Battery cell, battery pack, and vehicle

Abstract

The utility model belongs to battery technical field discloses the electric core shell, electric core shell, battery monomer, battery package and vehicle, among them electric core shell, will include the weight reduction wall of at least one first side wall arc, and will one end of weight reduction wall with one second side wall meet, weight reduction wall sets up as the convex arc structure of outside, can reduce the occupied space of electric core shell corner edge, to reduce the volume of electric core shell, also be favorable to reduce the weight of electric core shell.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a cell housing, a cell shell, a battery cell, a battery pack, and a vehicle. Background Technology

[0002] like Figure 1 As shown, the square battery cell includes a battery cell housing 11' with a top opening, a bare battery cell 12' disposed inside the battery cell housing 11', and a top cover for sealing the top opening of the battery cell housing 11'. The cross-section of the battery cell housing 11' is rectangular, and the cross-section of the bare battery cell 12' is rectangular in the middle and semi-circular at both ends in the length direction. On both sides of the width direction of the bare battery cell 12', the shape difference between the bare battery cell 12' and the battery cell housing 11' results in extra space between them. This extra space will not only increase the volume of the battery cell housing 11', but also increase the weight of the battery cell housing 11'. Utility Model Content

[0003] The purpose of this utility model is to provide a cell housing, a cell outer shell, a battery cell, a battery pack, and a vehicle that can reduce the weight and volume of the cell housing.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A battery cell housing, wherein the battery cell housing has a bare battery cell receiving cavity, and the battery cell housing includes two first sidewalls arranged opposite each other along the X direction, and two second sidewalls arranged opposite each other along the Y direction;

[0006] At least one of the first sidewalls includes a weight-reducing wall with an outwardly convex arc shape, one end of which is connected to one of the second sidewalls; the X direction is the length direction of the bare cell receiving cavity, and the Y direction is the width direction of the bare cell receiving cavity.

[0007] As one feasible technical solution for the aforementioned battery cell casing, the first sidewall includes two weight-reducing walls, one end of which is connected to the other end of which is connected to the two second sidewalls in a corresponding manner.

[0008] As one feasible technical solution for the aforementioned battery cell casing, the first sidewall includes a first connecting wall and two weight-reducing walls, and the outer wall of the first sidewall is a plane.

[0009] One end of the first connecting wall is connected to one of the second side walls via a weight-reducing wall, and the other end is connected to another second side wall via another weight-reducing wall.

[0010] As one feasible technical solution for the aforementioned battery cell casing, the weight-reducing wall is an arc structure with a central angle of 90°.

[0011] To achieve the above objectives, the present invention also provides a battery cell housing, including the battery cell housing provided in any of the above-described possible embodiments.

[0012] As one feasible technical solution for the above-mentioned battery cell casing, the battery cell casing has an opening at one end of the bare battery cell receiving cavity in the height direction, and the battery cell casing also includes a cover, which is connected to the battery cell casing to seal the opening;

[0013] The projection of the cover body in the first preset plane is the first projection, and the projection of the battery cell housing in the first preset plane is the second projection. The outer contour shape of the first projection and the outer contour shape of the second projection are the same. The first preset plane is parallel to the X direction and parallel to the Y direction.

[0014] To achieve the above objectives, the present invention also provides a battery cell, including the cell housing provided in any of the above-described embodiments, or including the cell outer shell provided in any of the above-described embodiments.

[0015] As one feasible technical solution for the above-mentioned battery cell, the battery cell further includes a bare cell disposed in the bare cell receiving cavity. The outer wall of the bare cell includes two outer wall surfaces arranged opposite to each other along the X direction. The outer wall surfaces are semi-circular arc surfaces, and the weight-reducing wall in contact with the outer wall surfaces is an arc structure with the same central axis as the outer wall surfaces.

[0016] To achieve the above objectives, the present invention also provides a battery pack, including a cell housing provided in any of the above-described embodiments, or a cell outer shell provided in any of the above-described embodiments, or a battery cell provided in any of the above-described embodiments.

[0017] As one feasible technical solution for the aforementioned battery pack, the battery pack further includes a side liquid cooling plate. At least one side of the side liquid cooling plate in the thickness direction is provided with a cell group. The cell group includes at least one battery cell. The side liquid cooling plate is provided with a liquid cooling groove corresponding one-to-one with the battery cells in the adjacent cell group. At least a portion of the battery cell is placed in the liquid cooling groove. The weight reduction wall placed in the liquid cooling groove is at least partially attached to the inner wall of the liquid cooling groove.

