Battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery pack which can comprise a battery box, a battery pack and a heat exchange assembly, the battery box comprises a box wall; the battery pack is arranged in the battery box, the battery pack comprises at least two single batteries, and a pressure relief space is arranged between the single batteries and the box wall; the heat exchange assembly comprises a first heat exchange plate and a heat exchange fin, the first heat exchange plate is arranged between two adjacent single batteries and is in heat exchange contact with the two adjacent single batteries, the heat exchange fin is connected to one end, close to the pressure relief space, of the first heat exchange plate, the heat exchange fin is located in the pressure relief space, and at least part of the heat exchange fin extends to the box wall; the heat exchange fins extend in the first direction to divide the pressure relief space into two pressure relief sub-spaces, and one pressure relief sub-space is arranged opposite to at least one single battery. The battery pack is high in heat exchange efficiency, and when one single battery is overheated, the influence on the adjacent single battery is small.

Description

Technical Field

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

[0002] When the single cells in the battery pack overheat, the overheated gas is discharged to the pressure relief space through the pressure relief valve, and then discharged out of the battery pack through the pressure relief space, so as to prevent the overheated gas from affecting other single cells in the battery pack.

[0003] However, currently, since the pressure relief space is connected to all the single cells, when one single cell overheats, the overheated gas ejected through the pressure relief valve will still affect the adjacent single cells.

[0004] It should be noted that the information disclosed in the above background art section is only used to enhance the understanding of the background of the present disclosure, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Utility Model

[0005] The purpose of the present disclosure is to overcome the deficiencies of the above related technologies and provide a battery pack.

[0006] According to one aspect of the present disclosure, there is provided a battery pack, including:

[0007] A battery box, including a box wall;

[0008] A battery pack, disposed in the battery box, the battery pack including at least two single cells, and a pressure relief space is provided between the single cells and the box wall;

[0009] A heat exchange assembly, including a first heat exchange plate and heat exchange fins, the first heat exchange plate is disposed between two adjacent single cells and is in heat exchange contact with the two adjacent single cells, the heat exchange fins are connected to one end of the first heat exchange plate close to the pressure relief space, the heat exchange fins are located in the pressure relief space, and at least part of the heat exchange fins extends to the box wall, and the heat exchange fins extend along a first direction to divide the pressure relief space into two sub-pressure relief spaces, and one of the sub-pressure relief spaces is disposed opposite to at least one of the single cells.

[0010] In the battery pack of the present disclosure, at least a part of the heat exchange fins extends to the box wall, and the heat exchange fins extend in a first direction to divide the pressure relief space into two sub-pressure relief spaces. On the one hand, the adjacent sub-pressure relief spaces of two single cells can be isolated by the heat exchange fins so that they are not connected, avoiding the influence on the adjacent single cell in the case that one single cell overheats and ejects overheated gas. On the other hand, the heat exchange fins can cool the ejected overheated gas, further reducing the influence of the overheated gas on the adjacent single cell and enhancing the safety performance of the battery pack.

[0011] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure. Obviously, the accompanying drawings in the following description are only some embodiments of the present disclosure, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0013] Figure 1 It is a schematic structural diagram of an exemplary embodiment of the battery device of the present disclosure.

[0014] Figure 2 It is a schematic structural diagram of the cooperation of a group of battery packs, a heat exchange component and a support structure in an exemplary embodiment of the battery device of the present disclosure.

[0015] Figure 3 It is a three-dimensional structural diagram of the cooperation of a group of battery packs, a heat exchange component and a support structure in another exemplary embodiment of the battery device of the present disclosure.

[0016] Figure 4 is Figure 3 a bottom-up three-dimensional structural diagram of the cooperation of a group of battery packs and a heat exchange component in

[0017] DESCRIPTION OF REFERENCE NUMERALS:

[0018] 1, battery box; 1a, box wall; 1a1, groove; 11, first side frame; 12, second side frame; 13, bottom plate;

[0019] 20, battery pack; 201, battery row; 2, single cell; 2a, electrode lead-out end; 2b, pressure relief end; 21, cover plate; 22, bottom wall; 221, pressure relief valve; 23, battery pole column;

[0020] 3, pressure relief space; 31, sub-pressure relief space; 32, air flow channel;

[0021] 4. Heat exchange assembly; 41. First heat exchange plate; 411. First sub-heat exchange plate; 412. Second sub-heat exchange plate; 42. Heat exchange fins; 421. First part; 422. Second part; 42a. Main fins; 42b. Auxiliary fins; 42b1. First auxiliary fin; 42b2. Second auxiliary fin; 43. Second heat exchange plate;

[0022] 5. Support structure; 51. Support plate; 52. Connecting plate;

[0023] 6. Thermal conductive structural adhesive layer;

[0024] X. First direction; Y. Second direction; Z. Height direction. Detailed implementation manners

[0025] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. Like reference numerals in the figures denote the same or similar structures, and thus their detailed descriptions will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0026] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another component, these terms are used in this specification only for convenience, for example, according to the directions of the examples described in the accompanying drawings. It can be understood that if the device of the icon is turned upside down, the component described as "upper" will become the component described as "lower". When a structure is "on" another structure, it may mean that a structure is integrally formed on another structure, or that a structure is "directly" disposed on another structure, or that a structure is "indirectly" disposed on another structure through another structure.

