Heat insulation assembly, battery module and electrical device

Abstract

Disclosed in the present application are a heat insulation assembly, a battery module and an electrical device. The heat insulation assembly comprises a first heat absorbing layer, wherein one side of the first heat absorbing layer can fit to a battery cell, and heat generated by the battery cell can be first conducted to the side of the first heat absorbing layer close to the battery cell; the temperature of the portion of the first heat absorbing layer close to the battery cell is higher, and the temperature of the portion of the first heat absorbing layer away from the battery cell is lower; the first heat absorbing layer at least comprises a first heat absorbing sub-layer and a second heat absorbing sub-layer that are stacked; the first heat absorbing sub-layer is close to the battery cell, and the second heat absorbing sub-layer is farther from the battery cell, the thermal reaction temperature of the first heat absorbing sub-layer being higher than the thermal reaction temperature of the second heat absorbing sub-layer.

Description

Thermal insulation assembly, battery module and electric device

[0001] The present application claims priority to the Chinese patent application No. 202411076086.6, filed on August 7, 2024, entitled "Thermal insulation assembly, battery module and electric device", the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of battery, more particularly, to a thermal insulation assembly, a battery module and an electric device. BACKGROUND

[0003] The battery module is a module structure stacked by a plurality of battery cells. During the charging and discharging process, some battery cells may be in thermal runaway due to accidents. The battery cells in thermal runaway release a large amount of heat, which is further conducted to the adjacent battery cells to increase the temperature of the adjacent battery cells, thereby causing other battery cells to also be in thermal runaway, and finally leading to the explosion risk of the battery module.

[0004] At present, in order to avoid the spread of thermal runaway of the battery module, a thermal insulation layer can be arranged between the adjacent battery cells to block the heat released by the battery cells in thermal runaway. However, the thermal insulation effect of the thermal insulation layer is poor, and only part of the heat can be blocked, so that part of the heat is still conducted to the adjacent battery cells, thereby increasing the risk of spread of thermal runaway of the battery module. SUMMARY

[0005] The present application aims to provide a thermal insulation assembly, a battery module and an electric device, and solves the problem of easy spread of thermal runaway of the battery module in the related art.

[0006] In a first aspect, the present application provides a thermal insulation assembly, comprising:

[0007] a first heat absorption layer, the first heat absorption layer comprising at least a first heat absorption sub-layer and a second heat absorption sub-layer, the first heat absorption sub-layer and the second heat absorption sub-layer being arranged in a stack;

[0008] wherein the thermal reaction temperature of the first heat absorption sub-layer adjacent to the heat source is higher than the thermal reaction temperature of the second heat absorption sub-layer away from the heat source.

[0009] In some embodiments, the thermal insulation assembly further comprises a first thermal insulation layer, the first thermal insulation layer being arranged on the side of the first heat absorption sub-layer away from the second heat absorption sub-layer.

[0010] In some embodiments, the thermal insulation assembly further comprises a second heat absorption layer, the second heat absorption layer being arranged on the side of the first heat absorption layer away from the first thermal insulation layer.

[0011] The second heat-absorbing layer comprises at least a third heat-absorbing sub-layer and a fourth heat-absorbing sub-layer, the third heat-absorbing sub-layer and the fourth heat-absorbing sub-layer are stacked, the thermal reaction temperature of the third heat-absorbing sub-layer adjacent to the first heat-absorbing layer is lower than the thermal reaction temperature of the fourth heat-absorbing sub-layer away from the first heat-absorbing layer.

[0012] In some embodiments, the first heat-absorbing sub-layer away from the first heat-insulating layer and the second heat-absorbing sub-layer close to the first heat-insulating layer are an integral structure.

[0013] In some embodiments, the heat-insulating assembly further comprises a second heat-insulating layer, the second heat-insulating layer is stacked on the side of the second heat-absorbing layer away from the first heat-absorbing layer.

[0014] In some embodiments, the material of the first heat-absorbing layer is a phase change material and / or a chemical heat storage material.

[0015] The material of the second heat-absorbing layer is a phase change material and / or a chemical heat storage material.

[0016] In some embodiments, when the material of the first heat-absorbing sub-layer is a chemical heat storage material, the material of the first heat-absorbing sub-layer comprises at least one of Mg(OH)2, MgH2, Co3O4 and PbCO3.

[0017] When the material of the first heat-absorbing sub-layer is a phase change material, the material of the first heat-absorbing sub-layer comprises at least one of a mixture of Li2CO3, Na2CO3 and K2CO3, a mixture of NaCl, CaCl2 and MgCl2, a mixture of MgCl2 and NaCl, a mixture of MgCl2 and KCl, and a mixture of Li2CO3 and K2CO3.

[0018] When the material of the fourth heat-absorbing sub-layer is a chemical heat storage material, the material of the fourth heat-absorbing sub-layer comprises at least one of Mg(OH)2, MgH2, Co3O4 and PbCO3.

[0019] When the material of the fourth heat-absorbing sub-layer is a phase change material, the material of the fourth heat-absorbing sub-layer comprises at least one of a mixture of Li2CO3, Na2CO3 and K2CO3, a mixture of NaCl, CaCl2 and MgCl2, a mixture of MgCl2 and NaCl, a mixture of MgCl2 and KCl, and a mixture of Li2CO3 and K2CO3.

[0020] In some embodiments, when the material of the second heat-absorbing sub-layer is a chemical heat storage material, the material of the second heat-absorbing sub-layer comprises at least one of Ni(OH)2, NaHCO3, Al(OH)3, MgAl(OH)5 and Mg(OH)2.

