Cell tab tension measuring device and cell tab tension measuring method

Abstract

As one embodiment, the present invention provides a cell tab tension measuring device for a cell including a tab and a lead connected to the tab, the cell tab tension measuring device including a pair of jigs for fixing the tab, a pair of bending dies for bending the lead, and a tension measuring device connected to the cell for measuring the tension applied to the tab when the lead is bent.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0000163 dated January 3, 2022, and all contents disclosed in the documents of the Korean patent application are incorporated herein by reference.

[0002] The present disclosure relates to a cell tab tension measuring device and a cell tab tension measuring method. [Background technology]

[0003] As technology development and demand for mobile devices increases, rechargeable secondary batteries are widely used as energy sources for various mobile devices. Secondary batteries are also attracting attention as energy sources for electric vehicles and hybrid vehicles, which have been presented as a solution to solve air pollution caused by existing gasoline and diesel vehicles.

[0004] Secondary batteries are classified into coin type batteries, cylindrical batteries, prismatic batteries, and pouch type batteries depending on the shape of the battery case. Among these, in the case of pouch type batteries, the cell leads may be bent in order to arrange multiple cells on a bus bar, etc. In this case, during the process of bending the leads, tension may be applied to the tabs connected to the leads, causing the tabs to break. However, currently there is no device that can check for the possibility of tab breakage. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Republic of Korea Publication Patent No. 10-2021-0021871 (March 2, 2021) Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a cell tab tension measuring device and a cell tab tension measuring method that can measure the tension applied to a tab and thereby prevent breakage of the tab. [Means for solving the problem]

[0007] As one embodiment, the present invention provides a cell tab tension measuring device for a cell including a tab and a lead connected to the tab, the cell tab tension measuring device including a pair of jigs for fixing the tab, a pair of bending dies for bending the lead, and a tension measuring device connected to the cell for measuring the tension applied to the tab when the lead is bent.

[0008] In another embodiment, the present invention provides a cell tab tension measuring method for a cell including a tab and a lead connected to the tab, the method including the steps of fixing the tab, bending the lead, and measuring the tension applied to the tab when the lead is bent. Effect of the Invention

[0009] The present invention can provide a cell tab tension measuring device and a cell tab tension measuring method that can measure the tension applied to a tab and thereby prevent breakage of the tab. [Brief description of the drawings]

[0010] [Figure 1] FIG. 13 shows the tabs of the cell being fixed in a jig and the leads being bent with a bending die. [Diagram 2] FIG. 2 illustrates a cell tab tension measuring device according to one embodiment of the present invention. [Diagram 3] 1 is a diagram showing a state in which a tension measuring device according to an embodiment of the present invention is connected to a cell; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, some or all of the components may be exaggerated for ease of explanation.

[0012] Furthermore, it will be apparent to those skilled in the art that the present invention is not limited to the attached drawings or the contents described in this specification, and that the present invention can be embodied in various forms without departing from the technical spirit of the present invention.

[0013] FIG. 1 shows the tabs of a cell being fixed in a jig and the leads being bent with a bending die.

[0014] Referring to the drawing, the cell 10 includes a tab 10T and a lead 10L connected to the tab. Although not specifically shown, the body 10B of the cell 10 may have a structure in which an electrode assembly including a positive electrode and a negative electrode is sealed in a pouch together with an electrolyte, and the cell 10 may be a pouch-type cell. The configuration, structure, shape, etc. of the cell 10 including the tab 10T and the lead 10L are not particularly limited, and various types of cells used in the art may be used to implement the present invention.

[0015] 1(a), first, the tab 10T of the cell 10 is fixed by a pair of jigs 110. The pair of jigs 110 includes an upper jig 111 and a lower jig 112. At this time, the pair of jigs 110 may pressurize the tab 10T from both sides of the tab 10T to fix it. Specifically, the upper jig 111 may be lowered and the lower jig 112 may be raised, and these jigs may come into contact with both sides of the tab 10T, and the tab 10T may be pressed from both sides of the tab 10T to fix it.

