Battery pack and electric device

Abstract

The application provides a battery pack and an electric device to improve the technical problem of uneven foaming of foaming glue. The battery pack comprises a box body and a battery module; the box body has an opening at one end and an accommodating cavity formed in the interior and communicating with the opening; the battery module is arranged in the accommodating cavity; the battery module comprises an electric core group and foaming glue, the electric core group is spaced from the inner wall of the accommodating cavity, and the foaming glue is filled in the interior of the electric core group and between the electric core group and the inner wall of the accommodating cavity; the electric core group comprises a plurality of electric core layers which are sequentially and spacedly distributed along a first direction, each electric core layer comprises a plurality of electric cores which are sequentially and spacedly distributed along a second direction, the electric cores extend along a third direction, the first direction, the second direction and the third direction intersect, and the first direction is a direction from the bottom wall of the accommodating cavity to the opening; the battery pack comprises at least one boss, the boss is protruded on the surface of the bottom wall of the accommodating cavity, the surface of the boss towards the electric core group is a profiled surface which is profiled, and the distance between the profiled surface of each boss and the electric core group is equal.

Description

Technical Field

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

[0002] Most battery modules use bolts or clips to secure the cells. These methods require additional bolt components or complex molding structures for the clips, increasing labor costs. When there is insufficient space in the housing to accommodate the battery modules, it is also necessary to consider laying the cells flat and stacking them, which makes the structure of the flat-stacked battery module even more complex.

[0003] Related technologies use expanding foam to fix the battery cells in the battery module, which can greatly simplify the structure of the battery module. However, since the battery cells in the flat-lying stacked battery module are stacked, this can easily lead to insufficient uniformity of the expanding foam. Utility Model Content

[0004] The embodiments of this application provide a battery pack and an electrical device that can improve the technical problem of insufficient foaming uniformity of the foaming adhesive in a flat-lying stacked battery module.

[0005] In a first aspect, embodiments of this application provide a battery pack, comprising:

[0006] A housing, wherein one end of the housing has an opening and an internal cavity communicating with the opening; and

[0007] A battery module is disposed within a receiving cavity. The battery module includes a cell assembly and a foaming compound. The cell assembly is spaced apart from the inner wall of the receiving cavity, and the foaming compound fills the interior of the cell assembly and the space between the cell assembly and the inner wall of the receiving cavity. The cell assembly includes a plurality of cell layers spaced apart sequentially along a first direction. Each cell layer includes a plurality of cells spaced apart sequentially along a second direction. The cells extend along a third direction, wherein the first direction, the second direction, and the third direction intersect each other. The first direction is the direction from the bottom wall of the receiving cavity to the opening. The battery pack also includes at least one boss protruding from the bottom wall surface of the receiving cavity. The surface of the boss facing the cell assembly is a contoured surface, and the distance between the contoured surface of each boss and the cell assembly is equal.

[0008] Since the battery pack includes a housing and battery modules, the battery modules are housed within the housing cavity. Each battery module comprises battery cells and expanding foam, which is obtained by foaming and curing expanding foam raw material within the housing cavity. By spacing the battery cells between the housing cavity and the inner wall of the housing cavity, and by spacing different cell layers within the battery cells, as well as different cells within each cell layer, abundant interconnected channels are formed. These channels serve as foaming paths for the expanding foam raw material, reducing foaming resistance and allowing the expanding foam to better fill the interior of the battery cells and between the battery cells and the inner wall of the housing cavity. This improves the fixing effect of the expanding foam on the battery cells within the battery cells and on the fixing effect between the battery cells and the inner wall of the housing cavity. In addition, by setting protrusions with contoured surfaces on the bottom wall surface of the receiving cavity, channels of equal or similar width can be constructed between different cells and protrusions. When the foaming material in the receiving cavity foams upward, it will pass through these channels. Since the width of the channels is equal or similar, the foaming resistance faced by the foaming material is also similar, which helps to improve the uniformity of the upward foaming of the foaming material.

[0009] In one embodiment, the distance between the contoured surface of each boss and the battery cell assembly is 1mm to 2mm.

[0010] By controlling the spacing between the boss and the battery cell assembly, the uniformity of the foam adhesive can be improved, while also offering cost advantages.

[0011] In one embodiment, the battery cell is a cylindrical battery cell, and the contoured surface is an arc surface.

[0012] When the battery cell is a cylindrical cell, the contoured surface is an arc surface that conforms to the shape of the cylindrical cell. The arc surface can guide the foaming material to foam upward to a certain extent, which helps to increase the density of the foam near the opening and improve the uniformity of the foam.

[0013] In one embodiment, the boss extends along the third direction, and in the third direction, the ratio of the length of the boss to the length of the battery cell is greater than or equal to 0.5.

[0014] By controlling the length of the boss, the overall uniformity of the expanding foam can be improved.

[0015] In one embodiment, the battery module further includes a pair of brackets spaced apart on the third side, the battery cell group is located between the pair of brackets, and both ends of each battery cell are respectively connected to the pair of brackets.

[0016] By setting a bracket inside the housing cavity, the battery cells in the battery cell assembly are supported and fixed by the bracket, which makes it easier to maintain the distance between the battery cell assembly and the inner wall of the housing cavity.

[0017] In one embodiment, the bracket includes a first plate that stands upright on the bottom wall of the receiving cavity and corresponds to the side wall of the receiving cavity. A limiting groove is formed on the first plate, and the end of the battery cell is inserted into the limiting groove and is limited and engaged by the limiting groove.

[0018] By configuring the bracket to include a first plate, and using the limiting groove on the first plate to insert and limit the connection with the end of the battery cell, the stability of the connection between the battery cell and the first plate is ensured while reducing the difficulty of connecting the battery cell and the first plate.

[0019] In one embodiment, the end of the battery cell has an explosion-proof valve and a pole post, and the bottom wall of the limiting groove is provided with a first clearance hole and a second clearance hole, the explosion-proof valve corresponding to the first clearance hole and the pole post corresponding to the second clearance hole.

[0020] Since the end of the battery cell is inserted into the limiting groove, when the explosion-proof valve and the terminal are located on the end of the battery cell, the bottom wall of the limiting groove is provided with a first clearance hole and a second clearance hole to avoid the explosion-proof valve and the terminal respectively. In this way, when the battery cell is in thermal runaway, the explosion-proof valve can discharge the thermal runaway products to the side of the first plate away from the battery cell assembly through the first clearance hole. The first plate can isolate the thermal runaway products from the battery cell assembly and reduce the risk of thermal runaway propagation. In addition, the second clearance hole can avoid the interference of the foam adhesive and realize the connection between the terminal and the external circuit.

