Buffer heat insulation assembly and battery pack

Abstract

The buffer heat insulation assembly is arranged between large surfaces of two batteries in the battery pack, the buffer heat insulation assembly comprises a heat insulation layer, heat conduction layers and phase change heat absorption layers, the two heat conduction layers are arranged on the two opposite sides of the heat insulation layer respectively, and the two phase change heat absorption layers are arranged on the sides, away from the heat insulation layer, of the heat conduction layers respectively. The outer surface of the phase change heat absorption layer is wrapped with a packaging film for packaging the phase change heat absorption layer; when the temperature in the battery pack exceeds the phase change temperature of the phase change heat absorption layer, the phase change heat absorption layer is converted from a solid state to a gas state; and when the temperature in the battery pack exceeds the melting temperature of the packaging film, the packaging film is melted and gas in the packaging film is released so as to inhibit thermal runaway of the battery pack. The requirements of heat dissipation and heat insulation of the battery pack are met through the heat conduction layer and the heat insulation layer, heat management in the battery pack is realized through phase change heat absorption of the phase change heat absorption layer, and thermal runaway in the battery pack is inhibited through inert gas generated by combustion of the packaging film.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially is related to a buffer heat insulation subassembly and battery pack. BACKGROUND

[0002] In the battery pack fast charging technology, the higher charging current intensity significantly aggravates the violent degree of the oxidation-reduction reaction in the positive and negative materials of the battery cell, and this effect directly promotes the rapid rise of the temperature inside the battery pack. In this process, the excessive heat generated cannot be removed in time and fully through the effective flow of the cooling liquid in the liquid cooling system. In addition, thermal runaway refers to the exothermic chain reaction occurring inside the battery monomer, which leads to a sharp and uncontrollable rise in battery temperature, accompanied by the release of a large amount of heat. In view of this phenomenon, the current preventive measures mainly rely on deploying low thermal conductivity silicon foam or aerogel as a heat insulation pad between adjacent battery cells. However, these measures are relatively single in terms of heat insulation effect, and can only play a physical blocking role, but cannot effectively suppress or alleviate the heat generated during the thermal runaway process, i.e., lack of direct regulation ability for the source of heat generation. SUMMARY

[0003] Therefore, the utility model provides a buffer heat insulation subassembly and battery pack, which can meet the requirements of battery pack heat insulation and heat dissipation performance, and can buffer and adjust the heat generated by the battery cell under actual battery pack fast charging / thermal runaway.

[0004] To solve the above technical problems, the utility model provides a buffer heat insulation subassembly arranged between the large faces of two batteries arranged in a first direction in a battery pack, comprising:

[0005] a heat insulation layer;

[0006] two heat conduction layers, each arranged on the opposite side of the heat insulation layer along the first direction, for heat conduction connection with the cooling plate in the battery pack, and the first direction is the thickness direction of the buffer heat insulation subassembly;

[0007] two phase change heat absorption layers, each arranged on the side of the heat conduction layer away from the heat insulation layer, for contact heat exchange with the large face of the battery, wherein the outer surface of the phase change heat absorption layer is wrapped with an encapsulation film, and the phase change heat absorption layer is encapsulated through the encapsulation film;

[0008] When the temperature in the battery pack exceeds the melting temperature of the phase change heat absorption layer, the phase change heat absorption layer melts to reduce the temperature in the battery pack;

[0009] When the temperature in the battery pack exceeds the vaporization temperature of the phase change heat absorption layer, the phase change heat absorption layer vaporizes to reduce the temperature in the battery pack;

[0010] The encapsulation film burns to generate inert gas to suppress thermal runaway of the battery pack when the temperature within the battery pack exceeds the combustion temperature of the encapsulation film;

[0011] The combustion temperature of the encapsulation film is higher than the vaporization temperature of the phase change heat absorption layer.

[0012] Further, the melting temperature of the phase change heat absorption layer is 45-55℃, and the vaporization temperature of the phase change heat absorption layer is 80-100℃.

[0013] The encapsulation film is an aluminum plastic film, and the combustion temperature of the aluminum plastic film ranges from 250-270℃.

[0014] Further, the heat conduction layer is made of metal material.

[0015] Further, the heat conduction layer has an L-shaped structure, including a plate portion and an extension portion, the plate portion extends along a second direction, the extension portion is arranged on one side of the plate portion along a first direction towards the phase change heat absorption layer, and the second direction is the height direction of the buffer and heat insulation assembly.