[0021] When the material of the second heat-absorbing sub-layer is a phase change material, the material of the second heat-absorbing sub-layer comprises at least one of a mixture of LiNO3 and KCl, a mixture of LiNO3 and NaNO3, a mixture of KNO3 and NaNO3, a mixture of LiNO3 and NaCl, and a mixture of NaNO3 and KNO3;

[0022] When the material of the third heat-absorbing sub-layer is a chemical heat storage material, the material of the third heat-absorbing sub-layer comprises at least one of Ni(OH)2, NaHCO3, Al(OH)3, MgAl(OH)5 and Mg(OH)2;

[0023] When the material of the third heat-absorbing sub-layer is a phase change material, the material of the third heat-absorbing sub-layer comprises at least one of a mixture of LiNO3 and KCl, a mixture of LiNO3 and NaNO3, a mixture of KNO3 and NaNO3, a mixture of LiNO3 and NaCl, and a mixture of NaNO3 and KNO3.

[0024] In some embodiments, the material of the first heat-insulating layer comprises at least one of aerogel heat insulation cotton, mica sheet, vacuum heat insulation board, asbestos, glass wool, expanded perlite, slag wool and foamed ceramic;

[0025] The material of the second heat-insulating layer comprises at least one of aerogel heat insulation cotton, mica sheet, vacuum heat insulation board, asbestos, glass wool, expanded perlite, slag wool and foamed ceramic.

[0026] In some embodiments, the thickness of the first heat-insulating layer and the second heat-insulating layer is greater than or equal to 0.1 mm and less than or equal to 10 mm;

[0027] The thickness of the first heat-absorbing layer and the second heat-absorbing layer is greater than or equal to 0.01 mm and less than or equal to 10 mm.

[0028] In some embodiments, the ratio of the thickness of the first heat-absorbing sub-layer to the thickness of the second heat-absorbing sub-layer is between 1:100 and 100:1;

[0029] The ratio of the thickness of the fourth heat-absorbing sub-layer to the thickness of the third heat-absorbing sub-layer is between 1:100 and 100:1.

[0030] In a second aspect, based on the above heat-insulating assembly, the present application provides a battery module, comprising a shell, a plurality of battery cells and the above heat-insulating assembly, the plurality of battery cells are stacked in the shell along the thickness direction of the battery cells, and the heat-insulating assembly is located between adjacent battery cells.

[0031] In a third aspect, based on the battery module above, the application further provides a power consumption device comprising the battery module above.

[0032] The heat insulation assembly provided by the application can be applied to the battery module and arranged on the battery cell. One side of the first heat absorption layer can be attached to the battery cell, and the heat generated by the battery cell can be first conducted to the side of the first heat absorption layer close to the battery cell. The temperature of the part of the first heat absorption layer close to the battery cell is relatively high, and the temperature of the part of the first heat absorption layer away from the battery cell is relatively low. The first heat absorption layer at least comprises a first heat absorption sub-layer and a second heat absorption sub-layer which are superposed. The first heat absorption sub-layer is close to the battery cell, and the second heat absorption sub-layer is relatively far away from the battery cell. The thermal reaction temperature of the first heat absorption sub-layer is higher than that of the second heat absorption sub-layer, so that the first heat absorption sub-layer can first absorb part of the high heat released by the battery cell, so that the heat is reduced. The reduced heat can be absorbed by the second heat absorption sub-layer, so that the heat released by the battery cell can be fully absorbed by the heat absorption layer, avoiding the heat from being dissipated in the battery module to affect other battery cells.

[0033] The battery module provided by the application can effectively block and absorb the heat when part of the battery cells in the battery module appears thermal runaway, avoid the heat from being conducted to the adjacent battery cells, and thus effectively reduce the explosion risk of the battery module. BRIEF DESCRIPTION OF DRAWINGS

[0034] FIG. 1 is a schematic view of a battery module according to an embodiment of the application;

[0035] FIG. 2 is a schematic view of a heat insulation assembly according to an embodiment of the application;

[0036] FIG. 3 is a schematic view of a first heat absorption layer of the heat insulation assembly according to an embodiment of the application;

[0037] FIG. 4 is a schematic view of a second heat absorption layer of the heat insulation assembly according to an embodiment of the application;

[0038] FIG. 5 is a schematic view of a third heat absorption sub-layer and a fourth heat absorption sub-layer of the heat insulation assembly according to an embodiment of the application;

[0039] FIG. 6 is a schematic view of a second heat absorption sub-layer and a third heat absorption sub-layer of the heat insulation assembly according to an embodiment of the application.

[0040] Reference signs: 10-heat insulation assembly, 100-first heat insulation layer, 200-first heat absorption layer, 210-first heat absorption sub-layer, 220-second heat absorption sub-layer, 300-second heat absorption layer, 310-third heat absorption sub-layer, 320-fourth heat absorption sub-layer, 400-second heat insulation layer, 500-battery cell, 600-housing. DETAILED DESCRIPTION

[0041] Embodiments of the present application are described below in detail with reference to examples shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary only, and are for the purpose of explanation only, and are not to be understood as limiting the present application.

[0042] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0043] The battery module is a module structure stacked by a plurality of battery cells. During charging and discharging, some battery cells may be accidentally overheated. The overheated battery cells release a large amount of heat, which is further conducted to adjacent battery cells to increase the temperature of the adjacent battery cells, thereby causing other battery cells to also overheat, and eventually leading to an explosion risk of the battery module.

[0044] Currently, in order to avoid the spread of overheating in the battery module, a heat insulation layer can be arranged between adjacent battery cells to block the heat released by the overheated battery cells. However, the heat insulation effect of the heat insulation layer is not good. In order to make the heat insulation layer have good heat insulation effect, the thickness of the heat insulation layer needs to be relatively thick. This will correspondingly cause the heat insulation layer to occupy too much space in the battery module, thereby reducing the space available for arranging the battery cells, and eventually reducing the energy density of the battery module.