[0021] In one embodiment, a first support rib and a second support rib are provided at intervals on the side wall of the receiving cavity, extending from the bottom wall of the receiving cavity to the opening. The first support rib and the second support rib both abut against the side surface of the first plate away from the battery cell assembly. The first support rib, the second support rib, and the first plate divide the receiving cavity into an independent first sub-cavity and a second sub-cavity. The battery cell assembly and the foam are located in the first sub-cavity. The first clearance hole and the second clearance hole are both in communication with the second sub-cavity.

[0022] Because the first support rib, the second support rib, and the first plate divide the receiving cavity into independent first and second sub-cavities, during the manufacturing of the battery module, the battery cell assembly is placed in the first sub-cavity, and the foaming adhesive material is added to the first sub-cavity. The foaming adhesive material foams and solidifies in the first sub-cavity to form foamed adhesive. Since the first and second sub-cavities are independent, the foaming adhesive material does not easily enter the second sub-cavity, thus forming an empty cavity. Both the first and second clearance holes are connected to the second sub-cavity, which facilitates the explosion-proof valve to spray thermal runaway products into the second sub-cavity. Moreover, the second sub-cavity allows for easy connection of the terminals to the external circuit.

[0023] In one embodiment, the battery pack further includes a busbar that extends at least partially into the second sub-cavity and is connected to the terminal post.

[0024] When the pole is connected to the busbar, the second sub-cavity can provide a accommodating space for the busbar.

[0025] In one embodiment, a limiting post is protruding on the side surface of the first plate away from the battery cell assembly, and a limiting hole is formed on the busbar, wherein the limiting post is inserted into the limiting hole and engages with the limiting hole for limiting.

[0026] By using the limiting post on the first plate to insert and limit the fitting with the limiting hole on the busbar, the busbar is positioned on the first plate, thereby improving the stability of the connection between the busbar and the pole.

[0027] In one embodiment, the bracket further includes a second plate disposed at one end of the first plate near the opening, and the second plate is disposed at an angle to the first plate and extends above the battery cell assembly; the battery pack further includes a battery management system module disposed on the second plate and electrically connected to the battery cell.

[0028] By configuring the bracket to include a second plate, which is set at an angle to the first plate, the second plate is used to support the battery management system module, which is located above the cell pack. This not only makes the battery pack structure more compact, but also facilitates the electrical connection between the battery management system module and the cells in the cell pack.

[0029] In one embodiment, the battery pack further includes a first fixing frame and a battery management system module. One end of the first fixing frame is inserted and fixed to the foam adhesive, and the other end of the first fixing frame is located above the battery cell assembly. The battery management system module is disposed on the other end of the first fixing frame and is electrically connected to the battery cell.

[0030] In the battery pack, the battery management system module can be supported by a separate first fixing frame, and the first fixing frame can be fixed with foam, thereby simplifying the structure of the battery pack.

[0031] In one embodiment, the battery pack further includes a second fixing frame and a busbar. One end of the second fixing frame is inserted and fixed to the foam adhesive, and the other end of the second fixing frame is located above the battery cell assembly. The busbar is disposed on the other end of the second fixing frame and connected to the battery cell.

[0032] In the battery pack, the busbar can be supported by a separate second mounting bracket and fixed with expanding foam, thereby simplifying the structure of the battery pack.

[0033] In one embodiment, in the second direction, the distance between the battery cell and the sidewall of the receiving cavity is greater than the distance between two adjacent battery cells.

[0034] The distance between the battery cell and the side wall of the housing should not be too small to prevent the battery cell from being squeezed and failing.

[0035] In one embodiment, the spacing between two adjacent cells in the first direction is 2.5 mm to 3.5 mm.

[0036] The above settings allow the battery pack to maximize the uniformity of foaming of the expanding foam while ensuring energy density.

[0037] In one embodiment, the battery pack further includes a cover that covers the housing to close the opening.

[0038] By setting a cover to close the opening, the battery module is located in a closed containment cavity, and the box and cover together protect the battery module.

[0039] In one embodiment, the battery pack is a low-voltage battery pack, and the output voltage of the low-voltage battery pack is less than or equal to 48V.

[0040] Secondly, embodiments of this application provide an electrical device including the battery pack described above. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of the three-dimensional structure of a battery pack provided in an embodiment of this application. Figure 1 ;

[0043] Figure 2 This is a top view schematic diagram of a battery pack provided in an embodiment of this application;

[0044] Figure 3 yes Figure 2 A sectional view along line AA.

[0045] Figure 4 yes Figure 2 Sectional view along line BB;

[0046] Figure 5This is a schematic diagram of the three-dimensional structure of a battery pack provided in an embodiment of this application. Figure 2 The cover is omitted in the picture;

[0047] Figure 6 This is a three-dimensional structural diagram of a battery pack housing provided in an embodiment of this application;

[0048] Figure 7 This is a schematic diagram of the three-dimensional structure of a battery pack provided in an embodiment of this application. Figure 3 The box and lid are omitted in the picture;

[0049] Figure 8 This is a schematic diagram of the three-dimensional structure of a battery pack provided in an embodiment of this application. Figure 4 The box and lid are omitted in the picture;

[0050] Figure 9 This is a schematic diagram of the three-dimensional structure of a battery pack provided in an embodiment of this application. Figure 5 The box body, lid, and expanding foam are omitted in the picture;

[0051] Figure 10 yes Figure 9 Enlarged view of section C;

[0052] Figure 11 This is a schematic diagram of the three-dimensional structure of a battery pack provided in an embodiment of this application. Figure 6 The box body, lid, and expanding foam are omitted in the picture;

[0053] Figure 12 This is a schematic diagram of a three-dimensional structure of a bracket in a battery pack, provided by an embodiment of this application. Figure 1 ;

[0054] Figure 13 This is a schematic diagram of a three-dimensional structure of a bracket in a battery pack, provided by an embodiment of this application. Figure 2 ;

[0055] Figure 14 This is a schematic diagram of the three-dimensional structure of another bracket in a battery pack provided in an embodiment of this application. Figure 1 ;

[0056] Figure 15 This is a schematic diagram of the three-dimensional structure of another bracket in a battery pack provided in an embodiment of this application. Figure 2 ;

[0057] Figure 16 This is a cross-sectional view of another battery pack provided in an embodiment of this application;

[0058] Figure 17 This is a schematic diagram of the structure of the electrical device provided in the embodiments of this application.

[0059] Explanation of reference numerals in the attached figures:

[0060] 100. Battery pack; 1. Housing; 11. Opening; 12. Receiving cavity; 121. First sub-cavity; 122. Second sub-cavity; 13. First support rib; 14. Second support rib; 2. Battery module; 21. Cell assembly; 211. Cell layer; 2111. Cell; 2112. Explosion-proof valve; 2113. Terminal post; 22. Foam; 23. Bracket; 231. First plate; 2311. Limiting groove; 2312. First clearance hole; 2313. Second clearance hole; 2314. Limiting post; 232. Second plate; 2321. Supporting post; 3. Boss; 31. Contour surface; 4. Busbar; 41. Limiting hole; 5. Battery management system module; 6. First fixing frame; 7. Second fixing frame; 8. Cover; 200. Electrical device. Detailed Implementation

[0061] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. 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.

