Top cover structure, battery cell and battery module

Abstract

The present invention relates to the technical field of energy storage devices, and particularly to a top cover structure, a battery cell, and a battery module. The top cover structure includes a cover plate and a first plastic part. The first plastic part is attached to the side of the cover plate facing the inside of the battery. The cover plate is provided with a first positioning structure, and the first plastic part is provided with a pole post through hole and a second positioning structure. The first positioning structure and the second positioning structure are in concave-convex fit to limit the relative position of the first plastic part and the cover plate. The second positioning structure includes M groups of positioning parts. Along the length direction of the first plastic part, starting from the center of the pole post through hole, a group of positioning parts is set at every preset length W. The preset length W satisfies..., and M is a positive integer. The battery cell includes a housing and the above-mentioned top cover structure. The top cover structure is hermetically arranged at the opening of the housing to form a battery cell housing. The battery module includes a battery housing and at least one of the above-mentioned battery cells. At least one battery cell is arranged inside the battery housing.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage devices, and in particular, to a top cover structure, an electric core, and a battery module. Background Art

[0002] Existing blade electric cores generally adopt a structural design with electrode tabs protruding from both sides. Therefore, the positive electrode post and the negative electrode post are respectively arranged on the cover plates at both ends. Due to the pressing and fixing of the electrode posts at the position of the lower plastic, there will be no phenomena such as movement or deviation at this position of the lower plastic. However, there is no additional limiting structure or the limiting structure design is unreasonable on the other side of the lower plastic far from the electrode posts, resulting in frequent skewing of the lower plastic under the cover plate, non - coincidence of the center lines at both ends, deformation and displacement of the lower plastic. During the use of the electric core, problems such as poor heat - melting insulating film, scratching of the cover plate or the electrode group during shell insertion, tearing of the electrode tabs, abnormal peripheral welding and helium leak detection also occur, which greatly affects the yield and efficiency of the electric core manufacturing process. At the same time, the electric core also has relatively large potential safety risks. Summary of the Invention

[0003] An object of the present invention is to provide a top cover structure that can improve the yield and efficiency of the electric core manufacturing process.

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

[0005] Provide a top cover structure, including a cover plate and a first plastic part. The first plastic part is attached to the side of the cover plate facing the inside of the battery. The cover plate is provided with a first positioning structure, and the first plastic part is provided with electrode post through - holes and a second positioning structure. The first positioning structure and the second positioning structure are in concave - convex fit to limit the relative position of the first plastic part and the cover plate. The second positioning structure includes M groups of positioning parts. Along the length direction of the first plastic part, starting from the center of the electrode post through - hole, each group of positioning parts is set at intervals of a preset length W. The preset length W satisfies , where M is a positive integer.

[0006] Optionally, when the width L of the first plastic part is less than 20 mm, along the width direction of the first plastic part, each group of positioning parts includes one positioning part.

[0007] Optionally, the width H of the positioning part satisfies ;

[0008] And / or, the width H of each positioning part and the width L of the first plastic part satisfy .

[0009] Optionally, the center of the positioning part is located on the center line in the width direction of the first plastic part.

[0010] Optionally, when the width L of the first plastic part is greater than or equal to 20 mm, in the width direction of the first plastic part, each group of the positioning parts includes two of the positioning parts arranged at intervals.

[0011] Optionally, the distance W1 between the centers of the two positioning parts in each group satisfies ;

[0012] And / or, the distance W1 between the centers of the two positioning parts in each group and the width L of the first plastic part satisfy ;

[0013] And / or, the width H of each positioning part satisfies 。

[0014] Optionally, the two positioning parts in each group are symmetrically arranged along the center line in the width direction of the first plastic part.

[0015] Optionally, the pole post through hole is arranged near the first end of the first plastic part along the length direction, the second end of the first plastic part is arranged opposite to the first end, M takes a value of 1, the positioning part is located between the pole post through hole and the second end, and the distance W2 between the center of the positioning part and the second end satisfies 。

[0016] Another object of the present invention is to provide an electric core, which can improve the yield and efficiency of the electric core manufacturing process.