[0027] The terms "a", "an", "the", "said" and "at least one" are used to indicate the existence of one or more elements / components / etc.; the terms "comprising" and "having" are used to mean an open inclusion and mean that there may be additional elements / components / etc. in addition to the listed elements / components / etc.; the terms "first", "second" and "third", etc. are only used as labels and are not a limitation on the quantity of their objects.

[0028] In this application, unless otherwise clearly specified and defined, the term "connection" shall be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral one; it can be directly connected or indirectly connected through an intermediate medium. "And / or" is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this text generally represents an "or" relationship between the associated objects before and after.

[0029] This exemplary embodiment of the present disclosure provides a battery pack. Referring to Figures 1 - 4 As shown, the battery pack may include a battery box 1, a battery pack 20, and a heat exchange component 4; the battery box 1 may include a box wall 1a; the battery pack 20 is disposed in the battery box 1, and the battery pack 20 may include at least two single cells 2. A pressure relief space 3 is provided between the single cell 2 and the box wall 1a; the heat exchange component 4 may include a first heat exchange plate 41 and heat exchange fins 42. The first heat exchange plate 41 is disposed between two adjacent single cells 2 and is in heat exchange contact with the two adjacent single cells 2. The heat exchange fins 42 are connected to one end of the first heat exchange plate 41 close to the pressure relief space 3. The heat exchange fins 42 are located in the pressure relief space 3, and at least part of the heat exchange fins 42 extend to the box wall 1a. The heat exchange fins 42 extend along the first direction X to divide the pressure relief space 3 into two sub-pressure relief spaces 31, and one sub-pressure relief space 31 is disposed opposite to at least one single cell 2.

[0030] For the battery pack of the present disclosure, on the one hand, the heat exchange fins 42 can isolate the sub-pressure relief spaces 31 of two adjacent single cells 2 so that they are not connected, avoiding the influence on adjacent single cells 2 in the case that one single cell 2 overheats and ejects overheated gas; on the other hand, the heat exchange fins 42 can cool the ejected overheated gas, further reducing the influence of the overheated gas on adjacent single cells 2 and enhancing the safety performance of the battery pack.

[0031] The battery box 1 includes a box wall 1a, and the box wall 1a is used to support the battery pack 20. In this exemplary embodiment, referring to Figure 1As shown, the battery pack may include a battery box 1, and the battery box 1 may be configured in a cuboid structure. Specifically, the battery box 1 may include a bottom plate 13, a protective cover (not shown in the figure), two first side frames 11, and two second side frames 12. The bottom plate 13 and the protective cover may be configured as rectangles. Two first side frames 11 and two second side frames 12 are provided around the bottom plate 13. The two first side frames 11 and the two second side frames 12 are connected end to end to form a rectangular frame. The first side frame 11 extends along the first direction X, and the second side frame 12 extends along the second direction Y. A protective cover is provided on the other side of the two first side frames 11 and the two second side frames 12 opposite to the bottom plate 13, such that the protective cover is disposed opposite to the bottom plate 13. The two first side frames 11 and the two second side frames 12 are connected between the protective cover and the bottom plate 13. The bottom plate 13, the protective cover, the two first side frames 11, and the two second side frames 12 surround to form a receiving cavity of the battery box 1.

[0032] The bottom plate 13 is used to support the battery pack 20. Therefore, the bottom plate 13 is a box wall 1a. Of course, in some other exemplary embodiments of the present disclosure, the cover plate 21 may also be the box wall 1a for supporting the battery pack 20.

[0033] In addition, in other exemplary embodiments of the present disclosure, the bottom plate 13 and the protective cover may be configured as circular, oval, trapezoidal, etc. The side frames may be provided as one or more and surround to form a circular, oval, trapezoidal, etc., such that the battery box 1 is formed into a cylindrical shape, an elliptical cylindrical shape, a prismatic shape, etc. The battery box 1 may also have other shapes, which will not be elaborated herein one by one.

