Battery pack and electric device

Abstract

The application relates to the technical field of batteries, and provides a battery pack and a power utilization device. According to the battery pack provided by the embodiment of the application, since the accommodation space is communicated with the containing cavity through the communication path, when the cooling medium flows into the accommodation space, heat exchange can be performed between the large surface and the adjacent single battery, the heat dissipation area of the single battery is increased, and for the adjacent single battery, a "one-way water" type partition is formed, so that the heat transferred from the thermal runaway single battery to the adjacent single battery is less, and the safety performance of the battery pack is further improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery pack and an electrical device. Background Technology

[0002] In related technologies, the main solution for thermal runaway in power batteries is water cooling, which involves placing a cold plate at the bottom of the cell to circulate coolant and remove heat. However, existing cold plates cannot solve the safety issues that arise after thermal runaway of the cell. Utility Model Content

[0003] In view of this, this application provides a battery pack and an electrical device, with the aim of solving the above-mentioned technical problems to a certain extent.

[0004] According to a first aspect of this application, a battery pack is provided, the battery pack comprising: The box body, wherein a receiving cavity is provided inside the box body. Multiple individual battery cells are disposed within the receiving cavity. A cover plate, which is connected to the housing and seals the receiving cavity; A cooling component is disposed on the side of the plurality of individual cells near the cover plate, a cooling medium flows through the cooling component, and the cooling component is configured to undergo a phase change at a predetermined temperature to release the cooling medium to the individual cells.

[0005] Based on the above technical solutions, optionally, the single cell includes a large surface, and there is an accommodating space between two adjacent large surfaces of the single cell, wherein the large surface is the surface with the largest surface area on the upper surface of the single cell; The battery pack includes a limiting member that abuts against the large surfaces of two adjacent individual batteries, and the limiting member and the adjacent large surfaces enclose and define the accommodating space.

[0006] The limiting member has a connecting path, which connects the accommodating space and the receiving cavity.

[0007] Based on the above technical solutions, optionally, the limiting member includes a plurality of first limiting strips, which are connected end to end and form an opening facing the cooling member, the opening forming the connecting path, and the first limiting strips are elastic.

[0008] Based on the above technical solutions, optionally, the limiting member includes at least two second limiting strips, the at least two second limiting strips are located at the opening position and are spaced apart, forming the connecting path between two adjacent second limiting strips, and forming the connecting path between adjacent first limiting strips and second limiting strips, the second limiting strips being elastic.

[0009] Optionally, based on any of the above technical solutions, the battery pack further includes a heat insulation plate disposed between two adjacent large surfaces, and a limiting member is disposed between the heat insulation plate and an adjacent large surface, the limiting member, the heat insulation plate, and the large surface enclosing an accommodating space.

[0010] Optionally, based on any of the above technical solutions, a limiting member is provided between the heat insulation board and another adjacent large surface, and the limiting member, the heat insulation board, and the other large surface enclose a receiving space.

[0011] Optionally, based on any of the above technical solutions, the battery pack may further include a plurality of busbars electrically connected to the plurality of individual cells, and the cooling component abuts against the side of the busbars near the cover plate.

[0012] Optionally, based on any of the above technical solutions, the single cell also includes an explosion-proof valve, which is disposed on the side of the single cell near the cover plate, and the cooling component has multiple through holes for avoiding the explosion-proof valve.

[0013] Optionally, based on any of the above technical solutions, the battery pack further includes a buffer member disposed between the cooling member and the cover plate.

[0014] According to a second aspect of this application, an electrical device is provided, the electrical device comprising a battery pack as described above.

[0015] According to the battery pack provided in this application, when a single cell in the battery pack experiences thermal runaway, if the runaway temperature is within a predetermined temperature range, the multiple single cells can be cooled by a cooling component through which a cooling medium flows, thereby controlling the temperature of these single cells within the predetermined temperature range. If the runaway temperature exceeds the predetermined temperature, a phase change occurs in the cooling component, causing the cooling medium within the cooling component to be released to the multiple single cells. This allows the cooling medium to flow onto the single cells, physically cooling them. Therefore, the battery pack has better cooling capabilities, which is beneficial for controlling the thermal runaway of individual cells.

