Battery pack

Abstract

In the battery pack provided by the present disclosure, by providing the step surface on the inner bottom surface of the housing, at least two arrangement regions with a height difference can be formed in the housing, so that an acting force can be applied to the adhesive located in the arrangement region with a higher height, thereby helping the adhesive to flow to the arrangement region with a lower height. It is beneficial to improve the fluidity of the adhesive in the case, so that the adhesive can be more easily and sufficiently filled in each region of the case, and it is beneficial to make the surface of the adhesive inside the case smoother, so that a plurality of battery cells in different regions in the case are more easily immersed in the adhesive, which is beneficial to the assembly of the battery pack.SOLUTION: The present invention provides a battery pack including: a plurality of battery cells; and a case having a stepped surface on an inner bottom surface, the inner bottom surface being divided into at least two arrangement regions having a height difference in a height direction, the battery cells being arranged in each of the arrangement regions.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to the technical field of power batteries, and in particular to battery packs. [Background technology]

[0002] In the related art, a conventional battery pack includes a conventional case and a plurality of battery cells mounted in the conventional case. After the battery cells are assembled in the conventional case, adhesive is injected from the top of the conventional battery pack to immerse and seal the battery cells in the conventional case. However, there may be a problem that the adhesive has poor flowability within the case, and the adhesive cannot completely soak all the battery cells within the conventional case. Therefore, how to improve the fluidity of the adhesive inside the case has become an issue that needs to be resolved as soon as possible. Summary of the Invention [Problem to be solved by the invention]

[0003] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a battery pack in which the fluidity of the adhesive inside the case is improved. [Means for solving the problem]

[0004] Based on the above object, the present invention provides a battery pack comprising a plurality of battery cells and a case having a stepped surface on the inner bottom surface, dividing the inner bottom surface into at least two placement areas with a difference in height in the vertical direction, and in which the battery cells are placed in each of the placement areas.

[0005] In one embodiment of the present invention, the case comprises a bottom plate and a support member, has a storage space inside the bottom plate, the support member is arranged within the storage space, and the plate surface of the support member facing away from the bottom plate is configured as the inner bottom surface of the case.

[0006] In one embodiment of the present invention, the support member is spaced apart from the bottom plate, and an exhaust passage is defined between the bottom plate and the support member; the battery cells have anti-explosion valves, which face the inner bottom surface of the case; and exhaust holes corresponding to the anti-explosion valves are provided on the inner bottom surface of the case, which pierce the support member and communicate with the exhaust passage, so that gas discharged from the anti-explosion valves can pass through the exhaust holes and enter the exhaust passage.

[0007] In one embodiment of the present invention, the support member includes at least two support sub-plates, and the plate surface of each support sub-plate away from the bottom plate constitutes one of the placement areas, and at least one separator is provided between each support sub-plate and the bottom plate along a first direction, the separator divides the exhaust passage into at least two exhaust sub-passages, and two adjacent exhaust sub-passages are sequentially connected to each other, and the first direction is perpendicular to the plate surface of the support sub-plate.

[0008] In one embodiment of the present invention, the separator has a free end, and an exhaust communication hole is defined between the free end of the separator and the adjacent inner wall of the case, and / or an exhaust communication hole is defined between the free end of the separator and the adjacent support member, and adjacent exhaust sub-passages are connected through the exhaust communication hole.

[0009] In one embodiment of the present invention, the number of the separators below each of the support sub-plates increases in sequence along the second direction, and the second direction is a direction in which the height of the arrangement region gradually increases.

[0010] In one embodiment of the present invention, the separator adjacent to the support subplate along the first direction is defined as the first separator, and along the second direction, the lower plate surface of the support subplate is not higher than the upper plate surface of the first separator of the adjacent support subplate on the front side.

[0011] In one embodiment of the present invention, the lower plate surface of the support sub-plate is flush with the lower plate surface of the first separator of the adjacent support sub-plate on the front side along the second direction.

[0012] In one embodiment of the present invention, an orthogonal projection of the separator onto the corresponding support sub-plate along the first direction covers at least an exhaust hole provided in the support sub-plate.

[0013] In one embodiment of the present invention, the separator is connected to the support member and / or the inner wall of the case.

[0014] In one embodiment of the present invention, a sealing layer covering the battery cells is provided above each placement area, and the thickness of the sealing layer corresponding to each placement area increases sequentially along the direction opposite to the second direction, and the second direction is the direction in which the height of the placement area gradually increases.

