Riveted structure and battery cover

Abstract

The present application relates to the technical field of lithium batteries, and in particular to a riveting structure and a battery cover. The riveting structure includes a riveting block and a pole; the pole includes a first column section and a second column section connected to each other, the pole has a first end and a second end arranged opposite to each other in a first direction, the first column section is arranged at the first end, and the second column section is arranged at the second end; the cross-sectional area of ​​the second column section is larger than the cross-sectional area of ​​the first column section, so as to form a step surface at the connection between the first column section and the second column section; the step surface is an annular conical surface, and in the direction from the outer edge of the annular conical surface to the inner edge, the annular conical surface gradually tilts away from the first end; the riveting block includes a riveting hole, the first column section cooperates with the riveting hole, and the riveting block contacts the annular conical surface. The riveting structure and battery cover of the present application solve the problem that in the existing riveting process, the riveting block and the pole are prone to poor contact, resulting in a gap, which in turn causes the internal resistance of the cover plate to increase, affecting the overall performance of the single cell.

Description

Technical Field

[0001] The present application relates to the technical field of lithium batteries, and in particular to a riveting structure and a battery cover. Background Art

[0002] As lithium-ion battery technology matures, lithium-ion batteries are widely used as power batteries in the field of electric vehicles. The cover of lithium-ion batteries is also an important component of lithium-ion power batteries. It not only provides protection for lithium-ion batteries in terms of safety and reliability, but also takes into account the connection between the internal chemical system of lithium-ion batteries and external modules.

[0003] The most widely used and largest number of battery covers are mainly riveted structures. The riveting process mainly involves processing each part of the cover separately, and then riveting the parts together through rivet punching to achieve sealing, insulation and other requirements.

[0004] However, in the riveting process, since the riveting force is from top to bottom along the vertical direction of the center of the pole, this will cause the center area of ​​the pole to be relatively concave, and the four corners of the edge of the rivet block will be lifted up by the reaction force, which will lead to poor contact between the rivet block and the pole, resulting in a gap, which will increase the internal resistance of the cover plate, affect the overall performance of the single cell, and is not conducive to improving the fast charging capability of the single cell. It is also difficult to meet the needs of high-rate batteries. Summary of the invention

[0005] The purpose of the present application is to provide a riveted structure and a battery cover plate, thereby solving the problem in the existing riveting process that the riveted block and the pole are prone to poor contact, resulting in gaps, which in turn leads to increased internal resistance of the cover plate and affects the overall performance of the single cell.

[0006] According to a first aspect of the present application, a riveted structure is provided, the riveted structure comprising a riveting block and a pole; the pole comprises a first column segment and a second column segment connected to each other, the pole having a first end and a second end arranged opposite to each other in a first direction, the first column segment being arranged at the first end, and the second column segment being arranged at the second end; the cross-sectional area of ​​the second column segment is larger than the cross-sectional area of ​​the first column segment, so as to form a step surface at the connection between the first column segment and the second column segment; the step surface is an annular conical surface, and in the direction in which the outer edge of the annular conical surface points to the inner edge, the annular conical surface gradually inclines in a direction away from the first end; the riveted block comprises a riveting hole, the first column segment cooperates with the riveting hole, and the bottom surface of the riveted block contacts the annular conical surface.

[0007] In any of the above technical solutions, further, the first column segment and the second column segment are both cylindrical.

[0008] In any of the above technical solutions, further, ;

[0009] Wherein, h is the height of the annular cone in the first direction, The complementary angle of the cone angle of the annular cone surface, b is the diameter of the second column segment, and a is the diameter of the riveting hole.

[0010] In any of the above technical solutions, further, a height h of the annular cone in the first direction is 0.1 mm to 1.4 mm.

[0011] In any of the above technical solutions, further, the complementary angle of the cone angle of the annular cone is 5° to 45°.

[0012] In any of the above technical solutions, further, the complementary angle of the cone angle of the annular cone is 10° to 30°.

[0013] In any of the above technical solutions, further, the diameter b of the second column segment is 5 mm to 50 mm.

