Battery cell and battery module

Abstract

The invention relates to the technical field of energy storage equipment, in particular to a battery cell and a battery module, the battery cell comprises a main body part and an insulation part, the insulation part extends in the thickness direction and the width direction of the main body part and annularly wraps the main body part, a first groove and / or a second groove are / is formed in the main body part, the first groove is deeply formed in the thickness direction of the main body part, and the second groove is formed in the width direction of the main body part. The first groove is at least partially covered by the insulating part, and the second groove is deeply formed in the width direction of the main body part and is at least partially covered by the insulating part. Through the arrangement of the first groove and / or the second groove, the flowing path of fluid between the insulating part and the main body part in the length direction of the main body part can be increased, the flowing resistance is increased, and the sealing performance between the insulating part and the main body part is improved. The battery module comprises a module shell and a plurality of battery cells, the plurality of battery cells are arranged in the module shell, and the battery cells of the battery module have better sealing performance.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage devices, and particularly to a battery cell and a battery module. Background Art

[0002] A soft-pack battery cell generally includes a pole group provided with positive and negative pole tabs, a connecting piece for leading out the pole tabs, and a packaging material for wrapping the pole group. The commonly used packaging material is an aluminum-plastic film. Generally, there is glue coating on the connecting piece, and the aluminum-plastic film wraps the pole group and is heat-sealed to the glue coating of the connecting piece to achieve the sealing of the soft-pack battery cell at the connecting piece. However, often due to the poor sealing between the glue coating of the connecting piece and the main body of the connecting piece, the sealing of the soft-pack battery cell fails. Summary of the Invention

[0003] An object of the present invention is to provide a battery cell with better sealing performance.

[0004] To achieve this purpose, the present invention adopts the following technical solutions:

[0005] Provide a battery cell, including a connecting piece, the connecting piece includes a main body portion and an insulating portion, the insulating portion extends and wraps around the main body portion along the thickness direction and width direction of the main body portion, a first groove is formed on the main body portion, the first groove is longitudinally opened along the thickness direction of the main body portion, and at least part of the first groove is covered by the insulating portion;

[0006] And / or, a second groove is formed on the main body portion, the second groove is longitudinally opened along the width direction of the main body portion, and at least part of the second groove is covered by the insulating portion.

[0007] Optionally, the first groove is longitudinally opened through along the width direction of the main body portion;

[0008] And / or, the second groove is longitudinally opened through along the thickness direction of the main body portion.

[0009] Optionally, the size of the part of the first groove covered by the insulating portion along the length direction of the main body portion is a, the entire surface of the side wall and the bottom of the first groove covered by the insulating portion is the first covering surface, the first covering surface is sectioned along the direction perpendicular to the width direction of the main body portion to obtain a first line, and the length of the first line is L1, satisfying: 1 < L1 / a ≤ 5;

[0010] And / or, the size of the part of the second groove covered by the insulating portion along the length direction of the main body portion is b, the entire surface of the side wall and the bottom of the second groove covered by the insulating portion is the second covering surface, the second covering surface is sectioned along the direction perpendicular to the thickness direction of the main body portion to obtain a second line, and the length of the second line is L2, satisfying: 1 < L2 / b ≤ 5.

[0011] Optionally, the bottom of the first groove has a plurality of first protruding blocks, and each of the first protruding blocks is provided to penetrate along the width direction of the main body portion;

[0012] And / or, the bottom of the second groove has a plurality of second protruding blocks, and each of the second protruding blocks is provided to penetrate along the thickness direction of the main body portion.

[0013] Optionally, the first protruding block is in the shape of a triangular prism extending along the width direction of the main body portion, or the first protruding block is a wavy structure that undulates and extends along the length direction of the main body portion;

[0014] And / or, the second protruding block is in the shape of a triangular prism extending along the thickness direction of the main body portion, or the second protruding block is a wavy structure that undulates and extends along the length direction of the main body portion.

[0015] Optionally, the plurality of first protruding blocks are arranged in sequence along the length direction of the main body portion;

[0016] And / or, the plurality of second protruding blocks are arranged in sequence along the length direction of the main body portion.

[0017] Optionally, the dimension of the part of the first groove covered by the insulating portion along the length direction of the main body portion is a, and the dimension of the part of the second groove covered by the insulating portion along the length direction of the main body portion is b, and a = b is satisfied.