[0018] As one feasible technical solution for the aforementioned battery pack, the outer wall of the battery cell placed in the liquid cooling tank is in contact with the inner wall of the liquid cooling tank.

[0019] As one feasible technical solution for the aforementioned battery pack, the battery cell group is provided on both sides of the side liquid cooling plate in the thickness direction, and the liquid cooling grooves on both sides of the side liquid cooling plate in the thickness direction are alternately staggered along a preset direction, which is the X direction or the Y direction.

[0020] To achieve the above objectives, the present invention also provides a vehicle comprising a cell housing provided in any of the above-described embodiments, or a cell outer shell provided in any of the above-described embodiments, or a battery cell provided in any of the above-described embodiments, or a battery pack provided in any of the above-described embodiments.

[0021] The beneficial effects of this utility model are:

[0022] The battery cell housing provided by this utility model includes at least one first sidewall comprising an arc-shaped weight-reducing wall, and one end of the weight-reducing wall is connected to one of the second sidewalls. The weight-reducing wall is configured as an outwardly convex arc-shaped structure, which can reduce the space occupied by the corner edge of the battery cell housing, thereby reducing the volume of the battery cell housing and also helping to reduce the weight of the battery cell housing.

[0023] The battery cell housing provided by this utility model includes the aforementioned battery cell housing, which reduces the volume and weight of the battery cell housing by reducing its size and weight.

[0024] The battery cell provided by this utility model includes the aforementioned cell housing or cell outer shell. By reducing the volume and weight of the cell housing, the weight and volume of the battery cell are reduced, thereby increasing the volumetric energy density and gravimetric energy density of the battery cell.

[0025] The battery pack provided by this utility model includes the above-mentioned cell housing or cell shell or battery cell, and reduces the space occupied and weight of the battery pack by reducing the volume and weight of the cell housing.

[0026] The vehicle provided by this utility model includes the above-mentioned cell housing or cell shell or battery cell or battery pack, which can reduce the space occupied by the battery pack in the vehicle. Attached Figure Description

[0027] Figure 1 It is a cross-sectional view of a battery cell using a single bare cell in the prior art;

[0028] Figure 2 This is a cross-sectional view of a battery cell using a single bare cell provided in an embodiment of this utility model;

[0029] Figure 3 This is the first schematic diagram of the distribution of battery cells and side liquid cooling plates in the existing technology;

[0030] Figure 4 This is a schematic diagram of the first distribution of the battery cell and the side liquid cooling plate provided in this embodiment of the utility model;

[0031] Figure 5 This is a schematic diagram of the second distribution of battery cells and side liquid cooling plates in the prior art;

[0032] Figure 6 This is a schematic diagram of a second distribution of the battery cell and the side liquid cooling plate provided in an embodiment of the present invention;

[0033] Figure 7 This is a cross-sectional view of a battery cell using two bare cells in the existing technology;

[0034] Figure 8 This is a cross-sectional view of a battery cell using two bare cells provided in an embodiment of this utility model.

[0035] In the picture:

[0036] 1' Battery cell; 11' Cell casing; 12' Bare cell; 2' Side liquid cooling plate;

[0037] 1. Battery cell; 11. Cell casing; 111. First sidewall; 1111. Weight reduction wall; 1112. First connecting wall; 112. Second sidewall; 12. Bare cell;

[0038] 2. Side liquid cooling plate; 21. Liquid cooling tank;

[0039] 100. Battery cell assembly. Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0041] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0044] Example 1

[0045] The embodiments provided by this utility model provide a cell housing, a cell outer shell including the cell housing, a battery pack including the cell housing or a battery cell, and a vehicle including the cell housing or a battery cell or a battery pack, so as to reduce the space occupied by the battery cell and the weight of the battery cell, and reduce the cost of the battery cell.

[0046] like Figure 1 As shown, the existing cell housing 11' has a bare cell receiving cavity for accommodating the bare cell 12'. The cross-section of the bare cell receiving cavity in the direction perpendicular to its height is a rectangular ring, and the cross-section of the bare cell 12' in the direction of its height is waist-shaped. This makes it impossible for the inner wall of the bare cell receiving cavity at the corner to contact the bare cell 12', resulting in this part of the space being unusable. Moreover, this will also increase the weight of the cell housing 11'.

