Lower plastic, battery cover plate and battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a lower plastic, a battery cover plate and a battery, the lower plastic comprises a plastic plate and a connecting block, the connecting block comprises a first part and a second part, the second part is fixedly connected with the plastic plate, and the first part is connected with one end, deviating from the plastic plate, of the second part. The cross-sectional area of the first part is smaller than that of the second part. Therefore, when the lower plastic and the top cover sheet are assembled, as the cross sectional area of the first part is smaller than that of the second part, the first part starts to melt firstly and is connected with the top cover sheet under the ultrasonic action, so that the melting position is more controllable, and the poor connecting effect of the connecting block and the top cover sheet after the connecting block is melted is avoided; and the connection strength of the lower plastic and the top cover plate after ultrasonic welding is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a lower plastic, a battery cover and a battery. Background Art

[0002] A battery is a device that converts chemical energy into electrical energy. Lithium batteries, as a commonly used battery, are widely used in modern electronic devices and energy storage systems.

[0003] The battery includes a battery cell, a shell and a cover plate. The cover plate is fixedly connected to the shell. The battery cell is arranged in a confined space formed by the cover plate and the shell. The cover plate includes a top cover sheet and a lower plastic. The lower plastic is arranged between the top cover sheet and the battery cell to insulate the top cover sheet to prevent the top cover sheet made of conductive material from contacting the battery cell and causing a short circuit.

[0004] In the prior art, a protrusion is provided on the surface of the lower plastic, and a groove matching the protrusion is provided on the top cover sheet. The protrusion of the lower plastic is inserted into the groove and the protrusion and the top cover sheet are connected by ultrasonic welding, so that the lower plastic and the top cover sheet can be assembled. However, since the structural strength of each part of the protrusion is uniform, it is difficult to control the melting position during ultrasonic melting. The melted protrusion may accumulate at the root position of the protrusion, making it difficult for the melted lower plastic to fill the corresponding groove, thereby reducing the connection strength between the lower plastic and the top cover sheet, making it impossible for the lower plastic and the top cover sheet to be firmly connected. Utility Model Content

[0005] The purpose of the utility model is to provide a lower plastic, a battery cover and a battery, so as to solve the problem of low connection strength when the lower plastic is connected to the top cover by ultrasonic welding.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In a first aspect, a lower plastic comprises: a plastic plate; a connecting block, the connecting block comprising a first portion and a second portion, the second portion being fixedly connected to the plastic plate, the first portion being connected to an end of the second portion facing away from the plastic plate, and the cross-sectional area of the first portion being smaller than the cross-sectional area of the second portion.

[0008] Preferably, a plurality of the connecting blocks are provided, and the plurality of connecting blocks are all provided on the side wall edge of the same side of the plastic plate.

[0009] Preferably, a plurality of the first parts are provided on one second part, the plurality of the first parts are evenly spaced and arranged at one end of the second part away from the plastic plate, and the first part is fixedly connected to the second part.

[0010] Preferably, the end surface of the first portion facing away from the second portion is provided with knurling.

[0011] Preferably, the cross-sectional area of the first portion gradually decreases from one end of the first portion toward the second portion to one end of the first portion away from the second portion.

[0012] In a second aspect, a battery cover comprises a top cover sheet and the lower plastic as described above, wherein the top cover sheet is provided with a connection groove for accommodating the connection block at a position corresponding to the connection block, and the connection block is embedded in the connection groove by ultrasonic welding.

[0013] Preferably, the top cover piece is further provided with a limiting groove, which is arranged at one end of the connecting groove away from the plastic plate. The limiting groove is communicated with the connecting groove and is used to limit the position of the connecting block after melting in the connecting groove.

[0014] Preferably, the minimum cross-sectional area of the limiting groove is not less than the minimum cross-sectional area of the connecting groove; and / or the maximum cross-sectional area of the limiting groove is not greater than the maximum cross-sectional area of the connecting groove.

[0015] Preferably, the minimum cross-sectional area of the connecting groove and the minimum cross-sectional area of the limiting groove are both larger than the maximum cross-sectional area of the connecting block.