[0016] The two heat conduction layers are arranged in opposite directions along the first direction.

[0017] The phase change heat absorption layer has a plate-shaped structure, one side of the phase change heat absorption layer along the first direction is connected to the plate portion, and one side of the phase change heat absorption layer along the second direction is connected to the extension portion.

[0018] Further, the extension portion includes a first connecting segment connected to the phase change heat absorption layer, a second connecting segment arranged opposite to the first connecting segment along the second direction, and a third connecting segment connecting the first connecting segment and the second connecting segment.

[0019] The second connecting segment is used to connect to the cooling plate within the battery pack, and the third connecting segment is used to connect to the battery.

[0020] Further, the third connecting segment has an arc-shaped surface for connecting to the bottom corner of the shell of the battery.

[0021] Further, along the first direction, the length of the first connecting segment protruding from the plate portion is equal to the thickness of the phase change heat absorption layer.

[0022] Further, a groove is formed between the side wall of the two heat conduction layers and the side of the heat insulation layer close to the extension portion along the second direction, and the groove is used to accommodate the overflow of the heat conduction glue.

[0023] This utility model also provides a battery pack, including a cooling plate, a cell module, and the aforementioned buffer and heat insulation component. The cell module includes a plurality of cells arranged in an array on the cooling plate with a first direction and a third direction as the row and column directions, respectively. The buffer and heat insulation component is disposed between any two adjacent cells along the first direction.

[0024] Furthermore, it also includes a thermally conductive adhesive layer located between the battery cell module and the cooling plate, and both the battery and the thermally conductive layer are connected to the cooling plate through the thermally conductive adhesive layer.

[0025] Compared with the prior art, the above-mentioned technical solution of this utility model has the following advantages: The buffer heat insulation component and battery pack of this utility model include a heat insulation layer, a heat conducting layer, a phase change heat absorption layer, and an encapsulation film. The heat insulation layer can prevent heat conduction between adjacent batteries, the heat conducting layer can conduct the heat of the battery to the cooling structure of the battery pack, and the phase change heat absorption layer can absorb heat according to the temperature inside the battery pack and return to its original form after the temperature inside the battery pack drops, thus realizing thermal management inside the battery pack. When the temperature inside the battery pack reaches the phase change temperature, the phase state of the phase change heat absorption layer changes to a gaseous state. When the temperature inside the battery pack exceeds the melting temperature of the encapsulation film, the encapsulation film melts and burns to generate inert gas, venting oxygen inside the battery pack and suppressing thermal runaway. This utility model can meet the requirements of battery pack heat insulation and heat dissipation performance, and can buffer and adjust the heat generated by the cells under actual battery pack fast charging / thermal runaway. Attached Figure Description

[0026] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0027] Figure 1 This is a perspective view of the buffer and heat insulation component disclosed in Embodiment 1 of this utility model;

[0028] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0029] Figure 3 This is a partial schematic diagram of the heat-conducting layer disclosed in Embodiment 1 of this utility model;

[0030] Figure 4 This is a perspective view of the battery module disclosed in Embodiment 1 of this utility model;

[0031] Figure 5 for Figure 4 A magnified view of a section at point B in the middle;

[0032] Figure 6 This is a partial schematic diagram of the heat-conducting layer disclosed in Embodiment 2 of this utility model.

[0033] The description of the figures: 1, buffer thermal insulation assembly; 11, thermal insulation layer; 12, heat conduction layer; 121, plate part; 122, extension part; 1221, first connecting section; 1222, second connecting section; 1223, third connecting section; 13, phase change heat absorption layer; 18, groove; 2, cooling plate; 3, battery; 4, heat conduction glue layer; 5, nylon end plate. DETAILED DESCRIPTION

[0034] The utility model will be further described below in combination with the drawings and specific embodiments, so that the person skilled in the art can better understand the utility model and can be implemented, but the embodiment is not as the limitation of the utility model. Example one

[0035] Referring to Figures 1 to 3 The utility model discloses a buffer thermal insulation assembly one embodiment.