[0017] To achieve this purpose, the present invention adopts the following technical solutions:

[0018] Provide an electric core, including a housing and the above-mentioned top cover structure, and the top cover structure is hermetically arranged at the opening of the housing to form an electric core outer shell.

[0019] Another object of the present invention is to provide a battery module, which can improve the yield and efficiency of the electric core manufacturing process.

[0020] To achieve this purpose, the present invention adopts the following technical solutions:

[0021] Provide a battery module, including a battery outer shell and at least one of the above-mentioned electric cores, and at least one of the electric cores is arranged in the battery outer shell.

[0022] The beneficial effects of the present invention:

[0023] The present invention provides a top cover structure, which includes a cover plate and a first plastic part. The first plastic part is attached to the side of the cover plate facing the inside of the battery. The cover plate is provided with a first positioning structure, and the first plastic part is provided with a pole post through hole and a second positioning structure. The first positioning structure and the second positioning structure are in concave-convex fit to limit the relative position of the first plastic part and the cover plate, thereby preventing the first plastic part from shifting at the second positioning structure of the first plastic part. The second positioning structure includes M groups of positioning parts. Along the length direction of the first plastic part, starting from the center of the pole post through hole, a group of positioning parts is set at every preset length W. The preset length W satisfies that, , where M is a positive integer. By reasonably designing the position of the second positioning structure, it can be ensured that the end of the first plastic part far from the pole post through hole does not have problems such as shifting and deformation, thereby avoiding problems such as poor hot-melt insulating film, scratching the cover plate or the pole group and the pole ear during shell insertion, pole ear tearing, abnormal peripheral welding and helium detection, and improving the yield and efficiency of the battery cell manufacturing process.

[0024] The present invention also provides a battery cell, which includes a housing and the above-mentioned top cover structure. The top cover structure is sealed at the opening of the housing to form the battery cell housing. This battery cell can improve the yield and efficiency of the battery cell manufacturing process.

[0025] The present invention also provides a battery module, which includes a battery housing and at least one of the above-mentioned battery cells. At least one battery cell is arranged in the battery housing. This battery module can improve the yield and efficiency of the battery cell manufacturing process. Description of the Drawings

[0026] Figure 1 is an exploded view of the top cover structure provided in the first embodiment of the present invention from the first perspective;

[0027] Figure 2 is an exploded view of the top cover structure provided in the first embodiment of the present invention from the second perspective;

[0028] Figure 3 is a schematic structural diagram of the first plastic part provided in the first embodiment of the present invention;

[0029] Figure 4 is a schematic structural diagram of the first plastic part provided in the second embodiment of the present invention from the third perspective;

[0030] Figure 5 is a schematic structural diagram of the first plastic part provided in the second embodiment of the present invention from the fourth perspective;

[0031] Figure 6 is an exploded view of the battery cell provided in the third embodiment of the present invention.

[0032] In the figure:

[0033] 1. Cover plate; 11. First positioning structure;

[0034] 2. First plastic part; 21. Positioning part;

[0035] 3. Riveting block; 4. Upper plastic; 5. Sealing ring; 6. Terminal post;

[0036] 100. Top cover structure; 200. Housing; 300. Electrode group; 400. Insulating film. Detailed implementation manners

[0037] Before explaining any implementation manner 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.

[0038] In the present application, the term "comprise", "include", "have" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0039] In the present application, the term "and / or" describes the associative relationship of associated objects and indicates that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in the present application generally represents an "and / or" relationship between the front and rear associated objects.

[0040] In the present application, the terms "connect", "combine", "couple", "mount" may be direct connection, combination, coupling or mounting, or may be indirect connection, combination, coupling or mounting. Among them, by way of example, direct connection means that two parts or components are connected together without setting an intermediate member, and 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, "connect" and "couple" are not limited to physical or mechanical connection or coupling, and may include electrical connection or coupling.

