Battery assembly, battery pack, and power utilization system

Abstract

The application provides a battery assembly, a battery pack and a power utilization system. The battery assembly comprises a plurality of battery cells stacked in a vertical direction, any surface of the battery cells between two adjacent battery cells is a first surface, and the first surface is provided with a support and an adhesive. The support, the adhesive and the first surface cooperatively form an avoiding area, and the area ratio of the avoiding area to the first surface is between 3:20 and 18:25. The battery assembly of the application sets the support and the adhesive between the two adjacent battery cells to cooperatively form the avoiding area with the first surface, so as to avoid the separation of the two stacked battery cells, and at the same time, a gap is formed between the opposite surfaces of the two adjacent battery cells to provide a reserved expansion space. The area ratio of the avoiding area to any surface of the battery cells is between 3:20 and 18:25, so as to ensure the reliability of the reserved expansion space, thereby coping with the expansion of the battery cells after multiple charging and discharging cycles, and improving the performance and service life of the battery assembly.

Description

Technical Field

[0001] This application relates to the field of power battery technology, and in particular to a battery component, battery pack and power system. Background Technology

[0002] Battery modules can be composed of multiple cells stacked vertically, with these cells connected in series or parallel to provide all or most of the power to the vehicle. As a key component of electric vehicles, the performance and lifespan of the battery module are of paramount importance.

[0003] In existing technologies, stacked battery cells are typically secured by cable ties around the perimeter to ensure the stability of the battery assembly. However, after prolonged charge-discharge cycles, each cell expands to some extent. The cumulative expansion force from multiple cells is significant, which can cause the cable ties to break, leading to cell detachment and affecting the battery assembly's performance and lifespan. Alternatively, the cells may squeeze against each other, resulting in lithium plating, which also negatively impacts the battery assembly's performance and lifespan. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a battery component and a vehicle, so as to provide a certain reserved expansion space, thereby improving the performance and service life of the battery component.

[0005] In a first aspect, this application provides a battery assembly including a plurality of cells stacked in a vertical direction, wherein the surface of one of the cells between two adjacent cells is a first surface, and the first surface is provided with a support member and an adhesive member; a clearance area is provided on the first surface, the geometric center of the first surface is located within the clearance area, and the edges of the support member and the adhesive member near the geometric center of the first surface coincide with a portion of the edge of the clearance area;

[0006] The extension lines of the edges of each support and each adhesive member near the geometric center of the first surface have a first intersection point where they intersect each other, and / or the extension lines of the edges of each support and each adhesive member near the geometric center of the first surface have a second intersection point where they intersect each other with the edge of the first surface.

[0007] If all intersections are second intersections, the avoidance zone is the area formed by connecting and enclosing multiple second intersections;

[0008] If the intersection includes several first intersections and several second intersections, and the first intersections are connected in sequence to form a closed shape on the first surface, the avoidance area is the area formed by connecting multiple first intersections and enclosing them.

[0009] If the intersection includes several first intersections and several second intersections, and the first intersections cannot be connected in sequence to form a closed shape on the first surface, the avoidance area is the area formed by connecting all the first intersections and several second intersections in sequence.

[0010] The ratio of the area of ​​the avoidance zone to the area of ​​the first surface is between 3:20 and 18:25.

[0011] The battery assembly of this application provides electrical energy by arranging multiple cells stacked vertically. Support members are placed between adjacent cells to support them. Furthermore, adhesive members are placed between adjacent cells to limit their relative displacement and prevent separation.

[0012] Understandably, the battery assembly of this application forms a clearance zone on the first surface by providing support members and adhesive members that cooperate with the first surface to ensure relative fixation between adjacent cells and prevent detachment between stacked adjacent cells. Simultaneously, a gap is formed on the opposing surfaces of adjacent cells to provide a certain amount of reserved expansion space, preventing adjacent cells from squeezing each other due to excessive expansion force. Furthermore, the ratio of the area of ​​the clearance zone to the area of ​​one of the cell surfaces is between 3:20 and 18:25 to ensure the reliability of the reserved expansion space, thereby coping with the expansion of the cells after multiple charge-discharge cycles, improving the performance and lifespan of the battery assembly.

[0013] In one embodiment, the ratio of the area of ​​the avoidance zone to the area of ​​the first surface is between 1:5 and 11:20.

[0014] In one embodiment, each cell includes a first sidewall located on the same side of the battery assembly, the first sidewall being perpendicular to a first surface, the cell including a terminal post disposed on the first sidewall, and a support including a first support disposed close to the first sidewall.

[0015] In this embodiment, a terminal post is provided on the first sidewall of the battery cell perpendicular to the first surface, serving as a power lead-out end. Simultaneously, considering that the side of the battery cell with the terminal post has a relatively larger weight, a first support member is provided near the first sidewall to ensure that the formed reserved expansion space is relatively reliable.

[0016] In one embodiment, there are two terminals, which are spaced apart along the length of the battery assembly; there is one support member, and the two ends of the first support member are equidistant from the two terminals along the length of the battery assembly.

[0017] In this embodiment, based on the vertical direction, the poles on the same side of two adjacent cells, that is, poles of the same polarity, are connected by a connecting piece, and the two poles of the cell are respectively located at opposite ends of the first sidewall along the length direction of the battery assembly. By setting the distance from the two ends of the first support member along the length direction of the battery assembly to the two poles to be equal, that is, setting the support member at the middle position of the cell along the length direction of the battery assembly, it is to prevent the connecting piece from being twisted due to local compression of the cell.

[0018] In one embodiment, there are two adhesive members, and the two adhesive members are arranged at intervals along the length of the battery assembly. The extension line of the edge of each adhesive member near the geometric center of the first surface has an angle with the extension line of the edge of the first support member near the geometric center of the first surface, and the angle is in the range of 60° to 100°.

[0019] In this embodiment, two adhesive members are spaced apart along the length of the battery assembly. The angle between the extended line of the edge of the adhesive member near the geometric center of the first surface and the extended line of the edge of the first support member near the geometric center of the first surface is between 60° and 100°. This ensures that the adhesive members reliably bond the opposing surfaces between two adjacent battery cells, thereby ensuring the overall bonding reliability between the two adjacent battery cells.