[0034] A battery pack 20 is disposed in the battery box 1. The battery pack 20 may include at least two single cells 2. For example, the battery pack 20 may include two single cells 2, or the battery pack 20 may also include three or more single cells 2. At least two single cells 2 are arranged in a row along the first direction X to form a row of battery cells 201. For example, two single cells 2 may be arranged in a row along the first direction X to form a row of battery cells 201, or three or more single cells 2 may be arranged in a row along the first direction X to form a row of battery cells 201. Multiple batteries are arranged to form multiple rows of battery cells 201. Two adjacent rows of battery cells 201 form a set of battery packs 20. One set of battery packs 20 may be disposed in the battery box 1, or two or more sets of battery packs 20 may be disposed.

[0035] The single cells 2 in two adjacent rows of battery cells 201 are arranged in a staggered manner. For example, the gap between the single cell 2 in the first row and two adjacent single cells 2 in the second row is disposed opposite, rather than the single cell 2 in the first row being disposed directly opposite to the single cell 2 in the second row, so as to improve the space utilization rate of the receiving cavity of the battery box 1, thereby improving the energy density of the battery pack.

[0036] In this example implementation, refer to Figure 3 As shown, the single battery 2 can be a cylindrical battery, and the battery housing can be set as a cylinder, that is, the battery housing can include a cover plate 21 and a bottom wall 22 arranged opposite to each other, and the cover plate 21 and the bottom wall 22 are both set as a circle, and a side wall is connected between the cover plate 21 and the bottom wall 22, and the side wall is set as a cylinder. The side wall, the cover plate 21 and the bottom wall 22 surround and form a receiving cavity for the single battery 2. Of course, the single battery 2 can also be a quadrangular prism battery, a pentagonal prism battery, a hexagonal prism battery, etc.

[0037] The battery housing may be made of aluminum, steel or other metals and alloys. Of course, it may also be made of other materials, which are not described here one by one.

[0038] In this example embodiment, a battery cell is arranged in the accommodating cavity of the battery shell, and the battery cell may include a battery cell body, a first pole ear and a second pole ear, and the polarity of the first pole ear is opposite to that of the second pole ear. The battery cell body is arranged as a column, for example, the battery cell body can be arranged as a cylinder adapted to the battery shell. The battery cell body has a first end face and a second end face, and the first end face is arranged opposite to the second end face. The battery cell body may include a first pole piece and a second pole piece, and a separation film arranged between the first pole piece and the second pole piece, and the battery cell body may be formed by winding the first pole piece, the separation film and the second pole piece arranged in a stacked manner. Active material is coated on the first pole piece and the second pole piece.

[0039] The first pole ear is connected to the battery body, specifically, the first pole ear is connected to the first pole piece; the first pole ear is located at the first end surface of the battery body close to the cover plate 21. The second pole ear is connected to the battery body, specifically, the second pole ear is connected to the second pole piece; and the second pole ear can be located on the same side of the battery body as the first pole ear, that is, the second pole ear can be located at the first end surface of the battery body close to the cover plate 21, so that the first pole ear and the second pole ear are arranged on the side of the first end surface away from the battery body.

[0040] The first pole tab may be a portion of the multi-layer first pole sheet extending out of the battery body, and being bent to the side of the first end face of the battery body away from the battery body to form the first pole tab, so that the first pole tab may include a multi-layer first pole tab sheet. The second pole tab may be a portion of the multi-layer second pole sheet extending out of the battery body, and being bent to the side of the first end face of the battery body away from the battery body to form the second pole tab, so that the second pole tab may include a multi-layer second pole tab sheet.

[0041] It should be noted that the first pole tab and the second pole tab are conductive foil areas without active material coating, that is, no active material coating is coated on the first pole tab and the second pole tab, and the first pole tab and the second pole tab are current collecting layers for transmitting current.

[0042] In this example implementation, refer to Figure 3As shown, the battery terminal post 23 is insulated and connected to the cover plate 21. Specifically, a through hole is provided in the cover plate 21, the battery terminal post 23 passes through the through hole and is riveted to the cover plate 21. An insulating member is provided between the battery terminal post 23 and the cover plate 21 to insulate the battery terminal post 23 from the cover plate 21.

[0043] In the present exemplary embodiment, referring to Figure 4 As shown, a pressure relief valve 221 is provided on the bottom wall 22. The pressure relief valve 221 can be a weak structure provided on the bottom wall 22. After the battery cell undergoes thermal runaway, high-temperature gas, sparks, and high-temperature solid particles can break through the pressure relief valve 221 on the bottom wall 22 and spray out from the pressure relief valve 221 to prevent the single battery 2 from exploding.

[0044] Specifically, the pressure relief valve 221 can be a scratch or a groove provided on the bottom wall 22. The pressure relief valve 221 with a scratch or groove structure can be provided on the inner side of the bottom wall 22 close to the battery cell or on the outer side of the bottom wall 22 facing away from the battery cell. The scratch can be formed by mechanical processing, and the groove can be formed by photolithography or chemical etching. It can also be a weak structure where the thickness of the entire pressure relief valve 221 is thinner than that of other positions. In the present exemplary embodiment, the pressure relief valve 221 is a circular indentation provided on the first surface.