[0014] In any of the above technical solutions, further, the diameter a of the riveting hole is 4 mm to 45 mm.

[0015] According to a second aspect of the present application, a battery cover is provided, and the battery cover includes the riveting structure as described above.

[0016] In any of the above technical solutions, further, the battery cover plate also includes a first plastic part, a top cover sheet and a second plastic part; the pole also includes a base, and the second column segment is connected between the first column segment and the base; the pole passes through the second plastic part, the top cover sheet, the first plastic part and the riveting block in sequence; wherein the first column segment of the pole cooperates with the riveting hole of the riveting block, the second column segment of the pole cooperates with the through holes of the first plastic part, the top cover sheet and the second plastic part, and the base of the pole fits the bottom surface of the second plastic part.

[0017] The riveting structure of the present application includes a riveting block and a pole; wherein the pole includes a first pole section and a second pole section connected to each other, the pole has a first end and a second end arranged opposite to each other in a first direction, the first pole section is arranged at the first end, and the second pole section is arranged at the second end; the cross-sectional area of ​​the second pole section is larger than the cross-sectional area of ​​the first pole section, so as to form a step surface at the connection between the first pole section and the second pole section; the step surface is an annular conical surface, and in the direction from the outer edge of the annular conical surface to the inner edge, the annular conical surface gradually tilts in the direction away from the first end; the riveting block includes a riveting hole, the first pole section cooperates with the riveting hole, and the riveting block contacts the annular conical surface.

[0018] According to the above technical features, the beneficial effects of this application are:

[0019] The pole of the present application is provided with an annular conical surface at the position in contact with the bottom surface of the riveted block. When the pole and the riveted block are assembled by riveting, the annular conical surface above the pole will always be in close contact with the bottom surface of the riveted block under pressure, so that the riveted block and the pole are more tightly connected. In other words, the annular conical surface surrounds the center of the pole, and the height gradually increases from the center to the outside. When the pole and the riveted block are assembled by riveting, the annular conical surface can compensate for the gap between the riveted block that is tilted upward and the pole.

[0020] Thus, compared with the prior art, after the pole and the riveted block are assembled by riveting, the riveted block and the pole are more tightly connected to ensure the internal resistance of the entire cover plate.

[0021] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A cross-sectional schematic diagram of a riveted structure after riveting according to an embodiment of the present application is shown;

[0024] Figure 2 A cross-sectional schematic diagram of a riveting block according to an embodiment of the present application is shown;

[0025] Figure 3 A schematic cross-sectional view showing a portion of a pole before riveting according to an embodiment of the present application;

[0026] Figure 4 Show Figure 3 Schematic diagram of the enlarged structure of the Z part;

[0027] Figure 5 A top view of a battery cover according to an embodiment of the present application is shown;

[0028] Figure 6 Show Figure 5 Schematic diagram of the AA cross-section structure.

[0029] Icon: 101-first column section; 102-second column section; 103-base; 104-annular cone; 200-rivet block; 201-rivet hole; 202-bottom surface; 300-first plastic part; 400-top cover piece; 500-second plastic part; L1-first direction. DETAILED DESCRIPTION

[0030] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be apparent. For example, the order of operations described herein is merely an example, and is not limited to the order set forth herein, but in addition to the operations that must occur in a particular order, changes that will be apparent after understanding the disclosure of the present application may be made. In addition, in order to improve clarity and brevity, descriptions of features known in the art may be omitted.

[0031] The features described herein may be implemented in different forms and should not be interpreted as being limited to the examples described herein. Rather, the examples described herein have been provided only to illustrate some of the many possible ways of implementing the methods, devices and / or systems described herein that will be apparent after understanding the disclosure of the present application.

[0032] Throughout the specification, when an element (such as a layer, a region, or a substrate) is described as being “on”, “connected to”, “bound to”, “over”, or “covering” another element, it may be directly “on”, “connected to”, “bound to”, “over”, or “covering” another element, or one or more other elements may be present between them. In contrast, when an element is described as being “directly on”, “directly connected to”, “directly bound to”, “directly over”, or “directly covering” another element, there may be no other elements present between them.