[0018] Optionally, the first groove is completely covered by the insulating portion;

[0019] And / or, the second groove is completely covered by the insulating portion.

[0020] Optionally, the two first grooves are oppositely opened on two surfaces of the connecting member perpendicular to its own thickness direction, the two second grooves are oppositely opened on two surfaces of the connecting member perpendicular to its own width direction, and any two adjacent ones of the two first grooves and the two second grooves are at least partially communicated.

[0021] Another object of the present invention is to provide a battery module, and its battery cells have good sealing performance.

[0022] To achieve this object, the present invention adopts the following technical solutions:

[0023] Provide a battery module, including a module housing and a plurality of the above-mentioned battery cells, and the plurality of battery cells are all arranged in the module housing.

[0024] Advantages of the present invention:

[0025] The present invention provides an electric core, including a connecting member. The connecting member includes a main body portion and an insulating portion. The insulating portion extends and is annularly arranged along the thickness direction and the width direction of the main body portion to wrap the main body portion. A first groove is formed in the main body portion, and the first groove is longitudinally formed along the thickness direction of the main body portion, and at least part of the first groove is covered by the insulating portion. And / or, a second groove is formed in the main body portion, and the second groove is longitudinally formed along the width direction of the main body portion, and at least part of the second groove is covered by the insulating portion. By providing the first groove and / or the second groove, the flow path of the fluid flowing along the length direction of the main body portion from the gap between the insulating portion and the main body portion will increase, and the flow resistance will increase, which can help reduce the fluid from flowing into the gap between the insulating portion and the main body portion and improve the sealing performance between the insulating portion and the main body portion. And by providing the first groove and / or the second groove, the friction between the insulating portion and the main body portion can be increased, further improving the difficulty of their mutual separation or dislocation, thereby further preventing the sealing performance from failing.

[0026] The present invention further provides a battery module, including a module housing and a plurality of the above-mentioned electric cores. The plurality of electric cores are all arranged in the module housing, and the electric cores of this battery module have good sealing performance. Description of the Drawings

[0027] Figure 1 is a schematic structural diagram of the electric core from the first perspective provided by an embodiment of the present invention;

[0028] Figure 2 is an exploded view of the electric core provided by an embodiment of the present invention;

[0029] Figure 3 is an exploded view of the connecting member provided by an embodiment of the present invention;

[0030] Figure 4 is a schematic structural diagram of the electric core from the second perspective provided by an embodiment of the present invention;

[0031] Figure 5 is Figure 4 the A-A cross-sectional view in ;

[0032] Figure 6 is Figure 5 the enlarged view at B in ;

[0033] Figure 7 is the cross-sectional view of the connecting member provided by an embodiment of the present invention;

[0034] Figure 8 is Figure 7 the enlarged view at C in ;

[0035] Figure 9 is the schematic structural diagram of the connecting member provided by an embodiment of the present invention;

[0036] Figure 10Yes Figure 9 An enlarged view of the position D in the figure;

[0037] Figure 11 It is a schematic structural view of the main body part (adjacent parts are all connected) of the connector provided by an embodiment of the present invention;

[0038] Figure 12 It is a schematic structural view of the main body part (adjacent parts are not connected) of the connector provided by an embodiment of the present invention.

[0039] In the figure:

[0040] 1. Connector; 11. Main body part; 111. First groove; 1111. First protruding block; 1101. First surface; 1102. Second surface; 112. Second groove; 12. Insulating part;

[0041] 2. Electrode group; 21. Tab; 3. Encapsulation film;

[0042] 100. Battery cell. Detailed implementation manners

[0043] Before explaining any embodiment of the present application in detail, it should be understood that the present application is not limited to the structural details and component arrangements described in the following description or shown in the above drawings.

[0044] In the present application, the terms "include", "comprise", "have" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including that element.

[0045] In the present application, the term "and / or" is a relationship describing associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the present application, the character " / " generally represents an "and / or" relationship between the associated objects before and after.

[0046] In this application, the terms "connected", "combined", "coupled", and "mounted" can be direct connections, combinations, couplings, or mountings, or can be indirect connections, combinations, couplings, or mountings. Among them, by way of example, a direct connection means that two parts or components are connected together without the need for an intermediate member, and an indirect connection means that two parts or components are respectively connected to at least one intermediate member, and these two parts or components are connected through the intermediate member. In addition, "connected" and "coupled" are not limited to physical or mechanical connections or couplings, and can include electrical connections or couplings.