[0016] According to the battery pack provided in the embodiments of this application, since the accommodating space is connected to the accommodating cavity through the connecting path, when the cooling medium flows into the accommodating space, it can exchange heat with the adjacent single cells between the large surfaces, increasing the heat dissipation area of ​​the single cells. At the same time, it forms a "water"-like barrier for the adjacent single cells, so that the single cell in thermal runaway can transfer less heat to the adjacent single cells, further improving the safety performance of the battery pack.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of a two-dimensional view of a battery pack with the top cover omitted, according to an embodiment of this application, is shown. Figure 2 A schematic diagram showing a three-dimensional view of a portion of the structure of a battery pack according to an embodiment of this application is provided; Figure 3 This is a schematic diagram showing a two-dimensional view of another portion of the structure of the battery pack provided according to an embodiment of this application; Figure 4 A schematic diagram showing a three-dimensional view of another part of the structure of the battery pack provided according to an embodiment of this application; Figure 5 It shows Figure 4 A magnified view of point A in the diagram; Figure 6 A schematic diagram showing the relative positional relationship between the cooling component and the buffer component is shown.

[0020] Figure label: 10-Single cell; 11-Large surface; 12-Side surface; 13-Explosion-proof valve; 20-Accommodation space; 30-Connection path; 40-Cooling component; 50-Limiting component; 51-First limiting strip; 52-Second limiting strip; 53-Opening; 61-Heat insulation plate; 62-Side partition; 70-Buffered component; 80-Buffer component; 90-Box body; 91-Accommodation cavity; X-First direction; Z-Second direction; Y-Third direction. Detailed Implementation

[0021] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0025] According to a first aspect of the embodiments of this application, a battery pack is provided, which will be described below in conjunction with... Figures 1 to 6 Describe the structure of the battery pack in detail.

[0026] According to the battery pack provided in the embodiments of this application, the battery pack includes a plurality of individual cells 10, a cooling component 40, a cover plate, and a housing. In the embodiments, the aforementioned plurality of individual cells are disposed within a receiving cavity 91 of the housing, and the cover plate is connected to the housing 90 and seals the receiving cavity 91.

[0027] In one embodiment, a cooling member 40 is disposed on the side of the plurality of individual cells 10 near the cover plate. A cooling medium flows through the cooling member 40. The cooling member 40 is configured to undergo a phase change at a predetermined temperature to release the cooling medium to the aforementioned plurality of individual cells 10.

[0028] Thus, according to the battery pack provided in this application embodiment, when a single cell 10 in the battery pack experiences thermal runaway, if the temperature of the thermal runaway is within a predetermined temperature, the cooling member 40 through which the cooling medium flows can cool the multiple single cells 10 to control their temperature, thereby keeping the temperature of the single cells 10 within the predetermined temperature range. If the temperature of the thermal runaway is greater than the predetermined temperature, a phase change occurs in the cooling member 40, causing the cooling medium within the cooling member 40 to be released to the multiple single cells 10. This allows the cooling medium to flow onto the single cells 10, physically cooling them. Consequently, the battery pack has better cooling capabilities, which is beneficial for controlling the thermal runaway of the single cells 10.

[0029] Furthermore, according to the battery pack provided in the embodiments of this application, the thermal runaway of the individual battery 10 is controlled by using the cooling medium that is originally used to exchange heat with the individual battery 10 and flows within the cooling member 40, without adding any additional cooling structure. Therefore, compared with the solution that requires additional cooling structure, the battery pack provided in the embodiments of this application is beneficial to saving the internal space of the battery pack and improving the space utilization rate.

[0030] Furthermore, according to the battery pack provided in this application embodiment, even if the cooling medium within the cooling member 40 fails to circulate or circulates poorly due to a malfunction, the individual battery cells 10 can still be cooled by the cooling medium released from the cooling member 40. Additionally, in the embodiment, the cooling medium may be, for example, an insulating cooling medium.

[0031] In this embodiment, the cover plate and the housing 90 are fitted together in such a way that the cover plate is connected to the housing and covers the receiving cavity along the second direction Z intersecting the first direction X.

[0032] In the embodiments, the predetermined temperature mentioned above can be the phase transition point, such as the melting point, of the material forming the cooling member 40. As an example, the material of the cooling member 40 can be plastic, and its melting point, i.e., the predetermined temperature, can be, for example, 500°C.

[0033] In the battery pack provided according to the embodiments of this application, each of the aforementioned multiple individual battery cells 10 includes a large surface 11. Multiple battery cells are arranged along a first direction X, and in the first direction X, there is an accommodating space 20 between the large surfaces 11 of two adjacent individual battery cells 10. In the embodiments, the large surface 11 is the surface with the largest outer surface area on the individual battery cell.

[0034] In this embodiment, the battery pack includes a limiting member 50 disposed within the accommodating space 20, the limiting member 50 abutting against the large surface 11 of two adjacent individual battery cells 10. Essentially, the accommodating space 20 can be enclosed by the limiting member 50 and the adjacent large surface 11.