[0041] In this application, those of ordinary skill in the art will understand that relative terms used in connection with quantities or conditions (such as "about", "approximately", "substantially", etc.) are intended to include the stated 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 caused by manufacturing, assembly, use, etc. associated with a particular value. Such terms should also be considered to disclose a range defined by the absolute values of two endpoints. The 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 without the use of relative terms should also be disclosed as specific values with 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) based on the indicated angle.

[0042] In this application, those of ordinary skill in the art will understand that the functions performed by components can be performed by one component, multiple components, one part, or multiple parts. Similarly, the functions performed by parts can also be performed by one part, one component, or a combination of multiple parts.

[0043] In this application, the orientation 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 a limitation on 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 the orientation terms such as the upper side, lower side, left side, right side, front side, rear side, etc. not only represent the positive orientation, but can also be understood as the side orientation. For example, the lower side can include directly below, lower left, lower right, lower front, and lower rear, etc.

[0044] Embodiment 1

[0045] Existing blade-shaped battery cells generally adopt a structural design with pole tabs on both sides, so the positive pole column and the negative pole column are respectively arranged on the cover plates at both ends. At the position of the pole column, due to the pressing and fixing of the pole column, the first plastic part at this position will not move or be displaced. However, there is no additional limiting structure or the limiting structure design is unreasonable on the other side of the first plastic part far from the pole column, resulting in frequent skewing of the cover plate first plastic part, non-coincidence of the center lines at both ends, deformation and displacement of the first plastic part. During the use of the battery cell, problems such as poor hot-melt insulating film, scratching of the cover plate or the pole group during shell insertion, tearing of the pole tabs, abnormal peripheral welding and helium detection will also occur, which has a great impact on the yield and efficiency of the battery cell manufacturing process. At the same time, the battery cell also has a large potential safety risk.

[0046] Therefore, this embodiment provides a top cover structure to prevent the first plastic part from being skewed, deformed, or displaced, thereby improving the yield and efficiency of the battery cell manufacturing process.

[0047] like Figures 1 - 3 As shown, the top cover structure 100 of this embodiment includes a cover plate 1 and a first plastic part 2. The first plastic part 2 is attached to the side of the cover plate 1 facing the inside of the battery. The cover plate 1 is provided with a first positioning structure 11. The first plastic part 2 is provided with a pole through hole and a second positioning structure. The first positioning structure 11 and the second positioning structure cooperate with each other to limit the relative position of the first plastic part 2 and the cover plate 1, so as to prevent the first plastic part 2 from shifting at the second positioning structure of the first plastic part 2. The second positioning structure includes M groups of positioning parts 21. Along the length direction of the first plastic part 2, starting from the center of the pole through hole, a group of positioning parts 21 is provided at intervals of a preset length W. The preset length W satisfies, , M is a positive integer. That is, according to the length of the first plastic part 2, the value of M can be 1, 2, 3, 4, 5, 6 or other positive integers, and one, two, three, four, five, six or more groups of positioning parts 21 can be set.

[0048] By rationally designing the position of the second positioning structure, it can be ensured that the end of the first plastic part 2 away from the pole through hole will not be displaced or deformed, thereby avoiding problems such as defective hot-melt insulating film 400, scratching of the cover plate 1 or the pole group 300 during shell entry, tearing of the pole ear, peripheral welding and helium inspection abnormalities, thereby improving the yield and efficiency of the battery cell process.

[0049] Optionally, the first positioning structure 11 is a groove structure, and the second positioning structure is a protrusion structure. That is, a groove is provided on the side of the cover plate 1 facing the first plastic part 2, and a protrusion is provided on the side of the first plastic part 2 facing the cover plate 1. Of course, in other embodiments, a protrusion may be provided on the cover plate 1, and a groove may be provided on the first plastic part 2. In other embodiments, the first positioning structure 11 of the cover plate 1 is partially configured as a protrusion and partially configured as a groove, and correspondingly, the second positioning structure of the first plastic part 2 is partially configured as a groove and partially configured as a protrusion.