[0045] Referring to Figure 3 and Figure 4 As shown, the single battery 2 has electrode lead-out ends 2a and a pressure relief end 2b arranged opposite to each other. In the present exemplary embodiment, the battery terminal post 23 is the first electrode of the single battery 2, and the cover plate 21 is the second electrode of the single battery 2. For example, the battery terminal post 23 is the positive electrode of the single battery 2, and the cover plate 21 is the negative electrode of the single battery 2. Therefore, the end of the single battery 2 provided with the cover plate 21 and the battery terminal post 23 is the electrode lead-out end 2a of the single battery 2. A pressure relief valve 221 is provided on the bottom wall 22. Therefore, the end of the single battery 2 provided with the bottom wall 22 is the pressure relief end 2b of the single battery 2. The bottom wall 22 and the cover plate 21 are arranged opposite to each other, so that the electrode lead-out end 2a and the pressure relief end 2b are arranged opposite to each other.

[0046] Referring to Figures 1 - 3 As shown, a pressure relief space 3 is provided between the single battery 2 and the box wall 1a. The pressure relief space 3 is used to lead out the overheated gas sprayed out from the pressure relief valve 221 when the single battery 2 overheats. Therefore, the pressure relief valve 221 communicates with the pressure relief space 3. A pressure relief space 3 is provided between the bottom wall 22 of the single battery 2 and the bottom plate 13 of the battery box 1.

[0047] In the present exemplary embodiment, referring to Figure 2As shown, the heat exchange component 4 may include a first heat exchange plate 41 and heat exchange fins 42. The first heat exchange plate 41 is disposed between two adjacent single cells 2 and is in heat exchange contact with the two adjacent single cells 2. In the present exemplary embodiment, two adjacent battery columns 201 form a battery pack 20. A first heat exchange plate 41 is provided between two adjacent battery columns 201 belonging to the same battery pack 20. Heat exchange is performed on two adjacent battery columns 201 belonging to the same battery pack 20 through one first heat exchange plate 41, increasing the utilization rate of the internal space of the battery box 1. No first heat exchange plate 41 is provided between two adjacent battery columns 201 belonging to different battery packs.

[0048] The heat exchange fins 42 are connected to one end of the first heat exchange plate 41 close to the pressure relief space 3. The heat exchange fins 42 are located in the pressure relief space 3 and extend along the first direction X to divide the pressure relief space 3 into two sub-pressure relief spaces 31 extending along the first direction X. One sub-pressure relief space 31 is disposed opposite to at least one single cell 2. For example, one sub-pressure relief space 31 may be disposed opposite to one single cell 2, and one sub-pressure relief space 31 may be disposed opposite to two or more single cells 2 of one battery column 201. The extension length of the heat exchange fins 42 may be substantially the same as the extension length of the first heat exchange plate 41. By the heat exchange fins 42, the exhaust spaces of two adjacent single cells 2 can be isolated. In the case where one single cell 2 overheats and ejects overheated gas, the adjacent single cell 2 is not affected; moreover, the heat exchange fins 42 can cool the ejected overheated gas, further reducing the influence of the overheated gas on the adjacent single cell 2 and enhancing the safety performance of the battery pack.

[0049] In the present exemplary embodiment, a plurality of heat exchange fins 42 may be provided; for example, referring to Figure 3 and Figure 4 as shown, the number of the heat exchange fins 42 may be set to an odd number. Specifically, the heat exchange fins 42 may be set to three, five or more; referring to Figure 2 as shown, the number of the heat exchange fins 42 may be set to an even number. Specifically, the heat exchange fins 42 may be set to two, four or more. By a plurality of heat exchange fins 42, the overheated gas ejected when the single cell 2 overheats can be better cooled, further reducing the influence of the overheated gas on the adjacent single cell 2 and further enhancing the safety performance of the battery pack.

[0050] Moreover, a plurality of heat exchange fins 42 are sequentially spaced apart along the second direction Y, so that there is a gap between two adjacent heat exchange fins 42, that is, an air flow channel is formed between two adjacent heat exchange fins 42, and the overheated gas can flow in the air flow channel and be discharged out of the battery pack.

[0051] The second direction Y is perpendicular to the first direction X and parallel to the box wall 1a; that is, the arrangement direction of the plurality of heat exchange fins 42 is perpendicular to the extension direction of the heat exchange fins 42.