[0047] Therefore, embodiments of this utility model improve the structure of the battery cell housing 11, specifically, as follows: Figure 2 As shown, the battery cell housing 11 is provided with a bare battery cell receiving cavity. The battery cell housing 11 includes two first sidewalls 111 arranged opposite each other along the X direction and two second sidewalls 112 arranged opposite each other along the Y direction. At least one first sidewall 111 includes a weight-reducing wall 1111 with an outwardly convex arc shape. One end of the weight-reducing wall 1111 is connected to one of the second sidewalls 112. The X direction is the length direction of the bare battery cell receiving cavity, and the Y direction is the width direction of the bare battery cell receiving cavity.

[0048] At least one first sidewall 111 includes an arc-shaped weight-reducing wall 1111, and one end of the weight-reducing wall 1111 is connected to one of the second sidewalls 112. The weight-reducing wall 1111 is configured as an outwardly convex arc-shaped structure, which can reduce the space occupied by the corner edge of the cell housing 11 and also helps to reduce the weight of the cell housing 11.

[0049] In some embodiments, such as Figure 2 As shown, the first sidewall 111 includes two weight-reducing walls 1111, one end of the two weight-reducing walls 1111 is connected, and the other end of the two weight-reducing walls 1111 is connected to two second sidewalls 112 in a one-to-one correspondence.

[0050] For example, each of the first sidewalls 111 includes two weight-reducing walls 1111. One end of the second sidewall 112 along the X direction is connected to another second sidewall 112 through the two weight-reducing walls 1111, so that the space occupied by the two ends of the second sidewall 112 along the X direction is reduced, thereby reducing the weight of the cell housing 11 compared to using a rectangular cell housing 11.

[0051] In some embodiments, such as Figure 2 As shown, the inner wall of the bare cell housing includes arcuate surfaces corresponding to the weight-reducing walls 1111. In other words, each end of the second sidewall 112 along the X direction is connected to the other second sidewall 112 through two weight-reducing walls 1111. This helps to further reduce the weight and volume of the cell housing 11.

[0052] As an alternative, depending on actual needs, only one end of the length direction of the two second sidewalls 112 can be connected by two weight-reducing walls 1111, and the other end of the length direction of the two second sidewalls 112 can be connected to the first sidewall 111 perpendicular to the second sidewalls 112.

[0053] In some embodiments, such as Figure 2 As shown, the weight-reducing wall 1111 is an arc structure with a central angle of 90°. Two weight-reducing walls 1111 are directly connected to form a semi-circular structure, making the cross-section of the cell housing 11 in the direction perpendicular to the height of the bare cell cavity waist-shaped. This design can minimize the space occupied by the corner edges of the cell housing 11 and the weight of the cell housing 11.

[0054] The battery cell housing provided in this embodiment includes the battery cell housing 11 described above. By using the battery cell housing 11, the volume and weight of the battery cell housing can be reduced.

[0055] In some embodiments, the battery cell housing has an opening at one end in the height direction of the bare battery cell receiving cavity. The battery cell housing also includes a cover, which is connected to the battery cell housing 11 to seal the opening. The projection of the cover in a first preset plane is a first projection, and the projection of the battery cell housing 11 in the first preset plane is a second projection. The outer contour shape of the first projection and the outer contour shape of the second projection are the same. The first preset plane is parallel to the X direction and parallel to the Y direction.

[0056] The outer contour shape of the first projection is the same as that of the second projection. Compared with the existing rectangular cover, the weight and volume of the cover can be reduced, thereby reducing the weight and volume of the cell casing and reducing the volumetric energy density and gravimetric energy density of the battery cell 1.

[0057] In some embodiments, the battery cell housing 11 is an integrally molded structural component, which is low in cost and easy to mold.

[0058] The battery cell 1 provided in this embodiment includes the aforementioned cell housing 11 or the aforementioned cell outer shell. By reducing the volume and weight of the cell housing 11, the weight and volume of the battery cell 1 are reduced, thereby increasing the volumetric energy density and gravimetric energy density of the battery cell 1.

[0059] In some embodiments, the battery cell 1 further includes a bare cell 12 disposed within a bare cell housing cavity. The outer wall of the bare cell 12 includes two outer wall surfaces arranged opposite each other along the Y direction. The outer wall surfaces are semi-circular arc surfaces, and the weight-reducing wall 1111 in contact with the outer wall surfaces is an arc structure with the same central axis as the outer wall surfaces. This arrangement helps to reduce the length dimension of the cell housing 11 and reduce the weight of the cell housing 11. It should be noted that the X direction is also the length direction of the bare cell 12, and the Y direction is the width direction of the bare cell 12.