[0016] In a third aspect, a battery comprises a shell, a battery cell and the battery cover as described above, wherein the battery cell is arranged inside the shell, and the battery cover is fixedly connected to the shell.

[0017] Beneficial effects of the utility model:

[0018] A lower plastic comprises a plastic plate and a connecting block, wherein the connecting block comprises a first part and a second part, wherein the second part is fixedly connected to the plastic plate, the first part is connected to an end of the second part facing away from the plastic plate, and the cross-sectional area of the first part is smaller than that of the second part.

[0019] In this way, when the lower plastic is assembled to the top cover piece by ultrasonic welding, since the cross-sectional area of the first part is smaller than that of the second part, the structural strength of the first part is smaller than that of the second part, and the first part starts to melt first and connects with the top cover piece, which makes it easy to control the melting position, avoids a loose connection between the connecting block and the top cover piece after melting, and improves the connection strength between the lower plastic and the top cover piece after ultrasonic welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of the lower plastic in one embodiment of the present utility model;

[0021] Figure 2 In one embodiment of the present utility model Figure 1 A magnified view of point A;

[0022] Figure 3 This is a structural diagram of a battery cover in one embodiment of the present utility model;

[0023] Figure 4 It is a cross-sectional view of a battery cover in one embodiment of the present utility model;

[0024] Figure 5 In one embodiment of the present utility model Figure 4 Enlarged view of point B.

[0025] In the picture:

[0026] 1. Plastic plate; 2. Connecting block; 21. First part; 22. Second part; 3. Top cover; 31. Connecting groove; 32. Limiting groove. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0028] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0029] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0030] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0031] Example 1

[0032] See Figure 1 and Figure 2 The utility model provides a lower plastic, including a plastic plate 1 and a connecting block 2, the connecting block 2 includes a first part 21 and a second part 22, the second part 22 is fixedly connected to the plastic plate 1, the first part 21 is connected to the end of the second part 22 away from the plastic plate 1, and the cross-sectional area of the first part 21 is smaller than the cross-sectional area of the second part 22.

[0033] In this embodiment, the second portion 22 and the plastic plate 1 are integrally formed by an injection molding process. The second portion 22 is a cylindrical structure. The length direction of the second portion 22 is perpendicular to the length direction of the plastic plate 1. The length direction of the first portion 21 is parallel to the length direction of the second portion 22, and the first portion 21 and the second portion 22 are coaxially arranged.

[0034] It should be noted that when the plastic plate 1 is assembled to the top cover sheet 3, the first part 21 is brought into contact with the top cover sheet 3, and the first part 21 is ultrasonically welded so that the first part 21 is melted and tightly connected to the top rod sheet, thereby fixing the relative positions of the plastic plate 1 and the top cover sheet 3.

[0035] In this way, when the first part 21 is ultrasonically melted, since the cross-sectional area of the first part 21 is smaller than the cross-sectional area of the second part 22, the structural strength of the first part 21 is smaller than the structural strength of the second part 22, so that the first part 21 can start to melt first and connect with the top cover sheet 3, avoiding the difficulty in controlling the melting position due to the uniform structural strength of each part of the connecting block 2, so that the connecting block 2 can be stably connected to the top cover sheet 3, and the connection strength between the lower plastic and the top cover sheet 3 after ultrasonic welding is improved.

[0036] It can be understood that the length direction of the first part 21 can also be set at an angle to the length direction of the second part 22. In this embodiment, the length direction of the first part 21 is parallel to the length direction of the second part 22 in order to facilitate the processing of the connecting block 2 and improve the processing and assembly efficiency.

[0037] See Figures 1 to 3In some embodiments, multiple connecting blocks 2 are provided, and each of the connecting blocks 2 is disposed on the same side of the sidewall edge of the plastic plate 1. In this embodiment, there are twelve connecting blocks 2, which are symmetrically arranged on the edge of the plastic plate 1 and are evenly spaced. The connecting blocks 2 are disposed on the side of the plastic plate 1 facing the top cover sheet 3 to facilitate ultrasonic welding with the top cover sheet 3.