[0045] The heat insulation assembly provided in the present application can be applied to the battery module and arranged on the battery cells. One side of the first heat absorption layer can be attached to the battery cells, and the heat generated by the battery cells can be first conducted to the side of the first heat absorption layer close to the battery cells. The temperature of the part of the first heat absorption layer close to the battery cells is relatively high, and the temperature of the part of the first heat absorption layer away from the battery cells is relatively low. The first heat absorption layer at least includes a first heat absorption sub-layer and a second heat absorption sub-layer stacked with each other. The first heat absorption sub-layer is close to the battery cells, and the second heat absorption sub-layer is relatively far away from the battery cells. The thermal reaction temperature of the first heat absorption sub-layer is higher than that of the second heat absorption sub-layer, so that the first heat absorption sub-layer can first absorb part of the high heat released by the battery cells, so that the heat is reduced. The reduced heat can be absorbed by the second heat absorption sub-layer, so that the heat released by the battery cells can be fully absorbed by the heat absorption layer, avoiding the heat spreading in the battery module to affect other battery cells.

[0046] The battery module provided in the application can effectively block and absorb heat when part of the battery cells in the battery module appears thermal runaway, avoid heat conduction to adjacent battery cells, and thus effectively reduce the explosion risk of the battery module.

[0047] The heat insulation assembly, the battery module and the electric equipment provided in the application will be described in detail below in combination with specific embodiments.

[0048] The embodiment of the application provides a battery module, as shown in FIG. 1, which comprises a shell 600, a plurality of battery cells 500 and a heat insulation assembly.

[0049] The shell 600 is the basic component of the battery module of the application. The shell 600 can provide a mounting base for other at least partial components of the battery module and serve the purpose of protecting the other at least partial components. The shell 600 can be made of metal material, so that the shell 600 has better structural strength, thereby making the durability and reliability of the shell 600 better. Of course, the shell 600 can also be made of composite material, so that the shell 600 has a certain structural strength while being relatively light in weight.

[0050] The plurality of battery cells 500 can be stacked in the thickness direction of the battery cells 500 in the shell 600, that is, in the X direction in FIG. 1, and the plurality of battery cells 500 are electrically connected, so that the plurality of battery cells 500 can output electric energy at the same time. The plurality of battery cells 500 are stacked in the thickness direction of the battery cells 500, which can make the structure of the battery module relatively more compact. The heat insulation assembly is arranged between adjacent battery cells 500. When part of the battery cells 500 of the battery module appears thermal runaway condition and releases heat, the heat insulation assembly can be used to block the heat released by the battery cells 500, so as to reduce the heat conduction to the adjacent battery cells 500, avoid the temperature of the battery cells 500 adjacent to the battery cells 500 with thermal runaway being too high, and thus avoid the condition of thermal runaway spreading of the battery module.

[0051] In order to make the safety and reliability of the battery module of the application better, as shown in FIGS. 2 and 3, the embodiment of the application further provides a heat insulation assembly 10 comprising a first heat absorption layer 200. The heat insulation assembly 10 can be applied to the battery module of the application, and the heat insulation assembly is arranged between adjacent battery cells 500.

[0052] The first heat absorption layer 200 in the present application can be provided with at least a first heat absorption sub-layer 210 and a second heat absorption sub-layer 220, the first heat absorption sub-layer 210 is stacked on the first heat insulation layer 100, the second heat absorption sub-layer 220 is stacked on the battery cell 500, and the second heat absorption sub-layer 220 is located on the side of the first heat absorption sub-layer 210 away from the battery cell 500. The thermal reaction temperature of the first heat absorption sub-layer 210 is higher than that of the second heat absorption sub-layer 220. Among them, the first heat absorption sub-layer 210 is stacked on the battery cell 500, so that the first heat absorption sub-layer 210 can be attached to the battery cell 500, and the second heat absorption sub-layer 220 is stacked on the side of the first heat absorption sub-layer 210 away from the battery cell 500, so that the first heat absorption sub-layer 210 is closer to the battery cell 500 than the second heat absorption sub-layer 220, and the second heat absorption sub-layer 220 is farther away from the battery cell 500 than the first heat absorption sub-layer 210.

[0053] The thermal reaction temperature of the first heat absorption sub-layer 210 is higher than that of the second heat absorption sub-layer 220, when the thermal runaway battery cell 500 releases heat, the heat is first conducted to the first heat absorption sub-layer 210, and correspondingly, the heat conducted to the first heat absorption sub-layer 210 is more sufficient, so that the first heat absorption sub-layer 210 is heated more fully by the heat released by the thermal runaway battery cell 500, and the temperature is higher, and the first heat absorption sub-layer 210 can absorb higher heat. The relatively high thermal reaction temperature of the first heat absorption sub-layer 210 can make the first heat absorption sub-layer 210 fully absorb higher heat. After the heat is absorbed by the first heat absorption sub-layer 210, the remaining heat is low, and the remaining heat is conducted to the second heat absorption sub-layer 220, and the thermal reaction temperature of the second heat absorption sub-layer 220 is low, so that the second heat absorption sub-layer 220 can fully absorb lower heat, so that the heat released by the thermal runaway battery cell 500 can be fully absorbed.

[0054] In addition, the first heat absorption layer 200 can also be provided with a larger number of heat absorption sub-layers, for example, one heat absorption sub-layer is stacked on the side of the second heat absorption sub-layer 220 away from the first heat absorption sub-layer 210, and the thermal reaction temperature of the heat absorption sub-layer is lower than that of the second heat absorption sub-layer 220. Thus, the multiple heat absorption sub-layers in the first heat absorption layer 200 can sequentially absorb gradually reduced heat, so that the first heat absorption layer 200 has better heat absorption effect.