[0015] In one embodiment of the present invention, the sealing layer has a top surface, the top surface of the sealing layer is spaced apart from the inner bottom surface of the case, and the top surface of the sealing layer corresponding to at least a portion of the placement area is flush with the top surface of the sealing layer. [Effects of the Invention]

[0016] As can be seen from the above, the battery pack provided by the present invention has a stepped surface on the inner bottom surface of the case, which allows at least two placement areas with different heights to be formed within the case, and applies a force to the adhesive located in the higher placement area, helping the adhesive to flow to the lower placement area. This contributes to improving the flowability of the adhesive within the case, making it easier for the adhesive to be fully filled into each area of ​​the case, contributing to forming a flatter adhesive surface inside the case, making it easier for multiple battery cells in different areas of the case to be submerged by the adhesive, and facilitating the assembly of the battery pack. [Brief explanation of the drawings]

[0017] In order to more clearly describe the technical solutions of the present invention or related art, the following briefly describes the drawings that need to be used in the description of the embodiments or related art. The drawings described below are only embodiments of the present invention, and it is obvious to those skilled in the art that other drawings can be obtained based on these drawings without any creative work.

[0018] [Figure 1] 1 is a schematic three-dimensional view of a partial structure of a battery pack according to an embodiment of the present invention. [Figure 2] 1 is a top view of a partial structure of a battery pack according to an embodiment of the present invention. [Figure 3] 1 is a schematic three-dimensional view of a case of a battery pack according to an embodiment of the present invention; [Figure 4] FIG. 3 is a cross-sectional schematic view taken along the line AA in FIG. 2. [Figure 5] 3 is a schematic cross-sectional view of the AA cross section of FIG. 2 after removing the battery cell. [Figure 6] FIG. 6 is an enlarged schematic view of part B in FIG. 5. [Figure 7] FIG. 6 is an enlarged schematic view of part C in FIG. 5. [Figure 8] FIG. 6 is an enlarged schematic view of part D in FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clearly understandable, the present invention will be described in more detail below in combination with specific embodiments and with reference to the drawings. It should be noted that the relative arrangement of components, numerical expressions, and numerical values ​​described in these embodiments do not limit the scope of the present invention unless otherwise specifically stated. At the same time, it should be understood that for the sake of convenience, the sizes of the parts shown in the drawings are not drawn according to their actual proportions.

[0020] The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention and its application or uses. It should be noted that unless otherwise defined, technical or scientific terms used in the embodiments of the present invention shall have the ordinary meanings understood by those skilled in the art. The terms "first," "second," and similar terms used in the embodiments of the present invention do not denote order, quantity, or importance, but are used only to distinguish between different components. Similar terms such as "comprises" and "has" mean that the element or thing preceding the term includes the element or thing listed thereafter and their equivalents, but does not exclude other elements or things. Similar terms such as "connected" and "coupled" are not limited to physical or mechanical connections, but also include electrical connections, whether direct or indirect. Terms such as "top," "bottom," "left," and "right" are used only to indicate relative positional relationships, and if the absolute position of the described object changes, the relative positional relationships may also change accordingly.

[0021] Referring to FIG. 1, FIG. 1 shows a three-dimensional schematic diagram of a partial structure of a battery pack. The battery pack includes a case 100. The case 100 includes a bottom plate 20 and four side plates 40 connected to edges of the bottom plate 20. The bottom plate 20 and the four side plates 40 define an accommodation space 30 located inside the case 100. A case explosion-proof valve 41 is attached to at least one side plate 40 of the case 100. For example, the case explosion-proof valve 41 is attached to the side plate 40 along the width direction of the case (such as the X direction in FIG. 1). The battery pack further includes a plurality of battery cells 210 attached within the accommodation space 30. The battery cells 210 may be cylindrical battery cells.

[0022] Referring to Figure 2, Figure 2 shows a top view of a partial structure of a battery pack. Taking the structure shown in Figure 2 as an example, a plurality of battery cells 210 can form a plurality of battery cell arrays 200, and the plurality of battery cell arrays 200 are distributed along the width direction of the case 100 (such as the X direction in Figure 2). Each battery cell array 200 includes a plurality of battery cells 210 distributed along the length direction of the case 100 (such as the Y direction in Figure 2). To improve the space utilization rate of the accommodation space 30, adjacent battery cell arrays 200 can be arranged in a staggered manner.