[0038] In this way, multiple connecting blocks 2 can improve the connection strength between the lower plastic and the top cover piece 3, so that each part of the lower plastic can be evenly fixedly connected to the top cover piece 3. Multiple connecting blocks 2 are arranged at equal intervals, which can make the lower plastic evenly stressed and improve the structural strength of the lower plastic.

[0039] It is understandable that the number and location of the connecting blocks 2 can be flexibly adjusted according to the actual size of the plastic plate 1. The number of connecting blocks 2 is not limited to 12, but can also be 6, 8, 10, etc. This embodiment does not limit this.

[0040] See Figure 2 In some embodiments, a plurality of first portions 21 are disposed on a single second portion 22. The plurality of first portions 21 are evenly spaced apart at the end of the second portion 22 facing away from the plastic plate 1, and the first portion 21 is fixedly connected to the second portion 22. The projections of all first portions 21 along the lengthwise direction of the second portion 22 (i.e., along the thickness direction of the lower plastic) are located within the projections of the second portion 22 along the lengthwise direction of the second portion 22. The first portion 21 is integrally formed with the second portion 22 through an injection molding process.

[0041] In this way, multiple first parts 21 are arranged at intervals on the second part 22, which can make the structural strength of the first part 21 smaller than the structural strength of the second part 22, and when the first part 21 is melted, the molten first part 21 can flow in the space between the multiple first parts 21, avoiding accumulation at the connection between the second part 22 and the plastic plate 1 so that the first part 21 cannot be well connected to the top cover sheet 3, thereby improving the connection strength between the connecting block 2 and the top cover sheet 3, and further improving the connection strength when the lower plastic is connected to the top cover sheet 3 by ultrasonic welding.

[0042] It can be understood that the second part 22 may also be provided with a groove (not shown in the figure) that is adapted to the shape of one end of the first part 21 facing the second part 22, so that the first part 21 can be inserted into the second part 22 to achieve a detachable connection. In this embodiment, the first part 21 and the second part 22 are integrally formed, which not only facilitates the processing of the connecting block 2, but also improves the connection strength between the first part 21 and the second part 22.

[0043] See Figure 2In some embodiments, the cross-sectional area of the first portion 21 gradually decreases from one end of the first portion 21 toward the second portion 22 to the end of the first portion 21 away from the second portion 22. In this embodiment, the first portion 21 is a quadrangular pyramid with a trapezoidal longitudinal section.

[0044] In this way, the contact area between the first portion 21 and the top cover sheet 3 can be reduced, thereby reducing the structural strength of the end of the first portion 21 away from the second portion 22, so that the end of the first portion 21 in contact with the top cover sheet 3 begins to melt first and connects to the top cover sheet 3, thereby improving the structural strength of the lower plastic and the top cover sheet 3.

[0045] It is understandable that the first part 21 can also be a conical structure, or a structure with a step-wise reduction in cross-sectional area. The shape of the first part 21 can be adjusted according to the actual needs of ultrasonic welding and the specifications of the lower plastic and the top cover sheet 3, and no further details will be listed here.

[0046] See Figures 3 to 5 The present invention also provides a battery cover, including a top cover 3 and a lower plastic, the top cover 3 corresponds to the connecting block 2 (see Figure 1 ) is provided at a position thereof with a connection groove 31 for accommodating the connection block 2, and the connection block 2 is embedded in the connection groove 31 by ultrasonic welding.

[0047] In this embodiment, the length direction of the top cover sheet 3 is parallel to the length direction of the plastic plate 1. The number of connecting grooves 31 is equal to the number of connecting blocks 2, so that all connecting blocks 2 can be inserted into the connecting grooves 31 and ultrasonically welded. The connecting grooves 31 are stepped grooves, and the cross-sectional area of the end of the connecting groove 31 facing the plastic plate 1 is larger than that of the end facing away from the plastic plate 1.

[0048] In this way, the melted connecting block 2 solidifies in the connecting groove 31 , which enables the connecting block 2 to be stably connected to the top cover piece 3 , preventing the connecting block 2 from falling out of the connecting groove 31 and improving the connection strength between the lower plastic and the top cover piece 3 .

