Battery cell cover plate assembly and battery cell assembly

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cell cover plate assembly, a battery cell assembly and a first cover plate. A second cover plate; the connecting piece assembly comprises a first connecting piece and a second connecting piece, and the first connecting piece comprises a pole connecting part and a tab connecting part which are connected in sequence; the pole component comprises a first pole and a second pole; and the plug comprises a sealing plate and an insulating plate which are sequentially arranged from top to bottom, and the sealing plate and the insulating plate are in fusion connection through the connecting column and the connecting groove. According to the utility model, the top surface of the first cover plate is provided with the welding holes, the tabs and the connecting pieces can be directly welded through the welding holes when the battery cell assembly is assembled, and the component assembly sequence of the battery cell assembly is changed through a simple structure, so that the first cover plate, the first connecting pieces and the first pole columns can be pre-assembled in advance; the sealing plate and the insulating plate are in fusion connection through the groove and the column, the production process is simple and efficient, and meanwhile the connection reliability of the sealing plate and the insulating plate can be improved.

Description

Technical Field

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

[0002] With the rapid development of new energy technologies, power batteries have been increasingly widely used in various electric tools and new energy vehicles due to their excellent characteristics. One of the important indicators that cannot be ignored during the use of power batteries is safety. Power batteries not only need to have a high capacity but also should have good reliability in use. As an important part of power batteries, the cover plate assembly plays a role in guiding current and sealing the power batteries.

[0003] Currently, the electrode tabs of the battery cells of existing power batteries are mainly connected to the corresponding electrode posts through connecting pieces. The corresponding positions of the electrode tabs and the connecting pieces are connected by welding to ensure their current-carrying capacity. When manufacturing power batteries, it is necessary to send independent battery cells, connecting pieces, electrode posts, cover plates and other components to the assembly workshop before the components can be assembled in sequence. The entire assembly process has many steps and takes a long time, which is time-consuming and laborious, and there is a problem of low production efficiency. Summary of the Utility Model

[0004] In view of this, the utility model provides a battery cell cover plate assembly and a battery cell assembly to solve the problem of low assembly production efficiency of existing power batteries.

[0005] In a first aspect, the utility model provides a battery cell cover plate assembly, including: a first cover plate, on the top surface of which there are a first connection hole and a welding hole; a second cover plate, on the bottom surface of which there is a second connection hole; a connecting piece assembly, including a first connecting piece and a second connecting piece, the first connecting piece includes a pole connection part and an electrode tab connection part connected in sequence, the pole connection part is correspondingly arranged with the first connection hole, the electrode tab connection part is correspondingly arranged with the welding hole, and the electrode tab connection part is used for connecting with the electrode tab on one side of the battery cell; a pole assembly, including a first pole and a second pole, the first pole is connected to the pole connection part of the first connecting piece through the first connection hole, and the second pole is connected to the second connecting piece through the second connection hole; a plugging member, which is matched with the shape of the welding hole and is used for plugging the welding hole, the plugging member includes a sealing plate and an insulating plate arranged in sequence from top to bottom, the sealing plate is connected to the first cover plate, one of the sealing plate and the insulating plate is provided with a connecting post and the other is provided with a connecting groove, and the sealing plate and the insulating plate are melt-connected through the connecting post and the connecting groove.

[0006] Beneficial effects: Welding holes are provided on the top surface of the first cover plate. When assembling the battery cell assembly, the tab and the connecting piece can be directly welded through the welding holes. By simply changing the structure, the assembly sequence of the components of the battery cell assembly is changed, avoiding the situation where the connecting piece needs to be welded to the tab alone before the remaining components can be assembled. This enables the pre-assembly of the first cover plate, the first connecting piece, and the first pole column, greatly reducing the assembly steps during the assembly of the battery cell assembly. In addition, the sealing plate and the insulating plate are melt-connected in the form of a groove and a column, which not only simplifies the production process and improves efficiency but also enhances the connection reliability between the sealing plate and the insulating plate, effectively solving the problem of low assembly production efficiency of existing power batteries.