[0050] Optionally, when the width L of the first plastic part 2 is less than 20 mm, each group of positioning portions 21 includes one positioning portion 21 along the width direction of the first plastic part 2 . Only one positioning portion 21 is provided to ensure good positioning effects at various locations along the width direction of the first plastic part 2 .

[0051] Optionally, the width H of the positioning portion 21 satisfies, , to ensure the positioning effect of the positioning portion 21. Optionally, the width H of each positioning portion 21 and the width L of the first plastic part 2 meet, When the width of the positioning portion 21 is too small compared to the width of the first plastic part 2, the positioning effect is poor. When the width of the positioning portion 21 is too large compared to the width of the first plastic part 2, it will affect the structural strength of the cover plate 1 at the position corresponding to the positioning portion 21.

[0052] Optionally, the center of the positioning portion 21 is located on the center line in the width direction of the first plastic part 2 to ensure the force balance along the width direction of the first plastic part 2.

[0053] Optionally, the pole through-hole is arranged close to the first end of the first plastic part 2 along the length direction. The second end of the first plastic part 2 is arranged opposite to the first end. The value of M is 1. The positioning portion 21 is located between the pole through-hole and the second end. The distance W2 between the center of the positioning portion 21 and the second end satisfies the preset length W, . That is, when only one set of positioning portions 21 is provided, the positioning portion 21 is closer to the second end to ensure that the second end does not shift or the like.

[0054] As shown in Table 1 below, the six comparative examples are respectively six sizes of the top cover structure 100. And each of the six top cover structures 100 is provided with a positioning portion 21 on the first plastic part 2, and a corresponding groove is provided on the cover plate 1.

[0055] For the top cover structure 100 of Comparative Example 1, the preset length W is less than 60 mm, and the value of is greater than 0.38, that is, the positioning portion 21 is too close to the pole through-hole and is slightly farther from the second end of the first plastic part 2. After testing, there is a slight relative skew and eccentricity defect at the end of the second end of the first plastic part 2 of the cover plate 1 and the first plastic part 2 of this top cover structure 100. The production line yield of this top cover structure 100 is only 98.6%.

[0056] Table 1

[0057]

[0058] For the top cover structure 100 of Comparative Example 2, the value of further increases. After testing, there are relative skew and eccentricity defects at the end of the second end of the first plastic part 2 of the cover plate 1 and the first plastic part 2 of this size-designed top cover structure 100. The production line yield of this top cover structure 100 is further reduced to 98.4%.

[0059] The width H of the positioning portion 21 of the top cover structure 100 of Comparative Example 3 is less than 4 mm, and the ratio H / L of the width H of the positioning portion 21 to the width L of the first plastic part 2 is less than 0.2, that is, the positioning portion 21 is relatively narrow. After testing, for the top cover structure 100 with such a dimension design, there is only a slight relative skew and eccentricity defect between the cover plate 1 and the first plastic part 2 at the end of the second end of the first plastic part 2. However, the strength of the positioning portion 21 is insufficient and it is easily damaged, and the production line yield of the top cover structure 100 is further reduced to 97.4%.

[0060] The width H of the positioning portion 21 of the top cover structure 100 of Comparative Example 4 is less than 4 mm, but the ratio H / L of the width H of the positioning portion 21 to the width L of the first plastic part 2 is greater than 0.2, that is, the positioning portion 21 is relatively narrow, but the proportion is still appropriate. After testing, for the top cover structure 100 with such a dimension design, there is no relative skew and eccentricity defect between the cover plate 1 and the first plastic part 2 at the end of the second end of the first plastic part 2. However, the strength of the positioning portion 21 is still insufficient and it is easily damaged, and the production line yield of the top cover structure 100 can reach 98.3%.