[0049] It can be understood that the connecting groove 31 can also be a straight groove. In this embodiment, the connecting groove 31 is set as a stepped groove to facilitate the assembly of the connecting block 2 into the connecting groove 31 and to limit the position of the connecting block 2 in the connecting groove 31. The shape of the connecting groove 31 can be flexibly adjusted according to actual needs, and no further examples are given here.

[0050] See Figure 1 and Figure 5In some embodiments, the top cover plate 3 further defines a limiting groove 32. The limiting groove 32 is disposed at the end of the connecting groove 31 facing away from the plastic plate 1. The limiting groove 32 communicates with the connecting groove 31 and is used to limit the position of the connecting block 2 within the connecting groove 31 after melting. When the connecting block 2 is inserted into the connecting groove 31, the connecting block 2, the limiting groove 32, and the connecting groove 31 are coaxially disposed. The combined length of the connecting groove 31 and the limiting groove 32 is less than the length of the connecting block 2.

[0051] It should be noted that the connecting block 2 is inserted into the connecting groove 31 so that the end of the first part 21 facing away from the second part 22 abuts against the inner wall of the limiting groove 32, and the connecting block 2 is ultrasonically melted. After the connecting block 2 is solidified, it exists in the limiting groove 32 and the connecting groove 31, thereby improving the connection strength between the lower plastic and the top cover piece 3.

[0052] In this way, the total length of the connecting groove 31 and the limiting groove 32 is less than the length of the connecting block 2, so that the connecting block 2 can be fully filled into the connecting groove 31 and the limiting groove 32 after ultrasonic melting, thereby improving the connection strength between the lower plastic and the top cover sheet 3 and reducing the risk of falling off caused by the inability of the connecting block 2 to fully fill the connecting groove 31 and the limiting groove 32 after melting.

[0053] See Figure 5 In some embodiments, the minimum cross-sectional area of the limiting groove 32 is not less than the minimum cross-sectional area of the connecting groove 31; and the maximum cross-sectional area of the limiting groove 32 is not greater than the maximum cross-sectional area of the connecting groove 31. In this embodiment, the limiting groove 32 is a cylindrical straight groove, and the connecting groove 31 is a cylindrical stepped groove. That is, the diameter of the limiting groove 32 is between the minimum and maximum diameters of the connecting groove 31.

[0054] In this way, since the structural strength of the first part 21 is less than the structural strength of the second part 22, the first part 21 begins to melt first and flows into the limiting groove 32. After the lower plastic and the top cover piece 3 are ultrasonically welded, since the minimum diameter of the limiting groove 32 is not less than the minimum diameter of the connecting groove 31, the connecting block 2 solidified after melting can form a barb structure, thereby avoiding the unstable connection between the connecting block 2 and the top cover piece 3 due to the accumulation of the connecting block 2 at the root position after melting, and making it difficult for the connecting block 2 to fall off from the connecting groove 31 and the limiting groove 32, thereby further improving the connection strength between the lower plastic and the top cover piece 3.

[0055] It can be understood that the minimum diameter of the limiting groove 32 can also be greater than or equal to the maximum diameter of the connecting groove 31. In this embodiment, the minimum diameter of the limiting groove 32 is smaller than the maximum diameter of the connecting groove 31. The purpose is to improve the structural strength of the top cover plate 3 where the limiting groove 32 is opened.

[0056] See Figure 1 and Figure 5In some embodiments, the minimum cross-sectional area of the connecting groove 31 and the minimum cross-sectional area of the limiting groove 32 are both larger than the maximum cross-sectional area of the connecting block 2, that is, the minimum diameter of the connecting groove 31 and the diameter of the limiting groove 32 are both larger than the diameter of the connecting block 2.

[0057] In this way, the connecting block 2 after ultrasonic melting can have sufficient flow space, so that the connecting block 2 and the top cover piece 3 after solidification in the connecting groove 31 and the limiting groove 32 are stably connected, thereby improving the connection strength between the lower plastic and the top cover piece 3 and improving the sealing performance between the lower plastic and the top cover piece 3.

