Thermal runaway barrier components, battery modules and battery packs

Abstract

The utility model relates to the technical field of battery safety, and in particular to a thermal runaway barrier component, including a base member and a hot melt member. The base member has a containing cavity, and a phase change medium is placed in the containing cavity. The vaporization temperature of the phase change medium is lower than the thermal runaway temperature of the battery cell. A vent hole is provided on the base member, and the vent hole is connected to the containing cavity. The hot melt member is attached to the base member, and the hot melt member blocks the vent hole. The melting point of the hot melt member is lower than the vaporization temperature of the phase change medium. When the battery cell has thermal runaway, the hot melt member will melt first, causing the vent hole to open, and the phase change medium will flow out of the vent hole, and quickly change phase in a high temperature environment to absorb heat, thereby reducing the temperature of the thermal runaway battery cell and preventing the spread of thermal runaway. The utility model also provides a battery module, including a plurality of battery cells and the above-mentioned thermal runaway barrier component, and the thermal runaway barrier component is sandwiched between adjacent battery cells. The utility model also provides a battery pack, including the above-mentioned battery module.

Description

Technical Field

[0001] The utility model relates to the technical field of battery safety, and in particular to a thermal runaway barrier component, a battery module and a battery pack. Background Art

[0002] As the core component of electric vehicles, the thermal safety performance of power batteries involves personal safety, so there are many thermal safety control schemes. The most widely used one is to add aerogel between adjacent battery cells to isolate and protect adjacent battery cells. However, for large-capacity ternary battery cells, because the energy carried by a single battery cell is large, aerogel can only delay the spread of thermal runaway between battery cells. As the thermal runaway time of the battery cell increases, the temperature of the hot and cold surfaces of the aerogel will tend to be consistent, and adjacent battery cells will also absorb heat to trigger thermal runaway. Therefore, the scheme of setting up aerogel can only delay the spread of thermal runaway between battery cells, and cannot reduce the temperature of the thermal runaway battery cell, and further block the spread of thermal runaway.

[0003] Therefore, there is an urgent need for a thermal runaway barrier component, a battery module and a battery pack to solve the above problems. Utility Model Content

[0004] The purpose of the utility model is to provide a thermal runaway barrier component, a battery module and a battery pack, which can reduce the temperature of a thermal runaway battery cell and help block the spread of thermal runaway.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A thermal runaway barrier component is provided, which is arranged between adjacent battery cells, and the thermal runaway barrier component comprises:

[0007] A base member, wherein the base member has a containing cavity, wherein a phase change medium is contained in the containing cavity, wherein a vaporization temperature of the phase change medium is lower than a thermal runaway temperature of the battery cell, and wherein an air leakage hole is provided on the base member, wherein the air leakage hole is connected to the containing cavity;

[0008] A hot melt component is attached to the base component, the hot melt component blocks the air leakage hole, and the melting point of the hot melt component is lower than the vaporization temperature of the phase change medium.

[0009] Optionally, a first adhesive layer is provided between the hot melt component and the base component, and the melting point temperature of the first adhesive layer is lower than the vaporization temperature of the phase change medium.

[0010] Optionally, the air leakage holes are provided on the first side and the second side of the base component, the first side and the second side face two adjacent battery cells respectively, and two hot melt components are provided, which are respectively attached to the first side and the second side.

[0011] Optionally, the thermal runaway barrier assembly further comprises an insulating member, which is attached to a side of the hot melt member facing away from the base member to isolate the hot melt member from the battery cell, and a melting point temperature of the insulating member is higher than a thermal runaway temperature of the battery cell.

[0012] Optionally, a plurality of ventilation holes are formed through the insulating member, and one end of the plurality of ventilation holes faces the hot melt member, and the other end faces the battery core.

[0013] Optionally, a second adhesive layer is provided between the insulating member and the hot-melt member, and the melting point temperature of the second adhesive layer is lower than the vaporization temperature of the phase change medium.

[0014] Optionally, the base member is a plate-like structure, and / or the hot melt member is a sheet-like structure.

[0015] Optionally, the phase change medium is a flame retardant medium.

[0016] Provided is a battery module, comprising a plurality of battery cells and the above-mentioned thermal runaway barrier assembly, wherein the thermal runaway barrier assembly is sandwiched between adjacent battery cells.

[0017] A battery pack is provided, comprising the above-mentioned battery module.