[0020] In one embodiment, along the width direction of the battery assembly, the first support member is provided on the side of the avoidance area near the first sidewall, and along the length direction of the battery assembly, the adhesive members are respectively provided on opposite sides of the avoidance area along the length direction of the battery assembly, and the two adhesive members are respectively in contact with the first support member.

[0021] In this embodiment, a first support member is provided on the side of the clearance area near the first sidewall along the width direction of the battery assembly, and adhesive members are provided on opposite sides of the clearance area along the length direction of the battery assembly, so that the two adhesive members are in contact with the first support member, thereby increasing the reliability of the reserved expansion space provided by the clearance area.

[0022] In one embodiment, the projections of the first support member and the adhesive member on the first surface are both rectangles, and the first support member and the adhesive member are perpendicular to each other.

[0023] In this embodiment, by setting the projections of the first support member and the adhesive member on the first surface to be rectangular, and setting the first support member and the adhesive member to be perpendicular to each other, the shape of the avoidance area is made relatively regular, which optimizes the layout of the support member and the adhesive member and improves the reliability of the avoidance area.

[0024] In one embodiment, along the width direction of the battery assembly, the battery assembly has a second sidewall opposite to the first sidewall, the second sidewall being connected to and perpendicular to the first surface;

[0025] The extension line of the edge of the support member near the geometric center of the first surface intersects with the extension lines of the edges of the two adhesive members near the geometric center of the first surface, forming two first intersection points. The extension lines of the edges of the two adhesive members near the geometric center of the first surface intersect with the edges connected to the second sidewall, forming two second intersection points. The avoidance area is the area formed on the first surface by connecting the two first intersection points and the two second intersection points.

[0026] In one embodiment, the ratio of the sum of the projected areas of the support members on the cell surface to the area of ​​the cell surface is between 0.1% and 10%.

[0027] In this embodiment, the ratio of the sum of the projected areas of the support members on the surface of the battery cell to the area of ​​the battery cell surface is set between 0.1% and 10% to ensure the support effect of the support members and the reliability of the reserved expansion space.

[0028] In one embodiment, the ratio of the sum of the projected areas of the adhesives on the cell surface to the area of ​​the cell surface is between 20% and 70%.

[0029] In this embodiment, the ratio of the sum of the projected areas of the adhesive components on the surface of the battery cell to the area of ​​the battery cell surface is set between 20% and 70% to ensure the bonding effect of the adhesive components and the reliability of the reserved expansion space.

[0030] In one embodiment, the ratio of the sum of the projected areas of the support members on the surface of the battery cell to the area of ​​the battery cell surface is between 0.1% and 10%; the ratio of the sum of the projected areas of the adhesive members on the surface of the battery cell to the area of ​​the battery cell surface is between 20% and 70%.

[0031] In this embodiment, by setting the ratio of the sum of the projected areas of the support members on the cell surface to the area of ​​the cell surface between 0.1% and 10%, and simultaneously setting the ratio of the sum of the projected areas of the adhesive members on the cell surface to the area of ​​the cell surface between 20% and 70%, on the one hand, the sum of the projected areas of the adhesive members on the cell surface is greater than the sum of the projected areas of the support members on the cell surface. This ensures that the adhesive force of the adhesive members on the cell is greater than the supporting force of the support members on the cell, thus ensuring the stability of the stacking between adjacent cells and preventing them from detaching. On the other hand, it avoids the adhesive members occupying too large an area on the cell surface, resulting in insufficient reserved expansion space, which would affect heat dissipation and increase costs.

[0032] In one embodiment, the height of the support member is greater than or equal to the height of the adhesive member in the vertical direction.

[0033] In this embodiment, by setting the height of the support member to be slightly greater than or equal to the height of the adhesive member, a sufficiently large reserved expansion space is provided in the early stage of the cell's life cycle to prevent the cell from being squeezed in the early stage of its life cycle and affecting the cell's service life.

[0034] In one embodiment, the number of supports is one, and the ratio of the length of the support to the length of the first sidewall is between 2:5 and 7:10 along the length direction of the battery assembly.

[0035] In this embodiment, the ratio of the length of the support member to the length of the first sidewall is set between 2:5 and 7:10 along the length direction of the battery assembly to ensure the support effect of the support member and reduce costs.

[0036] In one embodiment, the ratio of the distance from the geometric center of the support to the first sidewall to the distance to the geometric center of the cell surface is between 0 and 4:5.

[0037] In this embodiment, by keeping the ratio of the distance from the geometric center of the support member to the first sidewall to the distance to the geometric center of the cell surface between 0 and 4:5, the position of the support member is relatively far away from the geometric center of the cell surface, thereby ensuring that sufficient reserved expansion space is provided in the central region of the cell surface.

[0038] In one embodiment, along the length of the first sidewall, the ratio of the distance from the geometric center of the adhesive to its relatively adjacent sidewall to the distance to the geometric center of the cell surface is between 0 and 17:20.

[0039] In this embodiment, by setting the ratio of the distance from the geometric center of the adhesive to its relatively close sidewall to the distance to the geometric center of the cell surface to be between 0 and 17:20, the relative position of the adhesive is ensured to be far away from the geometric center of the cell surface, thereby ensuring that sufficient reserved expansion space is provided in the central area of ​​the cell surface.

[0040] In one embodiment, the battery assembly further includes a filler adhesive disposed between two adjacent cells. The cells include a second sidewall disposed opposite to the first sidewall, and the filler adhesive is disposed close to the second sidewall.

[0041] In this embodiment, by placing a filler adhesive between two adjacent battery cells and positioning it close to the second sidewall opposite to the first sidewall, the filler adhesive and the support member work together to support the stacked adjacent battery cells, enhancing the stability of the support. Simultaneously, due to the adhesive's adhesive properties, it can also assist the adhesive member in limiting the relative displacement between two adjacent battery cells.

[0042] In one embodiment, the ratio of the area formed by the support, adhesive, and filler on the surface of the cell to the area of ​​the cell surface is between 1:5 and 11:20.