[0061] The width H of the positioning portion 21 of the top cover structure 100 of Comparative Example 5 is greater than 4 mm, but the ratio H / L of the width H of the positioning portion 21 to the width L of the first plastic part 2 is greater than 0.5, that is, the positioning portion 21 is too wide relative to the first plastic part 2. After testing, for the top cover structure 100 with such a dimension design, there is no relative skew and eccentricity defect between the cover plate 1 and the first plastic part 2 at the end of the second end of the first plastic part 2. However, the corresponding groove on the cover plate 1 is set too wide, affecting the strength and flatness of the cover plate 1, and the production line yield of the top cover structure 100 can reach 98.6%.

[0062] For Comparative Example 6, the preset length W of the top cover structure 100 is greater than 100 mm, and the value of is greater than 0.38, that is, the distance between the pole through-hole of the top cover structure 100 and the second end is 170 mm. Only setting a group of positioning portions 21 may not be able to meet the positioning requirements within a relatively long dimension range. After testing, for the top cover structure 100 with such a dimension design, there are obvious relative skew and eccentricity defects between the cover plate 1 and the first plastic part 2 at the end of the second end of the first plastic part 2, and the production line yield of the top cover structure 100 is only 97.7%.

[0063] As shown in Table 1 above, the six examples are six top cover structures 100 of different sizes, and each of the six top cover structures 100 is provided with a positioning portion 21 on the first plastic part 2, and a corresponding groove is provided on the cover plate 1.

[0064] The values of the preset length W of Example 1, Example 2, Example 3, Example 4, Example 5 and Example 6 are all in the range of 60 mm - 100 mm, and The values are all less than 0.38, the width H of the positioning part 21 is all greater than or equal to 4 mm, and the value range of the ratio H / L of the width H of the positioning part 21 to the width L of the first plastic part 2 is greater than or equal to 0.2 and less than 0.5. After testing, there are no problems such as relative skew, bending, and eccentricity between the cover plate 1 and the first plastic part 2 in Example 1, Example 2, Example 3, Example 4, Example 5, and Example 6. The trial installation of the battery core is normal, and the production line yield is greater than 99%. It can be seen that the top cover structure 100 that meets the above size requirements can significantly improve the yield of the battery core manufacturing process, and does not require additional adjustment processes, which can greatly improve production efficiency.

[0065] Optionally, the top cover structure 100 further includes a riveting block 3, an upper plastic 4, a sealing ring 5, and a pole column 6. One end of the pole column 6 is located on the side of the cover plate 1 facing the inside of the battery, and the other end extends out of the cover plate 1 and is riveted to the riveting block 3. The upper plastic 4 is arranged between the riveting block 3 and the cover plate 1. The sealing ring 5 is sleeved on the pole column 6, and part of it is located between the cover plate 1 and the first plastic part 2, and part of it is located between the pole column 6 and the inner wall of the through hole of the cover plate 1.

[0066] Of course, in other embodiments, the pole column assembly of the top cover structure 100 may not be provided with a riveting block 3, but directly process the end of the pole column 6 to form a riveting fixed edge of the pole column 6, which can also ensure the firm positioning of the pole column 6. In some other embodiments, the end of the pole column 6 may also be fixed in the form of encapsulation, or a redundant bendable structure may be provided on the cover plate 1. After inserting the pole column 6, the bendable structure is bent to form a fixed bending edge for the pole column 6, which can also achieve the fixation of the pole column 6.

[0067] The top cover structure 100 solves the problem of relative skew of the first plastic part 2 by providing a concave-convex matching structure on the cover plate 1 and the first plastic part 2. By reasonably designing the position of the second positioning structure, it can ensure that the end of the first plastic part 2 far from the pole column through hole does not have problems such as displacement and deformation, thereby avoiding problems such as poor hot-melt insulating film 400, scratching the cover plate 1 or the pole group 300 during shell insertion, pole ear tearing, abnormal peripheral welding and helium detection, and improving the yield and efficiency of the battery core manufacturing process. The concave-convex matching structure on the cover plate 1 and the first plastic part 2 is formed by a mature process, which can reduce production costs. This embodiment also provides the relevant dimension design of the above concave-convex matching structure, which can prevent the battery core from being defective due to unreasonable design positioning. Standardizing the positioning structure design can increase the structural strength and safety performance of the cover plate 1, improve the stability of the battery core, and further improve the manufacturing process yield and automated production efficiency.

