Battery pack

Abstract

The utility model relates to the technical field of batteries, in particular to a battery pack which comprises a battery box body, cylindrical batteries, a cooling plate and a heating film, the cylindrical battery is arranged in the battery box body, the axial direction of the cylindrical battery is a first direction, the cylindrical battery is provided with a first end surface, a second end surface and an outer ring surface, the first end surface and the second end surface are arranged at an interval in the first direction, and the outer ring surface is connected between the first end surface and the second end surface; the cooling plate is provided with a first surface facing the first end face; the heating film is arranged on the first surface and located between the cooling plate and the first end face. The heating film is provided with a penetrating structure penetrating in the thickness direction. On a reference plane parallel to the first surface, the orthographic projection pattern of the first end face and the orthographic projection pattern of the penetrating structure are at least partially overlapped, and the penetrating structure is suitable for being in heat conduction connection with the first end face and the cooling plate.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery pack. Background Art

[0002] In the existing design of battery packs, some battery packs adopt the design of heat exchange between the end face of the cylindrical battery and the cooling plate, that is, the cooling plate has a heat exchange surface facing the end face of the cylindrical battery. In addition, the heat exchange surface of the cooling plate is covered with a heating film to achieve heating of the cylindrical battery. However, due to the setting of the heating film, the heat transfer effect between the cylindrical battery and the cooling plate is poor, which affects the cooling effect of the cooling plate. Utility Model Content

[0003] A main purpose of the present invention is to overcome at least one defect of the above-mentioned prior art and provide a battery pack with high heat transfer efficiency between the cooling plate and the cylindrical battery.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] According to one aspect of the utility model, a battery pack is provided, which includes a battery case, a cylindrical battery, a cooling plate and a heating film; the cylindrical battery is arranged in the battery case, and its axial direction is a first direction, the cylindrical battery has a first end face, a second end face and an outer annular surface, the first end face and the second end face are arranged at intervals in the first direction, and the outer annular surface is connected between the first end face and the second end face; the cooling plate has a first surface facing the first end face; the heating film is arranged on the first surface and is located between the cooling plate and the first end face, and the heating film has a penetrating structure penetrating along the thickness direction; wherein, on a reference plane parallel to the first surface, the orthographic projection figure of the first end face and the orthographic projection figure of the penetrating structure at least partially overlap, and the penetrating structure is suitable for providing a thermal connection between the first end face and the cooling plate.

[0006] It can be seen from the above technical solutions that the advantages and positive effects of the battery pack proposed by the utility model are:

[0007] The battery pack proposed by the utility model adopts a design in which the first surface of the heating film faces the first end face of the cylindrical battery; a heating film is arranged on the first surface of the cooling plate, and the heating film is located between the cooling plate and the first end face and is provided with a through structure penetrating along the thickness direction; on a reference plane parallel to the first surface, the orthographic projection figure of the first end face and the orthographic projection figure of the through structure at least partially overlap, and the through structure is suitable for providing a thermal connection between the first end face and the cooling plate. Through the above structural design, the utility model can use the through structure to reduce the influence of the heating film on the heat transfer between the cooling plate and the cylindrical battery, and can realize direct heat transfer between the cooling plate and the cylindrical battery via the through structure, thereby improving the heat transfer efficiency and optimizing the thermal performance of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The various objects, features and advantages of the present invention will become more apparent by considering the following detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. The accompanying drawings are only exemplary illustrations of the present invention and are not necessarily drawn to scale. In the accompanying drawings, the same reference numerals always represent the same or similar parts. Among them:

[0009] Figure 1 is a schematic diagram of a three-dimensional structure of a battery pack according to an exemplary embodiment;

[0010] Figure 2 yes Figure 1 An enlarged schematic diagram of part A in FIG.

[0011] Figure 3 yes Figure 1 A schematic diagram of a three-dimensional structure of a partial structure of a battery pack is shown;

[0012] Figure 4 yes Figure 3 Schematic diagram of the three-dimensional decomposition of

[0013] Figure 5 yes Figure 4 A schematic diagram of the orthographic projection of the penetration structure and the first end surface of the cylindrical battery on the reference plane;

[0014] Figure 6 yes Figure 4 A schematic plan view of the heating film shown;

[0015] Figure 7 yes Figure 3 Schematic diagram of a local cross section.