[0036] The buffer thermal insulation assembly is arranged between the large surface of two batteries arranged along the first direction in the battery pack, and the buffer thermal insulation assembly 1 comprises:

[0037] A thermal insulation layer 11;

[0038] Two heat conduction layers 12 are arranged on the opposite sides of the thermal insulation layer 11 along the first direction, and are used for heat conduction connection with the cooling plate in the battery pack, and the first direction is the thickness direction of the buffer thermal insulation assembly 1;

[0039] Two phase change heat absorption layers 13 are arranged on the side of the heat conduction layer 12 away from the thermal insulation layer 11, and are used for contact heat exchange with the large surface of the battery, wherein the outer surface of the phase change heat absorption layer 13 is wrapped with an encapsulation film, and the phase change heat absorption layer is encapsulated through the encapsulation film;

[0040] When the temperature in the battery pack exceeds the melting temperature of the phase change heat absorption layer 13, the phase change heat absorption layer melts to reduce the temperature in the battery pack;

[0041] When the temperature in the battery pack exceeds the vaporization temperature of the phase change heat absorption layer 13, the phase change heat absorption layer vaporizes to reduce the temperature in the battery pack;

[0042] When the temperature in the battery pack exceeds the combustion temperature of the encapsulation film, the encapsulation film burns to produce inert gas to inhibit the thermal runaway of the battery pack;

[0043] The combustion temperature of the encapsulation film is higher than the vaporization temperature of the phase change heat absorption layer.

[0044] The heat insulation layer 11 is a layer of heat insulation material with low thermal conductivity, preventing heat transfer between the two heat conduction layers 12 on both sides, avoiding mutual influence between the two batteries on both sides of the same buffer heat insulation assembly 1.

[0045] The heat conduction layer 12 is a layer of heat conduction material with high thermal conductivity, which can quickly conduct the heat generated by the battery to the cooling structure of the battery pack, achieving heat dissipation.

[0046] The phase change heat absorption layer 13, i.e. the phase change material, has the characteristic of phase change when the temperature reaches a specified range. When the phase change heat absorption layer 13 changes phase, it will absorb or release heat, thereby changing the temperature inside the battery pack. Because the phase change material changes phase during the phase change process, in order to prevent the phase change material from leaking and to keep the phase change material in the desired position and desired form, the phase change material needs to be encapsulated. In this embodiment, the phase change heat absorption layer is solid at room temperature. When the temperature inside the battery pack exceeds the melting temperature of the phase change heat absorption layer, the phase change heat absorption layer absorbs heat and melts, tending to be a high-viscosity paste-like substance similar to silicone rubber. When the temperature inside the battery pack exceeds the vaporization temperature of the phase change heat absorption layer, the phase change heat absorption layer absorbs heat and vaporizes. When the temperature inside the battery pack reaches the combustion temperature of the encapsulation film, the encapsulation film burns and melts, producing inert gas, which consumes the oxygen inside the battery pack, thereby suppressing thermal runaway inside the battery pack.

[0047] The heat regulation mechanism of the buffer heat insulation assembly 1 under the conditions of fast charging and thermal runaway of the battery pack is as follows:

[0048] 1) Battery pack fast charging process: In the early stage of fast charging, a large amount of heat energy is rapidly accumulated inside the battery. Due to the limited heat conduction capacity of the existing cooling structure of the battery pack, part of the heat cannot be discharged in time. At this time, the phase change heat absorption layer 13 in the buffer heat insulation assembly 1 begins to play a role, absorbing part of the heat energy and weakening the battery side reaction; at the same time, the heat conduction layer 12 transfers the remaining heat to the existing cooling structure of the battery pack through heat conduction, such as transferring the remaining heat to the flowing cooling liquid, thereby gradually reducing the battery temperature. With the drop in battery temperature, the phase change heat absorption layer 13 releases the absorbed heat energy and restores its original form, completing a heat management cycle.

[0049] 2) When the battery package is in thermal runaway, the heat in the battery package rises rapidly. At this time, the phase change heat absorption layer 13 rapidly absorbs heat, and when the phase change material reaches the melting temperature, the phase change heat absorption layer 13 changes from solid to paste, which plays a role of heat buffer, effectively delaying the spread speed of thermal runaway. When the temperature further reaches the vaporization temperature of the phase change material, the internal pressure of the packaging film increases, the thermal conductivity decreases, and the heat insulation effect between the battery cells is further strengthened. Finally, when the temperature in the battery package reaches the combustion temperature of the packaging film, the packaging film burns to produce inert gas, consume oxygen in the battery package, and suppress thermal runaway.

[0050] In the embodiment, the melting temperature of the phase change heat absorption layer 13 is 45-55℃, and the vaporization temperature of the phase change heat absorption layer 13 is 80-100℃.