[0033] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more items.

[0034] Although terms such as "first," "second," and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions are not limited by these terms. Rather, these terms are only used to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Therefore, without departing from the teachings of the examples described herein, the first member, component, region, layer, or portion referred to may also be referred to as the second member, component, region, layer, or portion.

[0035] For ease of description, spatial relational terms such as "above", "upper", "below", and "lower" may be used herein to describe the relationship of one element to another element as shown in the accompanying drawings. Such spatial relational terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. For example, if the device in the accompanying drawings is turned over, an element described as being "above" or "upper" relative to another element will subsequently be "below" or "lower" relative to the other element. Therefore, the term "above" includes both "above" and "below" orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relational terms used herein will be interpreted accordingly.

[0036] The terms used herein are only used to describe various examples and are not used to limit the present disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "include", "comprise" and "have" list the stated features, quantities, operations, components, elements and / or their combinations that exist, but do not exclude the existence or addition of one or more other features, quantities, operations, components, elements and / or their combinations.

[0037] Variations in the shapes shown in the drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings but include variations in shapes that occur during manufacturing.

[0038] The features of the examples described herein may be combined in various ways that will be apparent after understanding the disclosure of the present application. In addition, although the examples described herein have various configurations, other configurations are possible as will be apparent after understanding the disclosure of the present application.

[0039] During the riveting process, since the riveting force is from top to bottom along the vertical direction of the center of the pole, this will cause the center area of ​​the pole to be relatively concave, and the four corners of the edge of the rivet block will be lifted up by the reaction force, which will lead to poor contact between the rivet block and the pole, resulting in a gap, causing the internal resistance of the cover plate to increase, affecting the overall performance of the single cell, which is not conducive to improving the fast charging capability of the single cell, and is not easy to meet the needs of high-rate batteries.

[0040] In view of this, according to the first aspect of the present application, a riveting structure is provided to solve the problem in the existing riveting process that the riveting block and the pole are prone to poor contact, resulting in a gap, which in turn causes the internal resistance of the cover plate to increase, affecting the overall performance of the single cell.

[0041] The following will refer to Figures 1 to 4 The riveted structure according to some embodiments of the present application is described.

[0042] like Figures 1 to 3 As shown, the riveting structure of the present application includes a riveting block 200 and a pole; wherein the pole includes a first pole segment 101 and a second pole segment 102 connected to each other, and the pole has a first end and a second end arranged opposite to each other in a first direction L1, the first pole segment 101 is arranged at the first end, and the second pole segment 102 is arranged at the second end; the cross-sectional area of ​​the second pole segment 102 is larger than the cross-sectional area of ​​the first pole segment, so as to form a step surface at the connection between the first pole segment 101 and the second pole segment 102; the step surface is an annular conical surface 104, and in the direction from the outer edge of the annular conical surface 104 to the inner edge, the annular conical surface 104 gradually tilts away from the first end (see Figure 3 ); The riveting block 200 includes a riveting hole 201, the first column segment 101 cooperates with the riveting hole 201, and the riveting block 200 contacts the annular cone surface 104.

[0043] That is, the pole of the present application is provided with an annular conical surface 104 at the position in contact with the bottom surface 202 of the riveted block 200. When the pole and the riveted block 200 are assembled by riveting, the annular conical surface 104 above the pole will always be in close contact with the bottom surface 202 of the riveted block 200 under pressure, so that the riveted block 200 and the pole are more tightly connected. That is, the annular conical surface 104 surrounds the center of the pole, and the height gradually increases from the center to the outside. When the pole and the riveted block 200 are assembled by riveting, the annular conical surface 104 can compensate for the gap between the riveted block 200 that is upwardly tilted and the pole.

[0044] In this way, compared with the prior art, after the pole and the rivet block are assembled by riveting and pressing, the rivet block and the pole are more tightly connected to ensure the overall internal resistance of the cover plate, thereby improving the overall performance of the single cell, improving the fast charging capability of the single cell, and meeting the needs of high-rate batteries.