[0047] In this application, those of ordinary skill in the art will understand that relative terms used in connection with a quantity or condition (such as "about", "approximately", "substantially", etc.) are intended to include the recited value and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances resulting from manufacturing, assembly, use in relation to a particular value, etc. Such terms should also be considered to disclose a range defined by the absolute values of two endpoints. A relative term may refer to a plus or minus a certain percentage (such as 1%, 5%, 10% or more) of the indicated value. Numerical values that do not employ relative terms should also be disclosed as having tolerances. In addition, when expressing a relative angular positional relationship (such as substantially parallel, substantially perpendicular), "substantially" may refer to a plus or minus a certain number of degrees (such as 1 degree, 5 degrees, 10 degrees or more) from the indicated angle.

[0048] In this application, those of ordinary skill in the art will understand that the functions performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the functions performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0049] In this application, the directional terms such as "upper", "lower", "left", "right", "front", "rear", etc. are described based on the orientation and positional relationship shown in the drawings, and should not be construed as limiting the embodiments of this application. In addition, in the context, it should also be understood that when it is mentioned that one element is connected "above" or "below" another element, it can not only be directly connected "above" or "below" another element, but also be indirectly connected "above" or "below" another element through an intermediate element. It should also be understood that directional terms such as the upper side, lower side, left side, right side, front side, rear side, etc. not only represent the positive direction, but can also be understood as the side direction. For example, the lower side can include directly below, lower left, lower right, lower front, and lower rear, etc.

[0050] A battery cell generally includes an electrode assembly provided with positive and negative electrode tabs, a connecting piece for leading out the electrode tabs, and a packaging material for wrapping the electrode assembly. The commonly used packaging material is a packaging film. Generally, the connecting piece is provided with glue coating. The packaging film wraps the electrode assembly and is heat-melted and connected to the glue coating of the connecting piece to achieve the sealing of the battery cell at the connecting piece. However, often due to the poor sealing between the glue coating of the connecting piece and the main body of the connecting piece, the sealing of the battery cell fails.

[0051] Therefore, this embodiment provides a battery cell 100 to solve the above problems, and the battery cell 100 has good sealing performance.

[0052] As Figures 1 - 10 shown, the battery cell 100 of this embodiment includes a connecting piece 1. The connecting piece 1 includes a main body portion 11 and an insulating portion 12. The insulating portion 12 extends and is annularly arranged along the thickness direction and the width direction of the main body portion 11 to wrap the main body portion 11. The main body portion 11 is provided with a first groove 111 and / or a second groove 112. The first groove 111 is longitudinally opened along the thickness direction of the main body portion 11, and at least part of the first groove 111 is covered by the insulating portion 12. The second groove 112 is longitudinally opened along the width direction of the main body portion 11, and at least part of the second groove 112 is covered by the insulating portion 12. That is, the first groove 111 is opened on the end surface of the main body portion 11 perpendicular to its own thickness direction, and the second groove 112 is opened on the end surface of the main body portion 11 perpendicular to its own width direction.

[0053] By providing the first groove 111 and / or the second groove 112, the path for the fluid to flow along the length direction of the main body portion 11 from the gap between the insulating portion 12 and the main body portion 11 will increase, and the flow resistance will increase, which can help reduce the fluid flowing into the gap between the insulating portion 12 and the main body portion 11 and improve the sealing between the insulating portion 12 and the main body portion 11. And by providing the first groove 111 and / or the second groove 112, the friction between the insulating portion 12 and the main body portion 11 can be increased, further improving the difficulty of their mutual separation or dislocation, thereby further preventing the sealing failure between the insulating portion 12 and the main body portion 11.

[0054] Optionally, the battery cell 100 further includes a pole group 2 and a packaging film 3. Pole tabs 21 are provided at both opposite ends of the pole group 2, which are a positive pole tab and a negative pole tab respectively. The battery cell 100 is provided with two connecting members 1, one is connected to the positive pole tab and the other is connected to the negative pole tab. Optionally, the connecting members 1 are welded to both pole tabs 21 to ensure the connection strength. The packaging film 3 completely wraps the pole group 2, and the pole group 2 is sealed in the packaging film 3 by a hot melting method. The width of the outer layer of the insulating portion 12 is greater than the width of the main body portion 11, and the thickness of the outer layer of the insulating portion 12 is greater than the thickness of the main body portion 11. The insulating portion 12 completely wraps the main body portion 11, and the packaging film 3 near the insulating portion 12 is hot melt connected to the insulating portion 12, which can ensure the relative fixation of the packaging film 3 and the insulating portion 12, that is, the relative fixation between the packaging film 3 and the main body portion 11 can be ensured. The other regions are hot melt connected by the upper and lower two layers of packaging film 3 to form a sealed space for accommodating the pole group 2 between the two layers of packaging film 3.