[0051] The melting temperature of the phase change heat absorption layer 13 is set to 45-55℃, that is, when the temperature in the battery package is 45-55℃, the phase change heat absorption layer begins to melt from solid to paste and absorbs the heat in the battery package. The vaporization temperature of the phase change heat absorption layer 13 is set to 80-100℃, that is, when the temperature in the battery package is 80-100℃, the phase change heat absorption layer begins to vaporize into gas and absorbs the heat in the battery package. Specifically, the melting temperature can be set to 45℃, 50℃, 55℃, or any temperature between two values; the vaporization temperature can be set to 80℃, 85℃, 90℃, 95℃, 100℃, or any temperature between two values.

[0052] In the embodiment, the packaging film is an aluminum plastic film, and the melting temperature of the aluminum plastic film is 250-270℃.

[0053] The aluminum plastic film is a multi-layer material composed of an aluminum foil and a plastic film, mainly used for packaging lithium ion batteries. The structure of the aluminum plastic film usually includes an outer plastic layer, a middle aluminum foil layer, and an inner plastic layer. The outer plastic layer usually has good weather resistance, wear resistance, and printing adaptability, the middle aluminum foil layer endows the aluminum plastic film with excellent barrier properties, which can effectively block the invasion of oxygen, water vapor, and light, and the inner plastic layer needs to have good chemical stability and heat sealing performance. The aluminum plastic film can meet the packaging requirements of the phase change heat absorption layer in the utility model, and produces carbon dioxide, nitrogen, and other inert gases when it burns, which can meet the requirements of inhibiting thermal runaway in the battery package. The combustion temperature of the aluminum plastic film is set to 250-270℃, that is, when the temperature in the battery package reaches 250-270℃, the aluminum plastic film burns to produce inert gas and suppresses the thermal runaway in the battery package. Specifically, the combustion temperature of the aluminum plastic film can be set to 250℃, 255℃, 260℃, 265℃, 270℃, or any temperature between two values.

[0054] In the embodiment, the heat conduction layer 12 is made of metal material.

[0055] The thermal conductivity of metal is generally good. Metal materials have good thermal conductivity, are good conductors of heat, and have fast heat conduction and heat dissipation. The heat conduction layer 12 can be made of metal materials such as copper sheets. In this embodiment, the heat conduction layer 12 is preferably made of aluminum sheets with a thickness of 0.2-0.5 mm. Aluminum sheets have the advantages of small density, good corrosion resistance and weather resistance, good plasticity and processing performance, good thermal conductivity, good mechanical properties, and good surface treatment properties. At the same time, the comprehensive cost of aluminum sheets is relatively low, which ensures that the cost of the buffer and thermal insulation assembly 1 will not be too high. Through the heat conduction layer 12, the battery surface and the liquid cooling plate at the bottom of the battery pack can be thermally connected, improving the thermal conductivity efficiency.

[0056] In this embodiment, the heat conduction layer 12 has an L-shaped structure, including a plate portion 121 and an extension portion 122. The plate portion 121 extends in the second direction, and the extension portion 122 is arranged on the side of the plate portion 121 facing the phase change heat absorption layer 13 in the first direction. The second direction is the height direction of the buffer and thermal insulation assembly 1.

[0057] The two heat conduction layers 12 are arranged in opposite directions along the first direction.

[0058] The phase change heat absorption layer 13 has a plate-shaped structure. One side of the phase change heat absorption layer 13 along the first direction is connected to the plate portion 121, and the other side of the phase change heat absorption layer 13 along the second direction is connected to the extension portion 122.

[0059] First, the gap between adjacent two batteries is limited, so the size of the buffer and thermal insulation assembly 1 along the first direction should match the gap size between the adjacent two batteries. In this embodiment, the thickness direction of the plate portion 121 and the phase change heat absorption layer 13 are both in the first direction, ensuring that the thickness of the buffer and thermal insulation assembly 1 along the first direction is small, which is convenient for being arranged in the gap between the adjacent two batteries.

[0060] Secondly, when heat exchange is carried out, the larger the contact area, the higher the heat exchange efficiency. In this embodiment, the plate portion 121 and the extension portion 122 of the heat conduction layer 12 are in contact with the phase change heat absorption layer 13. The contact area between the heat conduction layer 12 and the structure below the buffer and thermal insulation assembly 1 is large, and the heat exchange efficiency is high, which is convenient for the heat conduction layer 12 to quickly conduct the heat of the battery away.