[0023] In some embodiments, one horizontal support plane is provided in the accommodation space 30 of the case 100. For example, this support plane may be formed by the inner surface of the bottom plate 20 of the case 100 or by the surface of a structural member attached to the accommodation space 30 of the case 100. All of the battery cells 210 in the accommodation space 30 are disposed on this support plane. When an adhesive is injected into the case 100 from the top of the battery pack, the adhesive (e.g., potting adhesive) must flow downward onto the support plane and then flow in all directions of the support plane, filling the accommodation space 30 until all of the battery cells 210 in the accommodation space 30 are submerged.

[0024] However, the applicant discovered that the adhesive itself has high viscosity, and when it flows along a horizontal support plane, the support plane cannot provide any force to assist the adhesive flow, which makes it easy for stagnation to occur during the adhesive flow process, resulting in adhesive accumulation in some areas of the storage space, resulting in a high adhesive surface height in those areas, and a lack of adhesive in other areas, resulting in a low adhesive surface height in those areas, making it difficult to form a flat horizontal adhesive surface in the case. If the adhesive surface height is uneven, it is difficult to ensure that multiple battery cells in different areas of the case are completely submerged, and this is likely to adversely affect the subsequent assembly of the battery pack.

[0025] With this in mind, and referring to Fig. 1, one embodiment of the present invention provides a battery pack including a case 100 and a plurality of battery cells 210. Referring to Fig. 3, Fig. 3 shows a three-dimensional schematic view of the case 100. The inner bottom surface 10 of the case 100 has a stepped surface, which divides the inner bottom surface 10 of the case 100 into at least two arrangement areas 11 having a difference in height in the height direction of the case 100 (such as the Z direction in Fig. 3), and a battery cell 210 is arranged in each arrangement area 11.

[0026] For example, the battery cell 210 according to this embodiment may be a cylindrical battery cell or a prismatic case battery cell.

[0027] For example, the step surface of the inner bottom surface 10 of the case 100 may be formed by a bottom plate 20 of non-uniform thickness, or may be formed by a structural member of non-uniform thickness (e.g., a plate-shaped structural member or a block-shaped structural member) attached to the inside of the case 100, or may be formed by a plate-shaped structural member of uniform thickness with a step shape attached to the inside of the case 100.

[0028] For example, the height of the placement region 11 may gradually increase in one direction, such as gradually increasing from one side to the other along the width direction of the case 100. Alternatively, the height of the placement region 11 may gradually increase in two opposing directions, such as gradually increasing from the center of the case 100 toward both sides along the width direction of the case 100. Furthermore, the height of the placement region 11 may gradually increase from the center of the case 100 toward the edges along the width and length directions of the case 100.

[0029] For example, the surface areas of the placement regions 11 may be the same or different, and the surface shapes of the placement regions 11 may be the same or different.

[0030] For example, the height differences between any two adjacent placement areas 11 may or may not be equal.

[0031] The inner bottom surface 10 of the case 100 has a stepped surface, allowing adhesive to be injected from the highest placement area 11. When the adhesive flows from the highest placement area 11 to the lower placement area 11, the difference in elevation between the two placement areas 11 converts the gravitational energy of the adhesive into kinetic energy, promoting the flow of the adhesive. At the same time, even if adhesive is present on the surface of each placement area 11, as long as there is a difference in elevation on the adhesive surface, this can have an assisting effect on the flow of adhesive injected into the case 100 later until the adhesive surface inside the case 100 forms a flat surface.

[0032] In a battery pack provided by an embodiment of the present invention, the inner bottom surface 10 of the case 100 has a stepped surface, which allows at least two placement areas 11 with different heights to be formed within the case 100, and applies force to the adhesive in the higher placement area 11, helping the adhesive to flow to the lower placement area 11. This contributes to improving the flowability of the adhesive within the case 100, making it easier for the adhesive to be fully filled into each area of ​​the case 100, contributing to forming a flatter adhesive surface within the case 100, making it easier for multiple battery cells 210 in different areas within the case 100 to be submerged by the adhesive, and facilitating the assembly of the battery pack.

[0033] 4, which shows a schematic cross-sectional view of the AA cross section of FIG. 2. In some embodiments, the case 100 includes a bottom plate 20 and a support member 300, and has an accommodation space 30 inside the bottom plate 20. The support member 300 is provided in the accommodation space 30, and the plate surface of the support member 300 away from the bottom plate 20 is configured as the inner bottom surface 10 of the case 100.