[0055] Optionally, the first groove 111 is opened through along the width direction of the main body portion 11. Then, along the width direction of the main body portion 11, the gas flow resistance at each place increases, and the path length increases, which can further improve the interception effect on the fluid.

[0056] Optionally, the second groove 112 is opened through along the thickness direction of the main body portion 11. Similarly, opening through can achieve that along the width direction of the main body portion 11, the gas flow resistance at each place increases, and the path length increases, which can further improve the interception effect on the fluid.

[0057] Optionally, the two first grooves 111 are oppositely opened on two surfaces of the connecting member 1 perpendicular to its own thickness direction, and the two second grooves 112 are oppositely opened on two surfaces of the connecting member 1 perpendicular to its own width direction. Any two adjacent ones of the two first grooves 111 and the two second grooves 112 are at least partially communicated. That is, grooves are opened on the four surfaces that the fluid will flow through along the length direction of the main body portion 11, which can ensure that the sealing performance of the four surfaces is improved.

[0058] As Figure 3 shown, the two first grooves 111 and the two second grooves 112 are sequentially communicated and any two adjacent ones are aligned at both ends along the length direction of the main body portion 11. As Figure 11 shown, any two adjacent ones of the two first grooves 111 and the two second grooves 112 are misaligned and communicated. Such a setting can also block the escape path of the fluid. As Figure 12 shown, it can also be set that any two adjacent ones of the two first grooves 111 and the two second grooves 112 are not communicated, that is, any two adjacent ones are completely staggered. This will leave an escape path for the fluid, but is beneficial to the structural strength of the main body portion 11 and can be adjusted according to actual needs.

[0059] Optionally, the bottom of the first groove 111 has a plurality of first protruding blocks 1111, and each first protruding block 1111 is provided through along the width direction of the main body portion 11. Arranging the plurality of first protruding blocks 1111 can further extend the flow path of the fluid along the length direction of the main body portion 11 and increase the flow resistance. The fact that the first protruding blocks 1111 are provided through along the width direction of the main body portion 11 can ensure that the flow paths and flow resistances at various places on the bottom of the first groove 111 are consistent.

[0060] Optionally, the first protruding block 1111 is a triangular prism structure extending along the width direction of the main body portion 11, or the first protruding block 1111 is a wavy structure that undulates and extends along the length direction of the main body portion 11. Taking the first protruding block 1111 as a triangular prism structure extending along the width direction of the main body portion 11 as an example, as Figure 8 shown, the first protruding block 1111 has a first surface 1101 and a second surface 1102. When the fluid flows through the surface of the triangular prism structure, energy will be consumed and the speed will be reduced at the bending places, further increasing the flow resistance. Compared with setting a wavy curved surface, the flow resistance of the bending surface is greater.

[0061] Optionally, a plurality of first protruding blocks 1111 are provided at the bottoms of the two relatively arranged first grooves 111. In this embodiment, the plurality of first protruding blocks 1111 arranged in the two first grooves 111 are arranged in mirror symmetry, that is, along the length direction of the main body portion 11, the area of the internal cross-section will have fluctuations of increase and decrease. Therefore, in other embodiments, the plurality of first protruding blocks 1111 in the two first grooves 111 can also be arranged staggeredly to minimize the size fluctuations of the cross-sectional area of the main body portion 11 along the length direction of the main body portion 11, that is, to maximize the area of the minimum cross-section as much as possible and ensure the flow guiding ability of the main body portion 11.

[0062] Optionally, the plurality of first protruding blocks 1111 are arranged in sequence along the length direction of the main body portion 11. When the length of the bottom of the first groove 111 remains unchanged along the length direction of the main body portion 11, adding a plurality of first protruding blocks 1111 can extend the fluid path. And when the fluid paths are the same, relatively many but shorter first protruding blocks 1111 can be set, or relatively few but higher first protruding blocks 1111 can be set. Obviously, the former can increase the number of bending places, increase the flow resistance, and is more conducive to increasing the minimum cross-section of the main body portion 11, improving the flow guiding ability of the main body portion 11, and is also more conducive to ensuring the structural strength of the main body portion 11. Further optionally, the plurality of first protruding blocks 1111 are connected in sequence along the length direction of the main body portion 11 to extend the fluid path to the greatest extent.