[0052] The heat exchange fins 42 located in the middle are the main fins 42a. Among the plurality of heat exchange fins 42, except for the main fins 42a, the remaining heat exchange fins 42 are auxiliary fins 42b. Refer to Figure 3 and Figure 4 As shown, when the number of heat exchange fins 42 is odd, it can be that one heat exchange fin 42 located in the middle is the main fin 42a; refer to Figure 2 As shown, when the number of heat exchange fins 42 is even, it can be that two heat exchange fins 42 located in the middle are the main fins 42a.

[0053] Of course, in some other exemplary embodiments of the present disclosure, when the number of heat exchange fins 42 is odd, it can also be that three heat exchange fins 42 located in the middle are the main fins 42a, or it can be that two heat exchange fins 42 located in the middle are the main fins 42a; when the number of heat exchange fins 42 is even, it can be that four heat exchange fins 42 located in the middle are the main fins 42a, or it can be that three heat exchange fins 42 located in the middle are the main fins 42a.

[0054] Therefore, the above-mentioned middle part is not only the middlemost position, but also a larger position range including the middlemost position. The number of heat exchange fins 42 on both sides of the main fin 42a can be the same or different.

[0055] In the height direction Z, the height of the main fin 42a is greater than the height of other heat exchange fins 42, that is, the height of the main fin 42a is greater than the height of the auxiliary fin 42b, that is, the height of the main fin 42a is the highest; the height of the main fin 42a is greater than or equal to the height of the pressure relief space 3. Through the main fin 42a, the pressure relief space 3 can be completely separated into two sub-pressure relief spaces 31, and there is basically no communication between the two sub-pressure relief spaces 31, further avoiding the influence on the adjacent single battery 2 in the case of overheating of one single battery 2 and ejecting overheated gas.

[0056] The height direction Z is perpendicular to the box wall 1a, that is, the height direction Z is perpendicular to the plane formed by the first direction X and the second direction Y.

[0057] Optionally, refer to Figures 2 - 4As shown, the height of multiple secondary fins 42b in the height direction Z increases as the distance between the secondary fin 42b and the primary fin 42a in the second direction Y decreases, that is, the closer the secondary fin 42b is to the primary fin 42a, the higher its height. This setting enables the overheated gas to flow through the multiple secondary fins 42b to the primary fin 42a in sequence. Both the primary fin 42a and the secondary fins 42b can cool the overheated gas, thereby increasing the cooling rate. Moreover, compared with the structure where the heights of the multiple secondary fins 42b are the same, due to the shielding effect of the higher secondary fins 42b, the overheated gas can more easily enter the air flow channels between two adjacent secondary fins 42b, enabling the multiple secondary fins 42b to come into more sufficient contact with the overheated gas, further increasing the cooling rate, and effectively using the air flow channels to discharge the overheated gas outside the battery pack to ensure the discharge rate of the overheated gas and avoid affecting other batteries.

[0058] Referring to Figure 2 As shown, that is, among two adjacent secondary fins 42b, the one closer to the primary fin 42a is the first secondary fin 42b1, and the one farther from the primary fin 42a is the second secondary fin 42b2. In the height direction Z, the height H11 of the first secondary fin 42b1 is greater than the height H12 of the second secondary fin 42b2.

[0059] In the present exemplary embodiment, referring to Figure 2 As shown, the heights of the secondary fins 42b are not consistent. Only the height of one secondary fin 42b is marked in Figure 2 . In the height direction Z, the ratio of the height H1 of the secondary fin 42b to the height H2 of the pressure relief space 3 is greater than or equal to 0.05 and less than or equal to 0.95. For example, the ratio of the height H1 of the secondary fin 42b to the height H2 of the pressure relief space 3 can be 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, etc.

[0060] If the ratio of the height H1 of the secondary fin 42b to the height H2 of the pressure relief space 3 is too large, resulting in too high a height of the secondary fin 42b and too small a width of the gap between the secondary fin 42b and the bottom plate 13, it is difficult for the overheated gas to flow through the gap between the secondary fin 42b and the bottom plate 13 to the primary fin 42a, making it difficult for the primary fin 42a to cool the overheated gas, thus reducing the cooling rate.

[0061] If the ratio of the height H1 of the secondary fin 42b to the height H2 of the pressure relief space 3 is too small, resulting in too small a height of the secondary fin 42b and too small an area of the secondary fin 42b, the cooling effect of the secondary fin 42b on the overheated gas is weak, also reducing the cooling rate.

[0062] The above numerical range not only enables the overheated gas to smoothly flow through the gap between the auxiliary fin 42b and the bottom plate 13 to the main fin 42a, and the main fin 42a can play a role in cooling the overheated gas, thereby ensuring the cooling rate; but also makes the area of the auxiliary fin 42b relatively large to ensure the cooling effect of the auxiliary fin 42b on the overheated gas, and also ensures the cooling rate.