[0055] In some embodiments, referring to FIG. 2, the thermal insulation assembly 10 of the present application can further comprise a first thermal insulation layer 100. The first thermal insulation layer 100 is a basic component of the thermal insulation assembly of the present application, and can provide a mounting base for other components of the thermal insulation assembly. The first thermal insulation layer 100 is made of a thermal insulation material, so that the first thermal insulation layer 100 can block heat. The first thermal insulation layer 100 can be arranged in close contact with the battery cell 500, specifically in close contact with the large face of the battery cell 500. When the battery cell 500 is in a thermal runaway state and releases heat, the heat will first be blocked by the first thermal insulation layer 100, so that the heat conducted to the adjacent battery cell 500 through the first thermal insulation layer 100 is reduced to a certain extent. The first heat absorption layer 200 is stacked on the first thermal insulation layer 100 and located on the side of the first thermal insulation layer 100 away from the battery cell 500. Specifically, the stacking direction of the first heat absorption layer 200 and the first thermal insulation layer 100 is the thickness direction of the battery cell 500, i.e., the X direction in FIG. 2. Accordingly, the part of the heat released by the battery cell 500 in a thermal runaway state and not blocked by the first thermal insulation layer 100 can be conducted to the first heat absorption layer 200. The first heat absorption layer 200 is made of a heat absorption material, so that the first heat absorption layer 200 can absorb the heat released by the battery cell 500 in a thermal runaway state, thereby reducing the heat conducted from the battery cell 500 in a thermal runaway state to the adjacent battery cell 500.

[0056] Therefore, when part of the battery cells 500 in the battery module are in a thermal runaway state and release heat, part of the heat can be blocked by the first thermal insulation layer 100, and another part of the heat can be gradually absorbed by the first heat absorption layer 200, so that the heat finally conducted to the adjacent battery cell 500 is low, thereby avoiding the adjacent battery cell 500 from being in a thermal runaway state due to high temperature, effectively preventing the probability of the battery module from being in a thermal runaway spreading state, and improving the safety and reliability of the battery module.

[0057] In some embodiments, referring to FIG. 4, the thermal insulation assembly of the present application can further comprise a second heat absorption layer 300, which is stacked on the side of the first heat absorption layer 200 away from the first thermal insulation layer 100. In the direction away from the first thermal insulation layer 100, the thermal reaction temperature of the second heat absorption layer 300 increases, so that the thermal reaction temperature of the side of the second heat absorption layer 300 away from the first heat absorption layer 200 is higher than the thermal reaction temperature of the side of the second heat absorption layer 300 close to the first heat absorption layer 200. Since the thermal insulation assembly can be arranged between adjacent battery cells 500 in the battery module, and the second heat absorption layer 300 is stacked on the side of the first heat absorption layer 200 away from the first thermal insulation layer 100, the first thermal insulation layer 100 is in close contact with one of the two adjacent battery cells 500, and the side of the second heat absorption layer 300 away from the first heat absorption layer 200 can be in close contact with the other of the two adjacent battery cells 500.

[0058] Thus, when the other one of the two adjacent battery cells 500 releases heat due to thermal runaway, the released heat can be conducted to the second heat absorption layer 300, and the heat reaction temperature of the side of the second heat absorption layer 300 away from the first heat absorption layer 200 is relatively high, so that the second heat absorption layer 300 can absorb relatively high heat. The remaining heat after the side of the second heat absorption layer 300 away from the first heat absorption layer 200 absorbs heat is conducted to the side of the second heat absorption layer 300 close to the first heat absorption layer 200, and the side of the second heat absorption layer 300 close to the first heat absorption layer 200 can reduce the absorption of the remaining heat, so that the heat released by the other one of the two adjacent battery cells 500 due to thermal runaway can also be effectively absorbed. Thus, when the two adjacent battery cells 500 in the battery module are in thermal runaway, the heat can be fully and effectively absorbed by the heat insulation assembly, further improving the anti-thermal runaway spreading performance of the battery module, and making the safety and reliability of the battery module better.

[0059] In some embodiments, referring to FIG. 5, the second heat absorption layer 300 in the present application can be provided to include a third heat absorption sub-layer 310 and a fourth heat absorption sub-layer 320. The third heat absorption sub-layer 310 is stacked on the side of the second heat absorption sub-layer 220 away from the first heat absorption sub-layer 210, and the fourth heat absorption sub-layer 320 is stacked on the side of the third heat absorption sub-layer 310 away from the second heat absorption sub-layer 220. The heat reaction temperature of the third heat absorption sub-layer 310 is lower than that of the fourth heat absorption sub-layer 320. Correspondingly, the third heat absorption sub-layer 310 is stacked on the side of the fourth heat absorption sub-layer 320 away from the battery cell 500, so that the fourth heat absorption sub-layer 320 is closer to the battery cell 500 than the third heat absorption sub-layer 310, and the third heat absorption sub-layer 310 is farther away from the battery cell 500 than the fourth heat absorption sub-layer 320.

[0060] When the battery cell 500 in thermal runaway releases heat, the heat is first conducted to the fourth heat absorption sub-layer 320. Correspondingly, the heat conducted to the fourth heat absorption sub-layer 320 is more sufficient, so that the fourth heat absorption sub-layer 320 is heated more sufficiently by the heat released by the battery cell 500 in thermal runaway, and the temperature is higher. The fourth heat absorption sub-layer 320 can absorb relatively high heat. The heat reaction temperature of the fourth heat absorption sub-layer 320 is relatively high, so that the fourth heat absorption sub-layer 320 can fully absorb relatively high heat. The remaining heat after the heat is absorbed by the fourth heat absorption sub-layer 320 is relatively low, and the remaining heat is conducted to the third heat absorption sub-layer 310. The heat reaction temperature of the third heat absorption sub-layer 310 is relatively low, so that the third heat absorption sub-layer 310 can fully absorb relatively low heat, so that the heat released by the battery cell 500 in thermal runaway can be fully absorbed.

