Cylindrical battery cell current collector and battery

Abstract

The utility model discloses a cylindrical electric core current collecting disc and battery, wherein the cylindrical electric core current collecting disc at least includes the round sheet shape current collecting disc that is adapted with electric core cylinder and the diameter is less than the electric core roll core diameter, the round sheet shape current collecting disc includes positive pole current collecting disc and negative pole current collecting disc, wherein the square tab is provided on the positive pole current collecting disc, the vertical distance of each side length of square tab is less than the positive pole current collecting disc circumferential edge any point to square tab, and only one side of square tab is connected with the positive pole current collecting disc, so that square tab is folded on the positive pole current collecting disc based on the connected side, thereby avoiding the positive pole current collecting disc in the cylindrical electric core current collecting disc and the inside contact of steel shell when preparing full tab cylindrical battery, improving the production efficiency and reducing the production cost.

Description

Technical Field

[0001] This utility model relates to the field of battery manufacturing, specifically to a cylindrical cell current collector and battery. Background Technology

[0002] In the fabrication of a cylindrical battery with multiple tabs, the pre-reserved foil at both ends of the cylindrical core needs to be welded to current collectors. These current collectors are divided into positive and negative current collectors. When welding the pre-reserved foil at both ends of the cylindrical core to the current collectors, one side of the negative current collector needs to be welded to the copper foil at the bottom of the cylindrical core, and the other side to the bottom of the cylindrical steel shell of the battery, so that the entire outer side of the cylindrical steel shell of the battery is negative. The positive current collector is welded to the aluminum foil at the top of the cylindrical core. Then, the positive current collector is welded to the aluminum metal part in the center of the cylindrical cell cap, so that the positive and negative electrodes of the battery are isolated by the insulating gasket of the cap. Sealing the cylindrical cell is achieved by grooving. Specifically, the cap with the welded positive current collector is placed into the groove, and then pressed using a sealing mold, pressing the edge of the steel shell and the insulating ring of the cap together into an inward-curving shape, thus achieving the purpose of sealing.

[0003] In a fully tabbed cylindrical battery, the entire circumferential edge of the positive and negative current collectors serves as a conductive channel, directly connecting to the cap of the cylindrical cell to form a multi-path current conduction. This allows the entire circumferential edge of the current collectors to function as tabs. However, to prevent the positive current collector tab from contacting the inner wall of the grooving during cell sealing, which could cause a short circuit and potentially lead to an explosion or fire, an adhesive application step can be added before sealing. This involves attaching insulating tape to the positive current collector tab. However, this operation increases the number of steps in the manufacturing process of the fully tabbed cylindrical battery, reducing manufacturing efficiency and increasing production costs.

[0004] Therefore, it is necessary to provide a type of cylindrical cell current collector to avoid contact between the positive current collector in the cylindrical cell current collector and the inside of the steel shell during the fabrication of all-tab cylindrical batteries, thereby improving manufacturing efficiency and reducing manufacturing costs. Utility Model Content

[0005] In view of this, the present invention provides a cylindrical cell current collector and battery, which avoids the positive current collector in the cylindrical cell current collector from contacting the inside of the steel shell when manufacturing a cylindrical battery with multiple tabs, thereby improving manufacturing efficiency and reducing manufacturing costs.

[0006] To achieve the above objectives, the present invention provides the following technical solutions.

[0007] In a first aspect, the present invention provides a cylindrical battery cell current collector, which includes at least a circular current collector adapted to the battery cell cylinder and having a diameter smaller than the diameter of the battery cell core. The circular current collector includes a positive current collector and a negative current collector.

[0008] The positive current collector is provided with a square tab, the length of each side of the square tab is less than the vertical distance from a point on the circumferential edge of the positive current collector to the square tab, and the square tab is connected to the positive current collector on only one side, so that the square tab is folded on the positive current collector based on the connected side.

[0009] Optionally, the square tab is specifically rectangular.

[0010] Optionally, the positive current collector is also provided with welding holes.

[0011] Optionally, the weld hole is a circular hole.

[0012] Optionally, the number of weld holes is 6.