[0007] In an alternative embodiment, a connecting groove with a downward opening is provided on the bottom surface of the sealing plate, and a connecting column extending upward is provided on the top surface of the insulating plate. The cross-sectional area of the connecting groove gradually decreases from top to bottom.

[0008] Beneficial effects: After melting, the connecting column can form a connecting body that matches the groove body of the connecting groove, not only increasing the contact area of the melt connection but also effectively preventing the connecting column from detaching from the connecting groove, further enhancing the connection strength between the sealing plate and the insulating plate.

[0009] In an alternative embodiment, the cross-sections of both the connecting groove and the connecting column are circular. The diameter range of the opening of the connecting groove is 0.5 mm to 0.6 mm, and / or the diameter of the cross-section at the opening of the connecting groove is at least 0.3 mm smaller than the diameter of the cross-section at the top surface of the connecting groove.

[0010] Beneficial effects: This form of connecting groove and connecting column is convenient for manufacturing and can also ensure the fixing effect after melt connection.

[0011] In an alternative embodiment, the thickness range from the top surface of the connecting groove to the top surface of the sealing plate is 0.2 mm to 1.5 mm.

[0012] Beneficial effects: Ensure that the strength of the sealing plate meets the usage requirements.

[0013] In an alternative embodiment, the height of the connecting column before assembly is at least 0.25 mm greater than the depth of the connecting groove, which can effectively ensure the strength of the melt connection.

[0014] In an alternative embodiment, the ratio of the opening area of the welding hole to the area of the first cover plate ranges from 0.2 to 0.6, and / or a liquid injection hole and an explosion-proof valve are also provided on the second cover plate.

[0015] Beneficial effects: While meeting the overcurrent requirement of the first connecting piece, ensure that the first cover plate has sufficient structural strength. The liquid injection hole and the explosion-proof valve located on the second cover plate can avoid occupying the space of the first cover plate, making the selection of the opening position and the cross-sectional size of the welding hole more flexible.

[0016] In an optional embodiment, the top surface of the pole tab connecting portion forms a connection surface for connecting with the pole tab.

[0017] Beneficial effect: Since the connection surface connected to the pole ear is located at the top of the pole ear connection part, after the pole ears are connected to the pole ear connection parts, not only is the structure more compact and occupies less space, but when the pole ear connection part is pulled down by the pole ear, one side of the pole connection part will tend to curl up, so that the poles and pole connections can fit more closely and reduce the risk of separation.

[0018] In an optional embodiment, the welding hole includes a first hole segment and a second hole segment from top to bottom, the cross-sectional area of the second hole segment is smaller than the cross-sectional area of the first hole segment, the connecting surface of the first hole segment and the second hole segment forms a step surface, and the sealing plate cooperates with the step surface.

[0019] Beneficial effect: The step surface can quickly and effectively locate the sealing plate in the vertical direction, thereby improving the assembly accuracy and speed of the sealing piece.

[0020] In an optional embodiment, the blocking member is provided with a plurality of connection grooves and connection columns in pairs and at intervals along its length direction.

[0021] Beneficial effects: The connection groove and the connection column are melt-connected at multiple positions along the length direction, ensuring that the two components can fit tightly, meeting the insulation performance between the pole ear and the sealing plate, and improving the reliability of the battery.

[0022] In the second aspect, the utility model also provides a battery cell assembly, which includes: the above-mentioned battery cell cover assembly; a battery cell, wherein pole ears are respectively arranged on the top and the bottom, the pole ear located on the top includes a connecting section and a bending section, the connecting section is located on one side of the pole ear connecting part of the battery cell cover assembly, the bending section is connected to the top of the connecting section and extends along the top surface of the pole ear connecting part, and the pole ear located on the top is welded to the pole ear connecting part. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A three-dimensional schematic diagram of a battery cell cover assembly from a first perspective according to an embodiment of the utility model;

[0025] Figure 2 for Figure 13D schematic diagram of the second perspective of the cell cover plate assembly shown;

[0026] Figure 3 is Figure 1 Cross-sectional view of the cell cover plate assembly shown;