[0068] Embodiment 2

[0069] This embodiment discloses a top cover structure 100. The difference between the top cover structure 100 in this embodiment and the top cover structure 100 in Embodiment 1 is that as Figures 4 - 5As shown, optionally, when the width L of the first plastic part 2 is greater than or equal to 20 mm, along the width direction of the first plastic part 2, each group of positioning parts 21 includes two positioning parts 21 arranged at intervals.

[0070] Optionally, the distance W1 between the centers of the two positioning parts 21 in each group satisfies , to prevent the distance between the two positioning parts 21 from being too close.

[0071] Optionally, the distance W1 between the centers of the two positioning parts 21 in each group and the width L of the first plastic part 2 satisfy . If the above ratio is too small, that is, the distance between the two positioning parts 21 is too close, the edge area of the first plastic part 2 along the width direction cannot be fixed. If the above ratio is too large, that is, the two positioning parts 21 are too close to the edge, correspondingly, the grooves on the cover plate 1 will also be too close to the edge, which will affect the structural strength of the cover plate 1.

[0072] Optionally, the width H of each positioning part 21 satisfies . When the positioning part 21 is too narrow, the positioning effect is poor.

[0073] Optionally, the two positioning parts 21 in each group are symmetrically arranged along the midline in the width direction of the first plastic part 2. To ensure that along the width direction of the first plastic part 2, the positioning effect of the positioning parts 21 on each part is relatively balanced.

[0074] As shown in Table II below, the six comparative examples are six types of top cover structures 100 with different sizes. And in all six top cover structures 100, a group of positioning parts 21 are arranged on the first plastic part 2, and this group of positioning parts 21 includes two positioning parts 21 arranged at intervals along the width direction of the first plastic part 2. Correspondingly, two grooves are arranged on the cover plate 1.

[0075] For the top cover structure 100 of Comparative Example 1, the preset length W is less than 60 mm, and the value of is greater than 0.38, that is, the two positioning parts 21 are too close to the pole through hole and are slightly farther from the second end of the first plastic part 2. After testing, there is a slight relative skew and eccentricity defect at the end of the second end of the cover plate 1 and the first plastic part 2 of this top cover structure 100. The production line yield of this top cover structure 100 reaches 98.7%.

[0076] Table II

[0077]

[0078] For the top cover structure 100 of Comparative Example 2, When the value of increases further, through testing, for the cover plate 1 and the first plastic part 2 of the top cover structure 100 with this size design, there are phenomena of relative skew and eccentricity defects at the end of the second end of the first plastic part 2, and the production line yield of the top cover structure 100 is further reduced to 98.5%.

[0079] For the top cover structure 100 of Comparative Example 3 The value of is greater than 0.8, that is, the distance between the two positioning parts 21 is too large and too close to the two side edges of the first plastic part 2. Through testing, for the cover plate 1 and the first plastic part 2 of the top cover structure 100 with this size design, there are no phenomena of relative skew and eccentricity defects at the end of the second end of the first plastic part 2, but the two grooves on the cover plate 1 are too close to the two side edges of the cover plate 1, resulting in weakened side strength of the cover plate 1, prone to flatness defects, and increasing the gap between the first plastic part 2 and the cover plate 1. The production line yield of the top cover structure 100 is further reduced to 98.2%.

[0080] For the top cover structures 100 of Comparative Example 4 and Comparative Example 5 The values of are both less than 0.5, that is, the two positioning parts 21 are too close to the center line of the first plastic part 2, which will weaken the positioning effect. Through testing, for the cover plate 1 and the first plastic part 2 of the top cover structure 100 with this size design, there are slight relative skew and eccentricity defects at the end of the second end of the first plastic part 2. The production line yields of the top cover structure 100 are 98.4% and 98.6% respectively.