[0034] For example, the support member 300 may be a stepped plate structure with a uniform thickness, or may be a stepped block structure with a non-uniform thickness.

[0035] For example, the support member 300 may be fixedly or detachably connected to the bottom plate 20 of the case 100, and the support member 300 may be fixedly or detachably connected to the side plate 40 of the case 100.

[0036] For example, a fixed connection between the support member 300 and the case 100 may be achieved by methods such as welding, adhesive bonding, or integral molding, and a detachable connection between the support member 300 and the case 100 may be achieved by methods such as engagement, insertion, or fastening.

[0037] By configuring the surface of the support member 300, which is independent from the bottom plate 20, as a stepped surface on the inner bottom surface 10 of the case 100, the bottom plate 20 of the case 100 can be maintained in a thin plate-like structure with a uniform thickness, which contributes to simplifying the overall structure of the case 100 and also contributes to reducing the cost of the case 100.

[0038] Referring to FIG. 4 , in some embodiments, the support member 300 is spaced apart from the bottom plate 20, and an exhaust passage 400 is defined between the bottom plate 20 and the support member 300, the battery cells 210 have battery cell explosion-proof valves 211, and the battery cell explosion-proof valves 211 face the inner bottom surface 10 of the case 100, and exhaust holes 310 corresponding to the battery cell explosion-proof valves 211 are provided on the inner bottom surface 10 of the case 100, and the exhaust holes 310 pass through the support member 300 and communicate with the exhaust passage 400, so that gas discharged from the battery cell explosion-proof valves 211 can pass through the exhaust holes 310 and enter the exhaust passage 400.

[0039] For example, the mounting position of the case explosion-proof valve 41 on the side panel 40 corresponds to the exhaust passage 400, and when the case explosion-proof valve 41 is opened, the exhaust passage 400 can pass through the case explosion-proof valve 41 and communicate with the outside of the case 100.

[0040] For example, the battery cell explosion-proof valve 211 is located at the bottom of the battery cell 210 .

[0041] For example, the circumferential side walls of the support member 300 are all bonded and connected to the inner wall 42 of the case 100, improving the sealing performance between the exhaust passage 400 and the space in which the battery cells are arranged.

[0042] For example, the support member 300 may be a plate-like structure of uniform thickness to facilitate vent holes 310 passing through the support member 300 .

[0043] The support member 300 can divide the battery cell arrangement space within the storage space 30 that houses the battery cells 210 located above the support member 300 from the exhaust passage 400 located below the support member 300, and can prevent gas from the exhaust passage 400 from entering the battery cell arrangement space to a certain extent, thereby reducing the adverse effects that gas discharged from the battery cell explosion-proof valve 211 has on other battery cells 210.

[0044] The applicant has found through research that when thermal runaway occurs in a battery cell 210 (especially a cylindrical battery cell), the weight of the battery cell 210 decreases significantly (the weight loss exceeds 80% of the original weight of the battery cell 210). The reason for this significant weight loss in the battery cell 210 is that when thermal runaway occurs in the battery cell 210, the gas discharged from the battery cell explosion-proof valve 211 carries a large amount of solid particles. The particles carried by the gas flow through the exhaust passage 400 toward the case explosion-proof valve 41. Upon reaching the case explosion-proof valve 41, the gas passes through the case explosion-proof valve 41 and is discharged from the case 100. However, at least some of the particles pass through the case explosion-proof valve 41 and are not smoothly discharged from the case 100. These particles tend to clog the case explosion-proof valve 41, preventing later-arriving gas from passing through the case explosion-proof valve 41 and being discharged from the case 100, posing a risk of thermal diffusion and ignition / combustion in the battery pack.

[0045] In some embodiments, a screen is provided to block particles carried in the gases flowing through the exhaust passage 400 .

[0046] The screen can block particles in the gas before the gas flows into the case explosion-proof valve 41, reducing to a certain extent the risk of particles clogging the case explosion-proof valve 41. However, if the screen blocks a large number of particles, there is a risk that the mesh of the screen will become clogged with particles, which will also have a serious adverse effect on the flow of gas in the exhaust passage 400.

[0047] With this in mind, reference is made to FIG. 5, which shows a schematic cross-sectional view of the AA cross section of FIG. 2 after removing the battery cells 210. In some embodiments, the support member 300 includes at least two support sub-plates 320, and the surface of each support sub-plate 320 away from the bottom plate 20 defines one placement area 11. At least one separator 500 is provided between each support sub-plate 320 and the bottom plate 20 along a first direction (such as the Z direction in FIG. 5). Reference is made to FIG. 6, which is an enlarged schematic view of portion B in FIG. 5. The separator 500 divides the exhaust passage 400 into at least two exhaust sub-passages 410, and two adjacent exhaust sub-passages 410 are sequentially connected to each other. The first direction is perpendicular to the surface of the support sub-plates 320.