[0063] Optionally, the bottom of the second groove 112 has a plurality of second protruding blocks (not shown in the figure), and each second protruding block penetrates along the thickness direction of the main body portion 11. Providing a plurality of second protruding blocks can also further extend the flow path of the fluid along the length direction of the main body portion 11 and increase the flow resistance. The fact that the second protruding blocks penetrate along the thickness direction of the main body portion 11 can ensure that the flow paths and flow resistances at all parts of the bottom of the second groove 112 are consistent.

[0064] Optionally, the second protruding block is a triangular prism structure extending along the thickness direction of the main body portion 11, or the second protruding block is a wavy structure that undulates and extends along the length direction of the main body portion 11. Similarly, when the fluid flows through the surface of the triangular prism structure, energy will be consumed and the speed will be reduced at the bending places, further increasing the flow resistance. Compared with setting a wavy curved surface, the flow resistance of the bending surface is greater.

[0065] Optionally, a plurality of second protruding blocks are provided at the bottoms of the two oppositely arranged second grooves 112. In this embodiment, the plurality of second protruding blocks provided in the two second grooves 112 are arranged in mirror symmetry, that is, along the length direction of the main body portion 11, the area of the internal cross-section will fluctuate with increases and decreases. Therefore, in other embodiments, the plurality of second protruding blocks in the two second grooves 112 can also be arranged staggeredly to minimize the size fluctuation of the cross-section of the main body portion 11 along the length direction of the main body portion 11, that is, to maximize the area of the minimum cross-section as much as possible and ensure the flow guiding ability of the main body portion 11.

[0066] Optionally, the plurality of second protruding blocks are arranged in sequence along the length direction of the main body portion 11. When the length of the bottom of the second groove 112 remains unchanged along the length direction of the main body portion 11, adding a plurality of second protruding blocks can extend the fluid path. And when the fluid paths are the same, relatively more but shorter second protruding blocks can be provided, or relatively fewer but taller second protruding blocks can be provided. Obviously, the former can increase the number of bending places, increase the flow resistance, and is more conducive to increasing the minimum cross-section of the main body portion 11 and improving the flow guiding ability of the main body portion 11, and is also more conducive to ensuring the structural strength of the main body portion 11. Further optionally, the plurality of second protruding blocks are connected in sequence along the length direction of the main body portion 11 to extend the fluid path to the greatest extent.

[0067] As Figure 8 shown, optionally, the dimension of the portion of the first groove 111 covered by the insulating portion 12 along the length direction of the main body portion 11 is a. The entire surface of the side wall and the bottom of the first groove 111 covered by the insulating portion 12 is the first covering surface. After the first covering surface is sectioned along the direction perpendicular to the width direction of the main body portion 11, a first line is obtained, and the length of the first line is L1, that is Figure 8The sum of the lengths of the line segments at the side walls of the first groove 111 and the sum of the lengths of the multiple broken lines at the bottom of the groove. The dimension a in the length direction of the main body 11 of the part of the first groove 111 covered by the insulating part 12 and the length L1 of the first line satisfy: 1 < L1 / a ≤ 5.

[0068] When the first groove 111 is completely covered by the insulating part 12, the first covering surface includes all the surfaces of the side walls and the bottom of the first groove 111. One end of the first line is located at the upper edge of one side wall of the first groove 111, and the other end of the first line is located at the upper edge of the other side wall of the first groove 111. Taking the example that the bottom of the first groove 111 is provided with a first protruding block 1111 in the shape of a triangular prism, as Figure 8 shown, the left starting point of the first line is located at the upper edge of the left side wall of the first groove 111. As the first line extends, the first line first passes through the second surface 1102 of the first triangular prism-shaped structure, and then will successively pass through the first surfaces 1101 and the second surfaces 1102 of multiple triangular prism-shaped structures, and finally passes through the right side wall of the first groove 111, and the right end point of the first line is located at the upper edge of the right side wall of the first groove 111.