[0016] 1(b), the lead 10L of the cell 10 is then bent by a pair of bending dies 120. The pair of bending dies 120 includes an upper bending die 121 and a lower bending die 122. At this time, the pair of bending dies 120 may bend the lead 10L by applying pressure to both sides of the lead 10L. Specifically, the upper bending die 121 may be lowered and the lower bending die 122 may be raised, so that these bending dies come into contact with both sides of the lead 10L and bend the lead 10L by applying pressure to both sides of the lead 10L.

[0017] The pair of bending dies 120 may have shapes that interdigitate with each other. In other words, the upper bending die 121 and the lower bending die 122 may have shapes that correspond to each other, for example, in a region where the upper bending die 121 has a concave portion, the lower bending die 122 may have a convex portion having a shape corresponding to the concave portion of the upper bending die 121, and in a region where the upper bending die 121 has a convex portion, the lower bending die 122 may have a concave portion having a shape corresponding to the convex portion of the upper bending die 121. Therefore, the pair of bending dies 120 interdigitate with each other by the upper bending die 121 descending and the lower bending die 122 ascending, and the lead 10L disposed between them can be bent by applying pressure from both sides of the lead 10L.

[0018] The cell 10 may be transported by the transport unit 140. The cell 10 being transported by the transport unit 140 may stop for a certain period of time in an area where the lead 10L is to be bent, the tab 10T may be fixed by the jig 110, and the lead 10L may be bent by the bending die 120. The transport unit 140 may be, but is not limited to, a conveyor belt. The transport unit 140 may transport the cell 10 in a direction to protrude from and / or enter into the drawing.

[0019] On the other hand, in order to arrange a plurality of cells on a bus bar or the like, the lead 10L of the cell 10 may be bent. In this case, when the tab 10T is fixed by the jig 110 and the lead 10L is bent by the bending die 120 as described above, tension is applied to the cell 10, particularly the tab 10T connected to the lead 10L, which may cause breakage of the tab 10T. Therefore, a device capable of checking the possibility of breakage of the tab 10T is required.

[0020] FIG. 2 is a diagram showing a cell tab tension measuring device according to one embodiment of the present invention.

[0021] The cell tab tension measuring device 100 according to an embodiment of the present invention includes a pair of jigs 110 for fixing the tab 10T shown in Fig. 1, and a pair of bending dies 120 for bending the lead 10L, and further includes a tension measuring device 130 for measuring the tension applied to the tab 10T when the lead 10L is bent. In addition, the cell tab tension measuring device 100 according to an embodiment of the present invention may further include a transport unit 140.

[0022] Although not specifically shown in the drawings, the cell 10 includes a tab 10T and a lead 10L connected to the tab, as shown in detail in Fig. 1. The arrangement direction of the cell 10 may also be the same as the direction shown in Fig. 1. That is, the cell 10 may be arranged such that the tab 10T is located between a pair of jigs 110 and the lead 10L is located between a pair of bending dies 120. With reference to the drawing, the cell 10 may be arranged such that the lead 10L to be bent by the bending die 120 is located on the left side.

[0023] The pair of jigs 110 includes an upper jig 111 and a lower jig 112. At this time, the pair of jigs 110 may pressurize the tab 10T from both sides of the tab 10T to fix it. Specifically, the upper jig 111 may move down and the lower jig 112 may move up, and these jigs may come into contact with both sides of the tab 10T to pressurize the tab 10T from both sides of the tab 10T to fix it.

[0024] The pair of bending dies 120 includes an upper bending die 121 and a lower bending die 122. At this time, the pair of bending dies 120 may bend the lead 10L by applying pressure from both sides of the lead 10L. Specifically, the upper bending die 121 may be lowered and the lower bending die 122 may be raised, and these bending dies may come into contact with both sides of the lead 10L and bend the lead 10L by applying pressure from both sides of the lead 10L.

[0025] The pair of bending dies 120 may have shapes that interdigitate with each other. In other words, the upper bending die 121 and the lower bending die 122 may have shapes that correspond to each other, for example, in a region where the upper bending die 121 has a concave portion, the lower bending die 122 may have a convex portion having a shape corresponding to the concave portion of the upper bending die 121, and in a region where the upper bending die 121 has a convex portion, the lower bending die 122 may have a concave portion having a shape corresponding to the convex portion of the upper bending die 121. Therefore, the pair of bending dies 120 interdigitate with each other by the upper bending die 121 descending and the lower bending die 122 ascending, and the lead 10L disposed between them can be bent by applying pressure from both sides of the lead 10L.