[0035] In this embodiment, the single cell 10 can be, for example, a square cell, the outer casing of which is generally rectangular in shape. The "large surface 11" mentioned above refers to the surface with the largest area of ​​the square cell.

[0036] In this embodiment, the aforementioned multiple individual battery cells 10 can be arranged in an array within the internal space of the housing 90.

[0037] In an embodiment, as an example, the first direction X and the second direction Z can be perpendicular to each other. For example, the first direction X can be the width direction of the square battery, that is, the plurality of individual cells 10 described above have a plurality of columns arranged along the width direction. These columns can be arranged along the length direction of the square battery, where the length direction can be the third direction Y mentioned later. The second direction Z mentioned above can be the height direction of the square battery. Within each column, the large surfaces 11 of adjacent individual cells 10 are opposite each other, that is, adjacent to each other, forming the above-described accommodating space 20 between such a pair of opposite large surfaces 11.

[0038] Furthermore, in the embodiment, adjacent single cells in the length direction are side 12 adjacent to each other, and a side partition 62 may be provided between the two side 12, which may be formed of heat-insulating material.

[0039] In the embodiment, the accommodating space 20 is formed by arranging adjacent single cells 10 at intervals in the width direction. The connecting path 30 mentioned here can be an opening of the accommodating space 20 for communicating with the external environment, or it can be a tubular structure set between adjacent single cells 10. Specific examples of the accommodating space 20 will be described in the following description.

[0040] In one embodiment, as an example, the limiting member 50 may include a plurality of first limiting strips 51, which may be, for example, glued to the large surface 11 of the battery cell. As an example, the first limiting strips 51 may be disposed along the outer edge of the large surface 11 to obtain a housing space 20 with the largest possible volume and to prevent the outflow of cooling medium flowing into the housing space 20, thereby providing better isolation for adjacent battery cells 10. In this embodiment, the aforementioned outer edge includes the bottom outer edge and the side outer edge of the large surface 11.

[0041] Specifically, the aforementioned plurality of first limiting strips 51 can be connected end-to-end and arranged along the outer edge of the large surface, forming an opening 53 facing the cooling member 40, the opening 53 forming the aforementioned connecting path 30. More specifically, some of the plurality of first limiting strips 51 can be arranged with the head of the first first limiting strip 51 and the tail of the last first limiting strip 51 spaced apart, with the remaining first limiting strips 51 connected end-to-end, forming a U-shaped structure with the opening 53 facing the cooling member 40. In addition, the first limiting strips 51 can also be elastic.

[0042] According to the battery pack provided in the embodiments of this application, the limiting member 50 may further include at least two second limiting strips 52, which are located at the opening 53 and are spaced apart. In the embodiment, the aforementioned connecting path 30 is formed between adjacent second limiting strips 52, and the aforementioned connecting path 30 is also formed between adjacent first limiting strips 51 and second limiting strips 52. In the embodiment, the connecting path 30 is located at the top of the large surface 11. It should be noted that the top refers to the position of the large surface 11 near the cooling member 40. Here, the at least two second limiting strips 52 (e.g., two) can be spaced apart along a third direction Y, that is, the length direction mentioned above, to form a connecting path 30 between adjacent second limiting strips 52.

[0043] According to the battery pack provided in the embodiments of this application, since the accommodating space 20 is connected to the accommodating cavity through the connecting path 30, when the cooling medium flows into the accommodating space 20, it can exchange heat with the adjacent single cell 10 between the large surfaces 11, increasing the heat dissipation area of ​​the single cell 10. At the same time, it forms a "water"-like barrier for the adjacent single cell 10, so that the single cell 10 in thermal runaway can transfer less heat to the adjacent single cell 10, further improving the safety performance of the battery pack.

[0044] According to the battery pack provided in the embodiments of this application, the battery pack can improve the protection against thermal runaway by about 10 to 20%. In addition, even if thermal runaway does not occur in a single cell 10, the heat conducted to adjacent cells 10 is reduced because the accommodating space 20 enhances the heat dissipation capacity of the large surface 11 of the single cell 10.

[0045] In one embodiment, three first limiting strips 51 can be affixed to the three sides of the large surface 11, and then two first limiting strips 51 can be affixed to the remaining side (e.g., the top side). As an example, in one embodiment, two second limiting strips 52 can be affixed to the opening 53 to provide three intervals for the cooling medium to flow into the accommodating space 20, that is, to obtain three connecting paths 30.

[0046] In an embodiment, the battery pack may further include a heat insulation plate 61 disposed on two adjacent large surfaces 11, and a limiting member 50 is disposed between the heat insulation plate 61 and the adjacent large surface 11, the limiting member 50, the heat insulation plate 61 and the large surface 11 enclosing an accommodating space 20.