[0016] The following are the descriptions of the reference numerals:

[0017] 100. Battery box;

[0018] 110. Bottom plate;

[0019] 1101. Module base plate;

[0020] 200. Cylindrical battery;

[0021] 201. Battery column;

[0022] 202. Battery pack;

[0023] 210. First end surface;

[0024] 220. Second end surface;

[0025] 220. Outer annulus;

[0026] 230. Explosion-proof valve;

[0027] 300. Cooling plate;

[0028] 310. First surface;

[0029] 400. Heating film;

[0030] 410.Throughout structure;

[0031] 500. Conductive bar;

[0032] 610. First adhesive layer;

[0033] 620. Second adhesive layer;

[0034] D. Spacing;

[0035] O. Center of circle;

[0036] X. First direction;

[0037] Y. Second direction;

[0038] Z. Third direction. DETAILED DESCRIPTION

[0039] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and drawings therein are essentially for illustrative purposes rather than for limiting the present invention.

[0040] In the following description of different exemplary embodiments of the utility model, reference is made to the accompanying drawings, which form a part of the utility model and in which different exemplary structures, systems and steps that can implement multiple aspects of the utility model are shown by way of example. It should be understood that other specific schemes of components, structures, exemplary devices, systems and steps can be used, and structural and functional modifications can be made without departing from the scope of the utility model. Moreover, although the terms "above", "between", "within", etc. can be used in this specification to describe different exemplary features and elements of the utility model, these terms are used herein only for convenience, such as according to the direction of the examples described in the accompanying drawings. Nothing in this specification should be construed as requiring a specific three-dimensional orientation of the structure to fall within the scope of the utility model.

[0041] See also Figure 1 , which representatively shows a three-dimensional structural schematic diagram of the battery pack proposed by the utility model. In this exemplary embodiment, the battery pack proposed by the utility model is described by taking a vehicle-mounted battery as an example. It is easy for those skilled in the art to understand that in order to apply the relevant design of the utility model to other types of battery devices, various modifications, additions, substitutions, deletions or other changes are made to the specific embodiments described below, and these changes are still within the scope of the principle of the battery pack proposed by the utility model.

[0042] like Figure 1 As shown, in one embodiment of the present invention, the battery pack provided by the present invention includes a battery box 100, a cylindrical battery 200, a cooling plate 300 and a heating film 400. Figures 2 to 7 , Figure 2 Representatively shown in Figure 1 An enlarged schematic diagram of part A in FIG. Figure 3 , a three-dimensional schematic diagram of a partial structure of a battery pack is representatively shown, wherein a combined structure of a bottom plate 110, a cooling plate 300, a heating film 400 and a part of a cylindrical battery 200 is specifically shown; Figure 4 Representatively shown in Figure 3 Schematic diagram of the three-dimensional decomposition of Figure 5 , which is a representative diagram showing the orthographic projection of the through structure 410 and the first end surface 210 of the cylindrical battery 200 on the reference plane; Figure 6 A schematic plan view of the heating film 400 is representatively shown in FIG. Figure 7 Representatively shown in Figure 3 The following will describe in detail the structure, connection mode and functional relationship of the main components of the battery pack proposed by the utility model in combination with the above-mentioned drawings.