[0060] For example, both outer walls of the bare cell 12 are semi-circular arc surfaces, and the weight-reducing wall 1111 in contact with the outer wall surface is an arc structure with the same central axis as the outer wall surface, so as to minimize the length dimension of the cell housing 11 and reduce the weight of the cell housing 11.

[0061] The following example illustrates how the weight reduction of the battery cell casing is achieved before and after the improvement, using the example that the weight reduction wall 1111 is an arc structure with a central angle of 90° and each first side wall 111 includes two weight reduction walls 1111, and the battery cell casing 11 is provided with a single bare battery cell receiving cavity.

[0062] like Figure 1 and Figure 2 As shown, after the improvement, the length of the battery cell housing 11 along the X direction is W1, the radius of the arc structure is W2, and the length of the battery cell housing 11 along the Y direction is T1, where T1 = 2 × W2.

[0063] Figure 1 The cross-sectional area of ​​the bottom plate of the original battery cell casing 11, away from its opening, is M1. Figure 2 The cross-sectional area of ​​the bottom plate of the improved cell housing 11 away from its opening is M2, and M3 represents the difference between M1 and M2.

[0064] M1 = W1 × T1;

[0065] M2=(W1-2×W2)×T1+π×W22;

[0066] M3=M1-M2=T12-π×(T1 / 2)2.

[0067] Figure 1 The surface area of ​​the original battery cell housing 11 is S1=L1×H+2×S, L1=2×T+4×W2; Figure 2 The surface area of ​​the original battery cell housing 11 is S2 = L2 × H + 2 × S, where L2 = 2 × π × W2; the difference between L1 and L2 is L3, where L3 = L1 - L2 = (4 - π) × T1. Here, S represents the surface area of ​​the same portion before and after the improvement, L1 represents the sum of the lengths of the two ends of the original battery cell housing 11 in the X direction, L2 represents the sum of the lengths of the two ends of the improved battery cell housing 11 in the X direction, H represents the difference between the height of the battery cell housing 11 and the thickness of the base plate, and S3 represents the difference between S1 and S2.

[0068] Taking W1=148mm, T1=52mm, the height H of the battery cell casing 11=115mm, the thickness of the bottom plate is 1mm, the thickness of the cover is 2mm, the thickness of the second side wall 112 before the improvement is 0.5mm, and the thickness of the first side wall 111 is 0.7mm as an example.

[0069] M1=7696mm 2 M2 = 7114.654 mm 2 M3 = 581.36 mm 2 The difference in volume occupied by the battery cell casing 11 before and after the improvement is M1×H=66856.4mm. 3 The volumetric energy density of the cell casing 11 increased by 8.2% after the improvement.

[0070] Regarding the weight of the battery cell casing, the total reduction in material used for the cover is M3×2mm=1162.72mm. 3 The lid is made of aluminum plate, with an aluminum density of 2.7 g / cm³. 3 The weight of the cover decreased by 3.14g after the improvement. The total reduction in material used for the base plate of the cell casing 11 is M3×1mm=581.36mm. 3 The weight of the base plate decreased by 1.57g after the improvement.

[0071] Taking the improved arc structure thickness of 0.7mm as an example, the total volume of the cell casing 11 corresponding to the semi-circular surface of the bare cell 12 after the improvement is L2×115mm×0.7mm=13144mm. 3 Before the improvement, the cell casing 11 corresponding to the semi-circular surface of the bare cell 12 consisted of two parts: a first sidewall 111 and a portion of a second sidewall 112. The total volume at this time was 2×T1×115mm×0.7mm + 4×W2×115mm×0.5mm = 14352mm². 3 The weight of the cell casing 11, corresponding to the semi-circular arc surface of the bare cell 12, is reduced by 3.26g after the improvement. In summary, the reduction in the weight of the cell casing after the improvement is equal to 3.14g + 1.57g + 3.26g = 7.97g.

[0072] Taking the improved arc structure thickness of 0.6mm as an example, the total volume of the cell casing 11 corresponding to the semi-circular arc surface of the bare cell 12 after the improvement is L2×115mm×0.6mm=11266mm. 3 Before the improvement, the cell casing 11 corresponding to the semi-circular surface of the bare cell 12 consisted of two parts: a first sidewall 111 and a portion of a second sidewall 112. The total volume at this time was 2×T1×115mm×0.7mm + 4×W2×115mm×0.5mm = 14352mm². 3 The weight of the cell casing 11, corresponding to the semi-circular surface of the bare cell 12, is reduced by 8.33g after the improvement. In summary, the reduction in the weight of the cell casing after the improvement is equal to 3.14g + 1.57g + 8.33g = 13.04g.