[0069] When L1 is equal to a, there is no first groove 111. When the ratio of L1 to a is greater than 5, that is, L1 is too large. With a unchanged, the ways to increase L1 include deepening the depth of the first groove 111, or setting the undulation degree of the inclined surface or curved surface at the bottom to be greater. However, such a design will, on the one hand, increase the processing difficulty of the first groove 111, and on the other hand, reduce the structural strength at the first groove 111, which is not conducive to the quality stability of the battery cell 100, and the cross-sectional area of the first groove 111 changes too much in the direction perpendicular to the length direction, which is not conducive to the stability of current conduction. Therefore, the ratio of L1 to a being less than or equal to 5 can intercept the fluid from flowing into the space between the insulating part 12 and the main body 11 while ensuring the structural strength of the main body 11 and the stability of current conduction, and improve the quality stability of the battery cell 100 from multiple dimensions. The effects of the above-mentioned dimension data limitations will be further corroborated by experimental data below.

[0070] As Figure 10 shown, optionally, the dimension of the part of the second groove 112 covered by the insulating part 12 in the length direction of the main body 11 is b. The entire surface of the side walls and the bottom of the second groove 112 covered by the insulating part 12 is the second covering surface. After the second covering surface is sectioned along the thickness direction perpendicular to the main body 11, a second line is obtained, and the length of the second line is L2, that is, Figure 10 the sum of the lengths of the line segments at the side walls of the second groove 112 and the sum of the lengths of the line segments at the bottom of the groove in

[0071] When the second groove 112 is completely covered by the insulating portion 12, the second covering surface includes all the surfaces of the side wall and the bottom of the second groove 112. One end of the second wire is located at the upper edge of one side wall of the second groove 112, and the other end of the second wire is located at the upper edge of the other side wall of the second groove 112. Taking the example that no second protruding block is provided at the bottom of the second groove 112, as Figure 10 shown, the left starting point of the second wire is located at the upper edge of the left side wall of the second groove 112. The second wire passes through the left side wall and the bottom of the second groove 112 and reaches the right side wall of the second groove 112, and the right end point of the second wire is located at the upper edge of the right side wall of the second groove 112.

[0072] Similarly, when L2 is equal to b, that is, when there is no second groove 112, and when the ratio of L2 to b is greater than 5, that is, L2 is too large. With b unchanged, the ways to increase L2 include deepening the depth of the second groove 112 or increasing the undulation degree of the inclined surface or curved surface at the bottom. The above design will increase the processing difficulty of the second groove 112 on the one hand, and reduce the structural strength at the second groove 112 on the other hand, which is not conducive to the quality stability of the battery cell 100. Moreover, the cross-sectional area of the second groove 112 changes too much along the direction perpendicular to the length direction, which is not conducive to the stability of current conduction. Therefore, when the ratio of L2 to b is less than or equal to 5, while intercepting the fluid from flowing into the space between the insulating portion 12 and the main body portion 11, the structural strength of the main body portion 11 and the stability of current conduction can be ensured, improving the quality stability of the battery cell 100 from multiple dimensions. The following will further prove the effect of the above-mentioned dimensional data limitations with experimental data.

[0073] Table 1

[0074]

[0075] The above table provides battery cells 100 of five embodiments and battery cells 100 of six comparative examples. The test contents include the sealing performance test of the battery cell 100, the processing time of the connecting member 1, the yield rate of the connecting member 1, and the structural strength test of the connecting member 1.

[0076] Among them, the main body portions 11 of the connecting members 1 of the battery cells 100 in Embodiments 1 - 5 all meet the design standards of 1 < L1 / a ≤ 5 and 1 < L2 / b ≤ 5. The battery cells 100 of these five embodiments all meet the sealing requirements, and the connecting member 1 has a short processing time, a high yield rate, and a structural strength that meets the requirements, showing high quality.

[0077] For the battery cell 100 of Comparative Example 1, the main body portion 11 of the connecting member 1 is not provided with the first groove 111 and the second groove 112. The structural strength of the main body portion 11 is good, but the sealing performance is poor, and there is still a problem of sealing failure.

[0078] For the connecting member 1 of the battery cell 100 of Comparative Example 2, the main body portion 11 is not provided with the first groove 111, but only the second groove 112 is provided, that is, grooves are only provided on both sides in the width direction of the main body portion 11, and no groove is provided on the end face perpendicular to the thickness direction of the main body portion 11, that is, the end face with the largest area. Experiments have proved that the sealing effect of the battery cell 100 of Comparative Example 2 is not good, but compared with the battery cell 100 of Comparative Example 1, the sealing performance of the battery cell 100 of Comparative Example 2 has been improved.

