embodiments, the heat absorption unit 10 further includes a packaging shell 13 , and the heat absorption material 11 and the multi-layer skeleton 12 are both disposed in the packaging shell 13 .
[0080] Specifically, the packaging shell 13 can serve as the outer shell of the entire heat absorption unit 10 , and is used to encapsulate and protect the internal heat absorption material 11 and the multi-layer skeleton 12 , thereby ensuring the stability and durability of the heat absorption unit 10 .
[0081] See also Figure 1 The present application also provides a battery pack 100. The battery pack 100 includes a plurality of battery cells 20 and one or more heat absorbing units 10 according to any of the above embodiments. The heat absorbing unit 10 is used to absorb heat generated by the battery cells 20.
[0082] Specifically, when the battery pack 100 includes two battery cells 20, only one heat absorption unit 10 may be provided, with the heat absorption unit 10 located between the battery cell surfaces 201 of the two battery cells 20. When the battery pack 100 includes three or more battery cells 20, multiple heat absorption units 10 are required, with one heat absorption unit 10 located between the battery cell surfaces 201 of every two battery cells 20.
[0083] See also Figure 11 The embodiment of the present application further provides an electric device 1000. The electric device 1000 includes the battery pack 100 of the above embodiment.
[0084] Specifically, the electric device 1000 is, for example, a vehicle or an energy storage system. Figure 11 As shown, when the electric device 1000 is a vehicle, the electric device 1000 may further include a vehicle body 200 , and the battery pack 100 is disposed on the vehicle body 200 .
[0085] In summary, in the heat absorption unit 10, the battery pack 100, and the electrical device 1000 according to the embodiments of the present application, in the first aspect, the heat absorption material 11 can effectively absorb the heat generated by the out-of-control battery cell 20 through phase change, thereby preventing thermal diffusion. In the second aspect, adding multiple layers of the framework 12 to the heat absorption material 11 can enhance the compression resistance of the heat absorption unit 10. In the third aspect, the thermal conductivity of the outer framework 121 is less than that of the intermediate framework 122, which can reduce the high temperature in the out-of-control area and enable more heat absorption material 11 to play a role, thereby efficiently solving the problem of thermal diffusion.
[0086] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, "multiple" means two or more, unless otherwise specifically and clearly defined.
[0087] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "mount", "connect", and "couple" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.
[0088] In this application, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, or may include indirect contact between the first and second features through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is less than that of the second feature.
[0089] The above disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure of this application, components and settings of specific examples are described above. Of course, they are merely examples and are not intended to limit this application. In addition, this application may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity, and does not in itself indicate the relationship between various embodiments and / or settings discussed. In addition, this application provides examples of various specific processes and materials, but those of ordinary skill in the art can recognize the application of other processes and / or the use of other materials.
[0090] In the description of this specification, descriptions with reference to terms such as "one embodiment", "some embodiments", "illustrative embodiments", "examples", "samples", "specific examples", "some examples", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of this application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.
[0091] Although the embodiments of this application have been shown and described above, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and purposes of this application. The scope of this application is defined by the claims and their equivalents.
Claims
1. A heat absorption unit (10), characterized in that: The heat absorption unit (10) is used to be arranged between the cell surfaces (201) of two adjacent cell cells (20) in a battery pack (100), and comprises: heat absorbing material (11); and A multi-layer skeleton (12), wherein the multi-layer skeleton (12) is embedded in the heat-absorbing material (11), and the multi-layer skeleton (12) comprises an outer skeleton (121) and an intermediate skeleton (122), and the thermal conductivity of the outer skeleton (121) is smaller than the thermal conductivity of the intermediate skeleton (122).
2. The heat absorption unit (10) according to claim 1, characterized in that The multiple layers of the skeleton (12) are arranged parallel to the battery core surface (201); The outer skeleton (121) is closer to the battery core surface (201) than the middle skeleton (122).
3. The heat absorption unit (10) according to claim 1, characterized in that The outer layer skeleton (121) comprises a first outer layer skeleton (1211) and a second outer layer skeleton (1212), and the intermediate skeleton (122) is located between the first outer layer skeleton (1211) and the second outer layer skeleton (1212); The thermal conductivity coefficients of the first outer layer skeleton (1211) and the second outer layer skeleton (1212) are both smaller than the thermal conductivity coefficient of the intermediate skeleton (122).
4. The heat absorption unit (10) according to claim 3, characterized in that The multi-layer skeleton (12) further includes a transition skeleton (123), and the transition skeleton (123) includes: One or more first transition skeletons (1231) are arranged between the first outer skeleton (1211) and the intermediate skeleton (122), and the thermal conductivity coefficient of the multiple layers of the skeleton (12) tends to decrease along the direction from the intermediate skeleton (122) to the first outer skeleton (1211); and / or One or more second transition skeletons (1232) are arranged between the second outer skeleton (1212) and the intermediate skeleton (122), and the thermal conductivity coefficient of the multiple layers of the skeleton (12) tends to decrease along the direction from the intermediate skeleton (122) to the second outer skeleton (1212).
5. The heat absorption unit (10) according to claim 1, characterized in that The thermal conductivity of the intermediate skeleton (122) is greater than 100 W / (m*K).
6. The heat absorption unit (10) according to claim 1, characterized in that The thermal conductivity of the outer layer skeleton (121) is less than 1W / (m*K).
7. The heat absorption unit (10) according to claim 1, characterized in that The ratio of the thermal conductivity of the intermediate skeleton (122) to the thermal conductivity of the outer skeleton (121) is greater than 100.
8. The heat absorption unit (10) according to claim 3, characterized in that: The thickness of the intermediate skeleton (122) is greater than the thickness of the first outer skeleton (1211) and the second outer skeleton (1212).
9. The heat absorption unit (10) according to claim 3, characterized in that: The thickness of the first outer layer skeleton (1211) accounts for 20% to 30% of the multi-layer skeleton (12); and / or the thickness of the second outer layer skeleton (1212) accounts for 20% to 30% of the multi-layer skeleton (12).
10. The heat absorption unit (10) according to claim 1, characterized in that The outer layer skeleton (121) and the intermediate skeleton (122) are both hollow structures.
11. The heat absorption unit (10) according to claim 1, characterized in that The outer layer skeleton (121) and the intermediate skeleton (122) have different structural shapes.
12. The heat absorption unit (10) according to claim 1, characterized in that The heat absorption unit (10) further comprises a packaging shell (13), wherein the heat absorption material (11) and the multi-layered skeleton (12) are both arranged in the packaging shell (13).
13. A battery pack (100), characterized in that: include: a plurality of battery cells (20); and One or more heat absorption units (10) according to any one of claims 1 to 12, wherein the heat absorption unit (10) is used to absorb heat generated by the battery core (20).
14. An electrical device (1000), characterized in that: Comprising the battery pack (100) according to claim 13.