[0043] like Figures 1 to 6As shown, in one embodiment of the present invention, a cylindrical battery 200 is disposed in a battery box 100, and the cylindrical battery 200 has a first end face 210, a second end face 220 and an outer annular surface 230, and the first end face 210 and the second end face 220 are arranged at intervals in a first direction X, and the first direction X is the axial direction of the cylindrical battery 200, and the outer annular surface 230 is connected between the first end face 210 and the second end face 220. The cooling plate 300 has a first surface 310 facing the first end face 210, that is, the cooling plate 300 is facing the first end face 210 of the cylindrical battery 200 with its first surface 310, and the first surface 310 and the first end face 210 can be parallel. Among them, the cooling plate 300 contacts and exchanges heat with the first end face 210 of the cylindrical battery 200 (can be direct contact, or can be indirect contact through other structures, such as the first adhesive layer 610, etc.). The heating film 400 is disposed on the first surface 310 of the cooling plate 300 and is located between the cooling plate 300 and the first end surface 210 of the cylindrical battery 200, and the heating film 400 has a through structure 410, which penetrates the heating film 400 along the thickness direction (e.g., the first direction X) of the heating film 400. On this basis, on a reference plane parallel to the first surface 310, the orthographic projection figure of the first end surface 210 and the orthographic projection figure of the through structure 410 at least partially overlap, and the through structure 410 is suitable for providing a thermal connection between the first end surface 210 of the cylindrical battery 200 and the cooling plate 300. Through the above structural design, the utility model can use the through structure 410 to reduce the influence of the heating film 400 on the heat transfer between the cooling plate 300 and the cylindrical battery 200, and can realize direct heat transfer between the cooling plate 300 and the cylindrical battery 200 through the through structure 410, thereby improving the heat transfer efficiency and optimizing the thermal performance of the battery pack.

[0044] like Figure 6 As shown, in one embodiment of the present invention, the heating film 400 is provided with at least two penetration structures 410. On the above-mentioned reference plane, the orthographic projection figure of each penetration structure 410 only overlaps at least partially with the orthographic projection figure of the first end face 210 of one cylindrical battery 200. Through the above-mentioned structural design, the present invention is suitable for increasing the bonding and positioning effect between the cylindrical battery 200 and the cooling plate 300 by applying glue at fixed points in the penetration structure 410, thereby strengthening the limiting fixation between each cylindrical battery 200.

[0045] like Figure 5As shown, based on the structural design that the heating film 400 is provided with at least two through structures 410, in one embodiment of the utility model, the ratio of the area of ​​the orthographic projection figure of the through structure 410 to the area of ​​the orthographic projection figure of the first end face 210 of the cylindrical battery 200 can be 0.047-0.253, such as 0.047, 0.075, 0.1, 0.2, 0.253, etc. Through the above structural design, since the heat transfer efficiency of the cylindrical battery 200 in the axial direction is much greater than its heat transfer efficiency in the radial direction, there needs to be an area on the first end face 210 of the cylindrical battery 200 that fits with the heating film 400, that is, the area of ​​the through structure 410 is smaller than the area of ​​the first end face 210, thereby improving the heat transfer efficiency of the cylindrical battery 200 in its radial direction.

[0046] In one embodiment of the present invention, the area of ​​the orthographic projection of the through structure 410 can be 78 mm 2 ~420mm 2 , for example 78mm 2 , 100mm 2 、150mm 2 、300mm 2 、420mm 2 wait.

[0047] like Figure 5 As shown, based on the structural design of the above-mentioned area relationship between the through structure 410 and the orthographic projection figure of the first end face 210, in one embodiment of the present utility model, on the above-mentioned reference plane, the geometric center of the orthographic projection figure of the first end face 210 and the geometric center of the orthographic projection figure of the through structure 410 can coincide. Taking the orthographic projection figures of the first end face 210 and the through structure 410 as an example, the above-mentioned geometric center can be understood as the center O of the corresponding circle of the orthographic projection figure. Through the above-mentioned structural design, the utility model can ensure that the radial dimensions of the thermal connection between the cylindrical battery 200 and the heating film 400 are consistent at all points within the circumference, so that the heat transfer effect of the cylindrical battery 200 in the radial direction is more uniform, which is conducive to the thermal balance of the monomer.