[0062] Furthermore, it should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or operation, specifically the directions shown in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0063] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0064] 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, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0065] The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0066] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0067] To facilitate understanding of the present application, the spline curves and arrows used in the reference numerals in the accompanying drawings are explained below: spline curves without arrows indicate solid parts, that is, parts with solid structures; spline curves with arrows indicate virtual parts, that is, parts without solid structures.

[0068] Firstly, please see Figures 1 to 16 This application provides a battery pack 100. Specifically, the battery pack 100 includes a housing 1 and a battery module 2. One end of the housing 1 has an opening 11 and an internal receiving cavity 12 communicating with the opening 11. The battery module 2 is disposed within the receiving cavity 12; the battery module 2 includes a cell assembly 21 and a foam 22. The cell assembly 21 is spaced apart from the inner wall of the receiving cavity 12, and the foam 22 fills the interior of the cell assembly 21 and the space between the cell assembly 21 and the inner wall of the receiving cavity 12. The cell assembly 21 includes a plurality of cell layers 211 sequentially spaced along a first direction, and each cell layer 211 includes a plurality of cells 2111 sequentially spaced along a second direction. The cells 2111 extend along a third direction, wherein the first direction, the second direction, and the third direction intersect each other, and the first direction is the direction from the bottom wall of the receiving cavity 12 to the opening 11.

[0069] The battery pack 100 includes a housing 1 and a battery module 2. The battery module 2 is disposed inside the housing 1, thereby protecting the battery module 2 using the housing 1. The housing 1 has an opening 11 and a receiving cavity 12, and the battery module 2 is disposed inside the receiving cavity 12 through the opening 11.

[0070] It can be understood that the housing 1 forms the inner wall of the receiving cavity 12. The inner wall of the receiving cavity 12 includes a bottom wall and a side wall. The bottom wall of the receiving cavity 12 is opposite to the opening 11. The side wall of the receiving cavity 12 is arranged around the bottom wall of the receiving cavity 12, and the end of the side wall of the receiving cavity 12 away from the bottom wall of the receiving cavity 12 defines the opening 11.

[0071] The battery module 2 includes a cell assembly 21 and expanding foam 22. The battery module 2 is disposed within a receiving cavity 12, and both the cell assembly 21 and the expanding foam 22 are disposed within the receiving cavity 12. The cell assembly 21 is spaced apart from the inner wall of the receiving cavity 12, meaning there is a gap between the cell assembly 21 and the inner wall of the receiving cavity 12. The expanding foam 22 fills the interior of the cell assembly 21 and also fills the space between the cell assembly 21 and the inner wall of the receiving cavity 12. Thus, the expanding foam 22 not only fixes the cell assembly 21 but also secures it to the inner wall of the receiving cavity 12. Typically, the cell assembly 21 includes multiple cells 2111, and the expanding foam 22 fills the space between the cells 2111.

[0072] It should be noted that foam 22 is a solid, obtained by foaming and curing a foaming raw material. As an example, foam 22 is polyurethane foam. The foaming raw material of polyurethane foam includes polyurethane prepolymer, foaming agent, and catalyst. The foaming raw material can react with moisture in the air or moisture in the matrix to produce gases (such as carbon dioxide, nitrogen, etc.). These gases expand rapidly in the colloid, forming a large number of tiny bubbles. As the number and expansion of bubbles increase, the colloid gradually becomes fluffy and soft, eventually forming a foamed material, i.e., foam. In other examples, foam 22 can also be selected from at least one of acrylic foam, polyester foam, silicone foam, and amino silicone foam. When the type of foam 22 changes, the composition of the foaming raw material will also change accordingly.

[0073] In preparing the expanding foam 22, the expanding foam raw material is added into the receiving cavity 12. Under the action of gravity, the expanding foam raw material falls onto the bottom wall of the receiving cavity 12, and expands towards the opening 11 of the housing 1 during foaming. Since the battery cell assembly 21 is also located in the receiving cavity 12, not only will the resistance of the expanding foam raw material increase, but the expanding foam raw material will also form multiple foaming paths during foaming. When the resistance of different foaming paths is different, it will lead to insufficient uniformity of the final expanding foam 22. Poor uniformity of the expanding foam 22 will further affect the effect of the expanding foam 22 on fixing the battery cell assembly 21.

[0074] Therefore, this application embodiment improves the battery cell assembly 21 disposed in the receiving cavity 12.

[0075] In detail, the cell assembly 21 includes multiple cell layers 211, and each cell layer 211 includes multiple cells 2111. Here, "multiple" refers to two or more cells. For example, please refer to [link to example]. Figure 4 The battery pack 21 contains two battery cell layers 211, and each battery cell layer 211 includes two battery cells 2111. Of course, in other examples, the number of battery cell layers 211 in the battery pack 21 can also be 3, 4, 5, 7, 9 or 10, and the number of battery cells 2111 in each battery cell layer 211 can also be 3, 4, 6, 8 or 10, which is not limited here.

[0076] The battery cell 2111, also known as a battery unit, is the smallest unit that converts electrochemical energy into electrical energy. The battery cell 2111 can be selected from battery cells using different cathode material systems, including but not limited to lithium iron phosphate cells and lithium nickel cobalt manganese oxide cells. The shape of the battery cell 2111 can also be selected according to requirements. As an example, the battery cell 2111 is a cylindrical cell. Of course, in other examples, the battery cell 2111 can also be a square cell, a hexagonal prism cell, or an irregularly shaped cell.

[0077] In the cell assembly 21, different cell layers 211 are spaced apart from each other, meaning there are gaps between different cell layers 211. Specifically, all cell layers 211 in the cell assembly 21 are distributed sequentially at intervals along a first direction. For example, please refer to... Figure 4 The first direction is the Z-axis direction, and the two cell layers 211 are distributed at intervals along the Z-axis direction. The cell layer 211 located above is called the top cell layer, and the cell layer 211 located below is called the bottom cell layer.

[0078] Within each cell layer 211, different cells 2111 are also spaced apart from each other, meaning there are gaps between different cells 2111. Specifically, all cells 2111 in the cell layer 211 are sequentially spaced apart along a second direction. The second direction differs from the first direction; specifically, the second direction intersects the first direction. Optionally, the second direction is perpendicular to the first direction. For an example, please refer to [link to example]. Figure 4 The second direction is the X-axis direction, and the two cells 2111 are spaced apart along the X-axis direction.