[0063] In the present exemplary embodiment, the height H1 of the auxiliary fin 42b is greater than or equal to 0.5 mm and less than or equal to 19 mm. For example, the height H1 of the auxiliary fin 42b can be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm, 14 mm, 14.5 mm, 15 mm, 15.5 mm, 16 mm, 16.5 mm, 17 mm, 17.5 mm, 18 mm, 18.5 mm, etc.

[0064] The height H2 of the pressure relief space 3 is greater than or equal to 5 mm and less than or equal to 20 mm. For example, the height H2 of the pressure relief space 3 can be 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm, 14 mm, 14.5 mm, 15 mm, 15.5 mm, 16 mm, 16.5 mm, 17 mm, 17.5 mm, 18 mm, 18.5 mm, 19 mm, 19.5 mm, etc.

[0065] Optionally, a groove 1a1 is provided on the box wall 1a, and the end of the main fin 42a extends into the groove 1a1. In the present exemplary embodiment, refer to Figure 2As shown, the groove 1a1 is provided on the bottom plate 13. The cross-sectional shape of the groove 1a1 can be triangular, rectangular, trapezoidal, etc. The end of the main fin 42a extends into the groove 1a1, and the cross-sectional shape of the end of the main fin 42a is adapted to the cross-sectional shape of the groove 1a1. For example, when the cross-sectional shape of the groove 1a1 is triangular, the cross-sectional shape of the end of the main fin 42a is also triangular; when the cross-sectional shape of the groove 1a1 is rectangular, the cross-sectional shape of the end of the main fin 42a is also rectangular; when the cross-sectional shape of the groove 1a1 is trapezoidal, the cross-sectional shape of the end of the main fin 42a is also trapezoidal. The groove 1a1 can not only position the main fin 42a, but also increase the sealing performance of each sub-pressure relief space 31. Specifically, in the case where the groove 1a1 is not provided, only the end face of the main fin 42a abuts against the bottom plate 13, which is a single-face contact; in the case where the groove 1a1 is provided, at least two faces of the end of the main fin 42a abut against the groove wall of the groove 1a1, increasing the contact faces, and the contact faces are connected to form a curved surface, thereby increasing the sealing performance of each sub-pressure relief space 31, and further avoiding the influence on the adjacent single battery 2 in the case where one single battery 2 overheats and ejects overheated gas.

[0066] In some exemplary embodiments of the present disclosure, with reference to Figure 1 , Figure 3 and Figure 4 shown, the heat exchange assembly 4 may further include a second heat exchange plate 43. The second heat exchange plate 43 is connected between the first heat exchange plate 41 and the heat exchange fins 42, that is, the second heat exchange plate 43 is connected to one end of the first heat exchange plate 41 close to the pressure relief space 3, and the heat exchange fins 42 are connected to the side of the second heat exchange plate 43 facing away from the first heat exchange plate 41. It can also be said that the first heat exchange plate 41, the second heat exchange plate 43 and the heat exchange fins 42 are sequentially connected in the height direction Z.

[0067] The second heat exchange plate 43 is located in the pressure relief space 3, and both the second heat exchange plate 43 and the heat exchange fins 42 are located in the pressure relief space 3.

[0068] Since the first heat exchange plate 41 is provided between two adjacent single batteries 2, therefore, the orthographic projection of the first heat exchange plate 41 on the box wall 1a does not overlap with the orthographic projection of the single battery 2 on the box wall 1a. It can be that only a part of the edge line of the orthographic projection of the first heat exchange plate 41 on the box wall 1a coincides with a part of the edge line of the orthographic projection of the single battery 2 on the box wall 1a. The thickness of the first heat exchange plate 41 is the width of the space between two adjacent single batteries 2. In order to ensure the energy density of the battery pack, the width of the space between two adjacent single batteries 2 is set to be small, so that the thickness of the first heat exchange plate 41 in the second direction Y is also small, and a large number of heat exchange fins 42 cannot be provided at the end of the first heat exchange plate 41 close to the pressure relief space 3.

[0069] The orthographic projection of the second heat exchange plate 43 on the box wall 1a overlaps with the orthographic projection of the single battery 2 on the box wall 1a, so that the second heat exchange plate 43 can extend to cover the bottom surface of the single battery 2, that is, the width of the second heat exchange plate 43 in the second direction Y can be set wider, so that more heat exchange fins 42 can be set to increase the heat exchange efficiency and enhance the safety performance of the battery pack.

[0070] The orthographic projection of the second heat exchange plate 43 on the box wall 1a does not overlap with the orthographic projection of the pressure relief valve 221 on the box wall 1a, that is, the second heat exchange plate 43 does not cover the pressure relief valve 221. In the event of overheating of the single battery 2, it will not affect the explosion of the pressure relief valve 221, and the superheated gas ejected through the pressure relief valve 221 will not cause damage to the second heat exchange plate 43.