[0048] like Figure 6As shown, based on the structural design that the heating film 400 is provided with at least two through structures 410, in one embodiment of the present utility model, for any two adjacent through structures 410 on the heating film 400, the distance D between the two can be 20mm to 48mm, such as 20mm, 25mm, 30mm, 40mm, 48mm, etc. It should be noted that the so-called distance D between the two through structures 410 can be a line drawn between the geometric centers (such as the center of the circle O) of the orthographic projection figures of the two through structures 410 on the above-mentioned reference plane, and the length of the part of the line located outside the contours of the two orthographic projection figures is the above-mentioned distance D. Through the above-mentioned structural design, the utility model can be suitable for the space arrangement form in which the cylindrical batteries 200 are arranged in a relatively compact manner, which is conducive to improving the space utilization rate, and at the same time can avoid the too small distance between the through structures 410, which makes the heating core more easily damaged and ineffective. In some embodiments, the distance D between two adjacent through structures 410 may be less than 20 mm, or may be greater than 48 mm, such as 19.5 mm, 49 mm, etc., and is not limited to this embodiment.

[0049] like Figure 6 As shown, in one embodiment of the present invention, on the above-mentioned reference plane, the area of ​​the orthographic projection figure of the penetration structure 410 can account for 5% to 20% of the area of ​​the orthographic projection figure of the heating film 400, such as 5%, 7%, 10%, 15%, 20%, etc. It should be noted that the area of ​​the orthographic projection figure of the above-mentioned heating film 400 refers to the area of ​​the figure surrounded by the outer contour of the orthographic projection figure of the heating film 400, that is, the area includes the area of ​​the orthographic projection figure of all the penetration structures 410. Through the above-mentioned structural design, the present invention can avoid the area of ​​the penetration structure 410 from accounting for too large a proportion. Since the thickness of the heating film 400 itself is relatively thin, the area of ​​the penetration structure 410 is too large, which will lead to poor strength of the heating film 400 and make it more easily damaged during the assembly process. At the same time, the present invention can avoid the area of ​​the penetration structure 410 from accounting for too small a proportion, thereby ensuring the effect of strengthening heat transfer and fixation. In some embodiments, the proportion of the through structure 410 in the area of ​​the orthographic projection pattern of the heating film 400 may be less than 5%, or may be greater than 20%, such as 4.9%, 21%, etc., which is not limited to this embodiment.

[0050] like Figure 7 As shown, in one embodiment of the present invention, the battery pack proposed by the present invention may further include a heat conductor, which is at least partially arranged in the through structure 410, accordingly, the first end face 210 of the cylindrical battery 200 and the cooling plate 300 are thermally connected via the heat conductor.

[0051] like Figure 7As shown, in one embodiment of the present invention, the heat conductive member may include a first adhesive layer 610, at least a portion of which is suitable for bonding the cylindrical battery 200 and the cooling plate 300. Through the above structural design, the present invention can use the first adhesive layer 610 to achieve a fixed connection between the cylindrical battery 200 and the cooling plate 300. Further, the first adhesive layer 610 can be made of a heat conductive structural adhesive, thereby taking into account both the fixed positioning of the cylindrical battery 200 and the cooling plate 300 and the heat transfer performance between the cylindrical battery 200 and the cooling plate 300.

[0052] like Figure 7 As shown, based on the structural design that the first adhesive layer 610 is provided in the through structure 410, in one embodiment of the present utility model, at least a portion of the first adhesive layer 610 is suitable for simultaneously bonding the cylindrical battery 200, the cooling plate 300 and the heating film 400. For example, the first adhesive layer 610 can be bonded to at least a portion of the inner edge of the through structure 410. Through the above structural design, the utility model can further realize the fixed connection of the cylindrical battery 200, the cooling plate 300 and the heating film 400 by using the first adhesive layer 610. In some embodiments, the first adhesive layer 610 may also be only suitable for bonding the cylindrical battery 200 and the cooling plate 300, that is, the first adhesive layer 610 and the heating film 400 (for example, the inner edge of the through structure 410) may also have no bonding relationship, and is not limited to this embodiment.