[0073] Taking the improved arc structure thickness of 0.5mm as an example, the total volume of the cell casing 11 corresponding to the semi-circular surface of the bare cell 12 after the improvement is L2×115mm×0.5mm=9388.6mm. 3 Before the improvement, the cell casing 11 corresponding to the semi-circular surface of the bare cell 12 consisted of two parts: a first sidewall 111 and a portion of a second sidewall 112. The total volume at this time was 2×T1×115mm×0.7mm + 4×W2×115mm×0.5mm = 14352mm². 3 The weight of the cell casing 11, corresponding to the semi-circular arc surface of the bare cell 12, is reduced by 13.4g after the improvement. In summary, the reduction in the weight of the cell casing after the improvement is equal to 3.14g + 1.57g + 13.4g = 18.11g.

[0074] In summary, taking a 52mm×128mm×115mm cell casing as an example, the weight of the cell casing can be reduced by 7.97g-18.11g. Correspondingly, under the premise that the weight of the bare cell 12 remains unchanged, the weight of the battery cell 1 is reduced by 7.97g~18.11g. The specific weight reduction ratio is determined in conjunction with the actual thickness of the first sidewall 111 in the improved cell casing molding process.

[0075] In this invention, the battery cell housing 11 is designed to have the same shape as the bare battery cell 12, that is, a combination of a rectangular shape in the middle and semi-circular shapes at both ends. The bare battery cell 12 and the battery cell housing 11 have the same shape matching in the middle area and the areas at both ends in the X direction. The space in the corner area of ​​the battery cell housing 11 is significantly reduced, and the volume and weight of the battery cell housing 11 can be significantly reduced.

[0076] The battery pack provided in this embodiment includes the aforementioned cell housing 11, or the aforementioned cell outer shell, or the aforementioned individual battery cell 1. By reducing the volume and weight of the cell housing 11, the space occupied and weight of the battery pack are reduced.

[0077] In some embodiments, such as Figure 4 and Figure 6 As shown, the battery pack also includes a side liquid cooling plate 2. At least one side of the side liquid cooling plate 2 in the thickness direction is provided with a cell assembly 100, and the cell assembly 100 includes at least one battery cell 1. The side liquid cooling plate 2 is provided with a liquid cooling groove 21 corresponding one-to-one with the battery cell 1 in the adjacent cell assembly 100. The battery cell 1 is at least partially placed in the liquid cooling groove 21, and the weight reduction wall 1111 placed in the liquid cooling groove 21 is at least partially attached to the inner wall of the liquid cooling groove 21.

[0078] By placing the weight-reducing wall 1111, which is located in the liquid cooling tank 21, in close contact with the inner wall of the liquid cooling tank 21, it is beneficial to increase the contact area between the battery cell 1 and the side liquid cooling plate 2, thereby improving the heat dissipation efficiency of the battery cell 1. The arrangement of the liquid cooling tank 21 also reduces the size of the battery pack along the thickness direction of the side liquid cooling plate 2.

[0079] In some embodiments, the outer wall of the battery cell 1 placed in the liquid cooling tank 21 is in contact with the inner wall of the liquid cooling tank 21.

[0080] Taking battery cell 1, which includes a bare cell 12, as an example, Figure 4 In the illustrated embodiment, one end of the battery cell 1 in the X direction is placed inside the liquid cooling tank 21, and the outer wall of the battery cell 1 placed inside the liquid cooling tank 21 is in contact with the inner wall of the liquid cooling tank 21. In other words, both weight-reducing walls 1111 at one end of the battery cell 1 in the X direction are partially placed inside the liquid cooling tank 21. Compared to Figure 3 As shown, the side liquid cooling plate 2, which is in the shape of a flat plate, has a large contact area between the battery cell 1 and the side liquid cooling plate 2, resulting in high heat dissipation efficiency of the battery cell 1.