[0081] For the top cover structure 100 of Comparative Example 6, the preset length W is greater than 100 mm, and The value of is greater than 0.38, that is, the distance between the pole through hole of the top cover structure 100 and the second end is 170 mm. Only setting a group of positioning parts 21 may not be able to meet the positioning requirements within a longer size range. Through testing, there are obvious relative skew and eccentricity defects at the end of the second end of the first plastic part 2 of the top cover structure 100, and the production line yield of the top cover structure 100 is only 97.9%.

[0082] As shown in Table 2 above, the four examples are four top cover structures 100 of different sizes. All four top cover structures 100 are provided with a group of positioning parts 21 on the first plastic part 2, and this group of positioning parts 21 includes two positioning parts 21 arranged at intervals along the width direction of the first plastic part 2. Two corresponding grooves are provided on the cover plate 1.

[0083] The values of the preset length W of Example 1, Example 2, Example 3 and Example 4 are all within the range of 60 mm - 100 mm, and The values are all less than 0.38, the distance W1 between the centers of the two positioning parts 21 is greater than or equal to 6 mm, and the ratio of the distance W1 between the centers of the two positioning parts 21 to the width L of the first plastic part 2 is between 0.5 and 0.8. After testing, there are no problems such as relative skew, bending, and eccentricity between the cover plate 1 and the first plastic part 2 in Example 1, Example 2, Example 3, and Example 4. Moreover, the flatness of the cover plate 1 after stamping meets the requirements, the trial installation of the battery core is normal, and the production line yield is greater than 99%. It can be seen that the top cover structure 100 that meets the above size requirements can significantly improve the yield of the battery core manufacturing process, and there is no need to add adjustment processes, which can greatly improve production efficiency.

[0084] The top cover structure 100 solves the problem of relative skew of the first plastic part 2 by providing a concave-convex fitting structure on the cover plate 1 and the first plastic part 2. By reasonably designing the positions of the two positioning parts 21, it can be ensured that the end of the first plastic part 2 far from the pole column through hole does not have problems such as displacement and deformation, thereby avoiding problems such as poor hot-melt insulating film 400, scratching the cover plate 1 or the pole group 300 during shell insertion, pole ear tearing, abnormal peripheral welding and helium leak detection, and improving the yield and efficiency of the battery core manufacturing process. The concave-convex fitting structure on the cover plate 1 and the first plastic part 2 is formed by a mature process, which can reduce production costs. This embodiment also provides the relevant dimension design of the relative positions of the two positioning parts 21 when two positioning parts 21 are set in each group, which can prevent the battery core from being defective due to unreasonable positioning design. Standardizing the positioning structure design can increase the structural strength and safety performance of the cover plate 1, improve the stability of the battery core, and further improve the manufacturing process yield and automated production efficiency.

[0085] In addition, the remaining structures of the top cover structure 100 provided in this embodiment are the same as those of the top cover structure 100 in Embodiment 1, and will not be described in detail here.

[0086] Embodiment 3

[0087] This embodiment provides a battery core, as Figure 6 shown. The battery core includes a housing 200 and the top cover structure 100 in Embodiment 1 or Embodiment 2. The top cover structure 100 is hermetically arranged at the opening of the housing 200 to form a battery core outer shell.

[0088] Optionally, the battery core further includes a pole group 300 and an insulating film 400. The insulating film 400 is sleeved on the pole group 300, and both are arranged inside the battery core outer shell.

[0089] The top cover structure 100 of the battery cell solves problems such as relative skew of the first plastic part 2 by providing a concave-convex fitting structure on the cover plate 1 and the first plastic part 2. By reasonably designing the size and position of the positioning part 21, it is possible to ensure that the end of the first plastic part 2 far from the pole column through hole does not undergo displacement deformation and other problems, thereby avoiding problems such as poor hot-melt insulating film 400, scratching the cover plate 1 or the pole group 300 during shell insertion, pole ear tearing, abnormal peripheral welding and helium leak detection, and can also ensure that the flatness of the cover plate is not affected, overall improving the yield and efficiency of the battery cell manufacturing process.