[0079] For the connecting member 1 of the battery cell 100 of Comparative Example 3, the main body portion 11 is not provided with the second groove 112, but only the first groove 111 is provided, that is, grooves are only provided on the end face perpendicular to the thickness direction of the main body portion 11, that is, the end face with the largest area. Experiments have proved that the sealing effect of the battery cell 100 of Comparative Example 3 is not good, but compared with the battery cell 100 of Comparative Example 1, the sealing performance of the battery cell 100 of Comparative Example 3 has also been improved.

[0080] For the connecting member 1 of the battery cell 100 of Comparative Example 4, the main body portion 11 is provided with the first groove 111 and the second groove 112, but the ratio of L2 to b of the second groove 112 is greater than 5, that is, L2 is too large. The forming difficulty of the main body portion 11 increases, the processing time increases, the yield rate of the main body portion 11 decreases, and the structural strength of the main body portion 11 at the second groove 112 is weak, posing a quality hazard.

[0081] For the connecting member 1 of the battery cell 100 of Comparative Example 5, the main body portion 11 is provided with the first groove 111 and the second groove 112, but the ratio of L1 to a of the first groove 111 is greater than 5, that is, L1 is too large. The forming difficulty of the main body portion 11 increases, the processing time increases, the yield rate of the main body portion 11 decreases, and the structural strength of the main body portion 11 at the first groove 111 is weak, posing a quality hazard.

[0082] For the connecting member 1 of the battery cell 100 of Comparative Example 6, the main body portion 11 is provided with the first groove 111 and the second groove 112, but the ratio of L1 to a of the first groove 111 is greater than 5, that is, L1 is too large, and the ratio of L2 to b of the second groove 112 is also greater than 5, that is, L2 is also too large. The forming difficulty of the main body portion 11 further increases, the processing time increases, the yield rate of the main body portion 11 further decreases, and the structural strength of the main body portion 11 at the first groove 111 is weaker, increasing the quality hazard.

[0083] The above experimental results further confirm that when the main body portion 11 of the battery cell 100 is provided with both the first groove 111 and the second groove 112 and the relevant dimensions meet the above ratio requirements, the battery cell 100 can ensure the sealing performance and structural strength, ensuring the quality stability of the battery cell 100 from multiple dimensions.

[0084] Optionally, the dimension a of the portion of the first groove 111 covered by the insulating portion 12 in the length direction of the main body portion 11 and the dimension b of the portion of the second groove 112 covered by the insulating portion 12 in the length direction of the main body portion 11 satisfy a = b. Further preferably, L1 = L2, that is, the flow path lengths of the fluid flowing through the first groove 111 and the second groove 112 are the same, which can ensure that the probability and time of fluid inflow at each place are basically the same, and prevent the occurrence of weak areas of fluid inflow.

[0085] Optionally, the first groove 111 is completely covered by the insulating portion 12, which can not only improve the effect of the first groove 111 on enhancing the sealing performance, but also enable the first groove 111, that is, the thinner part of the main body portion 11, to be wrapped and protected by the insulating portion 12. Optionally, the second groove 112 is completely covered by the insulating portion 12. Similarly, it can not only improve the effect of the second groove 112 on enhancing the sealing performance, but also enable the second groove 112, that is, the narrower part of the main body portion 11, to be wrapped and protected by the insulating portion 12.

[0086] By providing the first groove 111 and the second groove 112 in the battery cell 100, the path of the fluid flowing from any surface of the main body portion 11 along the length direction of the main body portion 11 through the gap between the insulating portion 12 and the main body portion 11 will increase, and the flow resistance will increase, which can help reduce the fluid flowing into the gap between the insulating portion 12 and the main body portion 11 and improve the sealing performance between the insulating portion 12 and the main body portion 11. And by providing the first groove 111 and the second groove 112, the friction between the insulating portion 12 and the main body portion 11 can be increased, further improving the difficulty of their mutual separation or dislocation, thereby further preventing the sealing failure between the insulating portion 12 and the main body portion 11. By precisely designing the size ratio of the first groove 111 and the second groove 112, the battery cell 100 can reduce the fluid flowing into the gap between the insulating portion 12 and the main body portion 11, ensure high sealing performance, and at the same time ensure the structural strength of the main body portion 11 and the stability of current conduction, improving the quality of the battery cell 100 from multiple dimensions.