[0013] Optionally, the square tab is provided with a tab fusion point; wherein, the tab fusion point is provided based on the center point of the square tab and along the two opposite edges of the square tab.

[0014] Optionally, the electrode tab melting point is arc-shaped, and the diameter of the electrode tab melting point is less than half the side length of the side of the square electrode tab without the electrode tab melting point.

[0015] Secondly, this utility model provides a battery, including the cylindrical cell current collector as described above.

[0016] This invention includes at least a cylindrical cell current collector with a disc-shaped current collector that is adapted to the cell cylinder and has a diameter smaller than the diameter of the cell core. The disc-shaped current collector includes a positive current collector and a negative current collector. A square tab is provided on the positive current collector, and the length of each side of the square tab is less than the vertical distance from a point on the circumferential edge of the positive current collector to the square tab. The square tab is connected to the positive current collector on only one side, so that the square tab can be folded on the positive current collector based on the connected side. Therefore, when manufacturing a full-tab cylindrical battery, there is no need to perform an adhesive bonding step on the square tab, which can ensure that the square tab does not come into contact with the inner wall of the steel shell. This provides a structural basis for avoiding contact between the positive current collector and the inside of the steel shell, thereby improving manufacturing efficiency and reducing manufacturing costs. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0018] Figure 1 This is a side view of the cylindrical battery cell current collector provided in an embodiment of the present invention.

[0019] Figure 2 This is a top view of the cylindrical battery cell current collector provided in an embodiment of this utility model.

[0020] Figure 3 This is a schematic diagram of the structure of the cylindrical battery cell current collector placed behind the battery cell according to an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the cylindrical cell current collector before encapsulation provided in this embodiment of the utility model.

[0022] Figure 5 This is a schematic diagram of the structure of the cylindrical battery cell current collector after encapsulation according to an embodiment of this utility model. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] As described in the background section, based on the current cylindrical cell current collector structure, an additional adhesive application step is added before sealing the cylindrical cell, where insulating tape is applied to the tab of the positive current collector. However, by adding this adhesive application step to prevent the positive current collector in the cylindrical cell current collector from contacting the inside of the steel shell, manufacturing efficiency is reduced and manufacturing costs are increased.

[0025] In view of this, the present invention provides an improved cylindrical cell current collector, which includes at least a circular current collector adapted to the cell cylinder and having a diameter smaller than the diameter of the cell core. The circular current collector includes a positive current collector and a negative current collector. A square tab is provided on the positive current collector, the length of each side of the square tab is less than the vertical distance from a point on the circumferential edge of the positive current collector to the square tab, and only one side of the square tab is connected to the positive current collector. This allows the square tab to be folded on the positive current collector based on the connected side. Therefore, when manufacturing a full-tab cylindrical battery, there is no need to perform an adhesive bonding step on the square tab, which ensures that the square tab does not contact the inner wall of the steel shell. This provides a structural basis for avoiding contact between the positive current collector and the inside of the steel shell, thereby improving manufacturing efficiency and reducing manufacturing costs.

[0026] in, Figure 1 An exemplary side view of the cylindrical cell current collector in an embodiment of this utility model is shown. Figure 1 As shown, the cylindrical cell current collector can include at least a disc-shaped current collector, wherein the disc-shaped current collector can include a positive current collector 1 and a negative current collector 1. Figure 1 Only the positive current collector 1 is shown in the image.

[0027] To accurately package the cylindrical battery cell, the circular current collector of this utility model embodiment can be adapted to the battery cell cylinder, and its diameter is smaller than the diameter of the battery cell core.

[0028] Reference Figure 1 As shown, a square tab 2 is provided on the positive current collector 1 of this embodiment of the present invention. As an optional implementation, the center point of the square tab may coincide with the center point of the positive current collector.