[0018] Beneficial effects of the utility model:

[0019] The utility model provides a thermal runaway barrier component, including a base part and a hot melt part. The base part has a containing cavity, and the containing cavity contains a phase change medium, the vaporization temperature of the phase change medium is lower than the thermal runaway temperature of the battery cell, and the base part is provided with an air leak hole, which is connected to the containing cavity. The hot melt part is attached to the base part, and the hot melt part blocks the air leak hole, and the melting point of the hot melt part is lower than the vaporization temperature of the phase change medium. When a battery cell has thermal runaway and the temperature rises to the thermal runaway temperature, the hot melt part will melt first, causing the air leak hole to open, and the phase change medium will flow out of the air leak hole, and quickly phase change and absorb heat in a high temperature environment, thereby reducing the temperature of the thermal runaway battery cell and preventing the spread of thermal runaway.

[0020] The utility model also provides a battery module, comprising a plurality of battery cells and the above-mentioned thermal runaway barrier component, wherein the thermal runaway barrier component is sandwiched between adjacent battery cells, and the thermal runaway barrier component can reduce the temperature of the thermal runaway battery cells and prevent the spread of thermal runaway.

[0021] The utility model also provides a battery pack, comprising the above-mentioned battery module, the battery pack can reduce the temperature of the thermal runaway battery cell and prevent the spread of thermal runaway. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1This is a schematic structural diagram of a basic component provided in the first embodiment of the present utility model from a first viewing angle;

[0023] Figure 2 It is a structural schematic diagram of the second viewing angle of the basic component provided by the first embodiment of the utility model;

[0024] Figure 3 yes Figure 2 Middle AA section view;

[0025] Figure 4 yes Figure 3 The enlarged view of point B in the middle;

[0026] Figure 5 It is an exploded view of the base member and the hot melt member provided in the first embodiment of the utility model;

[0027] Figure 6 It is an exploded view of the thermal runaway barrier assembly provided in the first embodiment of the utility model;

[0028] Figure 7 It is a partial structural schematic diagram of a battery module provided in the second embodiment of the present utility model;

[0029] Figure 8 It is a partial structural exploded diagram of the battery module provided in the second embodiment of the present utility model.

[0030] In the figure:

[0031] 1. Basic component; 11. Accommodating cavity; 12. Air vent;

[0032] 2. Hot melt parts; 3. Insulation parts;

[0033] 100. Thermal runaway barrier component; 200. Battery cell. DETAILED DESCRIPTION

[0034] The technical solution of the utility model is further described below in conjunction with the accompanying drawings and implementation methods. It is understood that the specific embodiments described herein are only used to explain the utility model, rather than to limit the utility model. It should also be noted that, for the convenience of description, only the parts related to the utility model are shown in the accompanying drawings, rather than all.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0037] Embodiment 1

[0038] like Figure 1-Figure 6 As shown, the thermal runaway barrier assembly 100 of this embodiment includes a base member 1 and a hot melt member 2. The base member 1 has a receiving cavity 11, and the receiving cavity 11 contains a phase change medium, and the vaporization temperature of the phase change medium is lower than the thermal runaway temperature of the battery cell 200. The base member 1 is provided with a vent hole 12, and the vent hole 12 is connected to the receiving cavity 11. The hot melt member 2 is attached to the base member 1, and the hot melt member 2 blocks the vent hole 12. The melting point of the hot melt member 2 is lower than the vaporization temperature of the phase change medium.

[0039] When a battery cell 200 experiences thermal runaway and the temperature rises to the thermal runaway temperature, the hot melt component 2 will melt first, causing the vent hole 12 to open, and the phase change medium will flow out of the vent hole 12 and quickly undergo phase change to absorb heat in a high temperature environment, thereby reducing the temperature of the battery cell 200 in thermal runaway and preventing the spread of thermal runaway.

[0040] The melting point of the hot melt component 2 is lower than the vaporization temperature of the phase change medium, which can prevent the phase change medium from vaporizing and rapidly expanding in the accommodating cavity 11 before the hot melt component 2 melts and the air leakage hole 12 opens, causing excessive internal pressure.

[0041] In order to further improve the flame retardant properties of the phase change medium, optionally, the phase change medium is a flame retardant medium, that is, the medium has the characteristics of phase change and heat absorption at the thermal runaway temperature of the battery cell 200 and flame retardant. Optionally, in this embodiment, the phase change medium is liquid nitrogen, liquid carbon dioxide or other phase change flame retardant liquid or solid, as long as it can absorb heat and gasify, and there is no limitation here.

[0042] In order to adapt to the rectangular battery cell 200, optionally, in this embodiment, the base member 1 is a plate-like structure. Optionally, in this embodiment, the base member 1 is a metal plate with a hollow interior, and optionally, the metal plate is made of aluminum, which can ensure a certain structural strength while ensuring lightness. Of course, in other embodiments, the base member 1 can also be configured to have a curved sidewall to adapt to a cylindrical battery cell.

[0043] Optionally, the hot melt component 2 is a sheet structure, so as to be attached to the side wall of the base component 1. Optionally, in this embodiment, the hot melt component 2 is tin foil, and the melting point is about 230°C.