[0061] In addition, the second heat absorption layer 300 can further include a plurality of heat absorption sub-layers. For example, one heat absorption sub-layer is further stacked on the side of the third heat absorption sub-layer 310 away from the fourth heat absorption sub-layer 320, and the heat reaction temperature of the heat absorption sub-layer is lower than that of the third heat absorption sub-layer 310. In this way, the plurality of heat absorption sub-layers in the second heat absorption layer 300 can sequentially absorb heat in a gradually decreasing manner, so that the second heat absorption layer 300 has a better heat absorption effect.

[0062] In some embodiments, referring to FIG. 5, the heat insulation assembly of the present application can further include a second heat insulation layer 400, which is stacked on the side of the second heat absorption layer 300 away from the first heat absorption layer 200. Specifically, the second heat insulation layer 400 is stacked on the side of the fourth heat absorption sub-layer 320 away from the third heat absorption sub-layer 310, and the side of the second heat insulation layer 400 away from the fourth heat absorption sub-layer 320 can be attached to the other one of the two adjacent battery cells 500. The second heat insulation layer 400 is made of a heat insulation material. When the other one of the two adjacent battery cells 500 releases heat due to thermal runaway, the heat is first blocked by the second heat insulation layer 400, and the remaining heat is then conducted to the fourth heat absorption sub-layer, thereby further reducing the amount of heat conduction between the two adjacent battery cells 500.

[0063] In some embodiments, referring to FIG. 6, the second heat absorption sub-layer 220 and the third heat absorption sub-layer 310 of the present application can be configured as an integrated structure, i.e., the second heat absorption sub-layer 220 and the third heat absorption sub-layer 310 are connected as an integrated structure and can be integrally formed. When the heat insulation assembly of the present application is prepared, the second heat absorption sub-layer 220 and the third heat absorption sub-layer 310 are integrally formed, and then the first heat absorption sub-layer 210 and the fourth heat absorption sub-layer 320 are stacked on the two sides of the integrated structure of the second heat absorption sub-layer 220 and the third heat absorption sub-layer 310, respectively. Then, the first heat insulation layer 100 is stacked on the first heat absorption sub-layer 210, and the second heat insulation layer 400 is stacked on the fourth heat absorption sub-layer 320. In this way, the second heat absorption sub-layer 220 and the third heat absorption sub-layer 310 do not need to be prepared separately, so that the preparation process of the heat insulation assembly is simpler and the structure is more compact.

[0064] In some embodiments, in order to enable the first heat absorption layer 200 and the second heat absorption layer 300 to absorb heat, the material of the first heat absorption layer 200 can be a phase change material and / or a chemical heat storage material, and the material of the second heat absorption layer 300 can also be a phase change material and / or a chemical heat storage material. The phase change material can absorb heat through a physical reaction, and the chemical heat storage material can absorb heat through a chemical reaction, so that the first heat absorption layer 200 and the second heat absorption layer 300 can both absorb heat.

[0065] Specifically, the first heat absorbing layer 200 can adopt a phase change material, a chemical material, or a part of the first heat absorbing layer 200 adopts a phase change material and another part of the first heat absorbing layer 200 adopts a chemical heat storage material. The second heat absorbing layer 300 can adopt a phase change material, a chemical material, or a part of the first heat absorbing layer 200 adopts a phase change material and another part of the first heat absorbing layer 200 adopts a chemical heat storage material.

[0066] In some embodiments, the first heat absorbing sub-layer 210 of the first heat absorbing layer 200 in the present application can be made of a phase change material or a chemical heat storage material. When the first heat absorbing sub-layer 210 is made of a chemical heat storage material, the material of the first heat absorbing sub-layer 210 includes at least one of Mg(OH)2, MgH2, Co3O4, and PbCO3. That is, the first heat absorbing sub-layer 210 can be made of any single material among the above-mentioned chemical heat storage materials, or made of a mixture of multiple materials among the above-mentioned chemical heat storage materials, so that the first heat absorbing sub-layer 210 can absorb heat and the heat reaction temperature of the first heat absorbing sub-layer 210 is relatively high.

[0067] When the first heat absorbing sub-layer 210 is made of a phase change material, the material of the first heat absorbing sub-layer 210 includes at least one of a mixture of Li2CO3, Na2CO3, and K2CO3, a mixture of NaCl, CaCl2, and MgCl2, a mixture of MgCl2 and NaCl, a mixture of MgCl2 and KCl, and a mixture of Li2CO3 and K2CO3. In this way, the first heat absorbing sub-layer 210 can absorb heat and the heat reaction temperature of the first heat absorbing sub-layer 210 is relatively high.

[0068] The fourth heat absorbing sub-layer 320 of the second heat absorbing layer 300 in the present application can be made of a phase change material or a chemical heat storage material. When the fourth heat absorbing sub-layer 320 is made of a chemical heat storage material, the material of the fourth heat absorbing sub-layer 320 includes at least one of Mg(OH)2, MgH2, Co3O4, and PbCO3. That is, the fourth heat absorbing sub-layer 320 can be made of any single material among the above-mentioned chemical heat storage materials, or made of a mixture of multiple materials among the above-mentioned chemical heat storage materials, so that the fourth heat absorbing sub-layer 320 can absorb heat and the heat reaction temperature of the fourth heat absorbing sub-layer 320 is relatively high.

[0069] When the fourth heat-absorbing sub-layer 320 is made of a phase change material, the material of the fourth heat-absorbing sub-layer 320 includes at least one of a mixture of Li2CO3, Na2CO3 and K2CO3, a mixture of NaCl, CaCl2 and MgCl2, a mixture of MgCl2 and NaCl, a mixture of MgCl2 and KCl, and a mixture of Li2CO3 and K2CO3. This allows the fourth heat-absorbing sub-layer 320 to absorb heat and have a relatively high thermal reaction temperature.