[0027] Figure 4 is Figure 3 Partial enlarged schematic diagram of the first cover plate shown;

[0028] Figure 5 is Figure 1 Exploded schematic diagram of the plugging member of the cell cover plate assembly shown;

[0029] Figure 6 3D schematic diagram of a cell assembly according to an embodiment of the present invention;

[0030] Figure 7 is Figure 6 3D schematic diagram of the cell assembly shown after being flipped;

[0031] Figure 8 is Figure 6 Cross-sectional view of the cell assembly shown;

[0032] Figure 9 is Figure 6 3D schematic diagram of the cell assembly shown without the plugging member being shown;

[0033] Figure 10 is Figure 9 3D schematic diagram of the cell assembly shown when the tabs are not bent and not welded.

[0034] Explanation of reference numerals:

[0035] 1. First cover plate; 101. First connection hole; 102. Welding hole; 1021. First hole section; 1022. Second hole section; 1023. Step surface;

[0036] 2. Second cover plate; 201. Second connection hole; 202. Explosion-proof valve; 203. Liquid injection hole;

[0037] 3. First connection piece; 301. Pole connection part; 302. Tab connection part; 3021. Connection surface;

[0038] 4. Second connection piece;

[0039] 5. First pole; 501. First riveting block;

[0040] 6. Second pole; 601. Second riveting block;

[0041] 7. Plugging member; 701 Sealing plate; 7011 Connecting groove; 702 Insulating plate; 7021 Connecting post;

[0042] 8. Battery cell; 801 Tab;

[0043] 9. Housing. Detailed implementation manner

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0045] The following combines Figures 1 to 10 , to describe the embodiments of the present utility model.

[0046] According to an embodiment of the present utility model, on the one hand, a battery cell cover assembly is provided, including: a first cover plate 1, a second cover plate 2, a connecting piece assembly, a terminal post assembly, and a plugging member 7. A first connecting hole 101 and a welding hole 102 are provided on the top surface of the first cover plate 1, and a second connecting hole 201 is provided on the bottom surface of the second cover plate 2. The connecting piece assembly includes a first connecting piece 3 and a second connecting piece 4. The first connecting piece 3 includes a terminal post connecting portion 301 and a tab connecting portion 302 connected in sequence. The terminal post connecting portion 301 is correspondingly arranged with the first connecting hole 101, and the tab connecting portion 302 is correspondingly arranged with the welding hole 102. The tab connecting portion 302 is used to connect with the tab 801 on one side of the battery cell 8. The terminal post assembly includes a first terminal post 5 and a second terminal post 6. The first terminal post 5 is connected to the terminal post connecting portion 301 of the first connecting piece 3 through the first connecting hole 101, and the second terminal post 6 is connected to the second connecting piece 4 through the second connecting hole 201. The plugging member 7 matches the shape of the welding hole 102 and is used to plug the welding hole 102. The plugging member 7 includes a sealing plate 701 and an insulating plate 702 arranged in sequence from top to bottom. The sealing plate 701 is connected to the first cover plate 1. One of the sealing plate 701 and the insulating plate 702 is provided with a connecting post 7021 and the other is provided with a connecting groove 7011. The sealing plate 701 and the insulating plate 702 are melt-connected through the connecting post 7021 and the connecting groove 7011.

[0047] When applying the cell cover plate assembly of this embodiment, a welding hole 102 is opened on the top surface of the first cover plate 1. During the assembly of the cell assembly, the tab 801 and the first connecting piece 3 can be directly welded through the welding hole 102. By simply changing the structure, the component assembly sequence of the cell assembly is changed, avoiding the situation where the first connecting piece 3 needs to be welded to the tab 801 separately before the remaining components can be assembled. This enables the pre-assembly of the first cover plate 1, the first connecting piece 3, and the first pole 5 in advance, greatly reducing the assembly steps during the assembly of the cell assembly. In addition, the sealing plate 701 and the insulating plate 702 are melt-connected in the form of a groove and a column, which not only simplifies the production process and improves efficiency but also enhances the connection reliability between the sealing plate 701 and the insulating plate 702, effectively solving the problem of low assembly production efficiency of existing power batteries.