[0044] Optionally, a first glue layer is provided between the hot melt component 2 and the base component 1, and the melting point temperature of the first glue layer is lower than the vaporization temperature of the phase change medium. That is, when the battery cell 200 undergoes thermal runaway and the temperature rises to the thermal runaway temperature, the hot melt component 2 and the first glue layer will both melt, causing the vent hole 12 to open and the phase change medium to flow out of the vent hole 12. The first glue layer is a low melting point type and can be melted before the tin foil melts to prevent the phase change medium from being affected. Optionally, the first glue layer is a solid glue or a liquid glue, the solid glue can be a double-sided glue, and the liquid glue can be a polyurethane potting glue to ensure the sealing performance.

[0045] Optionally, the first side and the second side of the base member 1 are both provided with vent holes 12, the first side and the second side are respectively facing two adjacent battery cells 200, two hot melt components 2 are provided, and the two hot melt components 2 are respectively attached to the first side and the second side, that is, a thermal runaway barrier assembly 100 can achieve thermal runaway cooling barrier for two adjacent battery cells 200. Of course, in other embodiments, the base member 1 can also be provided with three, four or more side surfaces with vent holes 12 according to the shape and arrangement characteristics of the battery cells 200, and hot melt components 2 are attached to each surface with vent holes 12 to block the vent holes 12 within the normal temperature range.

[0046] Optionally, a plurality of air leakage holes 12 are evenly formed on each side surface of the base member 1 , and the hot melt member 2 covers all positions on the base member 1 having the air leakage holes 12 .

[0047] In the actual manufacturing process, it is necessary to first stick tin foil on one side of the base member 1 to block the air leakage hole 12 on this side. After confirming that the tin foil is fixed, liquid nitrogen is poured from the air leakage hole 12 on the other side of the base member 1, and then tin foil is also stuck on this side to block it, and the packaging is completed.

[0048] Optionally, in order to prevent the aluminum material or tin foil from contacting and conducting with the battery cell 200, and to insulate and block the adjacent battery cells 200, the thermal runaway blocking assembly 100 further includes an insulating member 3, which is attached to the side of the hot melt member 2 that is away from the base member 1, so as to block the hot melt member 2 and the battery cell 200, thereby playing the role of insulation protection. The melting point of the insulating member 3 is higher than the thermal runaway temperature of the battery cell 200, so as to ensure that the insulating member 3 always has an insulation function during the thermal runaway process.

[0049] Optionally, the insulating member 3 covers the entire area where the hot melt member 2 is located, and a plurality of vents are formed through the insulating member 3, one end of each of the vents faces the hot melt member 2, and the other end faces the battery cell 200. The vaporized phase change medium can reach the battery cell 200 through the vents. Optionally, the vents are evenly distributed on the insulating member 3, so that the vaporized phase change medium can be evenly diffused to the surface of the battery cell 200, thereby evenly cooling the battery cell 200.

[0050] Optionally, in this embodiment, the insulating member 3 is a foam, which can prevent the battery cell 200 from directly contacting the aluminum material or tin foil, and play a role in insulation protection. The foam is an open-cell foam, and after molding, the overall structure is a void structure, and the vaporized phase change medium can smoothly pass through the foam to reach the battery cell 200 to achieve cooling and flame retardancy. The foam can withstand a high temperature of 500°C and will not melt and fail in thermal runaway.

[0051] Optionally, a second adhesive layer is provided between the insulating member 3 and the hot melt member 2, and the melting point of the second adhesive layer is lower than the vaporization temperature of the phase change medium. That is, in the process of the thermal runaway triggering temperature continuously increasing, the heat reaches the second adhesive layer through the vent holes of the insulating member 3, and the second adhesive layer will melt first, so as to avoid the second adhesive layer blocking the outflow path of the phase change medium, and ensure that the battery cell 200 in thermal runaway can be cooled in time. Optionally, the second adhesive layer can be double-sided adhesive.

[0052] When the thermal runaway of the battery cell 200 is triggered, the battery cell 200 releases energy, and the temperature of the battery cell 200 quickly reaches above 300°C. Since the melting point of the tin foil of the packaging base member 1 is only about 230°C, and the melting points of the first and second adhesive layers are also less than 230°C, the heat released by the battery cell 200 is transferred from the open-cell foam to the second adhesive layer, the packaging tin foil, and the first adhesive layer, and the three will melt as the temperature rises. After the second adhesive layer, the packaging tin foil, and the first adhesive layer melt, the packaging fails, and the vent hole 12 begins to exhaust. Since the cooling and flame-retardant liquid nitrogen or liquid carbon dioxide and other media continuously absorb heat during the process of changing from liquid to gas, the low-temperature gas is transferred from the foam gap to the battery cell 200, and the low-temperature gas continues to absorb the heat of the thermal runaway battery cell 200 until the energy release of the thermal runaway battery cell 200 is completed. In this process, the flame-retardant properties of the phase change medium will also help slow down the burning speed of the battery cell 200. Under the effects of the two aspects, the temperature of the battery cell 200 adjacent to the thermal runaway battery cell 200 is ensured to be kept within the thermal runaway trigger temperature, thereby achieving a blocking effect between the thermal runaway battery cells 200. Optionally, the reserve of the phase change medium can be set according to the specifications of the battery cell 200 to further ensure thermal runaway blocking.