[0045] It should be noted that Figure 3 The figure shows a cross-sectional view of a portion of the pole before riveting. Figure 3 The structure of the annular cone 104 is shown in FIG. Figure 3 The size of the annular cone 104 is enlarged. In the actual process, the size of the annular cone 104 is not Figure 3 As big as shown in the figure.

[0046] In the embodiment of the present application, the first column segment 101 and the second column segment 102 may both be cylindrical, and the annular cone surface 104 is a circular annular cone surface.

[0047] In the embodiments of the present application, Figure 4 As shown, the height h of the annular conical surface 104 in the first direction L1 is preferably 0.1 mm to 1.4 mm.

[0048] If the height h is too large and is higher than 1.4 mm, the riveting effect will be affected, because too large a height h will cause the riveting block 200 to lift too much, thereby affecting the subsequent welding of the single cell and the busbar. If the height h is too small and is lower than 0.1 mm, no compensation effect can be achieved.

[0049] Therefore, when the height h is 0.1 mm to 1.4 mm, the riveting effect of the pole and the riveting block 200 is the best. When the pole and the riveting block 200 are assembled by riveting, the annular conical surface 104 can not only compensate for the gap between the riveting block 200 and the pole, so that the riveting block 200 and the pole are more tightly connected; and the height h will not be too large to cause the riveting block 200 to be tilted too much.

[0050] In the embodiments of the present application, Figure 3 As shown, the diameter b of the second column section 102 may be 5 mm to 50 mm. Figure 2 As shown, the diameter a of the rivet hole 201 may be 4 mm to 45 mm.

[0051] Thus, the diameter b of the second pole section 102 of the pole is 5 mm to 50 mm, and the diameter a of the riveting hole 201 is 4 mm to 45 mm, which can be applicable to most cover plate sizes.

[0052] In order to compensate for the gap difference caused by different sizes of poles, this application designs .like Figure 4 As shown, where h is the height of the annular cone 104 in the first direction L1, The complementary angle of the cone angle of the annular cone surface 104 is that b is the diameter of the second column segment 102 , and a is the diameter of the riveting hole 201 .

[0053] In this way, according to the diameter b of the second column section 102 and the diameter a of the rivet hole 201, , the height h and the complementary angle of the cone angle of the annular cone 104 are obtained It is preferred to ensure that the height h of the annular conical surface 104 in the first direction L1 is 0.1 mm to 1.4 mm.

[0054] Furthermore, in the embodiment of the present application, the complementary angle of the cone angle of the annular cone surface 104 is The effect is better if the angle is 5° to 45°. If the angle is too large, it will cause the cover plate to be unable to be properly positioned during assembly, affecting the closing of the riveting mold and causing the riveting to fail. If it is too small, less than 5°, it will not be effective in compensating the gap of the riveting.

[0055] The larger the diameter b of the second column section 102 of the pole is, the greater the angle The complementary angle of the cone angle of the annular cone surface 104 should also be increased accordingly to ensure better assembly processability. A more preferred range is 10° to 30°. When the angle is between 10° and 30°, the riveting effect of the pole and the riveting block is the best. After the pole and the riveting block are assembled by riveting, the annular cone surface can not only compensate for the gap between the riveting block and the pole, making the riveting block and the pole more tightly connected; but also the angle If it is too large, the cover cannot be positioned properly during assembly.

[0056] In order to verify the design effect, different single cells were arranged for verification, and the results are shown in the following table.

[0057] Table 1:

[0058]

[0059] Table 2:

[0060]

[0061] Table 3:

[0062]

[0063] It can be seen that in order to compensate for the gap difference caused by different sizes of poles, the present application can be based on Make adjustments.

[0064] According to a second aspect of the present application, a battery cover is provided, and the battery cover includes the riveting structure as described above.

[0065] The riveting structure of the present application is applicable to all battery cover plates mainly using riveting structures.