[0043] In this embodiment, since the support, adhesive, and filler are all strip-shaped, the ratio of the area formed by the support, adhesive, and filler on the surface of the cell to the area of ​​the cell surface is set between 1:5 and 11:20, so as to provide sufficient reserved expansion space while further improving the adhesion between adjacent cells.

[0044] Secondly, this application provides a battery pack including the battery assembly as described in any of the above embodiments.

[0045] Thirdly, this application provides an electrical system including a battery assembly as described in any of the above embodiments or including a battery pack as described above. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram of the vehicle structure provided in one embodiment of this application;

[0048] Figure 2 This is a schematic diagram of the planar structure of one side of the battery assembly provided in one embodiment of this application;

[0049] Figure 3 This is a schematic diagram of the planar structure of the battery assembly on the other side of one embodiment of this application;

[0050] Figure 4 This is a schematic diagram of the planar structure of one side of the battery assembly provided in another embodiment of this application;

[0051] Figure 5 This is a schematic diagram of the planar structure of one side of the battery assembly provided in another embodiment of this application;

[0052] Figure 6 This is a schematic diagram of the planar structure of one side of the battery assembly provided in another embodiment of this application;

[0053] Figure 7 This is a schematic diagram of the planar structure of one side of the battery assembly provided in another embodiment of this application;

[0054] Figure 8 This is a schematic diagram of the planar structure of one side of the battery assembly provided in another embodiment of this application;

[0055] Figure 9 This is a schematic diagram of the planar structure of one side of the battery assembly provided in another embodiment of this application.

[0056] Reference numerals: 200-Vehicle; 201-Body; 100-Battery Component; 10-Cell; 11-First Surface; 111-Avoidance Zone; 12-Side Wall; 12a-First Side Wall; 12b-Second Side Wall; 12c-Third Side Wall; 12d-Fourth Side Wall; 13-Terminal Post; 14-Explosion-proof Valve; 15-First Intersection Point; 16-Second Intersection Point; 20-Support Component; 20a-First Support Component; 30-Adhesive Component; 40-Filling Adhesive; 001-First Direction; 002-Second Direction; 003-Third Direction. Detailed Implementation

[0057] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0058] The following descriptions of the embodiments are based on the accompanying illustrations and are used to illustrate specific embodiments in which this application can be implemented. The component designations used herein, such as "first," "second," etc., are merely for distinguishing the described objects and do not have any sequential or technical meaning. Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages). Directional terms used in this application, such as "up," "down," "front," "rear," "left," "right," "inner," "outer," "side," etc., are merely for reference to the accompanying drawings. Therefore, the use of directional terms is for better and clearer explanation and understanding of this application, and does not indicate or imply that the referred device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this application.

[0059] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joint" 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; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. It should be noted that the terms "first," "second," etc., in the specification, claims, and drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising," "may include," "include," or "may include" used in this application indicate the presence of the corresponding disclosed function, operation, element, etc., and do not limit one or more other functions, operations, elements, etc. Moreover, the terms "comprising" or "include" indicate the presence of the corresponding features, numbers, steps, operations, elements, components, or combinations thereof disclosed in the specification, but do not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, and are intended to cover non-exclusive inclusion.

[0060] Please see Figure 2 The diagram shown is a planar structural schematic of one side of the battery assembly 100 provided in one embodiment of this application, and is shown in conjunction with... Figure 3 The diagram shows a planar structure of the other side of the battery assembly 100 provided in one embodiment of this application.

[0061] like Figure 2 and Figure 3 As shown, the battery assembly 100 of this application includes a battery cell 10, a support member 20, and an adhesive member 30. In one embodiment of this application, the battery cell 10 is a square cell, that is, the shape of the battery cell 10 is a six-sided cube. The battery cell 10 includes an upper surface and a lower surface disposed opposite to each other along a first direction 001. Wherein, the first direction 001 is the vertical direction. The number of battery cells 10 is two, and the two battery cells 10 are stacked along the first direction 001. Wherein, in order to ensure the stability of the stacked battery cells 10, the battery assembly 100 stacks the battery cells 10 using the surfaces with larger areas. Specifically, the upper surface and the lower surface of the battery cell 10 have significantly larger areas than the other sides. For ease of description, the upper surface and the lower surface of the battery cell 10 are defined as the large surface of the battery cell 10, and the large surface of any one of the battery cells 10 is the first surface 11.

[0062] In one embodiment disclosed in this application, the battery cell 10 further includes terminals 13 and an explosion-proof valve 14, both of which are disposed on one of the sidewalls 12 of the battery cell 10. Specifically, the explosion-proof valve 14 is disposed in the middle of the sidewall 12 along the length direction of the battery assembly 100, that is, in the middle of the first sidewall 12a. There are two terminals 13, and the two terminals 13 are disposed on opposite sides of the explosion-proof valve 14 along the length direction of the battery assembly 100. The distances from the two terminals 13 to the explosion-proof valve 14 are equal. The first sidewall 12a is perpendicular to the first surface 11 of the battery cell 10. The terminals 13 can serve as power output terminals to extract the electrical energy stored in the battery cell 10. The explosion-proof valve 14 can be used for pressure relief and venting to prevent the battery cell 10 from exploding due to gas expansion. In another embodiment disclosed in this application, the electrode post 13 and the explosion-proof valve 14 are respectively disposed on different side walls 12 of the battery cell 10, and the side walls 12 are connected to the upper surface and the lower surface. Among them, the side wall 12 on which the electrode post 13 is disposed is the first side wall 12a.

[0063] Furthermore, in the embodiments disclosed in this application, the opposing surfaces of two adjacent cells 10 along the stacking direction are designated as a first surface 11, on which a support member 20 and an adhesive member 30 are disposed. The battery assembly 100 of this application also includes a clearance area 111 formed on the first surface 11, with the geometric center of the first surface 11 located within the clearance area 111. The edges of the support member 20 and the adhesive member 30 near the geometric center of the first surface 11 coincide with a portion of the edge of the clearance area 111. That is, the clearance area 111 is defined by the support member 20 and the adhesive member 30. Alternatively, it can be understood that the clearance area 111 is formed by the support member 20, the adhesive member 30, and the first surface 11 working together to enclose it. In other words, the avoidance area 111 of this application is the area formed by the intersection of the extended lines of the edges of each support member 20 and each adhesive member 30 near the geometric center of the first surface 11 and / or the intersection of the extended lines of the edges of each support member 20 and each adhesive member 30 near the geometric center of the first surface 11 with the edge of the first surface 11, thereby enclosing the area on the first surface 11.