[0053] Embodiment 2

[0054] like Figure 7-Figure 8As shown, this embodiment provides a battery module, including multiple battery cells 200 and the thermal runaway barrier assembly 100 in the first embodiment. The thermal runaway barrier assembly 100 is sandwiched between adjacent battery cells 200. The thermal runaway barrier assembly 100 can reduce the temperature of the thermal runaway battery cells 200 and prevent the spread of thermal runaway.

[0055] Optionally, both sides of the thermal runaway barrier assembly 100 are in direct contact with adjacent battery cells 200 , which can save the internal space of the battery module and improve the heat conduction efficiency.

[0056] Optionally, the battery module has M rows of battery cells 200, each row of battery cells 200 is provided with N battery cells, M is a positive integer, and N is a positive integer greater than or equal to 2. Optionally, a thermal runaway barrier assembly 100 is provided between every two adjacent battery cells 200, that is, N-1 thermal runaway barrier assemblies 100 are provided in a row of battery cells 200, and the battery module is provided with at least M×(N-1) thermal runaway barrier assemblies 100.

[0057] Embodiment 3

[0058] This embodiment provides a battery pack, including the battery module in the second embodiment, and the battery pack can reduce the temperature of the thermal runaway battery cell 200 and prevent the spread of thermal runaway.

[0059] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A thermal runaway barrier assembly, characterized in that: Arranged between adjacent battery cells (200), the thermal runaway barrier assembly (100) comprises: A base member (1), wherein the base member (1) has a containing cavity (11), wherein a phase change medium is contained in the containing cavity (11), wherein the vaporization temperature of the phase change medium is lower than the thermal runaway temperature of the battery cell (200), and wherein an air leakage hole (12) is provided on the base member (1), wherein the air leakage hole (12) is connected to the containing cavity (11); A hot melt component (2), the hot melt component (2) is attached to the base component (1), the hot melt component (2) blocks the air leakage hole (12), and the melting point temperature of the hot melt component (2) is lower than the vaporization temperature of the phase change medium.

2. The thermal runaway barrier assembly according to claim 1, characterized in that: A first adhesive layer is provided between the hot melt component (2) and the base component (1), and the melting point temperature of the first adhesive layer is lower than the vaporization temperature of the phase change medium.

3. The thermal runaway barrier assembly according to claim 1, characterized in that: The first side and the second side of the base member (1) are both provided with the vent holes (12), the first side and the second side are respectively oriented toward two adjacent battery cells (200), two hot melt components (2) are provided, and the two hot melt components (2) are respectively attached to the first side and the second side.

4. The thermal runaway barrier assembly according to claim 1, characterized in that: The thermal runaway barrier assembly (100) further comprises an insulating member (3), wherein the insulating member (3) is attached to a side of the hot melt member (2) facing away from the base member (1) to isolate the hot melt member (2) from the battery cell (200), and the melting point of the insulating member (3) is higher than the thermal runaway temperature of the battery cell (200).

5. The thermal runaway barrier assembly according to claim 4, characterized in that: The insulating member (3) is provided with a plurality of ventilation holes, one end of each of the plurality of ventilation holes is directed toward the hot melt member (2), and the other end of each of the plurality of ventilation holes is directed toward the battery core (200).

6. The thermal runaway barrier assembly according to claim 4, characterized in that: A second adhesive layer is provided between the insulating component (3) and the hot melt component (2), and the melting point temperature of the second adhesive layer is lower than the vaporization temperature of the phase change medium.

7. The thermal runaway barrier assembly according to claim 1, characterized in that: The base component (1) is a plate-like structure, and / or the hot melt component (2) is a sheet-like structure.

8. The thermal runaway barrier assembly according to claim 1, characterized in that: The phase change medium is a flame retardant medium.

9. A battery module, characterized in that: It comprises a plurality of battery cells (200) and a thermal runaway barrier assembly according to any one of claims 1 to 8, wherein the thermal runaway barrier assembly (100) is sandwiched between adjacent battery cells (200).

10. A battery pack, characterized in that: Comprising the battery module as claimed in claim 9.

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