[0053] like Figure 7 As shown, based on the structural design that the first adhesive layer 610 simultaneously bonds the cylindrical battery 200, the cooling plate 300 and the heating film 400, in one embodiment of the utility model, a second adhesive layer 620 may be provided between the cooling plate 300 and the heating film 400, and the second adhesive layer 620 is suitable for bonding the cooling plate 300 and the heating film 400. On this basis, the bonding strength of the second adhesive layer 620 may be less than the bonding strength of the first adhesive layer 610. Through the above structural design, since the second adhesive layer 620 between the heating film 400 and the cooling plate 300 is relatively weak, and when the heating film 400 is provided with a through structure 410, the cylindrical battery 200, the cooling plate 300 and the heating film 400 are bonded simultaneously through the first adhesive layer 610, the fixed connection effect between the above three is increased, and the contact is ensured at the same time, which also ensures heat conduction. At the same time, by utilizing the difference in bonding strength between the first adhesive layer 610 and the second adhesive layer 620, when the cylindrical battery 200 and the cooling plate 300 are misaligned due to vibration conditions or battery expansion, it is suitable to achieve that the second adhesive layer 620 with weaker bonding strength is first broken to contact the bonding of the cooling plate 300 and the heating film 400, thereby avoiding excessive shear force on the heating film 400, which may cause the heating film 400 to leak out of the heating core.

[0054] like Figure 5As shown, in one embodiment of the present invention, on the above-mentioned reference plane, the orthographic projection figure of the penetration structure 410 can be a circle. In some embodiments, the orthographic projection figure of the penetration structure 410 can also be other shapes, such as a rectangle, etc., which is not limited to this embodiment.

[0055] It should be noted that Figures 4 to 6 In the illustrated embodiment, the through structure 410 is taken as an example of a through hole. It should be understood that in some embodiments, the through structure 410 may also be a notch, one side of which opens to the edge of the heating film 400, and is not limited to the above embodiment.

[0056] In one embodiment of the present invention, a core and a heating wire are disposed in the heating film 400 , and the core and the heating wire are arranged around the through structure 410 .

[0057] In one embodiment of the present invention, the first end surface 210 of the cylindrical battery 200 may be provided with an insulating layer. Through the above structural design, the present invention can use the insulating layer to ensure the insulation performance between the first end surface 210 and the cooling plate 300.

[0058] Based on the structural design that the first end surface 210 is provided with an insulating layer, in one embodiment of the utility model, the insulating layer may be an insulating spray layer. Through the above design, since the insulating spray layer has a greater surface roughness than insulating layers of other structural forms (such as insulating films), the utility model can further improve the bonding strength between the cooling plate 300 or the heating film 400 and the cylindrical battery 200 by using the design of the insulating spray layer.

[0059] like Figure 2 As shown, in one embodiment of the present invention, the second end surface 220 of the cylindrical battery 200 may be connected to a conductive bar 500. Through the above structural design, the present invention can avoid the cooling plate 300 being connected to the second end surface 220 of the cylindrical battery 200 and interfering with the conductive bar 500.

[0060] like Figure 3 and Figure 4 As shown, in one embodiment of the present invention, the second end face 220 of the cylindrical battery 200 may be provided with an explosion-proof valve 230. Through the above structural design, the present invention can avoid the problem that the cooling plate 300 blocks the pressure relief spray valve when the explosion-proof valve 230 is provided on the first end face 210.

[0061] like Figure 2 and Figure 3As shown, in one embodiment of the present invention, the battery case 100 includes a bottom plate 110, the axial direction of the cylindrical battery 200 is parallel to the bottom plate 110, that is, the first direction X is parallel to the bottom plate 110, and the first surface 310 of the cooling plate 300 is perpendicular to the bottom plate 110. In other words, the cylindrical battery 200 is arranged in a "lying" manner, and the so-called "lying" is relative to the bottom plate 110, and the cooling plate 300 is arranged in a "standing" manner relative to the bottom plate 110. On this basis, at least two cylindrical batteries 200 are arranged into a battery column 201 along the second direction Y, and the second direction Y is parallel to the bottom plate 110 and parallel to the first surface 310 of the cooling plate 300, and the battery column 201 is arranged on both sides of the cooling plate 300 in the first direction X.