[0061] In this embodiment, the extension portion 122 includes a first connecting segment 1221 connected to the phase change heat absorption layer 13, a second connecting segment 1222 arranged opposite to the first connecting segment 1221 along the second direction, and a third connecting segment 1223 connecting the first connecting segment 1221 and the second connecting segment 1222.

[0062] The second connecting section 1222 is used for adhering connection with the cooling plate in the battery pack; and the third connecting section 1223 is used for adhering connection with the battery.

[0063] The extension 122 is in contact connection with the phase change heat absorption layer 13, the battery and the cooling plate. On one hand, the structures in contact with each other can be positioned with each other, improving the structural stability. On the other hand, the structures in contact with each other can transfer heat with each other, improving the heat dissipation efficiency.

[0064] In the embodiment, the third connecting section 1223 is an arc surface, which is used for adhering connection with the bottom corner of the shell of the battery.

[0065] Specifically, the first connecting section 1221 and the second connecting section 1222 are both linear horizontal surfaces; and the third connecting section 1223 is an arc surface.

[0066] The first connecting section 1221 is a horizontal surface, which can better support the lower side of the phase change heat absorption layer 13. The second connecting section 1222 is a horizontal surface, which can better support other structures below the buffer and heat insulation assembly 1. The third connecting section 1223 is towards the battery cell. The third connecting section 1223 is an arc surface, which has two advantages: ① The bottom corner between the bottom surface and the side surface of the shell of the battery is generally a circular corner. The third connecting section 1223 is an arc surface, which can be matched and adhered with the bottom corner of the battery. The contact area between the battery and the heat conduction layer 12 is larger, which increases the heat dissipation area of the battery and strengthens the heat dissipation of the battery. ② When the third connecting section 1223 is an arc surface, the area of the second connecting section 1222 can be maximized. The contact area between the heat conduction layer 12 and the structures below the buffer and heat insulation assembly 1 is maximized. The heat conduction layer 12 can be more stably supported on the structures below the buffer and heat insulation assembly 1, preventing the installation position of the buffer and heat insulation assembly 1 from being deviated due to the gravity during the installation process. ③ The connection strength between the battery and the bottom cooling plate and the buffer and heat insulation assembly can also be improved.

[0067] In the embodiment, along the first direction, the length of the first connecting section 1221 protruding from the plate portion 121 is equal to the thickness of the phase change heat absorption layer 13.

[0068] The phase change heat absorption layer 13 is unstable in shape during the phase change process. If the phase change heat absorption layer 13, the heat conduction layer 12 and the heat insulation layer 11 of the buffer heat insulation assembly 1 are in a common laminated structure, the shape of the phase change heat absorption layer 13 will change when the phase change heat absorption layer 13 changes, which will cause the size of the entire buffer heat insulation assembly 1 in the first direction to change. Therefore, the buffer heat insulation assembly 1 is prone to position deviation between the two battery cells. In the embodiment, the length of the first connecting section 122 protruding from the plate portion 121 is equal to the thickness of the phase change heat absorption layer 13, which can support the phase change heat absorption layer 13. Even if the shape of the phase change heat absorption layer 13 changes, the size of the heat conduction layer 12 in the first direction will not change, and the size of the entire buffer heat insulation assembly 1 in the first direction will not change. Therefore, the buffer heat insulation assembly 1 is not prone to position deviation.

[0069] In the embodiment, a groove 18 is formed between the side wall of the two heat conduction layers 12 and the side of the heat insulation layer 11 close to the extension portion 122 in the second direction, and the groove 18 is used to accommodate the overflow heat conduction adhesive.

[0070] In the process of production, the lower end of the battery and the buffer heat insulation assembly is connected to the bottom plate or the cooling plate of the battery pack through the heat conduction adhesive, and the battery will extrude the heat conduction adhesive layer. If the buffer heat insulation assembly 1 is in a common laminated structure, that is, the bottom edge of the buffer heat insulation assembly 1 is flush, on the one hand, the heat conduction adhesive may be extruded into the gap between the buffer heat insulation assembly 1 and the buffer heat insulation assembly, which will destroy the existing structure shape or contact relationship. On the other hand, the heat conduction adhesive is used to conduct the heat of the battery to the existing cooling structure of the battery pack. If there is no groove to accommodate the overflow adhesive, the heat conduction adhesive will be extruded to other positions, which will cause the thickness of the adhesive layer of the heat conduction adhesive to be uneven, the heat conduction speed to be inconsistent, and the heat dissipation of the battery cell to be affected. In the embodiment, the groove 18 is reserved, and the heat conduction adhesive will be extruded into the groove 18. The heat conduction adhesive will not destroy the existing structure shape and contact relationship, and the heat conduction adhesive will be in more sufficient contact with the heat conduction layer 12, which can enhance the heat conduction effect of the heat conduction adhesive.