[0064] That is, if the extension lines of the edges of the support members 20 or adhesive members 30 near the geometric center of the first surface 11 intersect with other support members 20 or adhesive members 30 and can form a closed shape on the first surface 11, then the clearance area 111 is the area formed by the intersection of the extension lines of the edges of the multiple support members 20 or adhesive members 30 near the geometric center of the first surface 11 and enclosed on the first surface 11. If the extension lines of the edges of the support members 20 or adhesive members 30 near the geometric center of the first surface 11 intersect with other support members 20 or adhesive members 30 but cannot form a closed shape on the first surface 11, then the clearance area 111 is the area formed by the intersection of the extension lines of the edges of the multiple support members 20 or adhesive members 30 near the geometric center of the first surface 11 and the edge of the first surface 11 and enclosed on the first surface 11. If the extended line of the edge of the support member 20 or adhesive member 30 near the geometric center of the first surface 11 does not intersect with other support members 20 or adhesive members 30, then the clearance area 111 is the area enclosed on the first surface 11 by the intersection of the extended lines of the edges of the support member 20 and adhesive member 30 near the geometric center of the first surface 11 and the edge of the first surface 11. The ratio of the area of ​​the clearance area 111 to the area of ​​the first surface 11 is between 3:20 and 18:25. It should be noted that this area excludes the area occupied by the support member 20 and adhesive member 30 themselves on the first surface 11. For ease of understanding, this application provides the following embodiments to illustrate the clearance area 111.

[0065] exist Figure 3 In the illustrated embodiment, the projections of the support member 20 and the adhesive member 30 on the first surface 11 are both rectangular. There are three support members 20 and two adhesive members 30. The two adhesive members 30 are spaced apart along the second direction 002 on opposite sides of the geometric center of the first surface 11. Each support member 20 is positioned close to the first sidewall 12a. The extended lines of the edges of a support member 20 and an adhesive member 30 near the geometric center of the first surface 11 intersect to form a first intersection point 15. The extended lines of the edges of the two adhesive members 30 near the geometric center of the first surface 11 intersect with the edges of the first surface 11 to form second intersection points 16. The three support members 20 are interconnected and sequentially connected to the first intersection point 15 and the second intersection point 16 in a clockwise or counterclockwise direction to form a clearance area 111. That is, the clearance area 111 is... Figure 3 The area enclosed by the dashed line portion, the support member 20, the adhesive member 30, and the edge of the first surface 11.

[0066] like Figure 4As shown, in one embodiment, the projections of the support member 20 and the adhesive member 30 on the first surface 11 are both rectangles. There is one support member 20 and one adhesive member 30. The support member 20 is relatively close to the first sidewall 12a, and both the support member 20 and the adhesive member 30 extend along the second direction 002. The extension line of the edge of the support member 20 near the geometric center of the first surface 11 intersects the edge of the first surface 11 to form a second intersection point 16, and the extension line of the edge of the adhesive member 30 near the geometric center of the first surface 11 also intersects the edge of the first surface 11 to form a second intersection point 16. The second intersection points 16 are sequentially connected to form a clearance area 111. That is, the clearance area 111 is then... Figure 4 The area enclosed by the dashed line portion, the support member 20, the adhesive member 30, and the edge of the first surface 11.

[0067] like Figure 5 As shown, in one embodiment, the projections of the support member 20 and the adhesive member 30 on the first surface 11 are both rectangles. There is one support member 20 and one adhesive member 30, with the support member 20 relatively close to the first sidewall 12a. The support member 20 extends along the second direction 002, and the adhesive member 30 extends along the third direction 003. The extension line of the edge of the support member 20 near the geometric center of the first surface 11 intersects the edge of the first surface 11 to form a second intersection point 16. The extension line of the edge of the adhesive member 30 near the geometric center of the first surface 11 also intersects the edge of the first surface 11 to form a second intersection point 16. Simultaneously, the extension lines of the edges of the support member 20 and the adhesive member 30 near the geometric center of the first surface 11 also intersect to form a first intersection point. The two second intersection points 16 and the first intersection point 15 are connected sequentially to form a clearance area 111. That is, the clearance area 111 is... Figure 5 The area enclosed by the dashed line portion, the support member 20, the adhesive member 30, and the edge of the first surface 11.

[0068] like Figure 6 As shown, in one embodiment, the projections of the support members 20 and the adhesive members 30 on the first surface 11 are both irregular shapes. There are three support members 20 and three adhesive members 30. The support members 20 are relatively close to the first sidewall 12a, and are arbitrarily arranged. The adhesive members 30 are also arbitrarily arranged. The extended lines of the edges of a support member 20 and an adhesive member 30 near the geometric center of the first surface 11 intersect to form a first intersection point 15. The support members 20 are interconnected, and the adhesive members 30 are interconnected and sequentially connected to the first intersection point 15 in a clockwise or counterclockwise direction to form a clearance area 111. That is, the clearance area 111 is... Figure 6 The area enclosed by the dotted line and each support member 20 and each adhesive member 30.

[0069] like Figure 8 As shown, in one embodiment, along the width direction of the battery assembly 100, i.e., along the third direction 003, the battery assembly 100 has a second sidewall 12b opposite to the first sidewall 12a. The second sidewall 12b is connected to and perpendicular to the first surface 11. There is one support member 20 and three adhesive members 30. The extension line of the edge of the support member 20 near the geometric center of the first surface 11 intersects with the extension lines of the edges of the two adhesive members 30 near the geometric center of the first surface 11, forming two first intersection points 15. The extension lines of the edges of the two adhesive members 30 near the geometric center of the first surface 11 intersect with the edge connecting to the second sidewall 12b, forming two second intersection points 16. The clearance area 111 is the area formed on the first surface 11 by the connection of the two first intersection points 15 and the two second intersection points 16. That is, the clearance area 111 is... Figure 5 The area enclosed by the central support member 20, the adhesive member 30, and the second sidewall 12b.