[0058] See Figure 3 The present invention also provides a battery comprising a housing (not shown), a battery cell (not shown), and a battery cover. The battery cell is disposed within the housing, and the battery cover is fixedly connected to the housing. The top cover 3 is fixedly connected to the housing by welding, and a lower plastic member is disposed between the top cover 3 and the battery cell to insulate the top cover 3.

[0059] Example 2

[0060] In some embodiments, the end surface of the first part 21 facing away from the second part 22 is provided with knurling, and the first part 21 is provided with one, and the cross-sectional area of one end of the first part 21 facing the second part 22 is equal to the cross-sectional area of the second part 22, and the first part 21 and the second part 22 are integrally formed.

[0061] In this way, when assembling the lower plastic and the top cover sheet 3, the position where the knurling is set on the first part 21 is in point contact with the top cover sheet 3. The structural strength of the first part 21 is less than the structural strength of the second part 22. When the first part 21 is ultrasonically melted, the contact point between the first part 21 and the top cover sheet 3 can start to melt first, so that the first part 21 enters the limiting groove 32 after melting, thereby improving the connection strength between the lower plastic and the top cover sheet 3.

[0062] It can be understood that the end surface of the first part 21 facing away from the second part 22 is not limited to being provided with knurling, but can also be a strip-shaped protrusion or other structure, which can reduce the contact area between the end surface of the first part 21 facing away from the second part 22 and the top cover sheet 3 so that the first part 21 can be tightly combined with the top cover sheet 3 after ultrasonic melting. They are not listed here.

[0063] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A lower plastic, characterized in that, include: Plastic sheet (1); A connecting block (2), the connecting block (2) comprising a first portion (21) and a second portion (22), the second portion (22) being fixedly connected to the plastic plate (1), the first portion (21) being connected to an end of the second portion (22) facing away from the plastic plate (1), and the cross-sectional area of the first portion (21) being smaller than the cross-sectional area of the second portion (22).

2. The lower plastic according to claim 1, characterized in that: A plurality of the connecting blocks (2) are provided, and the plurality of connecting blocks (2) are all provided on the side wall edge on the same side of the plastic plate (1).

3. The lower plastic according to claim 1, characterized in that: A plurality of the first parts (21) are arranged on one of the second parts (22), and the plurality of the first parts (21) are evenly spaced and arranged at one end of the second part (22) away from the plastic plate (1), and the first part (21) and the second part (22) are fixedly connected.

4. The lower plastic according to claim 1, characterized in that: The end surface of the first portion (21) facing away from the second portion (22) is provided with knurling.

5. The lower plastic according to any one of claims 1 to 4, characterized in that: The cross-sectional area of the first portion (21) gradually decreases from one end of the first portion (21) toward the second portion (22) to one end of the first portion (21) away from the second portion (22).

6. A battery cover, characterized in that: It comprises a top cover sheet (3) and the lower plastic according to any one of claims 1 to 5, wherein the top cover sheet (3) is provided with a connection groove (31) for accommodating the connection block (2) at a position corresponding to the connection block (2), and the connection block (2) is embedded in the connection groove (31) by ultrasonic welding.

7. The battery cover according to claim 6, characterized in that: The top cover plate (3) is further provided with a limiting groove (32), which is arranged at one end of the connecting groove (31) away from the plastic plate (1), and the limiting groove (32) is communicated with the connecting groove (31) and is used to limit the position of the connecting block (2) in the connecting groove (31) after melting.

8. The battery cover according to claim 7, characterized in that: The minimum cross-sectional area of the limiting groove (32) is not less than the minimum cross-sectional area of the connecting groove (31); and / or the maximum cross-sectional area of the limiting groove (32) is not greater than the maximum cross-sectional area of the connecting groove (31).

9. The battery cover according to claim 7, characterized in that: The minimum cross-sectional area of the connecting groove (31) and the minimum cross-sectional area of the limiting groove (32) are both greater than the maximum cross-sectional area of the connecting block (2).

10. A battery, characterized in that: It comprises a shell, a battery cell and a battery cover as described in any one of claims 6 to 9, wherein the battery cell is arranged inside the shell, and the battery cover is fixedly connected to the shell.

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