[0070] In some embodiments, the second heat-absorbing sub-layer 220 of the first heat-absorbing layer 200 can be made of a phase change material or a chemical heat storage material. When the second heat-absorbing sub-layer 220 is made of a chemical heat storage material, the material of the second heat-absorbing sub-layer 220 includes at least one of Ni(OH)2, NaHCO3, Al(OH)3, MgAl(OH)5 and Mg(OH)2. That is, the second heat-absorbing sub-layer 220 can be made of any single material among the above-mentioned chemical heat storage materials or a mixture of multiple materials among the above-mentioned chemical heat storage materials. This allows the second heat-absorbing sub-layer 220 to absorb heat and have a thermal reaction temperature lower than that of the first heat-absorbing sub-layer 210.

[0071] When the second heat-absorbing sub-layer 220 is made of a phase change material, the material of the second heat-absorbing sub-layer 220 includes at least one of a mixture of LiNO3 and KCl, a mixture of LiNO3 and NaNO3, a mixture of KNO3 and NaNO3, a mixture of LiNO3 and NaCl, and a mixture of NaNO3 and KNO3. This allows the second heat-absorbing sub-layer 220 to absorb heat and have a thermal reaction temperature lower than that of the first heat-absorbing sub-layer 210.

[0072] The third heat-absorbing sub-layer 310 of the second heat-absorbing layer 300 can be made of a phase change material or a chemical heat storage material. When the third heat-absorbing sub-layer 310 is made of a chemical heat storage material, the material of the third heat-absorbing sub-layer 310 includes at least one of Ni(OH)2, NaHCO3, Al(OH)3, MgAl(OH)5 and Mg(OH)2. That is, the third heat-absorbing sub-layer 310 can be made of any single material among the above-mentioned chemical heat storage materials or a mixture of multiple materials among the above-mentioned chemical heat storage materials. This allows the third heat-absorbing sub-layer 310 to absorb heat and have a thermal reaction temperature lower than that of the fourth heat-absorbing sub-layer 320.

[0073] When the third heat-absorbing sub-layer 310 adopts a phase change material, the material of the third heat-absorbing sub-layer 310 includes at least one of a mixture of LiNO3 and KCl, a mixture of LiNO3 and NaNO3, a mixture of KNO3 and NaNO3, a mixture of LiNO3 and NaCl, and a mixture of NaNO3 and KNO3. In this way, the third heat-absorbing sub-layer 310 can absorb heat, and the thermal reaction temperature of the third heat-absorbing sub-layer 310 is lower than the thermal reaction temperature of the fourth heat-absorbing sub-layer 320.

[0074] In some embodiments, in order to enable the first heat-insulating layer 100 to block the heat released by the thermal runaway battery cell 500, the material of the first heat-insulating layer 100 can include at least one of aerogel insulation cotton, mica sheet, vacuum insulation board, asbestos, glass wool, expanded perlite, slag wool, and foamed ceramic. That is, the first heat-insulating layer 100 can be prepared by using any single material among the above-mentioned materials or by using a mixture of multiple materials among the above-mentioned materials, so that the first heat-insulating layer 100 has good heat-insulating performance.

[0075] In order to enable the second heat-insulating layer 400 to block the heat released by the thermal runaway battery cell 500, the material of the second heat-insulating layer 400 can include at least one of aerogel insulation cotton, mica sheet, vacuum insulation board, asbestos, glass wool, expanded perlite, slag wool, and foamed ceramic. That is, the second heat-insulating layer 400 can be prepared by using any single material among the above-mentioned materials or by using a mixture of multiple materials among the above-mentioned materials, so that the second heat-insulating layer 400 has good heat-insulating performance.

[0076] In some embodiments, the thickness of the first heat-absorbing layer 200 can be greater than or equal to 0.01 mm and less than or equal to 10 mm, and the thickness of the second heat-absorbing layer 300 can also be greater than or equal to 0.01 mm and less than or equal to 10 mm.

[0077] The thickness of the first heat-insulating layer 100 can be greater than or equal to 0.1 mm and less than or equal to 10 mm, and the thickness of the second heat-insulating layer 400 can also be greater than or equal to 0.1 mm and less than or equal to 10 mm.

[0078] In this way, the heat-insulating assembly of the present application can have good heat-insulating performance and a relatively compact structure, so that the space occupied by the heat-insulating assembly in the shell 600 of the battery module can be reduced, the space for installing the battery cell 500 in the shell 600 can be increased, and the electrical energy of the battery module can be more sufficient.

[0079] In some embodiments, the ratio of the thickness dimension of the first heat-absorbing sub-layer 210 to the thickness dimension of the second heat-absorbing sub-layer 220 is between 1:100 and 100:1. The ratio of the thickness dimension of the fourth heat-absorbing sub-layer 320 to the thickness dimension of the third heat-absorbing sub-layer 310 is between 1:100 and 100:1.

[0080] Next, the heat insulation performance of the heat insulation assembly of the present application is further described through three groups of experiments.

[0081] In Experiment 1, the thickness dimension of the first heat insulation layer 100 and the second heat insulation layer 400 of the heat insulation assembly is set to 1 mm, the thickness of the first heat-absorbing sub-layer 210 is 0.3 mm, the sum of the thicknesses of the one-piece structure of the second heat-absorbing sub-layer 220 and the third heat-absorbing sub-layer 310 is 0.4 mm, and the thickness of the fourth heat-absorbing sub-layer 320 is 0.3 mm. The main material of the first heat-absorbing sub-layer 210, the second heat-absorbing sub-layer 220, the third heat-absorbing sub-layer 310, and the fourth heat-absorbing sub-layer 320 is Mg(OH)2, and the additive is epoxy resin, wherein the epoxy resin can shape the powdered Mg(OH)2. The material of the first heat insulation layer 100 and the second heat insulation layer 400 is silica aerogel heat insulation cotton of glass fiber material.