[0070] It should be noted that the avoidance area 111 in the above embodiments is only an example and does not represent the actual structure of the avoidance area 111. That is, the avoidance area 111 of this application can be adaptively adjusted according to the number, shape and arrangement of the support member 20 and the adhesive member 30, as long as the ratio of the area of ​​the avoidance area 111 to the area of ​​the first surface 11 is between 3:20 and 18:25. This application will not elaborate on these details here.

[0071] Understandably, the battery assembly 100 of this application forms a clearance area 111 by providing a support member 20 and an adhesive member 30 on the first surface 11, which cooperate with the first surface 11 to ensure that two adjacent cells 10 are relatively fixed and to prevent two stacked adjacent cells 10 from detaching. At the same time, a gap is formed on the opposing surfaces of two adjacent cells 10 to provide a certain amount of reserved expansion space, preventing the two adjacent cells 10 from squeezing each other due to excessive expansion force, thus reducing the probability of lithium plating in the cells 10. Furthermore, the ratio of the area of ​​the clearance area 111 to the area of ​​one of the cell 10 surfaces is between 3:20 and 18:25 to ensure the reliability of the reserved expansion space, thereby coping with the expansion of the cells 10 after multiple charge-discharge cycles, improving the performance and service life of the battery assembly 100 of this application.

[0072] In a preferred embodiment, the ratio of the area of ​​the avoidance zone 111 to the area of ​​the first surface 11 is between 1:5 and 11:20. Because the reserved expansion space provided within this range is sufficiently large, and the support effect of the support member 20 is relatively good, the bonding effect of the adhesive member 30 is relatively stable, which can further reduce the probability of lithium plating in the cell 10 and further improve the performance and service life of the battery assembly 100.

[0073] In the above embodiment, the geometric center of the avoidance area 111 coincides with the geometric center of the first surface 11. It can be understood that, since the bulging and expansion phenomenon of the battery cell 10 usually occurs in the middle region of the battery cell 10, the geometric center of the avoidance area 111 is set to coincide with the geometric center of the first surface 11 to ensure that the provided reserved expansion space works effectively.

[0074] In one embodiment disclosed in this application, there are multiple support members 20, which are located between two adjacent battery cells 10 and are disposed on the first surface 11 close to the first sidewall 12a. Simultaneously, the distance between each support member 20 and the sidewall 12 of the battery cell 10 is less than the distance between the support member 20 and the geometric center of the first surface 11 of the battery cell 10; that is, the position of the support member 20 is further away from the geometric center of the first surface 11 of the battery cell 10 relative to the sidewall 12. The support members 20 can provide physical spatial support for two stacked adjacent battery cells 10, allowing for a certain gap between the two adjacent battery cells 10 to provide a certain amount of reserved expansion space for the battery cells 10.

[0075] It should be noted that the number and position of the support members 20 are only illustrative examples and do not represent the actual number and position of the support members 20. That is, the number and position of the support members 20 can be adaptively adjusted according to the actual application scenario, as long as at least one support member 20 is set close to the first side wall 12a.

[0076] In one embodiment disclosed in this application, there are two adhesive members 30, which are located between two adjacent battery cells 10. The two adhesive members 30 are positioned on opposite sides of the geometric center of the first surface 11 of the battery cell 10 along a second direction 002, wherein the second direction 002 is parallel to the length direction of the first sidewall 12a, i.e., the second direction 002 is the length direction of the battery assembly 100. The adhesive members 30 also extend along a third direction 003, such that the projection of the adhesive member 30 onto the first surface 11 of the battery cell 10 is rectangular. The third direction 003 is the width direction of the battery assembly 100. Simultaneously, the distance between the adhesive member 30 and the sidewall 12a of the battery cell 10 is less than the distance between the adhesive member 30 and the geometric center of the first surface 11 of the battery cell 10, i.e., the position of the adhesive member 30 is further away from the geometric center of the battery cell 10 relative to the sidewall 12a. The adhesive 30 is used to bond the first surfaces 11 of two battery cells 10 that are relatively close to each other, so as to limit the relative displacement between the two adjacent battery cells 10 and prevent the adjacent battery cells 10 from separating.

[0077] It should be noted that the shape, quantity and position of the adhesive 30 are only illustrative examples and do not represent the actual shape, quantity and position of the adhesive 30. That is, the shape, quantity and position of the adhesive 30 can be adapted to the actual application scenario, as long as the adhesive 30 can bond two adjacent cells 10.

[0078] In one embodiment disclosed in this application, since the side of the battery cell 10 with the electrode post 13 has a relatively large weight, at least one support member 20 is provided near the first sidewall 12a, that is, the first support member 20a is provided, to ensure that the reserved expansion space formed in the avoidance area 111 of the first surface 11 is relatively reliable.

[0079] In one embodiment disclosed in this application, the support member 20 may be made of polydimethylsiloxane material, so that the support member 20 has both slight elasticity and strong rigid support capacity. The adhesive member 30 may be made of polybutyl acrylate to ensure that the adhesive member 30 has strong adhesive force.

[0080] In one embodiment, the thickness of the support member 20 along the first direction 001 is between 0.5 mm and 2 mm.

[0081] In one embodiment, the thickness of the adhesive 30 along the first direction 001 is between 0.2 mm and 1 mm.