[0047] Furthermore, in an embodiment, a limiting member 50 is provided between the heat insulation plate 61 and another adjacent large surface 11. The limiting member 50, the heat insulation plate 61, and the other large surface 11 enclose an accommodating space 20. That is, the two adjacent large surfaces 11 are each provided with a limiting member 50, and the heat insulation plate 61 is disposed on these two limiting members 50, thereby defining two accommodating spaces 20 on both sides of the heat insulation plate 61.

[0048] In an embodiment, such as Figure 5 As shown, in this embodiment, in addition to providing limiting members 50 on two large surfaces 11 that are opposite to each other, a heat insulation plate 61 is provided between the two limiting members 50, so that a receiving space 20 is formed between the heat insulation plate 61, one limiting member 50 and one large surface 11, and another receiving space 20 is formed between the heat insulation plate 61, the other limiting member 50 and the other large surface 11. That is to say, due to the provision of the heat insulation plate 61, two receiving spaces 20 are formed between adjacent single cells 10.

[0049] According to the battery pack provided in the embodiments of this application, the above-mentioned connecting path 30 can be set on the side of the accommodating space 20 near the cover plate, that is, it is actually located at the top of the accommodating space 20. In this way, the cooling medium released from the cooling member 40 can flow downward under its own gravity and flow to the connecting path 30 and into the accommodating space 20. As mentioned in the above description, in the embodiments, the connecting path 30 located at the top of the accommodating space 20 can be defined by the first limiting strip 51 and the second limiting strip 52 located at the top of the large surface 11. The specific way to set the second limiting strip 52 can be, for example, by adhesive bonding. Here, another advantage of setting the connecting path 30 at the top of the accommodating space 20 is that it helps to prevent the glue used to bond the second limiting strip 52 and the first limiting strip 51 from flowing from the accommodating space 20 onto the large surface 11 of the individual battery 10.

[0050] Furthermore, in the embodiments, the first limiting strip 51 and the second limiting strip 52 can be made of elastic materials such as rubber or foam, thereby increasing the friction between individual cells 10 and improving the overall pack mode.

[0051] According to the battery pack provided in the embodiments of this application, the battery pack may further include a plurality of busbars 70 electrically connected to the plurality of individual battery cells 10, and a cooling member 40 abutting against the busbars 70. In the embodiments, the busbars 70 may be, for example, busbars, i.e., spools. In the embodiments, the cooling member 40 may abut against the busbars 70 from above, that is, against the side of the busbars 70 near the cover plate, to provide direct cooling to the busbars 70.

[0052] According to the battery pack provided in this application, the individual battery 10 may further include an explosion-proof valve 13. The explosion-proof valve 13 may be disposed on the side of the individual battery 10 near the cover plate. The cooling component 40 may have multiple through holes, which may also be used to avoid obstructing the opening of the explosion-proof valve 13, thereby preventing the cooling component 40 from hindering the opening of the explosion-proof valve 13. Figure 1 and Figure 2 In this embodiment, the busbars 70 can be arranged in rows along the width direction of the individual battery 10, and multiple rows can be arranged along the length direction of the individual battery 10. The explosion-proof valves 13 can also be arranged in rows along the width direction of the individual battery 10, and alternate with the aforementioned busbars 70 along the length direction of the individual battery 10. Therefore, in this embodiment, as an example, the cooling member 40 can be formed, for example, in a grid shape, having strip-shaped holes to avoid the explosion-proof valves 13, and using its strip-shaped portion to abut against the busbars 70.

[0053] According to the battery pack provided in the embodiments of this application, the battery pack may further include a cushioning member 80, which is disposed above the cooling member 40. In the embodiments, the battery pack may also have a cover plate, with the cushioning member 80 located between the cover plate and the cooling member 40, thereby preventing the cooling member 40 and the cover from being worn and causing the cooling plate to crack. In the embodiments, the cushioning member 80 may be, for example, foam attached to the upper side of the cooling member 40.

[0054] According to the battery pack provided in the embodiments of this application, it should be reiterated that, in these embodiments, the main function of the heat insulation plate 61 is to provide thermal insulation and ensure that it does not affect the temperature transfer between adjacent individual cells 10. The main function of the limiting member 50 is to increase the friction between the individual cells 10, improve the overall pack mode, and create accommodating spaces 20 between the individual cells 10, ensuring that the individual cells have space for cyclic expansion. Another function of the accommodating spaces 20 is to allow the cooling medium (i.e., coolant) to flow from these accommodating spaces 20 to the large surface 11 of the individual cells 10. The accommodating spaces 20 also enhance the heat dissipation capacity of the individual cells 10.