[0082] The heat insulation assembly is installed between adjacent battery cells 500 of a battery module, and after a certain battery cell 500 releases heat by overcharging to cause thermal runaway, the temperature of the battery cell 500 and the temperatures of other battery cells 500 are detected. The maximum temperature of the battery cell 500 in thermal runaway is 562℃, and the battery cell 500 in thermal runaway does not catch fire and explode. The maximum temperature of the battery cell 500 adjacent to the battery cell 500 in thermal runaway is 186℃, and the adjacent battery cell 500 does not trigger a thermal runaway condition. Other battery cells 500 in the battery module that are not adjacent to the battery cell 500 in thermal runaway remain at room temperature, and the battery module does not exhibit thermal runaway spreading.

[0083] In Experiment 2, the thickness dimension of the first heat insulation layer 100 and the second heat insulation layer 400 of the heat insulation assembly is set to 1 mm, the thickness of the first heat-absorbing sub-layer 210 is 0.4 mm, the sum of the thicknesses of the one-piece structure of the second heat-absorbing sub-layer 220 and the third heat-absorbing sub-layer 310 is 0.2 mm, and the thickness of the fourth heat-absorbing sub-layer 320 is 0.4 mm. The main material of the first heat-absorbing sub-layer 210 and the fourth heat-absorbing sub-layer 320 is Mg(OH)2, and the additive is epoxy resin, wherein the epoxy resin can shape the powdered Mg(OH)2. The main material of the second heat-absorbing sub-layer 220 and the third heat-absorbing sub-layer 310 is NaHCO3, and the additive is epoxy resin. The material of the first heat insulation layer 100 and the second heat insulation layer 400 is silica aerogel heat insulation cotton of glass fiber material.

[0084] The thermal insulation assembly is installed between adjacent battery cells 500 of a battery module. After a certain battery cell 500 is overcharged to release heat and cause thermal runaway, the temperature of the battery cell 500 and the temperatures of other battery cells 500 are detected. The maximum temperature of the battery cell 500 in thermal runaway is 558°C, and the battery cell 500 in thermal runaway does not catch fire or explode. The maximum temperature of the battery cell 500 adjacent to the battery cell 500 in thermal runaway is 238°C, and the adjacent battery cell 500 does not trigger a thermal runaway condition. Other battery cells 500 in the battery module that are not adjacent to the battery cell 500 in thermal runaway remain at room temperature, and the battery module does not have a thermal runaway spread condition.

[0085] In Experiment 3, the thickness of the first thermal insulation layer 100 and the second thermal insulation layer 400 of the thermal insulation assembly is 1 mm, the thickness of the first endothermic sub-layer 210 is 0.3 mm, the sum of the thicknesses of the one-piece structure of the second endothermic sub-layer 220 and the third endothermic sub-layer 310 is 0.4 mm, and the thickness of the fourth endothermic sub-layer 320 is 0.3 mm. The main material of the first endothermic sub-layer 210 and the fourth endothermic sub-layer 320 is MgH2, and the additive is epoxy resin, which can shape the powdered Mg(OH)2. The main material of the second endothermic sub-layer 220 and the third endothermic sub-layer 310 is Al(OH)3, and the additive is epoxy resin. The materials of the first thermal insulation layer 100 and the second thermal insulation layer 400 are silica aerogel thermal insulation cotton with glass fiber material.

[0086] The thermal insulation assembly is installed between adjacent battery cells 500 of a battery module. After a certain battery cell 500 is overcharged to release heat and cause thermal runaway, the temperature of the battery cell 500 and the temperatures of other battery cells 500 are detected. The maximum temperature of the battery cell 500 in thermal runaway is 545°C, and the battery cell 500 in thermal runaway does not catch fire or explode. The maximum temperature of the battery cell 500 adjacent to the battery cell 500 in thermal runaway is 213°C, and the adjacent battery cell 500 does not trigger a thermal runaway condition. Other battery cells 500 in the battery module that are not adjacent to the battery cell 500 in thermal runaway remain at room temperature, and the battery module does not have a thermal runaway spread condition.

[0087] In the control experiment, the thermal insulation assembly does not have a first endothermic layer 200 and a second endothermic layer 300, but only has a thermal insulation layer. The material of the thermal insulation layer is silica aerogel thermal insulation cotton with glass fiber material, and the thickness of the thermal insulation layer is 3 mm.

[0088] The thermal insulation assembly is installed between adjacent battery cells of a battery module. After a certain battery cell releases heat by overcharging and thermal runaway, the temperature of the battery cell and the temperature of other battery cells are detected. The maximum temperature of the battery cell with thermal runaway is 550℃, and the battery cell with thermal runaway does not catch fire and explode. The maximum temperature of the battery cell adjacent to the battery cell with thermal runaway is 286℃, and the adjacent battery cell also has thermal runaway. The temperature of other battery cells in the battery module that are not adjacent to the battery cell with thermal runaway also rises, and the battery module has thermal runaway spreading.

[0089] Therefore, the thermal insulation assembly of the present application can effectively absorb the heat released by the battery cell with thermal runaway 500 by setting the first heat absorption layer 200 and the second heat absorption layer 300, reduce the heat conduction to the adjacent battery cell 500, and make the safety and reliability of the battery module better.

[0090] The present application also provides a battery module. The battery module includes the thermal insulation assembly described above.

[0091] In the description of the present application, the description of the terms "embodiment", "example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0092] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A thermal insulation assembly (10), wherein, Comprise: A first heat absorption layer (200) comprising at least a first heat absorption sub-layer (210) and a second heat absorption sub-layer (220), the first heat absorption sub-layer (210) and the second heat absorption sub-layer (220) are stacked; Wherein, the thermal reaction temperature of the first heat absorption sub-layer (210) adjacent to the battery is higher than that of the second heat absorption sub-layer (220) away from the battery, so that the heat absorption capacity of the first heat absorption sub-layer (210) is greater than that of the second heat absorption sub-layer (220).