[0071] In the embodiment, the phase change material is a heat-enhanced polymer heat conduction material, which has excellent compressibility, fills the gap between the heat source and the heat sink, removes the air in the gap, improves the heat conduction efficiency, and greatly reduces the thermal resistance. The characteristics and advantages of the phase change material are as follows: ① high thermal conductivity and low thermal resistance; ② solid at room temperature and liquid after the phase change temperature point; ③ self-adhesive, easy to operate; ④ good effect in some applications with extremely high heat dissipation requirements. At present, it is mainly applied to high-power LED, high-end computer and other applications with high heat dissipation requirements, communication equipment, wireless base station, power converter, storage module and chip. The characteristic parameters of the phase change material are shown in the following table.

[0072] Custom thickness (mm) 0.2-0.5 Thickness tolerance (%) ±10 Working temperature (°C) -20-120 Melting temperature (°C) 45-55 Vaporization temperature (°C) 80-100 Gas density (kg / m 3 ) 0.8-0.9 Volume resistance (Ω-cm) 1.0·1013-2.0·1010 Thermal conductivity (W / (m-K)) 3.0-8.0 Dielectric constant (1 MHz) 0.05-3.1

[0073] The heat insulation layer 11 needs to have good heat insulation effect, and can be aerogel or foam, etc. In the embodiment, the heat insulation layer 11 is preferably silica foam, and the thickness of the silica foam is 0.2-0.5 mm. The silica foam plays a crucial role in suppressing the lateral conduction of excessive heat, thereby maintaining the stability of the overall working performance of the battery pack. The silica foam exhibits excellent properties of silicone rubber at room temperature, including excellent rebound performance, excellent weather resistance, and long-term working stability. Even in a high-temperature extreme environment, the silica foam can still maintain its good rubber state properties. In addition, the pore structure inside the silica foam is rich in air, and since air is the best heat insulation medium in nature, this property greatly enhances the heat insulation performance of the silica foam.

[0074] Referring to Figure 4 and Figure 5 An embodiment of the battery module is disclosed.

[0075] The battery pack includes a cooling plate 2, a battery cell module, and the above-mentioned buffer heat insulation assembly. The battery cell module includes a plurality of batteries 3 arranged in a first direction and a third direction as the row direction and the column direction on the cooling plate, respectively. The buffer heat insulation assembly 1 is arranged between any two adjacent batteries 3 along the first direction.

[0076] The cooling plate 2 is provided with a water inlet joint and a water outlet joint. The cooling plate 2 is a flow channel plate. The cooling liquid enters the flow channel of the cooling plate 2 from the water inlet, flows through the designed flow channel, and is finally discharged from the water outlet of the cooling plate 2. In the embodiment, the water inlet is located at the middle position of the cooling plate, and the two water outlets are respectively arranged on the two sides of the water inlet. The cooling liquid is introduced into the inside of the cooling plate 2 from the central water inlet, and then its flow is evenly distributed into two streams, which flow through the designed flow channel and are finally discharged from the water outlets on both sides of the cooling plate 2. The split flows are combined in the water outlet manifold. This flow channel layout strategy cleverly realizes the simultaneous heat dissipation of the left and right battery cell module assemblies, which not only significantly improves the uniformity of the temperature distribution of the battery cell module, but also effectively enhances the heat dissipation performance of the cooling plate as a whole. The cooling plate is a flow channel plate formed by stamping the upper plate and the composite material, and is precisely combined by roll bonding process.

[0077] In the embodiment, a heat-conducting adhesive layer 4 is arranged between the battery cell module and the cooling plate 2. The battery 3 and the heat-conducting layer 12 are connected to the cooling plate 2 through the heat-conducting adhesive layer 4.