[0082] Please refer to the following: Figure 7 The diagram shows a planar structure of one side of the battery assembly provided in another embodiment of this application;

[0083] like Figure 2 and Figure 7 As shown, in one embodiment, the explosion-proof valve 14 is disposed at the middle of the first sidewall 12a along the length direction of the battery assembly 100. The two terminals 13 of the battery cell 10 are disposed on opposite sides of the explosion-proof valve 14 along the second direction 002, and the distances from the two terminals 13 to the explosion-proof valve 14 are equal. There is one support member 20. That is, the support member 20 is configured as a first support member 20a. The battery cell 10 includes a third sidewall 12c and a fourth sidewall 12d disposed opposite each other along the second direction 002. The distances from both ends of the first support member 20a along the second direction 002 to the third sidewall 12c and to the fourth sidewall 12d are equal, respectively. Alternatively, it can be described that the distances from both ends of the first support member 20a along the second direction 002 to the two terminals 13 are equal. In other words, the first support member 20a is disposed at the middle position of the first surface 11 of the battery cell 10 along the length direction of the first sidewall 12a.

[0084] Understandably, in this embodiment, the number of support members 20 is set to one, and it is positioned at the middle position along the length direction of the first sidewall 12a on the first surface 11 of the battery cell 10. This ensures reliable support for the support member 20 while simplifying its installation. Furthermore, since the two terminals 13 of the battery cell 10 are located at opposite ends of the first sidewall 12a, and adjacent terminals 13 of the same polarity of two battery cells 10 are connected by a connecting piece (not shown), the support member 20 is positioned at the middle position along the length direction of the first sidewall 12a of the battery cell 10 to prevent local compression of the battery cell 10 from causing the connecting piece to twist and affecting the electrical connection between the battery cells 10.

[0085] In one embodiment, the support member 20 is rectangular, and along the length direction of the battery assembly 100, the ratio of the length of the support member 20 to the length of the first sidewall 12a is between 2:5 and 7:10. That is, the ratio of the length of the support member 20 along the second direction 002 to the length of the first sidewall 12a is between 2:5 and 7:10.

[0086] Understandably, setting the length of the support member 20 along the second direction 002 within this ratio range can ensure the support effect of the support member 20 on the two adjacent cells 10, avoid the support member 20 being too small to support, resulting in too small a reserved expansion space, and also avoid setting the support member 20 too large to increase costs.

[0087] In one embodiment, the ratio of the distance from the geometric center of the support member 20 to the first sidewall 12a to the distance to the geometric center of the first surface 11 of the cell 10 is between 0 and 4:5. It should be noted that the support member 20 positioned at this location ensures sufficient reserved expansion space in the central region of the first surface 11 of the cell 10, while also guaranteeing reliable bonding between adjacent cells 10.

[0088] In one embodiment, along the length of the first sidewall 12a, the ratio of the distance from the geometric center of the adhesive 30 to its nearest sidewall 12 to the distance to the geometric center of the first surface 11 of the cell 10 is between 0 and 17:20. It should be noted that, in this embodiment, the adhesive 30 positioned at this location ensures sufficient reserved expansion space in the central region of the first surface 11 of the cell 10, while also guaranteeing reliable bonding between adjacent cells 10.

[0089] In one embodiment, the ratio of the sum of the projected areas of the support members 20 on the first surface 11 of the cell 10 to the area of ​​the first surface 11 of the cell 10 is between 0.1% and 10%; the ratio of the sum of the projected areas of the adhesive members 30 on the first surface 11 of the cell 10 to the area of ​​the first surface 11 of the cell 10 is between 20% and 70%.

[0090] It should be noted that, as can be seen from the above data, the sum of the projected areas of the adhesive 30 on the first surface 11 of the cell 10 is greater than the sum of the projected areas of the support 20 on the first surface 11 of the cell 10. This ensures that the adhesive force of the adhesive 30 on the cell 10 is greater than the supporting force of the support 20 on the cell 10, thus ensuring the stability of the stacking between adjacent cells 10 and preventing them from detaching. It also prevents the area occupied by the adhesive 30 on the first surface 11 of the cell 10 from being too large or the area occupied by the support 20 on the first surface 11 of the cell 10 from being too small, which would result in insufficient expansion space and affect heat dissipation.

[0091] In one embodiment, there are two adhesive members 30, and the two adhesive members 30 are arranged at intervals along the length direction of the battery assembly 100. The extension line of the edge of each adhesive member 30 near the geometric center of the first surface 11 forms an angle with the extension line of the edge of the first support member 20a near the geometric center of the first surface 11, and the angle range is between 60° and 100°. It can be understood that since both the support member 20 and the adhesive members 30 are elongated, and since the support member 20 is located at the middle position of the cell 10 along the length direction of the first sidewall 12a, the angle between the extension line of the edge of the first support member 20a near the geometric center of the first surface 11 and each adhesive member 30 is set to be between 60° and 100° to ensure that sufficient reserved expansion space is provided in the avoidance area 111 of the first surface 11 of the cell 10, while ensuring reliable bonding between adjacent cells 10.

[0092] Please refer to the above. Figure 8 In one embodiment, the two adhesive members 30 are in contact with the first support member 20a respectively. That is, the ratio of the area of ​​the avoidance area 111 formed by the first support member 20a, the two adhesive members 30 and the side of the first surface 11 (that is, the second sidewall 12b) on the first surface 11 of the cell 10 to the area of ​​the first surface 11 of the cell 10 is between 3:20 and 18:25.

[0093] Understandably, in this embodiment, since both the support member 20 and the adhesive member 30 are elongated, the ratio of the area of ​​the clearance area 111 formed by the support member 20 and the adhesive member 30 enclosing the first surface 11 of the cell 10 to the area of ​​the first surface 11 of the cell 10 is set between 3:20 and 18:25 to ensure sufficient reserved expansion space, while also ensuring relatively reliable adhesion between two adjacent stacked cells 10.

[0094] exist Figure 8In the illustrated embodiment, the projections of the first support member 20a and the adhesive member 30 onto the first surface 11 are both rectangular, and the first support member 20a and the adhesive member 30 are perpendicular to each other. It can be understood that this arrangement allows the shape of the avoidance area 111 to be relatively regular, optimizes the layout of the support member 20 and the adhesive member 30, and improves the reliability of the avoidance area 111.

[0095] like Figure 9 As shown, in one embodiment, the battery assembly 100 further includes a filler 40 disposed between two adjacent battery cells 10. Each battery cell 10 includes a second sidewall 12b disposed opposite to the first sidewall 12a along a third direction 003. The filler 40 and a support member 20 near the first sidewall 12a are positioned along the third direction 003 on either side of the geometric center of the first surface 11 of the battery cell 10. The filler 40 is disposed closer to the second sidewall 12b than the first sidewall 12a.