[0048] For example, at least two layers of separators 500 are provided along the first direction below each support sub-plate 320. This allows for even if the closest layer of separators 500 below the support sub-plate 320 is damaged (for example, if the separator 500 is punctured by gas ejected from the battery cell explosion-proof valve 211), the separators 500 below the damaged separator 500 can still play a role in dividing the exhaust passage 400.

[0049] For example, a connecting portion 330 is provided between two adjacent support sub-plates 320, and each connecting portion 330 is fixedly connected to the two support sub-plates 320. The connecting portion 330 allows the two adjacent support sub-plates 320 to be configured as a continuous plate-like structure.

[0050] For example, the connection between the connecting portion 330 and the supporting sub-plate 320 can be fixedly connected by welding, integral molding or the like.

[0051] For example, referring to FIG. 6, the connecting portion 330 may be a plate-like structure, and the angle d between the plate surface of the connecting portion 330 and the plate surface of the supporting sub-plate 320 is 90° or more.

[0052] Along the first direction, the separator 500 divides the exhaust passage 400 into at least two exhaust sub-passages 410, and two adjacent exhaust sub-passages 410 are sequentially connected to each other, and the gas flow direction changes at the position where the two adjacent exhaust sub-passages 410 are connected to each other.

[0053] Specifically, taking the structure and direction of FIG. 6 as an example, the dotted arrows in the figure indicate the gas flow path. Gas flows from right to left in the first exhaust subpassage 410a. When the gas flow reaches the connection point between the upper first exhaust subpassage 410a and the lower second exhaust subpassage 410b, the gas flow direction changes and flows from left to right into the second exhaust subpassage 410b, continuing to flow into the case explosion-proof valve 41. It can be seen that when the gas flow direction changes, the gas flow rate decreases, and the energy with which the gas carries particles also decreases. When particles accumulate at the point where the gas flow direction changes, separation of the gas and solids occurs. The number of particles carried by the gas flowing into the second exhaust subpassage 410b decreases, contributing to a reduction in the risk of the case explosion-proof valve 41 being clogged by particles.

[0054] Referring to Figure 7, Figure 7 shows an enlarged schematic view of portion C of Figure 5. In some embodiments, separator 500 has a free end 520, and an exhaust communication hole 420 is defined between free end 520 of separator 500 and the adjacent inner wall 42 of case 100, and adjacent exhaust sub-passages 410 are in communication with each other via exhaust communication hole 420.

[0055] And / or, referring to FIG. 6, an exhaust communication hole 420 is defined between the free end 520 of the separator 500 and the adjacent support member 300, and adjacent exhaust sub-passages 410 are in communication with each other via the exhaust communication hole 420.

[0056] For example, in the circumferential direction of the separator 500, one end of the separator 500 that is not connected to another structural member is defined as the free end 520.

[0057] For example, the inner wall 42 of the case 100 is the plate surface of the side plate 40 facing the accommodation space 30 .

[0058] By forming the exhaust communication hole 420 with the separator 500 spaced apart from the inner wall 42 of the case 100, or by forming the exhaust communication hole 420 with the separator 500 and the support member 300 spaced apart, the exhaust communication hole 420 covers the entire edge of the free end 520 of the separator 500, which increases the opening area of ​​the exhaust communication hole 420 and further reduces the risk of the exhaust communication hole 420 being blocked by accumulated particles. Furthermore, compared to a method of forming the exhaust communication hole 420 by removing material from the separator 500, the method of forming the exhaust communication hole 420 of this embodiment simplifies the internal structure of the case 100 and reduces the difficulty of processing and the cost of the case 100.

[0059] Referring to FIG. 5, in some embodiments, the number of separators 500 below each support subplate 320 increases sequentially along a second direction (such as the X direction in FIG. 5), and the second direction is the direction in which the height of the placement area 11 gradually increases.

[0060] For example, each of the two side plates 40 of the case 100 along the second direction is provided with a case explosion-proof valve 41 .