[0048] Here, it should be noted that the top refers to Figure 3 the side in the "up" direction indicated by the arrow in Figure 3 and the bottom refers to

[0049] Specifically, the connection method between the plugging member 7 and the first cover plate 1 is not limited and can be welding, bonding, or connection through fastening components, etc., which can be flexibly selected according to requirements.

[0050] Furthermore, compared with the connection of the sealing plate 701 and the insulating plate 702 through independent connecting components, the melt-connection of the sealing plate 701 and the insulating plate 702 in the form of a groove and a column has high strength and low cost, and can be mass-produced in a single process. After this form of connection, the overall appearance of the sealing plate 701 and the insulating plate 702 is more beautiful, the integrity of the outer wall is better, and problems such as liquid leakage are not likely to occur.

[0051] In a possible implementation manner, a downward-opening connection groove 7011 is provided on the bottom surface of the sealing plate 701, and an upward-extending connection post 7021 is provided on the top surface of the insulating plate 702. The cross-sectional area of the connection groove 7011 gradually decreases from top to bottom. After the connection post 7021 is melted, it can form a connection body that matches the groove body of the connection groove 7011, which not only increases the contact area of the melt-connection but also effectively prevents the connection post 7021 from detaching from the connection groove 7011, further enhancing the connection strength between the sealing plate 701 and the insulating plate 702.

[0052] It can be understood that as an alternative implementation manner, the cross-sectional area of the connection groove 7011 can also increase first and then decrease multiple times from top to bottom.

[0053] Here, it should be noted that the cross-section and the cross-sectional area refer to the section of the plane perpendicular to Figure 3 the "up and down" direction indicated by the arrow in Figure 5As shown, in order for the connecting post 7021 to be inserted into the connecting groove 7011, when the connecting post 7021 is not assembled, the maximum cross-sectional area of the connecting post 7021 is less than or equal to the maximum cross-sectional area of the connecting groove 7011. The melting connection step is carried out only after the connecting post 7021 is inserted into the connecting groove 7011.

[0054] Specifically, the specific shapes of the connecting post 7021 and the connecting groove 7011 are not limited. The cross-sections of the connecting post 7021 and the connecting groove 7011 can be rectangular, triangular, circular, etc., as long as they are convenient for processing, and can be flexibly selected according to requirements.

[0055] In a possible implementation manner, the cross-sections of both the connecting groove 7011 and the connecting post 7021 are circular. The diameter range of the opening of the connecting groove 7011 is 0.5 mm to 0.6 mm. The diameter of the cross-section at the opening of the connecting groove 7011 is at least 0.3 mm smaller than the diameter of the cross-section at the top surface of the connecting groove 7011. For the connecting groove 7011 and the connecting post 7021 in this form, it is convenient for manufacturing and can also ensure the fixing effect after melting connection.

[0056] In a possible implementation manner, the thickness range from the top surface of the connecting groove 7011 to the top surface of the sealing plate 701 is 0.2 mm to 1.5 mm, ensuring that the strength of the sealing plate 701 meets the usage requirements.

[0057] In a possible implementation manner, the height of the connecting post 7021 when not assembled is at least 0.25 mm greater than the depth of the connecting groove 7011, which can effectively ensure the strength of the melting connection.

[0058] In a possible implementation manner, the ratio range of the opening area of the welding hole 102 to the area of the first cover plate 1 is 0.2 to 0.6. The second cover plate 2 is also provided with a liquid injection hole 203 and an explosion-proof valve 202, which can meet the overcurrent requirement of the first connecting piece 3 while ensuring that the first cover plate 1 has sufficient structural strength. The liquid injection hole 203 and the explosion-proof valve 202 are located on the second cover plate 2, which can avoid occupying the space of the first cover plate 1 and make the selection of the opening position and the cross-sectional size of the welding hole 102 more flexible.