[0096] Understandably, in this embodiment, the filler adhesive 40 can cooperate with the support member 20 to support two adjacent stacked battery cells 10, thereby limiting the spacing height between the two adjacent battery cells 10 and enhancing the stability of the support. Furthermore, since the filler adhesive 40 is closer to the second sidewall 12b relative to the first sidewall 12a, sufficient reserved expansion space is ensured in the central region of the first surface 11 of the battery cell 10. Simultaneously, based on the adhesive 40's certain viscosity, it can also assist the adhesive member 30 in limiting the relative displacement between two adjacent battery cells 10.

[0097] In one embodiment, the ratio of the area of ​​the clearance area 111 formed by the support member 20, the adhesive member 30, and the filler 40 on the first surface 11 of the cell 10 to the area of ​​the first surface 11 of the cell 10 is between 1:5 and 11:20.

[0098] It should be noted that the ratio of the area of ​​the clearance area 111 formed by the support member 20, the adhesive member 30 and the filler 40 enclosing the first surface 11 of the cell 10 to the area of ​​the first surface 11 of the cell 10 is set between 1:5 and 11:20. This can provide sufficient reserved expansion space and further improve the adhesion between adjacent cells 10.

[0099] In one embodiment, along the first direction 001, the height of the support member 20 is greater than or equal to the height of the adhesive member 30. It should be noted that in the initial stage of cell 10 stacking, the height of the support member 20 is greater than the height of the adhesive member 30 to ensure the formation of reserved expansion space. During the use of the cell 10, due to the expansion of the cell 10, adjacent cells 10 are bonded together to form a sealed opening. At this time, the height of the reserved expansion space is the height of the adhesive member 30. That is, setting the height of the support member 20 to be slightly greater than or equal to the height of the adhesive member 30 ensures that a sufficiently large reserved expansion space is provided in the early stages of the cell 10's lifespan, preventing the cell 10 from being squeezed in its early lifespan and affecting its service life.

[0100] The following comparison and explanation of some embodiments of the battery module 100 of this application and a typical embodiment in the prior art illustrate the beneficial effects that the battery module 100 of this application may achieve:

[0101] It should be noted that in the following embodiments, there is one support member 20, which is located at the middle position of the cell 10 along the length of the first sidewall 12a. Simultaneously, there are two adhesive members 30, which are respectively disposed on opposite sides of the geometric center of the first surface 11 of the cell 10 along the second direction 002, with the support member 20 and the adhesive members 30 mutually surrounding each other. Since both the support member 20 and the adhesive members 30 are elongated, the area they form enclosed on the first surface 11 of the cell 10 can be considered trapezoidal or rectangular.

[0102] Where a is the distance between the two adhesive members 30 on the side closer to the support member 20 along the second direction 002; b is the distance between the two adhesive members 30 on the side farther from the support member 20 along the second direction 002; c is the length of the adhesive member 30 along the third direction 003; A is the length of the cell 10 along the second direction 002; and B is the length of the cell 10 along the third direction 003. By replacing the support member 20 and adhesive members 30 with different sizes or adjusting the relative positions of the support member 20 and adhesive members 30, the sizes of a, b, and c are changed, thereby obtaining different enclosed areas S1, that is, different sizes of reserved expansion space. Reserved expansion area: S1 = (a + b) * c / 2; Area of ​​the first surface 11 of the cell 10: S2 = A * B. The battery modules of the prior art and the battery module 100 of this application are subjected to dynamic performance tests under the same conditions. For example, the battery module 100 is cycled for charging and discharging at 28°C. After the cycle test is completed, the electrode in cell 10 is disassembled and the lithium plating on the electrode is observed. If the ratio of the lithium plating electrode area to the total electrode area is less than 10%, it is considered mild lithium plating; if it is greater than 10% but less than 50%, it is considered moderate lithium plating; and if it is greater than 50%, it is considered severe lithium plating.

[0103] The battery modules in the prior art and the battery module 100 of this application are subjected to tensile shear strength tests under the same conditions. For example, a 2kg weight is placed on the battery module and held under pressure for 2 hours. After the specified time, the two ends of the battery module are clamped and fixed using a tensile testing machine, and one of the cells is pulled out at a rate of 5mm / min to test its maximum breaking tensile force. The maximum breaking tensile force is divided by the adhesive area, that is, divided by the reserved expansion area S1, to obtain the tensile shear strength. When the shear strength is greater than 5MPa, the shear strength requirement of the battery module is met; when it is less than 5MPa, the requirement is not met.

[0104] The test results of the above experiments were statistically analyzed, and the results are shown in Table 1 below:

[0105] Table 1: where a, b, c, A, and B are all in mm; the reserved expansion area S1 and the area S2 of the first surface 11 of the battery cell 10 are both in mm2; the shear strength is MPa.

[0106]

[0107]

[0108] As can be seen from the above embodiments, the existing battery modules, due to the lack of supporting components and adhesive components to form a reserved expansion space, exhibit severe lithium plating phenomena according to kinetic results. Referring to Comparative Examples 1-7 and Examples 1-19, it can be seen that when the ratio of the reserved expansion area to the area of ​​the cell's first surface is less than 0.15, kinetic results show moderate to severe lithium plating; when the ratio is between 0.15 and 0.72, only mild lithium plating occurs; and when the ratio is greater than 0.72, slight lithium plating occurs. Therefore, when the ratio of the reserved expansion area (i.e., the area of ​​the clearance zone) to the area of ​​the cell's first surface is greater than 0.15, the cell can have sufficient expansion space, reducing lithium plating problems caused by cell expansion.