[0029] correspond Figure 1 , Figure 2 An exemplary top view of the cylindrical current collector of this utility model is shown. The lengths of each side of the square tab (shown as a, b, c, d in the figure) are all less than the vertical distance from any point M on the circumferential edge of the positive current collector to the square tab. For example, if the length of two sides of the square tab is R1, and the vertical distance from any point M on the circumferential edge of the positive current collector 1 to the square tab 2 is R2, then R1 is less than R2. Furthermore, see... Figure 2 As shown, the square tab 2 has only one side ( Figure 2 The side d shown by the dashed line is connected to the positive current collector 1, meaning that the connected side is integrated with the positive current collector 1, so that the square electrode tab 2 can be based on the connected side (i.e. Figure 2 As shown, side d is folded in the positive current collector 1, so that the other three sides of the square electrode tab 2 (excluding the connected sides) are folded together. Figure 2 As shown, sides a, b, and c can move away from the positive current collector 1. In other words, in this embodiment of the invention, only one side of the square tab is connected to the positive current collector, allowing the square tab to fold based on this connected side. Taking the direction towards the cylindrical cell during packaging as positive and the direction away from the cylindrical cell as negative, to ensure that the square tab does not contact the inner wall of the steel casing, the square tab of this invention can fold away from the cylindrical cell.

[0030] It should be noted that the cylindrical current collector of this utility model embodiment can be obtained, for example, by using a stamping machine to stamp a square tab in the center of a circular conductive material (e.g., a circular aluminum sheet) that meets the conditions.

[0031] Understandably, since the square tabs on the positive current collector are connected to the positive current collector on only one side, the square tabs can be folded on the positive current collector based on this connected side. Furthermore, when the length of each side of the square tab is less than the vertical distance from any point on the circumferential edge of the positive current collector to the square tab, the square tabs avoid touching the edge of the positive current collector when folded on it, ensuring that the square tabs do not contact the inner wall of the steel shell. Therefore, when manufacturing a full-tab cylindrical battery, there is no need to perform an adhesive application step on the square tabs, providing a structural basis for avoiding contact between the positive current collector and the inside of the steel shell, improving manufacturing efficiency, and reducing manufacturing costs.

[0032] As can be seen, this utility model includes at least a cylindrical cell current collector with a circular current collector that is adapted to the cell cylinder and has a diameter smaller than the diameter of the cell core. The circular current collector includes a positive current collector and a negative current collector. A square tab is provided on the positive current collector. The length of each side of the square tab is less than the vertical distance from any point on the circumferential edge of the positive current collector to the square tab. Only one side of the square tab is connected to the positive current collector, so that the square tab can be folded on the positive current collector based on the connected side. Therefore, when manufacturing a full-tab cylindrical battery, there is no need to perform an adhesive application step on the square tab, which can ensure that the square tab does not come into contact with the inner wall of the steel shell. This provides a structural basis for avoiding contact between the positive current collector and the inside of the steel shell, thereby improving manufacturing efficiency and reducing manufacturing costs.

[0033] See also Figure 2 As shown, in some embodiments, to better reflect the performance of the cylindrical cell current collector, the square tab 2 of this utility model embodiment can be specifically rectangular.

[0034] In some embodiments, to enhance the soldering design of the prepared cylindrical battery with full tabs and the welding quality of the welding with the core aluminum foil, and to reduce the internal resistance of the cell, the positive current collector 1 of the cylindrical cell current collector in this embodiment of the present invention is also provided with a welding hole 3.

[0035] In a specific example, the weld hole 3 can be designed as a circular hole. It should be noted that, since the positive electrode current collector has a circular hole, the wettability of the electrolyte can be effectively enhanced when performing the electrolyte injection operation during the fabrication of the all-tab cylindrical battery.

[0036] In an optional implementation, to effectively reflect the role of weld holes in the design of the weld pattern, the welding quality of the weld to the aluminum foil core, and the enhancement of electrolyte wetting, the number of weld holes provided on the positive current collector in this embodiment of the present invention can be 6.

[0037] In some embodiments, the square tab 2 of the positive current collector 1 in the cylindrical current collector of this utility model embodiment may also be provided with tab melting points 4. The tab melting points 4 may be located on the two relatively movable edges of the square tab 2 based on the center point of the square tab 2.