[0059] In a possible implementation manner, a connecting surface 3021 for connecting with the ear 801 is formed on the top surface of the ear connecting portion 302. Since the connecting surface 3021 connecting with the ear 801 is located at the top of the ear connecting portion 302, after the ear 801 is connected to the ear connecting portion 302, not only the structure is more compact and occupies less space, but when the ear 801 pulls down the ear connecting portion 302, one side of the pole column connecting portion 301 will have a tendency to tilt upward, making the first pole column 5 and the pole column connecting portion 301 fit more tightly and reducing the risk of separation.

[0060] In the related art, the first connecting piece 3 and the tab 801 of the battery cell 8 are usually arranged vertically. The bottom surface of the first connecting piece 3 is connected to the tab 801. In order to improve the connection reliability between the two, the tab 801 usually needs to be bent and welded and fixed to the bottom surface of the first connecting piece 3 through its outer wall. In this connection method, the tab 801 needs to occupy a large space, resulting in a cavity at the top of the battery cell assembly. In addition, the tab 801 will push up the first connecting piece 3, causing the pole connection part 301 of the first connecting piece 3 to tend to move downward under the action of the lever principle. Furthermore, the pole connection part 301 of the first connecting piece 3 is likely to be separated from the first pole 5, making the structural stability of the top of the battery cell assembly poor. However, the battery cell 8 cover plate assembly in this embodiment can reliably solve the defects existing in the above structural form.

[0061] In a possible implementation manner, the top surface of the sealing plate 701 is flush with the top surface of the first cover plate 1. After assembly, the sealing plate 701 is not likely to interfere with other components, occupies less space and is lighter in weight, and is also not likely to be separated from the first cover plate 1. At the same time, the sealing plate 701 in this form is also more aesthetically pleasing after assembly.

[0062] In a possible implementation manner, the welding hole 102 sequentially includes a first hole section 1021 and a second hole section 1022 from top to bottom. The cross-sectional area of the second hole section 1022 is smaller than that of the first hole section 1021. The connection surface 3021 between the first hole section 1021 and the second hole section 1022 forms a step surface 1023. The sealing plate 701 cooperates with the step surface 1023. The step surface 1023 can quickly and effectively position the vertical position of the sealing plate 701, thereby improving the assembly accuracy and assembly speed of the plugging member 7.

[0063] Specifically, as Figure 4 shown, the area of the insulating plate 702 is smaller than that of the sealing plate 701. Therefore, it can avoid the problem that when the sealing plate 701 cooperates with the step surface 1023, interference occurs between the step surface 1023 and the insulating plate 702, resulting in inability to install.

[0064] It can be understood that as an alternative implementation manner, the welding hole 102 can also be a through hole with a consistent diameter or a hole with an inclined inner wall.

[0065] In a possible implementation manner, a plurality of connecting grooves 7011 and connecting posts 7021 are arranged in pairs and at intervals along the length direction of the plugging member 7. The connecting grooves 7011 and the connecting posts 7021 are melt-connected at multiple positions along the length direction, ensuring that the two components can be closely attached, meeting the insulation performance between the tab 801 and the sealing plate 701, and improving the reliability of the battery.

[0066] Among them, the specific number of the connecting grooves 7011 and the connecting posts 7021 is not limited, and they can be arranged in a single row or in an array, and can be flexibly selected according to requirements.

[0067] In a possible implementation manner, a first riveting block 501 is arranged at the first connection hole 101, and the upper part of the first pole 5 passes through the first riveting block 501 and is in riveting cooperation with the first riveting block 501; a second riveting block 601 is arranged at the second connection hole 201, and the lower part of the second pole 6 passes through the second riveting block 601 and is in riveting cooperation with the second riveting block 601.

[0068] Furthermore, as Figure 3 shown, the pole connection part 301 of the first connection piece 3 and the first pole 5 are of an integral structure, which not only has higher structural strength but also can omit the intermediate connection steps.

[0069] It can be understood that as an alternative implementation manner, the pole connection part 301 and the first pole 5 can also be a split independent structure, and the pole connection part 301 and the first pole 5 are connected by welding.