[0062] like Figure 2 and Figure 3 As shown, based on the structural design that at least two cylindrical batteries 200 are arranged in a battery column 201 along the second direction Y, in one embodiment of the present invention, the battery pack proposed by the present invention may include at least two battery columns 201, and at least two battery columns 201 are arranged in a battery group 202 along a third direction Z, and the third direction Z is perpendicular to the bottom plate 110. Through the above structural design, the present invention can make full use of the internal space of the battery box 100 to arrange the cylindrical batteries 200, which is conducive to improving the energy density of the battery pack. In a common use scenario, the vibration of the battery pack in the third direction Z will be more frequent than the vibration in the first direction X and the second direction Y. When the battery pack vibrates in the third direction Z, the thermal contact between the cylindrical battery 200 and the cooling plate 300 is more likely to fail. In this regard, the present invention uses a heating film 400 to set a through structure 410, which can increase the fixing strength between the cylindrical battery 200 with a "lying" design and the cooling plate 300 with a "standing" design, and improve the mode of the battery pack in the third direction Z.

[0063] like Figure 2 and Figure 3 As shown, based on the structural design that at least two battery columns 201 are arranged along the third direction Z to form a battery group 202, in one embodiment of the present utility model, the battery pack proposed by the present utility model may include at least two battery groups 202, and at least two battery groups 202 are arranged along the first direction X. On this basis, the two battery groups 202 can be respectively located on both sides of the cooling plate 300 in the first direction X, that is, the two first surfaces 310 of the cooling plate 300 can respectively face the first end surfaces 210 of the cylindrical batteries 200 of the two battery groups 202 on both sides. Through the above structural design, the utility model can use the cooling plate 300 to achieve contact heat exchange with the cylindrical batteries 200 of the two adjacent battery groups 202, which is conducive to reducing the number of components and simplifying the complexity of the structure.

[0064] In one embodiment of the present invention, the cylindrical battery 200 may be a lithium iron battery. For example, the positive electrode active material of the cylindrical battery 200 may be lithium iron phosphate.

[0065] It should be noted that Figure 1 Taking the illustrated embodiment as an example, when cylindrical batteries 200 are provided on both sides of the cooling plate 300 in the first direction X, the cooling plate 300 and the cylindrical batteries 200 on both sides and other related structures can together constitute a battery module, and the battery module can be arranged on the module bottom plate 1101, and arranged on the bottom plate 110 of the battery box via the module bottom plate 1101. At this time, the relative arrangement relationship between each structure and the bottom plate 110 in this specification can be correspondingly understood as the relative arrangement relationship between each structure and the module bottom plate 1101. Through the above-mentioned structural design, the utility model can improve the integration of the battery module, which is conducive to improving the assembly efficiency. It should be understood that in some embodiments, the battery pack may not be provided with a module bottom plate 1101, and the battery module may also be directly arranged on the bottom plate 110 of the battery box 100.

[0066] It should be noted that the battery packs shown in the drawings and described in this specification are only a few examples of many types of battery packs that can adopt the principles of the present invention. It should be clearly understood that the principles of the present invention are by no means limited to any details of the battery packs shown in the drawings or described in this specification or any components of the battery packs.

[0067] In summary, the battery pack proposed by the present invention adopts a design in which the first surface 310 of the heating film 400 faces the first end face 210 of the cylindrical battery 200; the heating film 400 is provided on the first surface 310 of the cooling plate 300, and the heating film 400 is located between the cooling plate 300 and the first end face 210 and is provided with a through structure 410 that penetrates along the thickness direction; on a reference plane parallel to the first surface 310, the orthographic projection figure of the first end face 210 and the orthographic projection figure of the through structure 410 at least partially overlap, and the through structure 410 is suitable for providing a thermal connection between the first end face 210 and the cooling plate 300. Through the above structural design, the present invention can use the through structure 410 to reduce the influence of the heating film 400 on the heat transfer between the cooling plate 300 and the cylindrical battery 200, and can realize direct heat transfer between the cooling plate 300 and the cylindrical battery 200 via the through structure 410, thereby improving the heat transfer efficiency and optimizing the thermal performance of the battery pack.