[0061] For example, a cavity 43 is provided inside the side plate 40 of the case 100, and the case explosion-proof valve 41 extends into the cavity 43. A through-hole is provided in the inner wall 42 of the case 100, and an exhaust sub-passage 410 located at least in the bottom layer along the height direction of the case 100 communicates with the cavity 43 via this through-hole.

[0062] The thickness of the multiple support sub-plates 320 is the same, and as the height of the arrangement area 11 increases, the cross-sectional height of the exhaust passage 400 between the support sub-plate 320 and the bottom plate 20 of the case 100 also increases accordingly. By increasing the number of separators 500, the exhaust passage 400 can be divided into more exhaust sub-passages 410, and the number of exhaust communication holes 420 also increases accordingly. As gas flows through more exhaust communication holes 420, the number of accumulated particles also increases, further reducing the risk of the case explosion-proof valve 41 being blocked.

[0063] Referring to Figure 6, in some embodiments, along a first direction (such as the Z direction in Figure 6), the separator 500 adjacent to the support subplate 320 is defined as the first separator 510, and along a second direction (such as the X direction in Figure 6), the lower plate surface of the support subplate 320 is not higher than the upper plate surface of the first separator 510 of the front adjacent support subplate 320.

[0064] Taking the structure and direction shown in Figure 6 as an example, along the second direction, the second support sub-plate 320b is located in front of the first support sub-plate 320a, and the height of the second support sub-plate 320b is higher than the height of the first support sub-plate 320a.

[0065] Gas passes through the exhaust holes 310 in the first support sub-plate 320a and enters the third exhaust sub-passage 410c, then flows from left to right. When gas flows into the exhaust manifold 420, the upper surface of the first separator 510, which corresponds to the second support sub-plate 320b, is higher than the lower surface of the first support sub-plate 320a. This prevents the first exhaust sub-passage 410a from flowing upward into the first exhaust sub-passage 410a, preventing the gas from adversely affecting the battery cells 210 on the second support sub-plate 320b, which is located higher, and contributing to the prevention of thermal diffusion. After passing through the exhaust manifold 420, the gas flows downward into the second exhaust sub-passage 410b and passes through the case explosion-proof valve 41 near the bottom plate 20 of the case 100 before being discharged to the outside of the case 100.

[0066] Referring to FIG. 6, in some embodiments, the lower plate surface of a support sub-plate 320 is flush with the lower plate surface of the first separator 510 of the adjacent support sub-plate 320 on the front side along the second direction.

[0067] 6 , if the lower surface of the first separator 510 corresponding to the second support sub-plate 320b is flush with the lower surface of the first support sub-plate 320a, the distance between the first exhaust sub-passage 410a and the third exhaust sub-passage 410c in the first direction can be increased, further preventing gas flowing out of the third exhaust sub-passage 410c from entering the first exhaust sub-passage 410a. Furthermore, if the third exhaust sub-passage 410c and the second exhaust sub-passage 410b are arranged opposite each other, gas flowing out of the third exhaust sub-passage 410c can quickly and smoothly enter the second exhaust sub-passage 410b and pass through the case explosion-proof valve 41 near the bottom plate 20 of the case 100, which helps to expel the gas to the outside of the case 100.

[0068] Referring to Figure 8, Figure 8 shows an enlarged schematic view of portion D of Figure 5, and in some embodiments, along a first direction (such as the Z direction in Figure 8), the orthogonal projection of the separator 500 of the corresponding support subplate 320 covers at least the exhaust hole 310 provided in the support subplate 320.

[0069] For example, the exhaust holes 310 of the support sub-plate 320 correspond to the battery cell explosion-proof valves 211 of the battery cells 210 arranged on the support sub-plate 320 , respectively.

[0070] The separator 500 covers all exhaust holes 310 on the corresponding support sub-plate 320, ensuring that after gas passes through any one of the exhaust holes 310 on the support sub-plate 320, the separator 500 will cause the gas to enter the exhaust sub-passage 410, thereby separating the gas from solids as the gas flows through the exhaust sub-passage 410 to the case explosion-proof valve 41, and reducing the risk of particles carried by the gas clogging the case explosion-proof valve 41.

[0071] Referring to FIG. 8, separator 500 is connected to support member 300 and / or the inner wall of case 100 .

[0072] For example, when the separator 500 is connected to the support member 300 , the separator 500 is connected to the connection portion 330 of the support member 300 .

[0073] For example, along the second direction (such as the X direction in Figure 8), one side of the connecting portion 330 is connected to the support sub-plate 320 and the other side is connected to the separator 500, and the lower plate surface of the support sub-plate 320 is flush with the lower plate surface of the separator 500.