[0079] Since different cell layers 211 are spaced apart from each other, and different cells 2111 in each cell layer 211 are also spaced apart from each other, that is, all cells 2111 in the cell group 21 are spaced apart from each other.

[0080] Furthermore, the battery cells 2111 in the cell layer 211 extend along a third direction, which is different from the first direction and also different from the second direction. Specifically, the third direction intersects the first direction and also intersects the second direction. Optionally, the third direction is perpendicular to the first direction and also perpendicular to the second direction. That is to say, in the cell layer 211, different battery cells 2111 are distributed side by side with intervals, rather than being arranged end to end. For an example, please refer to [link to example]. Figure 3 and Figure 11 The third direction is the Y-axis direction, and cell 2111 extends along the Y-axis direction.

[0081] Furthermore, the first direction is from the bottom wall of the receiving cavity 12 to the opening 11, which is also the depth direction of the receiving cavity 12. That is to say, all the battery cell layers 211 in the battery cell assembly 21 are distributed sequentially and at intervals along the direction from the bottom wall of the receiving cavity 12 to the opening 11, that is, the battery cell layers 211 in the battery cell assembly 21 are distributed in the receiving cavity 12 in a similar "stacked" manner, which can save space in the length or width direction of the housing 1.

[0082] In this embodiment, the battery pack 100 includes a housing 1 and a battery module 2, with the battery module 2 disposed within the receiving cavity 12 of the housing 1. The battery module 2 includes a cell assembly 21 and a foaming compound 22, which is obtained by foaming and curing the foaming compound raw material within the receiving cavity 12. By spacing the cell assembly 21 from the inner wall of the receiving cavity 12, and by spacing different cell layers 211 within the cell assembly 21 from each other, and different cells 2111 within each cell layer 211 from each other, a rich network of interconnected channels is formed. These interconnected channels can serve as foaming paths during the foaming of the foaming compound raw material. This reduces foaming resistance and allows the obtained foaming compound 22 to better fill the interior of the cell assembly 21 and between the cell assembly 21 and the inner wall of the receiving cavity 12, thereby improving the fixing effect of the foaming compound 22 on the cells 2111 within the cell assembly 21 and the fixing effect between the cell assembly 21 and the inner wall of the receiving cavity 12.

[0083] For some embodiments of this application, please refer to Figure 4 In two adjacent cell layers 211, the spacing between two adjacent cells 2111 in the cell layer 211 closer to the opening 11 is greater than the spacing between two adjacent cells 2111 in the cell layer 211 farther from the opening 11.

[0084] When the cell assembly 21 is disposed within the receiving cavity 12, in two adjacent cell layers 211, the spacing between two adjacent cells 2111 in the cell layer 211 closer to the opening 11 is greater than the spacing between two adjacent cells 2111 in the cell layer 211 farther from the opening 11. Since the different cells 2111 in the cell layer 211 are spaced apart, there is a spacing between two adjacent cells 2111; this spacing is called the cell spacing for easy distinction. In the cell assembly 21, the cell spacing varies in different cell layers 211. Specifically, the cell spacing is larger in the cell layer 211 closer to the opening 11. For an example, please refer to [link to example]. Figure 4 The cell spacing D1 of the top cell layer is greater than the cell spacing D2 of the bottom cell layer, i.e., D1 > D2.

[0085] Since the foaming material expands from the bottom wall of the cavity 12 towards the opening 11 during foaming, the direction of expansion of the foaming material is opposite to the direction of gravity. The closer to the opening 11, the less foaming material there is due to gravity. However, by setting the battery cell group 21 in the cavity 12 to be in two adjacent battery cell layers 211, the spacing between two adjacent battery cells 2111 in the battery cell layer 211 closer to the opening 11 is greater than the spacing between two adjacent battery cells 2111 in the battery cell layer 211 farther from the opening 11, the foaming resistance of the foaming material can be reduced in the direction closer to the opening 11. This can alleviate the problem of reduced foaming caused by gravity to a certain extent, thereby improving the uniformity of the obtained foaming material 22.

[0086] For some embodiments of this application, please refer to Figure 4 and Figure 6 The battery pack 100 also includes at least one boss 3, which protrudes from the bottom wall surface of the receiving cavity 12. The surface of the boss 3 facing the cell assembly 21 is a contoured surface 31, and the distance between the contoured surface 31 of each boss 3 and the cell assembly 21 is equal.

[0087] The number of bosses 3 can be one or more. When there are multiple bosses 3, the shapes of different bosses 3 can be the same or different. Different bosses 3 can be connected and disposed on the bottom wall surface of the receiving cavity 12, or they can be disposed at intervals on the bottom wall surface of the receiving cavity 12. The bosses 3 protrude from the bottom wall surface of the receiving cavity 12. They can be assembled on the bottom wall of the receiving cavity 12 as separate parts, or they can be integrally formed with the housing 1.

[0088] The surface of the boss 3 facing the cell assembly 21 is a contoured surface 31. This contoured surface 31 mimics the surface shape of the adjacent cell 2111. For example, when the surface shape of the adjacent cell 2111 is arc-shaped, the shape of the contoured surface 31 is also arc-shaped.

[0089] It should be noted that a boss 3 can have one or more contoured surfaces 31. Typically, a contoured surface 31 follows the surface shape of a neighboring cell 2111. However, a cell 2111 may be adjacent to one or more contoured surfaces 31.

[0090] Since the boss 3 is located on the bottom wall surface of the receiving cavity 12, the battery cell 2111 of the contour surface 31 adjacent to the boss 3 is the battery cell 211 of the battery cell layer 211 that is furthest from the opening 11 in the battery cell group 21.

[0091] The distance between each protrusion 3 and the cell assembly 21 is specifically the distance between the contoured surface 31 of the protrusion 3 and the surface of the adjacent cell 2111. Since the distance between the contoured surface 31 of each protrusion 3 and the cell assembly 21 is equal, each contoured surface 31 is equally spaced from the surface of its adjacent cell 2111. Therefore, channels of equal or similar width can be constructed between different cells 2111 and protrusions 3.

[0092] As can be seen, the above arrangement can construct channels of equal or similar width between different cells 2111 and protrusions 3. When the foaming material in the receiving cavity 12 foams upward (i.e. foams towards the opening 11), it will pass through these channels. Since the width of the channels is equal or similar, the foaming resistance faced by the foaming material is also similar, which helps to improve the uniformity of the upward foaming of the foaming material.

[0093] For some embodiments of this application, please refer to Figure 4 and Figure 6 Cell 2111 is a cylindrical cell, and the contoured surface 31 is an arc surface.

[0094] Cylindrical cells have a smaller volume expansion rate during cycling, which reduces the compression and damage to the foam 22 by the cell 2111 in the later stages of cycling.