[0087] The present invention also provides a battery module, including a module housing and a plurality of the above-mentioned battery cells 100, and a plurality of battery cells 100 are all arranged in the module housing. Optionally, a plurality of battery cells 100 are stacked.

[0088] The battery cell 100 of this battery module has good sealing performance, and its conductive connecting member 1 has good structural strength and current conduction stability, which helps to ensure the quality stability of the battery module.

[0089] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. A battery cell, characterized in that: The connector (1) comprises a main body (11) and an insulating part (12), the insulating part (12) extending in a thickness direction and a width direction of the main body (11) and being arranged around the main body (11), the main body (11) being provided with a first groove (111), the first groove (111) being provided in a depth along the thickness direction of the main body (11), and the first groove (111) being at least partially covered by the insulating part (12); And / or, a second groove (112) is provided on the main body (11), the second groove (112) is provided in a longitudinal direction along the width direction of the main body (11), and the second groove (112) is at least partially covered by the insulating part (12).

2. The battery cell according to claim 1, characterized in that: The first groove (111) is formed through the main body (11) in a width direction thereof; And / or, the second groove (112) is opened through the main body (11) in the thickness direction.

3. The battery cell according to claim 2, characterized in that: The size of the portion of the first groove (111) covered by the insulating portion (12) along the length direction of the main body (11) is a, and the entire surface of the side wall and the groove bottom of the first groove (111) covered by the insulating portion (12) is a first covering surface. The first covering surface is obtained by taking a cross section perpendicular to the width direction of the main body (11) to obtain a first line, and the length of the first line is L1, which satisfies: 1<L1 / a≤5; And / or, the dimension of the portion of the second groove (112) covered by the insulating portion (12) along the length direction of the main body (11) is b, the entire surface of the side wall and the groove bottom of the second groove (112) covered by the insulating portion (12) is a second covering surface, and the second covering surface is obtained by cutting a second line along a section perpendicular to the thickness direction of the main body (11), and the length of the second line is L2, satisfying: 1<L2 / b≤5.

4. The battery cell according to any one of claims 1 to 3, characterized in that: The bottom of the first groove (111) has a plurality of first protruding blocks (1111), and each of the first protruding blocks (1111) is arranged through the width direction of the main body (11); And / or, the bottom of the second groove (112) has a plurality of second protruding blocks, and each of the second protruding blocks is arranged to penetrate along the thickness direction of the main body (11).

5. The battery cell according to claim 4, characterized in that: The first protruding block (1111) is in the shape of a triangular prism extending in the width direction of the main body (11), or the first protruding block (1111) is in the shape of a wave structure, and the wave structure extends in an undulating manner in the length direction of the main body (11); And / or, the second protruding block is in the shape of a triangular prism extending in the thickness direction of the main body (11), or the second protruding block is in the shape of a wave structure, and the wave structure extends in an undulating manner along the length direction of the main body (11).

6. The battery cell according to claim 4, characterized in that: A plurality of the first protruding blocks (1111) are arranged in sequence along the length direction of the main body (11); And / or, a plurality of the second protruding blocks are arranged in sequence along the length direction of the main body (11).

7. The battery cell according to any one of claims 1 to 3, characterized in that: The dimension of the portion of the first groove (111) covered by the insulating portion (12) along the length direction of the main body (11) is a, and the dimension of the portion of the second groove (112) covered by the insulating portion (12) along the length direction of the main body (11) is b, satisfying a=b.

8. The battery cell according to any one of claims 1 to 3, characterized in that: The first groove (111) is completely covered by the insulating portion (12); And / or, the second groove (112) is completely covered by the insulating part (12).

9. The battery cell according to any one of claims 1 to 3, characterized in that: The two first grooves (111) are relatively opened on two surfaces of the connecting member (1) perpendicular to its thickness direction, and the two second grooves (112) are relatively opened on two surfaces of the connecting member (1) perpendicular to its width direction, and any two adjacent ones of the two first grooves (111) and the two second grooves (112) are at least partially connected.

10. A battery module, characterized in that: It comprises a module casing and a plurality of battery cells according to any one of claims 1 to 9, wherein the plurality of battery cells (100) are arranged in the module casing.

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