[0109] Referring again to Comparative Examples 1-7 and Examples 1-19, it can be seen that when the ratio of the reserved expansion area (i.e., the area of ​​the clearance area) to the area of ​​the first surface of the cell is greater than 0.72, the shear strength of Comparative Examples 1-3 is less than 5. Consequently, during vibration testing or impact, the top cell is prone to movement or even detachment. Therefore, when the ratio of the reserved expansion area (i.e., the area of ​​the clearance area) to the area of ​​the first surface of the cell is less than 0.72, the cell can be guaranteed to have good stability. This application sets the ratio of the reserved expansion area to the area of ​​the first surface of the cell between 0.15 and 0.72, providing sufficient reserved space for the expansion of the cell, avoiding mutual compression between cells, thereby reducing the probability of lithium plating and improving the performance and service life of the battery module. Meanwhile, as can be seen from the above data, the ratio of the reserved expansion area to the area of ​​the first surface of the cell in this application is set between 0.15 and 0.72, which also has good shear resistance. That is, the two adjacent cells stacked are firmly bonded and not easy to move, thereby improving the stability between the two adjacent cells, and thus improving the performance and service life of the battery assembly.

[0110] This application also provides a battery pack including the battery assembly described above. Specifically, the battery pack includes a tray and a sealing cover, which together enclose a receiving cavity in which the battery assembly is located.

[0111] Furthermore, this application also provides an electrical system comprising the aforementioned battery assembly or battery pack. Specifically, the electrical system can be a vehicle or an energy storage system.

[0112] like Figure 1 As shown, the vehicle 200 provided in this application includes a body 201 and a battery pack 100. The battery pack 100 is housed and fixed within the body 201, and is used to provide electrical energy to the vehicle 200 to drive it. It is understood that the battery pack 100 of this application can be applied to electric vehicles, including pure electric vehicles and hybrid electric vehicles.

[0113] It should be understood that the terms "first," "second," etc., 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, features defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of embodiments of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0114] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0115] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims. Those skilled in the art will understand that implementing all or part of the processes of the above embodiments, and making equivalent changes according to the claims of this application, still falls within the scope of this application.

Claims

1. A battery assembly, characterized in that, The device includes multiple battery cells stacked vertically. The surface of one of the battery cells between two adjacent battery cells is a first surface. The first surface is provided with a support member and an adhesive member. A clearance area is provided on the first surface. The geometric center of the first surface is located within the clearance area. The edges of the support member and the adhesive member near the geometric center of the first surface coincide with a portion of the edge of the clearance area. The extended lines of the edges of each of the support members and each of the adhesive members near the geometric center of the first surface intersect each other to form a first intersection point, and / or intersect each other with the edge of the first surface to form a second intersection point; Wherein, if all the intersections are the second intersections, the avoidance zone is the area formed by connecting multiple second intersections in sequence; If the intersection point includes a plurality of first intersection points and a plurality of second intersection points, and the first intersection points are connected in sequence to form a closed shape on the first surface, the avoidance area is the area formed by the plurality of first intersection points being connected in sequence and then enclosed. If the intersection point includes a plurality of first intersection points and a plurality of second intersection points, and the first intersection points connected in sequence cannot form a closed shape on the first surface, the avoidance area is the area formed by all the first intersection points and the plurality of second intersection points connected in sequence; The ratio of the area of ​​the avoidance zone to the area of ​​the first surface is between 3:20 and 18:25, the ratio of the sum of the projected areas of each of the supporting members on the first surface to the area of ​​the first surface is between 0.1% and 10%, and the ratio of the sum of the projected areas of each of the adhesive members on the first surface to the area of ​​the first surface is between 20% and 70%.

2. The battery assembly according to claim 1, characterized in that, The ratio of the area of ​​the avoidance zone to the area of ​​the first surface is between 1:5 and 11:

20.

3. The battery assembly according to claim 1, characterized in that, Each of the battery cells includes a first sidewall located on the same side of the battery assembly, the first sidewall being perpendicular to the first surface, the battery cell including a terminal post disposed on the first sidewall, and the support member including a first support member disposed close to the first sidewall.

4. The battery assembly according to claim 3, characterized in that, The number of terminals is two, and the two terminals are arranged at intervals along the length of the battery assembly. The number of support members is one, and the two ends of the first support member along the length of the battery assembly are equidistant from the two terminals.

5. The battery assembly according to claim 3, characterized in that, The number of adhesive components is two, and the two adhesive components are arranged at intervals along the length direction of the battery assembly; the extension line of the edge of each adhesive component near the geometric center of the first surface has an angle with the extension line of the edge of the first support near the geometric center of the first surface, and the size of the angle is between 60° and 100°.

6. The battery assembly according to claim 5, characterized in that, Along the width direction of the battery assembly, the first support member is provided on the side of the clearance area near the first sidewall. Along the length direction of the battery assembly, the adhesive members are respectively provided on both sides of the clearance area along the length direction of the battery assembly, and the two adhesive members are respectively in contact with the first support member.

7. The battery assembly according to claim 6, characterized in that, The projections of the first support member and the adhesive member onto the first surface are both rectangles, and the first support member and the adhesive member are perpendicular to each other.

8. The battery assembly according to claim 6, characterized in that, Along the width direction of the battery assembly, the battery assembly has a second sidewall opposite to the first sidewall, the second sidewall being connected to and perpendicular to the first surface; The extension line of the edge of the support member near the geometric center of the first surface intersects with the extension lines of the edges of the two adhesive members near the geometric center of the first surface, forming two first intersection points. The extension lines of the edges of the two adhesive members near the geometric center of the first surface intersect with the edge of the second sidewall, forming two second intersection points. The avoidance area is the area formed on the first surface by connecting the two first intersection points and the two second intersection points.

9. The battery assembly according to any one of claims 1-8, characterized in that, In the vertical direction, the height of the support member is greater than or equal to the height of the adhesive member.

10. The battery assembly according to any one of claims 4-8, characterized in that, The battery assembly also includes a filler adhesive disposed between two adjacent battery cells. Each battery cell includes a second sidewall disposed opposite to the first sidewall, and the filler adhesive is disposed close to the second sidewall.

11. A battery pack, characterized in that, Includes the battery assembly as described in any one of claims 1-10.

12. An electrical system, characterized in that, It includes the battery assembly as described in any one of claims 1-10, or the battery pack as described in claim 11.

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