[0095] When the cell 2111 is a cylindrical cell, the contour surface 31 is an arc surface that conforms to the shape of the cylindrical cell. The arc surface can guide the foaming material to foam upward to a certain extent, which helps to increase the density of the part of the foam 22 near the opening 11 and improve the uniformity of the foam 22.

[0096] In one embodiment, please refer to Figure 6The boss 3 extends along the third direction, and in the third direction, the ratio of the length of the boss 3 to the length of the cell 2111 is greater than or equal to 0.5.

[0097] The boss 3 extends in the same direction (third direction) as the battery cell 2111. In the third direction, the length of the boss 3 shall not be less than half the length of the battery cell 2111.

[0098] As an example, in the third direction, the ratio of the length of the boss 3 to the length of the cell 2111 is 0.5, 0.6, 0.7, 0.8, 0.9, 1.0 or 1.2.

[0099] If the length of the boss 3 is too short, it can only improve the local uniformity of the expanding foam 22. By controlling the length of the boss 3, the overall uniformity of the expanding foam 22 can be improved.

[0100] For some embodiments of this application, please refer to Figure 4 The distance between the contoured surface 31 of each protrusion 3 and the battery cell assembly 21 is 1mm to 2mm.

[0101] The distance between the boss 3 and the cell assembly 21 is specifically the distance between the contoured surface 31 of the boss 3 and the surface of the adjacent cell 2111, that is, the width of the channel constructed between the cell 2111 and the boss 3. If the width of the channel is too small, it will increase the foaming resistance of the foaming material, while if the width of the channel is too large, it will cause some redundancy of the foaming material 22, wasting material.

[0102] As an example, the distance between the boss 3 and the battery cell group 21 is any one or any two of the following: 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm and 2.0mm.

[0103] By controlling the distance between the boss 3 and the cell assembly 21, the uniformity of the foam 22 can be improved, while also having a cost advantage.

[0104] For some embodiments of this application, please refer to Figures 7 to 15 The battery module 2 also includes a pair of brackets 23 spaced apart in the third direction, the cell group 21 is located between the pair of brackets 23, and the two ends of each cell 2111 are respectively connected to the pair of brackets 23.

[0105] The battery module 2 also includes a pair of supports 23. Since the battery module 2 is disposed within the receiving cavity 12, the pair of supports 23 are also disposed within the receiving cavity 12. The pair of supports 23 refers to two supports 23, which, for ease of distinction, are referred to as the first support and the second support, respectively. The first support and the second support are distributed alternately along a third direction, and the cell assembly 21 is disposed between the first support and the second support. The cell 2111 in the cell assembly 21 also extends along a third direction, with one end of the cell 2111 connected to the first support and the other end connected to the second support. Thus, the first support and the second support provide support and fixation for the cell 2111 in the cell assembly 21.

[0106] By setting a bracket 23 inside the receiving cavity 12, the battery cells 2111 in the battery cell assembly 21 are supported and fixed by the bracket 23, which makes it easier to keep the battery cell assembly 21 and the inner wall of the receiving cavity 12 apart.

[0107] For some embodiments of this application, please refer to Figure 3 , Figures 12 to 15 The bracket 23 includes a first plate 231 erected on the bottom wall of the receiving cavity 12 and corresponding to the side wall of the receiving cavity 12. A limiting groove 2311 is formed on the first plate 231. The end of the battery cell 2111 is inserted into the limiting groove 2311 and is limited and engaged with the limiting groove 2311.

[0108] The support 23 includes a first plate 231, which stands upright on the bottom wall of the receiving cavity 12 and corresponds to the side wall of the receiving cavity 12. The first plate 231 can be stacked together with the side wall of the receiving cavity 12, or it can be positioned face-to-face with the side wall of the receiving cavity 12. A limiting groove 2311 is formed on the first plate 231. This limiting groove 2311 can be formed by a recess in one side surface of the first plate 231, or it can be formed by a protruding rib on one side surface of the first plate 231, which defines the limiting groove 2311. The limiting groove 2311 is used to insert and engage with the end of the battery cell 2111, and to limit and fix the end of the battery cell 2111.

[0109] As an example, cell 2111 is a cylindrical cell, and the limiting groove 2311 is a circular groove that fits one end of the cylindrical cell.

[0110] Optionally, the ratio of the depth of the limiting groove 2311 to the length of the battery cell 2111 is 0.1 to 0.2, for example, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 or 0.2.

[0111] Because the limiting groove 2311 and the end of the battery cell 2111 are inserted and limited together, the limiting groove 2311 and the battery cell 2111 are set one-to-one. The number of upper limiting grooves 2311 on the first plate 231 of a single bracket 23 is equal to the number of battery cells 2111 in the battery cell group 21. In order to ensure that different battery cells 2111 in the battery cell group 21 are spaced apart from each other, the different limiting grooves 2311 on the first plate 231 are also spaced apart from each other. That is to say, the position of the battery cells 2111 in the battery cell group 21 can be adjusted by adjusting the position of the upper limiting groove 2311 on the first plate 231.

[0112] By configuring the bracket 23 to include the first plate 231, and using the limiting groove 2311 on the first plate 231 to insert and limit the end of the battery cell 2111, the connection between the battery cell 2111 and the first plate 231 is stabilized while reducing the difficulty of connecting the battery cell 2111 and the first plate 231.

[0113] In other embodiments, the battery cell 2111 and the first plate 231 can also be connected in other ways, including but not limited to bonding, snap-fitting, etc.

[0114] For some embodiments of this application, please refer to Figures 7 to 11 The end of the battery cell 2111 has an explosion-proof valve 2112 and a pole post 2113. The bottom wall of the limiting groove 2311 is provided with a first clearance hole 2312 and a second clearance hole 2313. The explosion-proof valve 2112 corresponds to the first clearance hole 2312, and the pole post 2113 corresponds to the second clearance hole 2313.

[0115] The battery cell 2111 typically has an explosion-proof valve 2112 and a terminal 2113. The explosion-proof valve 2112 can release pressure in the event of thermal runaway of the battery cell 2111, while the terminal 2113 can enable the battery cell 2111 to be electrically connected to an external circuit (a circuit outside the battery cell 2111) to achieve the transmission of current or data.

[0116] The explosion-proof valve 2112 and the pole post 2113 are located at the end of the battery cell 2111. The explosion-proof valve 2112 and the pole post 2113 can be installed on one end of the battery cell 2111, or the explosion-proof valve 2112 and the pole post 2113 can be installed on both ends of the battery cell 2111.

[0117] The explosion-proof valve 2112 corresponds to the first clearance hole 2312. The explosion-proof valve 2112 can extend into the first clearance hole 2312, or it can simply be positioned similarly but not extend into the first clearance hole 2312. The pole 2113 corresponds to the second clearance hole 2313. The pole 2113 can extend into the second clearance hole 2313, or it can simply be positioned similarly but not extend into the second clearance hole 2313. The first clearance hole 2312 and the second clearance hole 2313 can be connected or independent of each other.