[0081] like Figure 6 In the illustrated embodiment, one end of the battery cell 1 in the Y direction is placed inside the liquid cooling tank 21, and the outer wall of the battery cell 1 placed inside the liquid cooling tank 21 is in contact with the inner wall of the liquid cooling tank 21. In other words, portions of the two weight-reducing walls 1111 at one end of the battery cell 1 in the X direction, as well as all of the first connecting walls 1112, are placed inside the liquid cooling tank 21. Compared to Figure 5 As shown, the side liquid cooling plate 2, which is in the shape of a flat plate, has a large contact area between the battery cell 1 and the side liquid cooling plate 2, resulting in high heat dissipation efficiency of the battery cell 1.

[0082] In some embodiments, cell groups 100 are provided on both sides of the side liquid cooling plate 2 in the thickness direction, and the liquid cooling grooves 21 on both sides of the side liquid cooling plate 2 in the thickness direction are alternately staggered along a preset direction, which is the X direction or the Y direction. With this arrangement, the battery cells 1 in the two cell groups 100 can be cooled by the same side wall liquid cooling plate; moreover, the liquid cooling grooves 21 on both sides of the side liquid cooling plate 2 in the thickness direction are alternately staggered along the preset direction. In other words, the liquid cooling grooves 21 on both sides of the side liquid cooling plate 2 in the thickness direction are combined and arranged in a staggered manner along the preset direction, so that the interval between the two cell groups 100 located on both sides of the side liquid cooling plate 2 and adjacent to the side liquid cooling plate 2 in the thickness direction of the side liquid cooling plate 2 is reduced, thereby reducing the size of the battery pack along the preset direction.

[0083] Taking the preset direction as the Y direction as an example, Figure 3 In the prior art shown, the side liquid cooling plate 2' is a flat plate structure. Along the thickness direction of the side liquid cooling plate 2', the maximum spacing between the two rows of cells is Y1, where Y1 = 2W1 + D11, and D11 represents the thickness of the side liquid cooling plate 2'. Figure 4 In the embodiment of this utility model shown, along the thickness direction of the side liquid cooling plate 2, the maximum spacing between two adjacent rows of battery cell groups 100 is Y2, where Y2 = 2W1 + D12, and D12 represents the minimum spacing between two adjacent rows of battery cell groups 100 along the thickness direction of the side liquid cooling plate 2. The liquid cooling grooves 21 on both sides of the side liquid cooling plate 2 are alternately staggered along a preset direction, such that D11 > D12, thereby making Y1 > Y2. Therefore, by using the liquid cooling plate with the liquid cooling grooves 21 described above, the size of the battery pack along the thickness direction of the side liquid cooling plate 2 (i.e., the X direction) can be reduced, thereby reducing the space occupied by the battery pack and increasing the volumetric energy density of the battery pack.

[0084] As an alternative, the preset direction can also be the X direction. Figure 5 In the prior art shown, along the X direction, the maximum distance between two adjacent battery cells 1' in the same cell group is Y1, Y1 = 2W1 + D21, where D21 represents the minimum distance between two adjacent battery cells 1' in the same cell group along the X direction. Figure 6 In the embodiment of this utility model shown, along the X direction, the maximum distance between two adjacent battery cells 1 in the same cell group 100 is Y2, where Y2 = 2W1 + D22, and D22 represents the minimum distance between two adjacent battery cells 1 in the same cell group 100 along the X direction. The liquid cooling grooves 21 on both sides of the side liquid cooling plate 2 in the thickness direction are alternately staggered along a preset direction, such that D21 > D22, thereby making Y1 > Y2. Therefore, by using the liquid cooling plate with the liquid cooling grooves 21 described above, the size of the battery pack along the X direction can be reduced, thereby reducing the space occupied by the battery pack and increasing the volumetric energy density of the battery pack. It should be noted that D22 can be greater than zero, equal to zero, or less than zero, depending on the specific cooling requirements, and is not specifically limited here.

[0085] In some embodiments, the liquid cooling body includes a first plate and a second plate, both of which are corrugated plates formed by stamping. The first plate and the second plate are sealed together to form a liquid cooling channel. Cooling medium flowing within the liquid cooling channel dissipates heat from the battery cell 1. The forming method is simple and low-cost. Furthermore, it is advantageous to utilize the grooves formed on the opposing surfaces of the first and second plates during the stamping process as liquid cooling grooves 21, thereby reducing processing costs. In addition, the stamped first plate improves the structural strength of the first plate, and the stamped second plate improves the structural strength of the second plate.