2. The thermally insulating assembly (10) according to claim 1, wherein The heat insulation assembly (10) further comprises a first heat insulation layer (100), the first heat insulation layer (100) is stacked on the side of the first heat absorption sub-layer (210) away from the second heat absorption sub-layer (220).

3. The thermally insulating assembly (10) according to claim 2, wherein The heat insulation assembly (10) further comprises a second heat absorption layer (300), the second heat absorption layer (300) is stacked on the side of the first heat absorption layer (200) away from the first heat insulation layer (100); The second heat absorption layer (300) comprises at least a third heat absorption sub-layer (310) and a fourth heat absorption sub-layer (320), the third heat absorption sub-layer (310) and the fourth heat absorption sub-layer (320) are stacked, the thermal reaction temperature of the third heat absorption sub-layer (310) adjacent to the first heat absorption layer (200) is lower than that of the fourth heat absorption sub-layer (320) away from the first heat absorption layer (200).

4. The thermally insulating assembly (10) according to claim 3, wherein The first heat absorption sub-layer (210) away from the first heat insulation layer (100) and the second heat absorption sub-layer (220) close to the first heat insulation layer (100) are an integral structure.

5. A thermal insulation assembly (10) according to claim 3 or 4, wherein The heat insulation assembly (10) further comprises a second heat insulation layer (400), the second heat insulation layer (400) is stacked on the side of the second heat absorption layer (300) away from the first heat absorption layer (200).

6. The thermal insulation assembly (10) according to any one of claims 3-5, wherein The material of the first heat absorption layer (200) is a phase change material and / or a chemical heat storage material; The material of the second heat absorption layer (300) is a phase change material and / or a chemical heat storage material.

7. The thermally insulating assembly (10) according to claim 6, wherein When the material of the first heat absorption sub-layer (210) is a chemical heat storage material, the material of the first heat absorption sub-layer (210) comprises at least one of Mg(OH)2, MgH2, Co3O4 and PbCO3; When the material of the first heat absorption sub-layer (210) is a phase change material, the material of the first heat absorption sub-layer (210) comprises at least one of a mixture of Li2CO3, Na2CO3 and K2CO3, a mixture of NaCl, CaCl2 and MgCl2, a mixture of MgCl2 and NaCl, a mixture of MgCl2 and KCl, and a mixture of Li2CO3 and K2CO3; When the material of the fourth heat absorption sub-layer (320) is a chemical heat storage material, the material of the fourth heat absorption sub-layer (320) comprises at least one of Mg(OH)2, MgH2, Co3O4 and PbCO3; When the material of the fourth heat-absorbing sub-layer (320) is a phase change material, the material of the fourth heat-absorbing sub-layer (320) includes at least one of a mixture of Li2CO3, Na2CO3 and K2CO3, a mixture of NaCl, CaCl2 and MgCl2, a mixture of MgCl2 and NaCl, a mixture of MgCl2 and KCl, and a mixture of Li2CO3 and K2CO3.

8. A thermal insulation assembly (10) according to claim 6 or 7, wherein When the material of the second heat-absorbing sub-layer (220) is a chemical heat storage material, the material of the second heat-absorbing sub-layer (220) includes at least one of Ni(OH)2, NaHCO3, Al(OH)3, MgAl(OH)5 and Mg(OH)2; When the material of the second heat-absorbing sub-layer (220) is a phase change material, the material of the second heat-absorbing sub-layer (220) includes at least one of a mixture of LiNO3 and KCl, a mixture of LiNO3 and NaNO3, a mixture of KNO3 and NaNO3, a mixture of LiNO3 and NaCl, and a mixture of NaNO3 and KNO3; When the material of the third heat-absorbing sub-layer (310) is a chemical heat storage material, the material of the third heat-absorbing sub-layer (310) includes at least one of Ni(OH)2, NaHCO3, Al(OH)3, MgAl(OH)5 and Mg(OH)2; When the material of the third heat-absorbing sub-layer (310) is a phase change material, the material of the third heat-absorbing sub-layer (310) includes at least one of a mixture of LiNO3 and KCl, a mixture of LiNO3 and NaNO3, a mixture of KNO3 and NaNO3, a mixture of LiNO3 and NaCl, and a mixture of NaNO3 and KNO3.

9. The thermally insulating assembly (10) according to claim 5, wherein The material of the first heat-insulating layer (100) includes at least one of aerogel heat insulation cotton, mica sheet, vacuum heat insulation board, asbestos, glass wool, expanded perlite, slag wool and foamed ceramic; The material of the second heat-insulating layer (400) includes at least one of aerogel heat insulation cotton, mica sheet, vacuum heat insulation board, asbestos, glass wool, expanded perlite, slag wool and foamed ceramic.

10. The thermally insulating assembly (10) according to claim 5, wherein, The thickness of the first heat-insulating layer (100) and the second heat-insulating layer (400) is greater than or equal to 0.1 mm and less than or equal to 10 mm; The thickness of the first heat-absorbing layer (200) and the second heat-absorbing layer (300) is greater than or equal to 0.01 mm and less than or equal to 10 mm.

11. The thermal insulation assembly (10) according to any of claims 3-10, wherein The ratio of the thickness of the first heat-absorbing sub-layer (210) to the thickness of the second heat-absorbing sub-layer (220) is between 1:100 and 100:1; The ratio of the thickness of the fourth heat-absorbing sub-layer (320) to the thickness of the third heat-absorbing sub-layer (310) is between 1:100 and 100:

1.

12. A battery module, wherein, The battery module comprises a shell (600), a plurality of battery cells (500), and the thermal insulation assembly (10) according to any one of claims 1-11, the plurality of battery cells (500) are stacked in the shell (600) along the thickness direction of the battery cells (500), and the thermal insulation assembly (10) is located between adjacent battery cells (500).

13. An electrical device, comprising: The battery module comprises the battery module according to claim 12.

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