[0090] The concave-convex fitting structure on the cover plate 1 and the first plastic part 2 is formed by a mature process, which can reduce production costs. By reasonably designing the size of the top cover structure, the size and relative position of the positioning part 21, it is possible to prevent defects in the battery cell caused by unreasonable design positioning. Standardizing the design of the positioning structure can increase the structural strength and safety performance of the cover plate 1, improve the stability of the battery cell, and further improve the manufacturing yield and automated production efficiency.

[0091] This embodiment also provides a battery module, including a battery housing and at least one of the above-mentioned battery cells, and at least one battery cell is arranged in the battery housing. When multiple battery cells are provided, the multiple battery cells can be set in series, parallel or series-parallel forms according to the specifications of the battery module.

[0092] This battery module can improve the yield and efficiency of the battery cell manufacturing process, reduce production costs, and improve the quality and use stability of the battery module.

[0093] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly explaining the present invention, and are not 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 list all the implementation manners here. Any modifications, equivalent replacements, and improvements 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. The top cover structure is characterized in that: The battery comprises a cover plate (1) and a first plastic part (2), wherein the first plastic part (2) is attached to a side of the cover plate (1) facing the inside of the battery, the cover plate (1) is provided with a first positioning structure (11), the first plastic part (2) is provided with a pole through hole, and a second positioning structure, the first positioning structure (11) and the second positioning structure are matched in a concave-convex manner to limit the relative position of the first plastic part (2) and the cover plate (1), and the second positioning structure comprises M groups of positioning portions (21), and along the length direction of the first plastic part (2), starting from the center of the pole through hole, a group of the positioning portions (21) is provided at intervals of a preset length W, and the preset length W satisfies: , M is a positive integer; When the width L of the first plastic part (2) is less than 20 mm, along the width direction of the first plastic part (2), each group of the positioning parts (21) comprises one positioning part (21), and the width H of the positioning part (21) satisfies: , the width H of each positioning portion (21) and the width L of the first plastic part (2) satisfy, ; When the width L of the first plastic part (2) is greater than or equal to 20 mm, along the width direction of the first plastic part (2), each group of the positioning portions (21) comprises two positioning portions (21) arranged at intervals, and the distance W1 between the centers of the two positioning portions (21) of each group satisfies: , the distance W1 between the centers of the two positioning portions (21) of each group and the width L of the first plastic part (2) satisfy, ; The pole through hole is arranged near the first end of the first plastic part (2) along the length direction, the second end of the first plastic part (2) is arranged opposite to the first end, the value of M is 1, the positioning portion (21) is located between the pole through hole and the second end, and the distance W2 between the center of the positioning portion (21) and the second end satisfies the preset length W, .

2. The top cover structure according to claim 1, characterized in that: When the width L of the first plastic part (2) is less than 20 mm, the center of the positioning portion (21) is located on the midline of the first plastic part (2) in the width direction.

3. The top cover structure according to claim 1, characterized in that: When the width L of the first plastic part (2) is greater than or equal to 20 mm, the width H of each positioning portion (21) satisfies: .

4. The top cover structure according to claim 1, characterized in that: When the width L of the first plastic part (2) is greater than or equal to 20 mm, the two positioning portions (21) in each group are symmetrically arranged along the midline of the width direction of the first plastic part (2).

5. A battery cell, characterized in that: It comprises a shell (200) and a top cover structure according to any one of claims 1 to 4, wherein the top cover structure (100) is sealed at an opening of the shell (200) to form a battery cell housing.

6. A battery module, characterized in that: The invention comprises a battery casing and at least one battery cell as claimed in claim 5, wherein the at least one battery cell is arranged in the battery casing.

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