[0070] According to an embodiment of the present invention, on the other hand, a battery cell assembly is provided, which includes: the above-mentioned battery cell cover assembly and the battery cell 8. The top and bottom of the battery cell 8 are respectively provided with electrode tabs 801. The electrode tab 801 located at the top includes a connection section and a bending section. The connection section is located on one side of the electrode tab connection part 302 of the battery cell cover assembly. The bending section is connected to the top of the connection section and extends along the top surface of the electrode tab connection part 302. The electrode tab 801 located at the top is welded to the electrode tab connection part 302.

[0071] Specifically, the battery cell assembly further includes a housing 9. The inside of the housing 9 has an accommodation space and openings are provided on both the upper and lower sides. The battery cell 8 is arranged in the accommodation space. The first cover 1 of the battery cell cover assembly is located at the top opening of the housing 9, and the second cover 2 of the battery cell cover assembly is located at the bottom opening of the housing 9.

[0072] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cell cover plate assembly, characterized in that, Comprising: A first cover plate, on the top surface of which there are a first connection hole and a welding hole; A second cover plate, on the bottom surface of which there is a second connection hole; A connecting piece assembly, including a first connecting piece and a second connecting piece, the first connecting piece includes a pole column connecting part and an ear connecting part connected in sequence, the pole column connecting part is correspondingly arranged with the first connection hole, the ear connecting part is correspondingly arranged with the welding hole, and the ear connecting part is used for connecting with the ear on one side of the battery cell; A pole column assembly, including a first pole column and a second pole column, the first pole column is connected to the pole column connecting part of the first connecting piece through the first connection hole, and the second pole column is connected to the second connecting piece through the second connection hole; A plugging piece, which is matched with the shape of the welding hole and is used for plugging the welding hole, the plugging piece includes a sealing plate and an insulating plate arranged in sequence from top to bottom, the sealing plate is connected to the first cover plate, one of the sealing plate and the insulating plate is provided with a connecting column and the other is provided with a connecting groove, and the sealing plate and the insulating plate are melt-connected through the connecting column and the connecting groove; On the bottom surface of the sealing plate, there is the connecting groove with a downward opening, on the top surface of the insulating plate, there is the connecting column extending upward, and the cross-sectional area of the connecting groove gradually decreases from top to bottom; The thickness range from the top surface of the connecting groove to the top surface of the sealing plate is 0.2 mm to 1.5 mm; The height of the connecting column when not assembled is at least 0.25 mm larger than the depth of the connecting groove.

2. The cell cover plate assembly according to claim 1, wherein The cross-sections of the connecting groove and the connecting column are both circular, the diameter range of the opening of the connecting groove is 0.5 mm to 0.6 mm, and / or, the diameter of the cross-section of the opening of the connecting groove is at least 0.3 mm smaller than the diameter of the cross-section of the connecting groove at the top surface; 3. The cell cover plate assembly according to claim 1 or 2, characterized in that, The ratio range of the opening area of the welding hole to the area of the first cover plate is 0.2 to 0.6, and / or, a liquid injection hole and an explosion-proof valve are further arranged on the second cover plate.

4. The cell cover plate assembly according to claim 1 or 2, characterized in that, On the top surface of the ear connecting part, a connecting surface for connecting with the ear is formed.

5. The cell cover plate assembly according to claim 1 or 2, characterized in that, The welding hole sequentially includes a first hole section and a second hole section from top to bottom, the cross-sectional area of the second hole section is smaller than that of the first hole section, and the connecting surface of the first hole section and the second hole section forms a stepped surface, and the sealing plate is matched with the stepped surface.

6. The cell cover plate assembly according to claim 1 or 2, characterized in that, Along the length direction of the plugging piece, a plurality of the connecting grooves and the connecting columns are arranged in pairs and at intervals.

7. A battery cell assembly, characterized in that, Comprising: The battery cell cover plate assembly according to any one of claims 1 to 6; A battery cell, with ears respectively arranged at the top and the bottom, the ear at the top includes a connecting section and a bent section, the connecting section is located on one side of the ear connecting part of the battery cell cover plate assembly, the bent section is connected to the top of the connecting section and extends along the top surface of the ear connecting part, and the ear at the top is welded to the ear connecting part.

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