[0086] In some embodiments, at least two side liquid cooling plates 2 are provided, and the cell groups 100 and the side liquid cooling plates 2 are arranged alternately along the thickness direction of the side liquid cooling plates 2. Furthermore, along the thickness direction of the side liquid cooling plates 2, all cell groups 100 are located between the two outermost side liquid cooling plates 2. This arrangement ensures that the adjacent side liquid cooling plates 2 at both ends of each battery cell 1 along the thickness direction of the side liquid cooling plates 2 are in contact, thereby improving the heat dissipation efficiency of the battery cell 1.

[0087] For a battery pack using the above-mentioned cell housing 11, cell shell, or battery cell 1, the end face of the cell housing 11 away from the cover is the bottom face of the battery cell 1, the first side wall 111 of the cell housing 11 is the side face of the battery cell 1, and the second side wall 112 is the large face of the cell shell. The large face of the cell housing 11 is the outer wall face with the largest area in the cell shell of the square cell when the battery cell 1 is a square cell.

[0088] Taking battery cell 1, which includes a bare cell 12, as an example. Figure 3 As shown, before the improvement, the entire side of the battery cell 1 could contact the side liquid cooling plate 2. The contact area between the battery cell 1 and the side liquid cooling plate 2 is denoted as S11, where S11 = 52mm × 148mm = 7696mm. 2. Figure 4 As shown, after the improvement, the first sidewall 111 contacts the side liquid cooling plate 2, and the contact area between the first sidewall 111 and the side liquid cooling plate 2 is S12, where S12 = π × 52 mm / 2 × 115 mm = 9388.6 mm. 2 Therefore, it can be seen that increasing the contact area by 22% can significantly increase the heat exchange area between the battery cell 1 and the side liquid cooling plate 2, thereby improving the heat dissipation efficiency of the battery cell 1.

[0089] like Figure 5 As shown, before the improvement, the entire surface of the battery cell 1 is in contact with the side liquid cooling plate 2, and the contact area between the battery cell 1 and the side liquid cooling plate 2 is S21, where S21 = 148 × 115 = 17020 mm. 2 ;like Figure 6 As shown, after the improvement, the first sidewall 111 includes two arc structures with rounded corners of 90°, the liquid cooling tank 21 is a semi-circular tank, and the contact area between the large surface of the battery cell 1 and the first sidewall 111 connected to the large surface and the contact side liquid cooling plate 2 is S22, where S22 = (148 + π × 52 / 2 - 52) × 115 = 20428.6 mm. 2 Therefore, it can be seen that increasing the contact area by 20% can significantly increase the heat exchange area between the battery cell 1 and the side liquid cooling plate 2, thereby improving the heat dissipation efficiency of the battery cell.

[0090] The cell housing 11 provided by this utility model has an irregular shape design, which makes the structure of the cell housing 11 match the arc structure at both ends of the bare cell 12 in the length direction, thereby reducing the size and weight of the cell housing 11 and improving the energy density of the battery cell 1 and the assembly efficiency of the battery pack.

[0091] The battery cell housing 11 provided by this utility model includes two arc structures with rounded corners of 90° for each first sidewall 111, so that the cross-section of the battery cell housing 11 in the direction perpendicular to the height of the bare battery cell cavity is waist-shaped, that is, the two sides of the battery cell housing 11 are adapted to the arc structures at both ends of the length direction of the bare battery cell 12. This configuration can not only minimize the weight and volume of the battery cell 1, but also reduce the volumetric energy density and gravimetric energy density of the battery cell 1.

[0092] The vehicle provided in this embodiment of the utility model includes the cell housing 11 provided in any of the above embodiments, or the cell shell provided in any of the above embodiments, or the battery cell 1 provided in any of the above embodiments, or the battery pack provided in any of the above embodiments, which can reduce the space occupied by the battery pack in the vehicle.

[0093] Example 2

[0094] The difference between this embodiment and Embodiment 1 is that, as Figure 8As shown, at least two bare cells 12 are arranged along the Y direction within the bare cell housing cavity, with adjacent bare cells 12 abutting each other along the Y direction. Exemplarily, two bare cells 12 are provided within the cell housing 11; the two bare cells 12 can be connected in series or in parallel, and this is not specifically limited here. Alternatively, three or more bare cells 12 can also be provided within the cell housing 11.

[0095] In some embodiments, the first sidewall 111 includes a first connecting wall 1112 and two weight-reducing walls 1111. The first connecting wall 1112 is a flat plate structure. One end of the first connecting wall 1112 is connected to one of the second sidewalls 112 through a weight-reducing wall 1111, and the other end is connected to another second sidewall 112 through another weight-reducing wall 1111.