[0055] In the embodiments, for single-cell batteries 10 with relatively low energy density or runaway temperatures below 500°C, such as single-cell batteries 10 with lithium iron phosphate cathode materials, the battery pack according to the embodiments of this application improves the protection capability against thermal runaway of single-cell batteries 10 by about 10 to 20%. This improvement in protection is based on the thermal insulation capability of the separator plate.

[0056] When dealing with individual cells 10 whose surface temperature (11) can exceed 500°C, such as those using medium-nickel or even high-nickel cathode materials, the heat insulation plate 61 provides basic thermal insulation, preventing the temperature of adjacent cells from rising rapidly. Meanwhile, the coolant flowing from the cooling component 40 sprays onto the runaway individual cell 10 for physical cooling, accelerating heat dissipation. The battery pack provided according to this embodiment improves heat dissipation capacity by approximately 20-30% by increasing the contact area between the coolant and the individual cell 10, thereby improving overall protection performance by approximately 10-20%. The coolant can flow onto the surface 11 of the cell through the gaps in the limiting component 50 on the heat insulation plate 61, accelerating the heat absorption of the individual cell 10 and allowing it to cool down more quickly.

[0057] According to a second aspect of the embodiments of this application, an electrical device is provided, which includes the battery pack as described above and also has the beneficial effects as described above, which will not be repeated here. The electrical device may be, for example, a car.

[0058] The above are merely preferred embodiments of this application and do not limit the scope of protection of this application. Any equivalent structural transformations made based on the innovative concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the scope of protection of this application.

Claims

1. A battery pack, characterized in that, The battery pack includes: The box (90) has a receiving cavity (91) inside. Multiple individual battery cells (10) are disposed within the receiving cavity (91). A cover plate, which is connected to the housing (90) and covers the receiving cavity (91). A cooling member (40) is disposed on the side of the plurality of individual cells (10) near the cover plate. A cooling medium flows through the cooling member (40). The cooling member (40) is configured to undergo a phase change at a predetermined temperature to release the cooling medium to the individual cells (10).

2. The battery pack according to claim 1, characterized in that, The single cell (10) includes a large surface (11), and there is an accommodating space (20) between the large surfaces (11) of two adjacent single cells (10), wherein the large surface (11) is the surface with the largest outer surface area on the single cell (10); The battery pack includes a limiting member (50) that abuts against the large surface (11) of two adjacent individual batteries (10), and the limiting member (50) and the adjacent large surface (11) enclose and define the accommodating space (20). The limiting member (50) has a connecting path (30) that connects the accommodating space (20) and the accommodating cavity (91).

3. The battery pack according to claim 2, characterized in that, The limiting member (50) includes a plurality of first limiting strips (51), which are connected end to end and form an opening (53) facing the cooling member (40). The opening (53) forms the connecting path (30), and the first limiting strips (51) are elastic.

4. The battery pack according to claim 3, characterized in that, The limiting member (50) includes at least two second limiting strips (52), which are located at the opening (53) and spaced apart, forming the connecting path (30) between two adjacent second limiting strips (52) and between adjacent first limiting strips (51) and second limiting strips (52), and the second limiting strips (52) are elastic.

5. The battery pack according to claim 2, characterized in that, The battery pack also includes a heat insulation plate (61) disposed between two adjacent large surfaces (11), and a limiting member is disposed between the heat insulation plate (61) and an adjacent large surface (11), the limiting member, the heat insulation plate (61) and the large surface (11) enclosing an accommodating space (20).

6. The battery pack according to claim 5, characterized in that, The limiting member is provided between the heat insulation plate (61) and the adjacent large surface (11), and the limiting member, together with the heat insulation plate (61) and the other large surface (11), encloses a receiving space (20).

7. The battery pack according to any one of claims 1 to 6, characterized in that, The battery pack also includes a plurality of busbars (70) electrically connected to the plurality of individual cells (10), and the cooling member (40) abuts against the side of the busbars (70) near the cover plate.

8. The battery pack according to claim 7, characterized in that, The single cell (10) also includes an explosion-proof valve (13), which is disposed on the side of the single cell near the cover plate. The cooling component (40) has multiple through holes for avoiding the explosion-proof valve (13).

9. The battery pack according to any one of claims 1 to 6, characterized in that, The battery pack also includes a buffer member (80) disposed between the cooling member (40) and the cover plate.

10. An electrical appliance, characterized in that, The electrical device includes a battery pack as claimed in any one of claims 1 to 9.

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