[0118] Since the end of the battery cell 2111 is inserted into the limiting groove 2311, when the explosion-proof valve 2112 and the pole post 2113 are located on the end of the battery cell 2111, the first clearance hole 2312 and the second clearance hole 2313 provided through the bottom wall of the limiting groove 2311 can respectively avoid the explosion-proof valve 2112 and the pole post 2113. In this way, when the battery cell 2111 experiences thermal runaway, the explosion-proof valve 2112 can discharge the thermal runaway products to the side of the first plate 231 away from the battery cell assembly 21 through the first clearance hole 2312. The first plate 231 can isolate the thermal runaway products from the battery cell assembly 21, reducing the risk of thermal runaway propagation. In addition, the second clearance hole 2313 can avoid the interference of the foam adhesive 22 and realize the connection between the pole post 2113 and the external circuit (e.g., the busbar 4).

[0119] For some embodiments of this application, please refer to Figure 2 , Figure 3 and Figure 6 The side wall of the receiving cavity 12 is provided with a first support rib 13 and a second support rib 14 extending from the bottom wall of the receiving cavity 12 to the opening 11. The first support rib 13 and the second support rib 14 abut against the side surface of the first plate 231 away from the battery cell assembly 21. The first support rib 13, the second support rib 14 and the first plate 231 divide the receiving cavity 12 into an independent first sub-cavity 121 and a second sub-cavity 122. The battery cell assembly 21 and the foam 22 are located in the first sub-cavity 121. The first clearance hole 2312 and the second clearance hole 2313 are both connected to the second sub-cavity 122.

[0120] Optionally, both the first support rib 13 and the second support rib 14 extend along the first direction from the bottom wall of the receiving cavity 12 to the opening 11.

[0121] Since the first support rib 13, the second support rib 14, and the first plate 231 divide the receiving cavity 12 into an independent first sub-cavity 121 and a second sub-cavity 122, when manufacturing the battery module 2, the cell assembly 21 is placed in the first sub-cavity 121, and the foaming adhesive material is added to the first sub-cavity 121. The foaming adhesive material foams and solidifies in the first sub-cavity 121 to form foaming adhesive 22. Since the first sub-cavity 121 and the second sub-cavity 122 are independent, the foaming adhesive material does not easily enter the second sub-cavity 122, thus the second sub-cavity 122 is formed as an empty cavity. The first clearance hole 2312 and the second clearance hole 2313 are both connected to the second sub-cavity 122, which facilitates the explosion-proof valve 2112 to spray thermal runaway products into the second sub-cavity 122. Moreover, the second sub-cavity 122 can be used to easily connect the terminal post 2113 to the external circuit.

[0122] For some embodiments of this application, please refer to Figure 3 , Figure 5 , Figures 7 to 11 The battery pack 100 also includes a busbar 4, which extends at least partially into the second sub-cavity 122 and is connected to the terminal post 2113.

[0123] The manifold 4 may be partially inserted into the second sub-cavity 122 and partially located outside the second sub-cavity 122; or the manifold 4 may be entirely housed within the second sub-cavity 122. As an example, the manifold 4 is an aluminum busbar.

[0124] The battery pack 100 contains multiple busbars 4. Some busbars 4 connect only to the terminals 2113 of different cells 2111, thus achieving electrical connection between different cells 2111. Other busbars 4 can connect the terminals 2113 of cells 2111 to the battery management system module 5 in the battery pack 100, thus achieving electrical connection between cells 2111 and the battery management system module 5.

[0125] When the pole post 2113 is connected to the manifold 4, the second sub-cavity 122 can provide a accommodating space for the manifold 4.

[0126] For some embodiments of this application, please refer to Figure 7 , Figure 12 and Figure 15 The first plate 231 has a limiting post 2314 protruding on the side surface opposite to the battery cell assembly 21. The busbar 4 has a limiting hole 41. The limiting post 2314 is inserted into the limiting hole 41 and is limited and engaged with the limiting hole 41.

[0127] The number of upper limit posts 2314 on the first plate 231 can be one or more. The number of upper limit holes 41 on the manifold 4 can be one or more. The upper limit posts 2314 and the upper limit holes 41 are set one-to-one, and the upper limit posts 2314 and the upper limit holes 41 are inserted and locked.

[0128] By using the limiting post 2314 on the first plate 231 to insert and limit the fitting with the limiting hole 41 on the busbar 4, the busbar 4 is positioned on the first plate 231, thereby improving the stability of the connection between the busbar 4 and the pole post 2113.

[0129] For some embodiments of this application, please refer to Figure 7 , Figures 12 to 15 The bracket 23 also includes a second plate 232, which is disposed at one end of the first plate 231 near the opening 11, and the second plate 232 is disposed at an angle to the first plate 231 and extends above the cell assembly 21; the battery pack 100 also includes a battery management system module 5, which is disposed on the second plate 232 and electrically connected to the cell 2111.

[0130] As an example, the second plate 232 is set at a 90-degree angle to the first plate 231, that is, the bracket 23 is L-shaped, and the second plate 232 and the first plate 231 are integrally formed.

[0131] The battery management system module 5 and the battery cell 2111 can be electrically connected via the busbar 4. After the battery management system module 5 is electrically connected to the battery cell 2111, it can manage and control the operation of the battery cell 2111. As an example, the battery management system module 5 includes a BMS board.

[0132] By configuring the bracket 23 to also include a second plate 232, which is set at an angle to the first plate 231, the second plate 232 is used to support the battery management system module 5, which is located above the cell group 21. This not only makes the structure of the battery pack 100 more compact, but also facilitates the electrical connection between the battery management system module 5 and the cell 2111 in the cell group 21.

[0133] For example, see Figures 12 to 15 The second plate 232 is provided with a support column 2321, and the battery management system module 5 is directly supported on the support column 2321.

[0134] For some embodiments of this application, please refer to Figure 16 The battery pack 100 also includes a first fixing frame 6 and a battery management system module 5. One end of the first fixing frame 6 is inserted and fixed to the foam 22, and the other end of the first fixing frame 6 is located above the cell group 21. The battery management system module 5 is disposed on the other end of the first fixing frame 6 and is electrically connected to the cell 2111.

[0135] In the battery pack 100, the battery management system module 5 can also be supported by an independent first fixing frame 6, and the first fixing frame 6 can be fixed by foam 22, thereby simplifying the structure of the battery pack 100.

[0136] As an example, the first fixing frame 6 is an L-shaped or T-shaped support piece. When preparing the expanding foam 22, one end of the first fixing frame 6 is inserted into the receiving cavity 12, and the depth of the first fixing frame 6 inserted into the receiving cavity 12 is controlled. Expanding foam material is added into the receiving cavity 12, so that the foam of the expanding foam material wraps around one end of the first fixing frame 6. After the foam solidifies, solid expanding foam 22 is obtained, and one end of the first fixing frame 6 is fixed by the expanding foam 22.