[0071] Reference Figures 1 - 3 As shown, the battery pack may further include a support structure 5, and the support structure 5 is arranged between the box wall 1a and the pressure relief end 2b. Figure 2 As shown, the support structure 5 may include two support plates 51 , a pressure relief space 3 is formed between the two support plates 51 , and the support structure 5 and the heat exchange fins 42 support a group of battery packs 20 .

[0072] Specifically, refer to Figure 1 and Figure 3 As shown, the support structure 5 may include a connecting plate 52 and two supporting plates 51. The connecting plate 52 is connected between the two supporting plates 51 and is located on the side of the supporting plate 51 away from the single battery 2, so that the support structure 5 is arranged in a horizontal "[" shape. One of the supporting plates 51 abuts against one column of battery columns 201, and the other supporting plate 51 abuts against another column of battery columns 201. There is a pressure relief space 3 between the two supporting plates 51. The support structure 5 and the heat exchange fins 42 jointly support a group of battery groups 20 to ensure the stability of the support for the battery groups 20.

[0073] In this case, the groove 1 a 1 may be provided on the connecting plate 52 .

[0074] Alternatively, refer to Figure 1 As shown, a support plate 51 can support two adjacent columns of single cells 2. Since the single cells 2 are cylindrical batteries, there are embedded parts between the two adjacent columns of single cells 2, that is, the single cells 2 in the first column are embedded between the two adjacent single cells 2 in the second column. Therefore, two adjacent columns of single cells 2 can be supported by a support plate 51, so that a group of battery packs 20 located between two groups of battery packs 20 can be provided with no support structure 5, thereby reducing the number of support structures 5, reducing the weight of the battery pack, and improving the energy density of the battery pack. The support plate 51 can be set to a wavy shape connected by multiple arc plates, and an arc plate of the support plate 51 is matched with a single cell 2, and the arc plate is concave to the side away from the central axis of the single cell 2.

[0075] In the present exemplary embodiment, with reference to Figure 3 as shown, the first heat exchange plate 41 may include a first sub - heat exchange plate 411 and a second sub - heat exchange plate 412. One first sub - heat exchange plate 411 is in thermal contact with the side wall of a cylindrical battery, and the first sub - heat exchange plate 411 is arranged in an arc shape adapted to the cylindrical battery; one second sub - heat exchange plate 412 is in thermal contact with the side wall of a cylindrical battery, and the second sub - heat exchange plate 412 is arranged in an arc shape adapted to the cylindrical battery. Such an arrangement can increase the thermal contact area between the first sub - heat exchange plate 411 and the second sub - heat exchange plate 412 and the single - cell battery 2, thereby improving the heat conduction efficiency of the first heat exchange plate 41.

[0076] The first sub - heat exchange plate 411 and the second sub - heat exchange plate 412 are recessed in opposite directions, and moreover, the first sub - heat exchange plate 411 and the second sub - heat exchange plate 412 are alternately and smoothly connected so that the first heat exchange plate 41 is arranged in a wavy shape. The first sub - heat exchange plate 411 and the second sub - heat exchange plate 412 can be tangentially connected, that is, the first sub - heat exchange plate 411 and the second sub - heat exchange plate 412 can be smoothly connected.

[0077] With reference to Figure 4 as shown, the heat exchange fins 42 are arranged in a wavy shape adapted to the first heat exchange plate 41. Specifically, the heat exchange fins 42 may include a first part 421 and a second part 422. The first part 421 is connected to the first sub - heat exchange plate 411, and the first part 421 is arranged in an arc shape adapted to the first sub - heat exchange plate 411; the second part 422 is connected to the second sub - heat exchange plate 412, and the second part 422 is arranged in an arc shape adapted to the second sub - heat exchange plate 412. Such an arrangement can increase the heat exchange area of the first part 421 and the second part 422, thereby improving the heat conduction efficiency of the heat exchange fins 42.

[0078] The first part 421 and the second part 422 are recessed in opposite directions, and moreover, the first part 421 and the second part 422 are alternately and smoothly connected so that the heat exchange fins 42 are arranged in a wavy shape. The first part 421 and the second part 422 can be tangentially connected, that is, the first part 421 and the second part can be smoothly connected.

[0079] Optionally, a heat exchange flow channel may be provided in the heat exchange fins 42, and a heat exchange medium may flow in the heat exchange flow channel. Through the heat exchange medium, the heat exchange efficiency of the heat exchange fins 42 can be further increased, and the safety performance of the battery pack can be enhanced.