[0038] In one optional example, the electrode fuse point 4 can be arc-shaped, and the diameter of the electrode fuse point 4 is less than half the side length of the side of the square electrode 2 where the electrode fuse point 4 is not located. For example: Figure 2 If the side length of the square tab 1 without the tab melting point 4 is X, then the diameter of the tab melting point 4 is less than (X / 2).

[0039] It is understandable that because the square tab 2 is provided with an arc-shaped tab fuse point 4, the width of the square tab 2 at the tab fuse point 4 is reduced and the cross-sectional area is reduced. When the cell is short-circuited externally, the high resistance at this point will generate a large amount of heat, thereby causing the tab to melt and achieve the purpose of physically isolating the external short circuit, thus enhancing the safety of the cell.

[0040] To clearly understand the cylindrical cell current collector design of this utility model embodiment, Figure 3 An exemplary schematic diagram of a cylindrical battery cell current collector placed behind the battery cell is shown in an embodiment of this utility model. Figure 3 The structure shown is... Figure 4 and Figure 5 The diagrams show the structural schematics of the cylindrical battery cell current collector before and after packaging according to embodiments of this utility model.

[0041] As can be seen, this utility model includes at least a cylindrical battery cell current collector with a disc-shaped current collector that is adapted to the battery cell cylinder and has a diameter smaller than that of the battery cell core 6. The disc-shaped current collector includes a positive current collector 1 and a negative current collector 2. Figure 4 and Figure 5 (Not shown) A square tab 2 is provided on the positive current collector 1. The length of each side of the square tab 2 is less than the vertical distance from a point on the circumferential edge of the positive current collector 1 to the square tab 2. The square tab 2 is connected to the positive current collector 1 on only one side, so that the square tab 2 can be folded on the positive current collector 1 based on the connected side. Therefore, when manufacturing a full-tab cylindrical battery, there is no need to perform an adhesive application step on the square tab 2, which can ensure that the square tab 2 does not come into contact with the inner wall of the steel shell 5. This provides a structural basis for avoiding contact between the positive current collector 1 and the inside of the steel shell 5, thereby improving manufacturing efficiency and reducing manufacturing costs.

[0042] This utility model embodiment also provides a battery, including the above-described cylindrical cell current collector.

[0043] The foregoing describes multiple embodiments of the present invention. The optional methods described in each embodiment can be combined and cross-referenced without conflict, thereby extending to a variety of possible embodiments. These can all be considered as embodiments disclosed or made public by the present invention.

[0044] While the embodiments of this utility model have been disclosed above, this utility model is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of this utility model; therefore, the scope of protection of this utility model should be determined by the scope defined in the claims.

Claims

1. A cylindrical battery cell current collector, characterized in that, It includes at least a circular current collector that is adapted to the battery cell cylinder and has a diameter smaller than that of the battery cell core, wherein the circular current collector includes a positive current collector and a negative current collector; The positive current collector is provided with a square tab, the length of each side of the square tab is less than the vertical distance from any point on the circumferential edge of the positive current collector to the square tab, and only one side of the square tab is connected to the positive current collector, so that the square tab is folded on the positive current collector based on the connected side.

2. The cylindrical cell current collector according to claim 1, characterized in that, The square tab is specifically rectangular.

3. The cylindrical cell current collector according to claim 1, characterized in that, The positive current collector is also provided with welding holes.

4. The cylindrical cell current collector according to claim 3, characterized in that, The weld hole is a circular hole.

5. The cylindrical cell current collector according to claim 3, characterized in that, The number of weld holes is 6.

6. The cylindrical cell current collector according to claim 1, characterized in that, The square electrode tab is also provided with an electrode tab melting point; wherein, the electrode tab melting point is based on the center point of the square electrode tab and is located on the two relatively movable edges of the square electrode tab.

7. The cylindrical cell current collector according to claim 6, characterized in that, The electrode tab melting point is arc-shaped, and the diameter of the electrode tab melting point is less than half the side length of the side of the square electrode tab that does not have an electrode tab melting point.

8. A battery, characterized in that, Includes the cylindrical cell current collector as described in any one of claims 1 to 7.

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