[0137] For some embodiments of this application, please refer to Figure 16The battery pack 100 also includes a second fixing frame 7 and a busbar 4. One end of the second fixing frame 7 is inserted and fixed to the foam 22, and the other end of the second fixing frame 7 is located above the cell group 21. The busbar 4 is disposed on the other end of the second fixing frame 7 and connected to the cell 2111.

[0138] In the battery pack 100, the busbar 4 can also be supported by an independent second fixing frame 7, and the busbar 4 can be fixed by foam 22, thereby simplifying the structure of the battery pack 100.

[0139] As an example, the second fixing frame 7 is an L-shaped or T-shaped support piece. When preparing the expanding foam 22, one end of the second fixing frame 7 is inserted into the receiving cavity 12, and the depth of the second fixing frame 7 inserted into the receiving cavity 12 is controlled. Expanding foam material is added into the receiving cavity 12, so that the foam formed by the expanding foam material wraps around one end of the second fixing frame 7. After the foam solidifies, solid expanding foam 22 is obtained, and one end of the second fixing frame 7 is fixed by the expanding foam 22.

[0140] For some embodiments of this application, please refer to Figure 4 In the second direction, the distance between the cell 2111 and the sidewall of the receiving cavity 12 is greater than the distance between two adjacent cells 2111.

[0141] The distance between the battery cell 2111 and the side wall of the receiving cavity 12 should not be too small to prevent the battery cell 2111 from being squeezed and failing.

[0142] For some embodiments of this application, please refer to Figure 4 In the first direction, the spacing between two adjacent cells 2111 is 2.5mm to 3.5mm.

[0143] In the first direction, the spacing between two adjacent cells 2111 is the spacing between two adjacent cell layers 211. If the spacing is too small, it will increase the foaming resistance, thereby reducing the foaming uniformity of the foaming adhesive 22; while if the spacing is too large, it will lead to an increase in the size of the cell assembly 21, which is not conducive to improving the volumetric energy density of the battery pack 100.

[0144] As an example, in the first direction, the spacing between two adjacent cells 2111 is 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm or 3.5mm.

[0145] The above settings allow the battery pack 100 to maximize the foaming uniformity of the foaming adhesive 22 while ensuring energy density.

[0146] For some embodiments of this application, please refer to Figure 4In two adjacent cell layers 211, the difference between the spacing between two adjacent cells 2111 in the cell layer 211 closer to the opening 11 and the spacing between two adjacent cells 2111 in the cell layer 211 farther from the opening 11 is 0.8mm to 1.2mm.

[0147] The above settings make it easier for the foaming material to expand towards the opening 11 during foaming, thereby improving the foaming uniformity of the foam 22 and making the surface of the foam 22 flat or nearly flat.

[0148] For some embodiments of this application, please refer to Figure 4 The number of battery cell layers 211 in the battery cell group 21 is two layers. The distance between two adjacent battery cells 2111 in the top battery cell layer 211 is 3.5mm to 4.5mm, and the distance between two adjacent battery cells 2111 in the bottom battery cell layer 211 is 2.5mm to 3.5mm.

[0149] The battery pack 100 obtained by the above settings has a compact structure and the foaming uniformity of the foaming adhesive 22 is good.

[0150] As an example, the distance between two adjacent cells 2111 in the top cell layer 211 is 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm or 4.5mm.

[0151] As an example, the distance between two adjacent cells 2111 in the bottom cell layer 211 is 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm or 3.5mm.

[0152] In some embodiments of this application, the battery pack 100 is a low-voltage battery pack 100, and the output voltage of the low-voltage battery pack 100 is less than or equal to 48V. As an example, the battery pack 100 can be a 12V low-voltage battery pack, a 24V low-voltage battery pack, or a 48V low-voltage battery pack.

[0153] In some embodiments of this application, the low-voltage battery pack is a starter battery pack. A starter battery pack, also known as a starting power supply, is a power device used to provide initial power to a device or system to start its operation. As an example, a starter battery pack includes an automotive starter power supply.

[0154] For some embodiments of this application, please refer to Figure 1 The battery pack 100 also includes a cover 8, which covers the housing 1 to close the opening 11, thereby forming a closed receiving cavity 12. The battery module 2 is disposed in the receiving cavity 12, and the housing 1 and the cover 8 together protect the battery module 2.

[0155] Secondly, embodiments of this application also provide a method for preparing a battery pack 100, comprising:

[0156] A housing 1 is provided, one end of which has an opening 11 and an internal receiving cavity 12 that communicates with the opening 11.

[0157] A battery cell assembly 21 is provided, the battery cell assembly 21 includes a plurality of battery cell layers 211 that are spaced apart sequentially along a first direction, each battery cell layer 211 includes a plurality of battery cells 2111 that are spaced apart sequentially along a second direction, the battery cells 2111 extending along a third direction, wherein the first direction, the second direction and the third direction intersect each other.

[0158] The battery cell assembly 21 is placed in the receiving cavity 12 through the opening 11, with the first direction being from the bottom wall of the receiving cavity 12 to the opening 11, and the battery cell assembly 21 is spaced apart from the inner wall of the receiving cavity 12. In two adjacent battery cell layers 211, the spacing between two adjacent battery cells 2111 in the battery cell layer 211 closer to the opening 11 is greater than the spacing between two adjacent battery cells 2111 in the battery cell layer 211 farther from the opening 11.

[0159] Foaming material is provided and injected into the bottom wall of the receiving cavity 12 through the opening 11. After foaming, the foaming material fills the inside of the cell assembly 21 and the space between the cell assembly 21 and the inner wall of the receiving cavity 12 and is cured to form foaming material 22, thus obtaining the battery module 2.

[0160] Since the foaming material expands from the bottom wall of the cavity 12 towards the opening 11 during foaming, the direction of expansion of the foaming material is opposite to the direction of gravity. The closer to the opening 11, the less foaming material there is due to gravity. However, by setting the battery cell group 21 in the cavity 12 to be in two adjacent battery cell layers 211, the spacing between two adjacent battery cells 2111 in the battery cell layer 211 closer to the opening 11 is greater than the spacing between two adjacent battery cells 2111 in the battery cell layer 211 farther from the opening 11, the foaming resistance of the foaming material can be reduced in the direction closer to the opening 11. This can alleviate the problem of reduced foaming caused by gravity to a certain extent, thereby improving the uniformity of the obtained foaming material 22.

[0161] In some embodiments of this application, the method for preparing the battery pack 100 described above is used to prepare the battery pack 100 provided in the first aspect.