[0080] In the present exemplary embodiment, the battery pack may further include a thermally conductive structural adhesive layer 6, which is bonded between the single cell 2 and the heat exchange component 4, that is, the single cell 2 and the heat exchange component 4 are bonded together through the thermally conductive structural adhesive. This makes the single cell 2 and the heat exchange component 4 in close contact, ensuring the heat transfer effect between the single cell 2 and the heat exchange component 4; moreover, it ensures the connection strength between the single cell 2 and the heat exchange component 4, thereby enhancing the overall strength of the battery pack.

[0081] In this application, the terms "parallel" and "perpendicular" do not only mean completely parallel and perpendicular, but may also have a certain error; for example, if the angle between the two is greater than or equal to 0° and less than or equal to 5°, it is considered that the two are parallel to each other; if the angle between the two is greater than or equal to 85° and less than or equal to 95°, it is considered that the two are perpendicular to each other.

[0082] Those skilled in the art will readily conceive of other embodiments of the present disclosure after considering the specification and practicing the utility model disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include known common knowledge or conventional technical means in the technical field not disclosed by the present disclosure. The specification and the embodiments are only regarded as exemplary, and the true scope and spirit of the present disclosure are pointed out by the appended claims.

Claims

1. A battery pack, characterized in that: include: A battery box, including a box wall; A battery pack is arranged in the battery box, the battery pack includes at least two single cells, and a pressure relief space is arranged between the single cells and the box wall; The heat exchange assembly includes a first heat exchange plate and a heat exchange fin, wherein the first heat exchange plate is arranged between two adjacent single cells and is in heat exchange contact with the two adjacent single cells, the heat exchange fin is connected to one end of the first heat exchange plate close to the pressure relief space, the heat exchange fin is located in the pressure relief space, and at least part of the heat exchange fin extends to the box wall, the heat exchange fin extends along a first direction to separate the pressure relief space into two sub-pressure relief spaces, and one of the sub-pressure relief spaces is arranged opposite to at least one single cell.

2. The battery pack according to claim 1, characterized in that: The heat exchange fins are arranged in plurality, and the plurality of heat exchange fins are arranged in sequence and spaced apart along the second direction. The heat exchange fins located in the middle are main fins, and the remaining heat exchange fins are auxiliary fins. In the height direction, the height of the main fins is greater than the height of the auxiliary fins, and the height of the main fins is greater than or equal to the height of the pressure relief space. The second direction is perpendicular to the first direction and parallel to the box wall, and the height direction is perpendicular to the box wall.

3. The battery pack according to claim 2, characterized in that: The heights of the plurality of auxiliary fins in the height direction increase as the distance between the auxiliary fins and the main fins in the second direction decreases.

4. The battery pack according to claim 2, characterized in that: In the height direction, a ratio of the height of the auxiliary fin to the height of the pressure relief space is greater than or equal to 0.05 and less than or equal to 0.

95.

5. The battery pack according to claim 4, characterized in that: The height of the auxiliary fin is greater than or equal to 0.5 mm and less than or equal to 19 mm, and / or the height of the pressure relief space is greater than or equal to 5 mm and less than or equal to 20 mm.

6. The battery pack according to claim 2, characterized in that: The box wall is used to support the battery pack. A groove is provided on the box wall. The end of the main fin extends into the groove.

7. The battery pack according to any one of claims 1 to 6, characterized in that: The heat exchange component also includes: The second heat exchange plate is connected between the first heat exchange plate and the heat exchange fins. The second heat exchange plate is located in the pressure relief space. The orthographic projection of the second heat exchange plate on the box wall overlaps with the orthographic projection of the single battery on the box wall.

8. The battery pack according to any one of claims 1 to 6, characterized in that: The single cell has an electrode lead-out terminal and a pressure relief terminal arranged opposite to each other, and the battery pack further comprises: A support structure is provided between the box wall and the pressure relief end, the support structure comprises two support plates, a pressure relief space is provided between the two support plates, and the support structure and the heat exchange fins support a group of the battery packs.

9. The battery pack according to claim 8, characterized in that: One of the support plates supports two adjacent rows of single cells.

10. The battery pack according to any one of claims 1 to 6, characterized in that: The single cell is a cylindrical cell, the first heat exchange plate includes a first sub-heat exchange plate and a second sub-heat exchange plate, the first sub-heat exchange plate and the second sub-heat exchange plate are arranged to be in an arc shape adapted to the cylindrical cell, and the first sub-heat exchange plate and the second sub-heat exchange plate are recessed in opposite directions, the first sub-heat exchange plate and the second sub-heat exchange plate are alternately and smoothly connected so that the first heat exchange plate is arranged to be in a wavy shape, and the heat exchange fins are arranged to be in a wavy shape adapted to the first heat exchange plate.

11. The battery pack according to any one of claims 1 to 6, characterized in that: The heat exchange fins are provided with heat exchange channels for accommodating heat exchange medium.

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