[0078] The heat-conducting adhesive is an adhesive with excellent heat-conducting performance, mainly used for heat dissipation and bonding of electronic components. In the embodiment, the battery cell module and the cooling plate need to be fixed together and conduct heat, so connecting the battery cell module and the cooling plate 2 by the heat-conducting adhesive can meet the requirements. Embodiment two

[0079] Another embodiment of the buffering and heat insulation assembly is disclosed in the utility model.

[0080] Referring to Figure 6 The third connecting section 1223 is a vertical surface in a straight line type, so as to facilitate the production of the heat conduction layer 12, and at this time, a gap exists between the extension 122 and the battery shell, which can be filled by heat conduction structure glue, so as to ensure the connection firmness between the battery and the buffering and heat insulation assembly and the cooling plate.

[0081] Obviously, the above embodiments are only examples for clearly illustrating, and are not limitation to the embodiments. For ordinary skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, all the embodiments need not and cannot be exhausted. The obvious changes or variations derived therefrom are still within the protection scope of the utility model.

Claims

1. A cushioning and thermal insulation assembly provided between large faces of two batteries arranged in a first direction in a battery pack, characterized by, The buffer and thermal insulation assembly (1) comprises: a thermal insulation layer (11); a heat conduction layer (12), two of which are respectively arranged on opposite sides of the thermal insulation layer (11) along a first direction, for heat conduction connection with the cooling plate in the battery pack, the first direction being the thickness direction of the buffer and thermal insulation assembly (1); a phase change heat absorption layer (13), two of which are respectively arranged on the side of the heat conduction layer (12) away from the thermal insulation layer (11), for contact heat exchange with the large surface of the battery, wherein the outer surface of the phase change heat absorption layer (13) is wrapped with an encapsulating film, and the phase change heat absorption layer is encapsulated through the encapsulating film.

2. The cushioning insulation assembly of claim 1, wherein, The melting temperature of the phase change heat absorption layer is 45-55℃, and the vaporization temperature of the phase change heat absorption layer is 80-100℃; The encapsulating film is an aluminum plastic film, and the combustion temperature range of the aluminum plastic film is 250-270℃.

3. The cushioning insulation assembly of claim 1, wherein, The heat conduction layer (12) is made of metal material.

4. The cushioning insulation assembly of claim 1, wherein, The heat conduction layer (12) has an L-shaped structure, comprising a plate part (121) and an extension part (122), the plate part (121) extends along a second direction, and the extension part (122) is arranged on the side of the plate part (121) along the first direction towards the phase change heat absorption layer (13), the second direction being the height direction of the buffer and thermal insulation assembly (1); The two heat conduction layers (12) are arranged in opposite directions along the first direction; The phase change heat absorption layer (13) has a plate-shaped structure, one side of the phase change heat absorption layer (13) along the first direction is connected with the plate part (121), and one side of the phase change heat absorption layer (13) along the second direction is connected with the extension part (122).

5. The cushioning insulation assembly of claim 4, wherein, The extension part (122) comprises a first connecting section (1221) connected with the phase change heat absorption layer (13), a second connecting section (1222) arranged opposite to the first connecting section (1221) along the second direction, and a third connecting section (1223) connecting the first connecting section (1221) and the second connecting section (1222); The second connecting section (1222) is used for abutting connection with the cooling plate in the battery pack, and the third connecting section (1223) is used for abutting connection with the battery.

6. The cushioning insulation assembly of claim 5, wherein, The third connecting section (1223) has an arc surface, for abutting connection with the bottom corner of the shell of the battery.

7. The cushioning insulation assembly of claim 5, wherein, Along the first direction, the length of the first connecting section (1221) protruding from the plate part (121) is equal to the thickness of the phase change heat absorption layer (13).

8. The cushioning insulation assembly of claim 4, wherein, The side of the thermal insulation layer (11) close to the extension part (122) along the second direction and the side walls of the two heat conduction layers (12) form a groove (18), and the groove (18) is used for accommodating the overflowed heat conduction adhesive.

9. A battery pack, characterized by, The battery module comprises a plurality of batteries (3) arranged in a first direction and a third direction as a row direction and a column direction on the cooling plate (2), and the buffer and thermal insulation assembly (1) is arranged between any two batteries (3) adjacent in the first direction.

10. The battery pack of claim 9, wherein, The battery module further comprises a heat-conducting adhesive layer (4) between the battery module and the cooling plate (2), and the battery (3) and the heat-conducting layer (12) are connected to the cooling plate (2) through the heat-conducting adhesive layer (4).

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