[0074] For example, when the separator 500 is connected to the case 100 , the separator 500 is connected to the inner wall 42 of the side plate 40 of the case 100 .

[0075] For example, the separator 500 can be connected to the inner wall of the case 100 or the support member 300 by welding, adhesive, insertion, fastening, or integral molding.

[0076] The support member 300 and / or the inner wall of the case 100 serve as the basic structure for the fixed connection of the separator 500, thereby improving the integrity of the entire battery pack and reducing the difficulty of assembly. In addition, the need for a separate fixing structure for the separator 500 can be eliminated, which contributes to simplifying the internal structure of the case 100 and reducing the cost of the case 100.

[0077] 4, in some embodiments, a sealing layer 600 covering the battery cells 210 is provided above each placement region 11, and the thickness of the sealing layer 600 corresponding to each placement region 11 increases sequentially along the direction opposite to the second direction (such as the X direction in FIG. 4). The second direction is the direction in which the height of the placement region 11 gradually increases.

[0078] For example, the sealing layer 600 can be formed by curing a foam adhesive.

[0079] 4 as an example, the height of the support sub-plates 320 decreases in the direction opposite to the second direction, i.e., from right to left, and correspondingly, the height of the tops of the battery cells 210 disposed on the support sub-plates 320 also decreases in the direction opposite to the second direction. As the height of the tops of the battery cells 210 decreases along the height direction of the case 100 (e.g., the Z direction in FIG. 4), the linear distance between the tops of the battery cells 210 and the top opening of the case 100 increases, and the space for providing the sealing layer 600 also increases.

[0080] The sealing layer 600 covering the top of the battery cell 210 provides a sealing effect to the battery cell 210, helping to prevent exhaust from occurring at the top of the battery cell 210 (in the event of thermal runaway of the battery cell 210) and reducing the risk of an external short circuit. The thicker the sealing layer 600, the better the sealing effect to the battery cell 210.

[0081] 4, in some embodiments, the sealing layer 600 has a top surface 610, which is spaced apart from the inner bottom surface 10 of the case 100, and the top surfaces 610 of the sealing layers 600 corresponding to at least some of the placement areas 11 are flush with each other. Preferably, the top surfaces 610 of all of the sealing layers 600 are flush with each other and configured as a flat surface.

[0082] For example, the top surface 610 of the sealing layer 600 is parallel to the plane in which the top opening of the case 100 lies.

[0083] The sealing layer 600 is a fluid adhesive before hardening. The inner bottom surface 10 of the case 100 is a stepped surface, which can improve the fluidity of the adhesive within the case 100. If the surface of the adhesive does not form a flat surface, the adhesive at higher positions will continuously flow to lower positions due to the difference in height formed by the stepped surface, and after the flow of the adhesive stops, the surface of the adhesive can form a flat surface.

[0084] In this case, as long as the thickness of the sealing layer 600 covering the top of the tallest battery cell 210 meets the process requirements, the thicknesses of the sealing layers 600 covering the tops of the other battery cells 210 in the case 100 will be thicker, which ensures that the sealing layer 600 effectively seals all of the battery cells 210 in the case 100. At the same time, this helps ensure that the subsequent battery pack assembly process can be carried out smoothly.

[0085] It should be noted that the above describes several embodiments of the present invention. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than the embodiments described above and still achieve desirable results. Also, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve desirable results. In some embodiments, multitasking or parallel processing may also be possible or advantageous.

[0086] Each embodiment of the present invention will be described in a step-by-step manner, with emphasis on the differences between each embodiment and other embodiments, and reference may be made to the same or similar parts between the embodiments.

[0087] The description of the present invention has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and changes will be apparent to those skilled in the art. The embodiments have been chosen and described to better explain the principles and practical applications of the invention and to enable others skilled in the art to understand the invention and to design various embodiments with various modifications to suit particular uses.

[0088] Those skilled in the art should understand that the description of any of the above embodiments is merely illustrative and does not imply that the scope of the present invention (including the claims) is limited to these examples. In accordance with the concept of the present invention, the technical features of the above embodiments or different embodiments can be combined, steps can be performed in any order, and there are many other variations in different aspects of the above embodiments of the present invention, which are not described in detail for the sake of brevity.

[0089] While the present invention has been described in conjunction with specific embodiments thereof, many permutations, modifications and variations of these embodiments will be apparent to those skilled in the art in light of the foregoing description.