[0096] The two weight-reducing walls 1111 of the same first sidewall 111 are connected by a first connecting wall 1112. The first connecting wall 1112 is a flat plate structure, which can reduce the space occupied by the second sidewall 112 at both ends along the X direction while allowing at least two bare cells 12 to be installed in the cell housing 11. Compared with using Figure 7 The rectangular cell housing 11' shown reduces the weight of the cell housing 11.

[0097] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery cell casing, characterized in that, The battery cell housing (11) is provided with a bare battery cell receiving cavity. The battery cell housing (11) includes two first sidewalls (111) arranged opposite each other in the X direction and two second sidewalls (112) arranged opposite each other in the Y direction. At least one of the first sidewalls (111) includes a weight-reducing wall (1111) in the shape of an outwardly convex arc, one end of which is connected to one of the second sidewalls (112); the X direction is the length direction of the bare cell receiving cavity, and the Y direction is the width direction of the bare cell receiving cavity.

2. The cell housing according to claim 1, characterized in that, The first sidewall (111) includes two weight-reducing walls (1111), one end of the two weight-reducing walls (1111) is connected, and the other end of the two weight-reducing walls (1111) is connected to the two second sidewalls (112) in a one-to-one correspondence.

3. The cell housing according to claim 1, characterized in that, The first sidewall (111) includes a first connecting wall (1112) and two weight-reducing walls (1111), and the first sidewall (111) is a flat plate structure; One end of the first connecting wall (1112) is connected to one of the second side walls (112) through a weight-reducing wall (1111), and the other end is connected to another second side wall (112) through another weight-reducing wall (1111).

4. The cell housing according to any one of claims 1 to 3, characterized in that, The weight-reducing wall (1111) is a circular arc structure with a central angle of 90°.

5. The battery cell casing, characterized in that, Includes the cell housing (11) as described in any one of claims 1 to 4.

6. The battery cell casing according to claim 5, characterized in that, The battery cell housing has an opening at one end of the bare battery cell receiving cavity in the height direction, and the battery cell housing also includes a cover, which is connected to the battery cell housing (11) to seal the opening; The projection of the cover body in the first preset plane is the first projection, and the projection of the battery cell housing (11) in the first preset plane is the second projection. The outer contour shape of the first projection and the outer contour shape of the second projection are the same. The first preset plane is parallel to the X direction and parallel to the Y direction.

7. A single battery cell, characterized in that, It includes the cell housing (11) as described in any one of claims 1 to 4, or the cell outer casing as described in claim 5 or 6.

8. The battery cell according to claim 7, characterized in that, The battery cell (1) also includes a bare cell (12) disposed in the bare cell receiving cavity. The outer wall of the bare cell (12) includes two outer wall surfaces arranged opposite to each other along the X direction. The outer wall surface is a semi-circular arc surface. The weight reduction wall (1111) in contact with the outer wall surface is an arc structure with the same central axis as the outer wall surface.

9. A battery pack, characterized in that, It includes the cell housing (11) as described in any one of claims 1 to 4, or the cell casing as described in claim 5 or 6, or the battery cell (1) as described in claim 7 or 8.

10. The battery pack according to claim 9, characterized in that, The battery pack also includes a side liquid cooling plate (2), and a cell group (100) is provided on at least one side of the side liquid cooling plate (2) in the thickness direction. The cell group (100) includes at least one battery cell (1). The side liquid cooling plate (2) is provided with a liquid cooling tank (21) corresponding one-to-one with the battery cell (1) in the adjacent cell group (100). The battery cell (1) is at least partially placed in the liquid cooling tank (21). The weight reduction wall (1111) placed in the liquid cooling tank (21) is at least partially attached to the inner wall of the liquid cooling tank (21).

11. The battery pack according to claim 10, characterized in that, The outer wall of the battery cell (1) placed in the liquid cooling tank (21) is in contact with the inner wall of the liquid cooling tank (21).

12. The battery pack according to claim 10, characterized in that, The battery cell assembly (100) is provided on both sides of the side liquid cooling plate (2) in the thickness direction. The liquid cooling tanks (21) on both sides of the side liquid cooling plate (2) in the thickness direction are alternately staggered along a preset direction, which is the X direction or the Y direction.

13. A vehicle, characterized in that, It includes the cell housing (11) as described in any one of claims 1 to 4, or the cell casing as described in claim 5 or 6, or the battery cell (1) as described in claim 7 or 8, or the battery pack as described in any one of claims 9 to 12.

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