[0066] As an example, Figure 5 and Figure 6As shown, the battery cover also includes a first plastic part 300, a top cover sheet 400 and a second plastic part 500; Figure 1 and Figure 3 As shown, the pole also includes a base 103, and the second column section 102 is connected between the first column section 101 and the base 103; wherein the pole passes through the second plastic part 500, the top cover sheet 400, the first plastic part 300 and the riveting block 200 in sequence; wherein the first column section 101 of the pole cooperates with the riveting hole 201 of the riveting block 200, and the second column section 102 of the pole cooperates with the through holes of the first plastic part 300, the top cover sheet 400 and the second plastic part 500, and the base 103 of the pole fits the bottom surface of the second plastic part 500.

[0067] In summary, the pole of the present application is provided with an annular conical surface at the position in contact with the bottom surface of the riveted block. When the pole and the riveted block are assembled by riveting, the annular conical surface above the pole will always be in close contact with the bottom surface of the riveted block under pressure, so that the riveted block and the pole are more tightly connected. In other words, the annular conical surface surrounds the center of the pole, and the height gradually increases from the center to the outside. When the pole and the riveted block are assembled by riveting, the annular conical surface can compensate for the gap between the riveted block that is tilted upward and the pole.

[0068] In this way, compared with the prior art, after the pole and the rivet block are assembled by riveting, the rivet block and the pole are more tightly connected to ensure that the overall internal resistance of the cover plate is less than 0.05mΩ, thereby improving the overall performance of the single cell battery, improving the fast charging capability of the single cell battery, and meeting the needs of high-rate batteries.

[0069] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that any technician familiar with this technical field can still modify the technical solutions recorded in the aforementioned embodiments within the technical scope disclosed in the present application, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be covered by the protection scope of the present application.

Claims

1. A riveted structure, characterized in that: The riveted structure comprises a riveted block and a pole; The pole comprises a first pole section and a second pole section connected to each other, the pole has a first end and a second end arranged opposite to each other in a first direction, the first pole section is arranged at the first end, and the second pole section is arranged at the second end; The cross-sectional area of ​​the second column segment is greater than the cross-sectional area of ​​the first column segment, so as to form a step surface at the connection between the first column segment and the second column segment; The step surface is an annular conical surface, and in the direction from the outer edge of the annular conical surface to the inner edge, the annular conical surface gradually inclines in the direction away from the first end; The riveting block comprises a riveting hole, the first column section cooperates with the riveting hole, and the bottom surface of the riveting block contacts the annular conical surface; when the pole and the riveting block are assembled by riveting, the annular conical surface can compensate for the gap between the riveting block that is upwardly tilted and the pole; ; wherein h is the height of the annular cone in the first direction, The complementary angle of the cone angle of the annular cone surface, b is the diameter of the second column segment, and a is the diameter of the riveting hole; The height h of the annular cone in the first direction is 0.1 mm to 1.4 mm; The complementary angle of the cone angle of the annular cone 5° to 45°.

2. The riveted structure according to claim 1, characterized in that: The first column section and the second column section are both cylindrical.

3. The riveted structure according to claim 1, characterized in that: The complementary angle of the cone angle of the annular cone 10° to 30°.

4. The riveted structure according to claim 1, characterized in that: The diameter b of the second column section is 5 mm to 50 mm.

5. The riveted structure according to claim 1, characterized in that: The diameter a of the riveting hole is 4 mm to 45 mm.

6. A battery cover, characterized in that: The battery cover plate includes the riveted structure as claimed in any one of claims 1 to 5.

7. The battery cover according to claim 6, characterized in that: The battery cover plate also includes a first plastic part, a top cover sheet and a second plastic part; The pole also includes a base, and the second pole section is connected between the first pole section and the base; The pole passes through the second plastic part, the top cover sheet, the first plastic part and the riveting block in sequence; The first column section of the pole cooperates with the riveting hole of the riveting block, the second column section of the pole cooperates with the through holes of the first plastic part, the top cover sheet and the second plastic part, and the base of the pole fits the bottom surface of the second plastic part.

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