[0090] The embodiments of the present invention are intended to include all replacements, modifications, and variations that fall within the broad scope of the appended claims. Therefore, all omissions, modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the embodiments of the present invention should also be included in the protection scope of the present invention. [Industrial Applicability]

[0091] The battery pack of the present invention has a stepped surface on the inside bottom surface of the case, which contributes to improving the fluidity of the adhesive within the case, making it easier for the adhesive to be fully filled into each area of ​​the case, and making it easier for multiple battery cells in different areas within the case to be submerged in the adhesive, thereby contributing to the assembly work of the battery pack. [Explanation of symbols]

[0092] 100 cases 10 Inner bottom surface 11 Placement area 20 Bottom plate 30 Containment Space 40 Side panel 41 Case explosion-proof valve 42 Inner wall 43 Cavity 200 battery cell array 210 battery cells 211 Battery cell explosion prevention valve 300 Support member 310 Exhaust vent 320 Support Subplate 320a First supporting subplate 320b Second supporting subplate 330 Connection 400 exhaust passage 410 Exhaust sub-passage 410a First exhaust sub-passage 410b Second exhaust sub-passage 410c Third exhaust sub-passage 420 Exhaust communication hole 500 separator 510 First separator 520 Free end 600 sealing layer 610 Top surface

Claims

1. A plurality of battery cells; a case having a stepped surface on an inner bottom surface, the inner bottom surface being divided into at least two arrangement areas having a height difference in a height direction, the battery cells being arranged in each of the arrangement areas; A battery pack comprising:

2. 2. The battery pack according to claim 1, wherein the case comprises a bottom plate and a support member, has an accommodation space inside the bottom plate, the support member is provided within the accommodation space, and the plate surface of the support member away from the bottom plate is configured as the inner bottom surface of the case.

3. 3. The battery pack according to claim 2, wherein the support member is spaced apart from the bottom plate, defining an exhaust passage between the bottom plate and the support member, the battery cells have anti-explosion valves, the anti-explosion valves face an inner bottom surface of the case, and exhaust holes corresponding to the anti-explosion valves are provided on the inner bottom surface of the case, the exhaust holes penetrate the support member and communicate with the exhaust passage, and gas discharged from the anti-explosion valves can pass through the exhaust holes and enter the exhaust passage.

4. 4. The battery pack of claim 3, wherein the support member includes at least two support sub-plates, a surface of each support sub-plate away from the bottom plate defining one of the placement areas, at least one separator is provided between each support sub-plate and the bottom plate along a first direction, the separator divides the exhaust passage into at least two exhaust sub-passages, and two adjacent exhaust sub-passages are sequentially connected to each other, and the first direction is perpendicular to the surface of the support sub-plates.

5. 5. The battery pack according to claim 4, wherein the separator has a free end, and an exhaust communication hole is defined between the free end of the separator and an adjacent inner wall of the case, and / or an exhaust communication hole is defined between the free end of the separator and an adjacent support member, and adjacent exhaust sub-passages communicate with each other through the exhaust communication hole.

6. 5. The battery pack of claim 4, wherein the number of separators below each support sub-plate increases sequentially along the second direction, and the second direction is a direction in which the height of the placement area gradually increases.

7. 7. The battery pack of claim 6, wherein the separator adjacent to the support subplate along the first direction is defined as a first separator, and the lower plate surface of the support subplate along the second direction is not higher than the upper plate surface of the first separator of the adjacent support subplate on the front side.

8. The battery pack according to claim 7 , wherein the lower surface of the support sub-plate is flush with the lower surface of the first separator of the adjacent support sub-plate on the front side along the second direction.

9. 5. The battery pack according to claim 4, wherein an orthogonal projection of the separator onto the corresponding support sub-plate along the first direction covers at least an exhaust hole provided in the support sub-plate.

10. 5. The battery pack according to claim 4, wherein the separator is connected to the support member and / or the inner wall of the case.

11. 2. The battery pack according to claim 1, wherein a sealing layer covering the battery cells is provided above each of the placement areas, the thickness of the sealing layer corresponding to each of the placement areas increases sequentially along the direction opposite to the second direction, and the height of the placement areas gradually increases in the second direction.

12. 12. The battery pack according to claim 11, wherein the sealing layer has a top surface, the top surface of the sealing layer is spaced apart from the inner bottom surface of the case, and the top surface of the sealing layer corresponding to at least a portion of the placement area is flush with the inner bottom surface of the case.

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