[0162] In some embodiments of this application, injecting the expanding foam material into the bottom wall of the receiving cavity 12 through the opening 11 specifically involves: injecting the expanding foam material into the bottom wall of the receiving cavity 12 through the gap between two adjacent battery cells 2111 in the middle of the battery cell layer 211, and reciprocating along a third direction. Typically, the expanding foam material begins to foam within 3 to 5 minutes after injection into the receiving cavity 12. By injecting the expanding foam material into the receiving cavity 12 in the above manner, the paths of the injected expanding foam material to the two side walls of the receiving cavity 12 are made closer, thereby resulting in more uniform foaming of the expanding foam material.

[0163] Thirdly, please see Figure 17 This application provides an electrical device 200, which includes the battery pack 100 as described above or the battery pack 100 prepared by the method described above.

[0164] The power device 200 includes the aforementioned battery pack 100, and the power device 200 has all the beneficial effects of the aforementioned battery pack 100, which will not be repeated here.

[0165] It should be noted that the electrical device 200 includes, but is not limited to, at least one of a vehicle and a processing tool. For example, a vehicle includes a vehicle, an aircraft, etc.; a processing tool includes an electric drill, an electric screwdriver, etc.

[0166] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A battery pack (100), characterized in that, include: A housing (1), wherein one end of the housing (1) has an opening (11) and an internal cavity (12) communicating with the opening (11); and A battery module (2) is disposed within the receiving cavity (12); the battery module (2) includes a cell assembly (21) and a foam adhesive (22), the cell assembly (21) being spaced apart from the inner wall of the receiving cavity (12), and the foam adhesive (22) filling the interior of the cell assembly (21) and the space between the cell assembly (21) and the inner wall of the receiving cavity (12); the cell assembly (21) includes a plurality of cell layers (211) spaced apart sequentially along a first direction, and each cell layer (211) includes a plurality of cells (211) spaced apart sequentially along a second direction. 1) The battery cell (2111) extends along a third direction, wherein the first direction, the second direction and the third direction intersect each other, and the first direction is the direction from the bottom wall of the receiving cavity (12) to the opening (11); the battery pack (100) also includes at least one boss (3), the boss (3) protrudes from the bottom wall surface of the receiving cavity (12), the surface of the boss (3) facing the battery cell group (21) is a contoured surface (31), and the distance between the contoured surface (31) of each boss (3) and the battery cell group (21) is equal.

2. The battery pack (100) according to claim 1, characterized in that, The distance between the contoured surface (31) of each of the aforementioned bosses (3) and the battery cell assembly (21) is 1 mm to 2 mm; and / or, The battery cell (2111) is a cylindrical battery cell (2111), and the contoured surface (31) is an arc surface; and / or, The boss (3) extends along the third direction, and in the third direction, the ratio of the length of the boss (3) to the length of the cell (2111) is greater than or equal to 0.

5.

3. The battery pack (100) according to claim 1 or 2, characterized in that, The battery module (2) further includes a pair of brackets (23) spaced apart on the third side, the battery cell group (21) is located between the pair of brackets (23), and both ends of each battery cell (2111) are connected to the pair of brackets (23).

4. The battery pack (100) according to claim 3, characterized in that, The bracket (23) includes a first plate (231) that stands upright on the bottom wall of the receiving cavity (12) and corresponds to the side wall of the receiving cavity (12). A limiting groove (2311) is formed on the first plate (231). The end of the battery cell (2111) is inserted into the limiting groove (2311) and is limited and engaged by the limiting groove (2311).

5. The battery pack (100) according to claim 4, characterized in that, The end of the battery cell (2111) has an explosion-proof valve (2112) and a pole post (2113). The bottom wall of the limiting groove (2311) is provided with a first clearance hole (2312) and a second clearance hole (2313). The explosion-proof valve (2112) corresponds to the first clearance hole (2312), and the pole post (2113) corresponds to the second clearance hole (2313).

6. The battery pack (100) according to claim 5, characterized in that, The sidewall of the receiving cavity (12) is provided with a first support rib (13) and a second support rib (14) extending from the bottom wall of the receiving cavity (12) to the opening (11). The first support rib (13) and the second support rib (14) abut against the side surface of the first plate (231) away from the battery cell assembly (21). The first support rib (13), the second support rib (14) and the first plate (231) divide the receiving cavity (12) into an independent first sub-cavity (121) and a second sub-cavity (122). The battery cell assembly (21) and the foam (22) are located in the first sub-cavity (121). The first clearance hole (2312) and the second clearance hole (2313) are both connected to the second sub-cavity (122).

7. The battery pack (100) according to claim 6, characterized in that, The battery pack (100) also includes a busbar (4) which extends at least partially into the second sub-cavity (122) and is connected to the terminal post (2113).

8. The battery pack (100) according to claim 7, characterized in that, The first plate (231) has a limiting post (2314) protruding on the side surface opposite to the battery cell assembly (21). The busbar (4) has a limiting hole (41). The limiting post (2314) is inserted into the limiting hole (41) and is limited and engaged with the limiting hole (41).

9. The battery pack (100) according to any one of claims 4 to 8, characterized in that, The bracket (23) further includes a second plate (232), which is disposed at one end of the first plate (231) near the opening (11), and the second plate (232) is disposed at an angle to the first plate (231) and extends above the battery cell assembly (21); The battery pack (100) also includes a battery management system module (5), which is disposed on the second plate (232) and electrically connected to the battery cell (2111).

10. The battery pack (100) according to any one of claims 1 to 8, characterized in that, The battery pack (100) also includes a first fixing frame (6) and a battery management system module (5). One end of the first fixing frame (6) is inserted and fixed to the foam (22), and the other end of the first fixing frame (6) is located above the cell group (21). The battery management system module (5) is disposed on the other end of the first fixing frame (6) and electrically connected to the cell (2111).

11. The battery pack (100) according to any one of claims 1 to 10, characterized in that, The battery pack (100) also includes a second fixing frame (7) and a busbar (4). One end of the second fixing frame (7) is inserted and fixed to the foam (22), and the other end of the second fixing frame (7) is located above the battery cell group (21). The busbar (4) is disposed on the other end of the second fixing frame (7) and connected to the battery cell (2111).

12. The battery pack (100) according to any one of claims 1 to 11, characterized in that, In the second direction, the distance between the battery cell (2111) and the sidewall of the receiving cavity (12) is greater than the distance between two adjacent battery cells (2111); and / or, In the first direction, the spacing between two adjacent cells (2111) is 2.5mm to 3.5mm; and / or, The battery pack (100) further includes a cover (8) that covers the housing (1) to close the opening (11); and / or, The battery pack (100) is a low-voltage battery pack (100), and the output voltage of the low-voltage battery pack (100) is less than or equal to 48V.

13. An electrical appliance (200), characterized in that, Includes the battery pack (100) as described in any one of claims 1 to 12.

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