[0068] The exemplary embodiments of the battery pack proposed by the utility model are described and / or illustrated in detail above. However, the embodiments of the utility model are not limited to the specific embodiments described here. On the contrary, the components and / or steps of each embodiment can be used independently and separately from other components and / or steps described here. Each component and / or each step of an embodiment can also be used in combination with other components and / or steps of other embodiments. When introducing the elements / components / etc. described and / or illustrated here, the terms "one", "one" and "above" are used to indicate the presence of one or more elements / components / etc. The terms "comprising", "including" and "having" are used to express the meaning of open inclusion and mean that in addition to the listed elements / components / etc., there may be additional elements / components / etc. In addition, the terms "first" and "second" in the claims and the specification are used only as marks and are not numerical restrictions on their objects.

[0069] Although the battery pack of the present invention has been described according to different specific embodiments, those skilled in the art will recognize that the implementation of the present invention can be modified within the spirit and scope of the claims.

Claims

1. A battery pack, characterized in that: include: Battery box; A cylindrical battery is arranged in the battery box, and its axial direction is a first direction. The cylindrical battery has a first end face, a second end face and an outer annular surface. The first end face and the second end face are arranged at intervals in the first direction, and the outer annular surface is connected between the first end face and the second end face; a cooling plate having a first surface facing the first end surface; A heating film, disposed on the first surface and located between the cooling plate and the first end surface, the heating film having a penetrating structure penetrating along a thickness direction; Among them, on a reference plane parallel to the first surface, the orthographic projection pattern of the first end face and the orthographic projection pattern of the penetrating structure at least partially overlap, and the penetrating structure is suitable for thermally connecting the first end face and the cooling plate.

2. The battery pack according to claim 1, characterized in that: The heating film is provided with at least two of the penetration structures. On the reference plane, the orthographic projection pattern of each of the penetration structures at least partially overlaps with the orthographic projection pattern of the first end surface of only one of the cylindrical batteries.

3. The battery pack according to claim 2, characterized in that: The ratio of the area of ​​the orthographic projection figure of the penetration structure to the area of ​​the orthographic projection figure of the first end surface of the cylindrical battery is 0.047 to 0.

253.

4. The battery pack according to claim 3, characterized in that: The area of ​​the orthographic projection of the through structure is 78 mm 2 ~420mm 2 .

5. The battery pack according to claim 3, characterized in that: On the reference plane, the geometric center of the orthographic projection figure of the first end surface coincides with the geometric center of the orthographic projection figure of the penetrating structure.

6. The battery pack according to claim 2, characterized in that: The distance between two adjacent through structures is 20 mm to 48 mm.

7. The battery pack according to claim 1, characterized in that: On the reference plane, the area of ​​the orthographic projection figure of the penetration structure accounts for 5% to 20% of the area of ​​the figure enclosed by the outer contour of the orthographic projection figure of the heating film.

8. The battery pack according to any one of claims 1 to 7, characterized in that: The battery pack further includes a heat conductive member, which is at least partially disposed in the through structure, and the first end surface is thermally connected to the cooling plate via the heat conductive member.

9. The battery pack according to claim 8, characterized in that: The heat conductive member includes a first adhesive layer, at least a portion of which is suitable for bonding the cylindrical battery and the cooling plate.

10. The battery pack according to claim 9, characterized in that: At least a portion of the first adhesive layer is suitable for simultaneously bonding the cylindrical battery, the cooling plate and the heating film.

11. The battery pack according to claim 10, characterized in that: A second adhesive layer is provided between the cooling plate and the heating film, and the second adhesive layer is suitable for bonding the cooling plate and the heating film; wherein the bonding strength of the second adhesive layer is less than the bonding strength of the first adhesive layer.

12. The battery pack according to any one of claims 1 to 7, characterized in that: The battery case includes a bottom plate; wherein the axial direction of the cylindrical battery is parallel to the bottom plate, and the first surface of the cooling plate is perpendicular to the bottom plate; wherein at least two of the cylindrical batteries are arranged into a battery column along a second direction, the second direction is parallel to the bottom plate and parallel to the first surface, and the battery column is provided on at least one side of the cooling plate in the first direction.

13. The battery pack according to claim 12, characterized in that: At least two of the battery columns are arranged along a third direction to form a battery group, and the third direction is perpendicular to the bottom plate.

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