[0026] The cell 10 may be transported by the transport unit 140, and therefore the cell tab tension measuring device 100 may further include the transport unit 140. The cell 10 being transported by the transport unit 140 may be stopped for a certain period of time in an area where the lead 10L is to be bent, the tab 10T may be fixed by the jig 110, and the lead 10L may be bent by the bending die 120. The transport unit 140 may be a conveyor belt, but is not limited thereto. The transport unit 140 may transport the cell 10 in a direction to protrude and / or enter the drawing.

[0027] A tension gauge 130 is coupled to the cell 10 and measures the tension on the tab 10T when the lead 10L is bent.

[0028] The tension gauge 130 may be disposed on the side opposite to the side where the lead 10L of the cell 10, which is bent by the bending die 120 of the cell 10, is disposed, and may be connected to the cell 10. With reference to the drawing, the tension gauge 130 may be disposed on the right side of the cell 10 and connected to the cell 10. The tension gauge 130 may be connected to the cell 10 and fixed to the cell 10, thereby making it possible to measure the tension applied to the cell 10 connected to the tension gauge 130.

[0029] The direction of the tension applied to the tab 10T may be a direction from the tab 10T toward the lead 10L. In other words, the tension measuring device 130 may measure the tension acting in the direction in which the lead 10L of the tab 10T is connected. With reference to the drawing, the tension measuring device 130 may measure the tension acting in the left direction of the tab 10T.

[0030] The tension measuring device 130 may be any device capable of measuring the tension of the tab 10T when the lead 10L is bent by the bending die 120, including commonly used products, without any restrictions on the type.

[0031] The tension measuring device 130 may be fixed on a conveying part 140 that conveys the cell 10. Therefore, the tension measuring device 130 may be connected to the cell 10 arranged on the conveying part 140 on the conveying part 140, and may measure the tension applied to the tab 10T when the lead 10L is bent.

[0032] On the other hand, when the tab 10T is fixed by the jig 110 and the lead 10L is bent by the bending die 120, tension is applied to the tab 10T. If the tension applied to the tab 10T exceeds a limit value, breakage of the tab 10T may occur.

[0033] The cell tab tension measuring device 100 according to the present invention measures the tension applied to the tab 10T when bending the lead 10L with the tension measuring device 130, thereby preventing breakage of the tab 10T. That is, if the tension measured by the tension measuring device 130 is equal to or greater than the limit value, it can be determined that there is a possibility of breakage of the tab 10T. The limit value of the tension may be the tension value at which breakage of the tab 10T occurs, or may be a value calculated by reflecting a safety factor in the tension at which breakage of the tab 10T occurs. For example, if the tension at which breakage of the tab 10T occurs is 110N, the limit value of the tension may be 110N, or may be 55N reflecting a safety factor of 50%. However, this is merely an example, and the limit value of the tension at which it can be determined that there is a possibility of breakage of the tab 10T may be changed depending on the design of the actual cell 10, etc.

[0034] Meanwhile, the cell 10 may be a dummy cell. The dummy cell may mean a cell that is not an actual product but is manufactured separately for tension measurement. Due to the limited space in which the cell 10 is arranged in the bending equipment including the jig 110 and the bending die 120, it may be difficult to arrange the tension measuring device 130 to be connected to the cell 10, and it may be difficult to measure the tension applied to the tab of the cell, which is an actual product, using the cell tab tension measuring device 100. In such a case, a dummy cell is manufactured and the tension applied to the tab of the dummy cell is measured using the cell tab tension measuring device 100, thereby predicting the tension applied to the tab of the cell, which is an actual product, and preventing the breakage of the tab. However, if there is enough space in which the cell 10 is arranged in the bending equipment, it is of course possible to directly measure the tension applied to the tab of the cell, which is an actual product.

[0035] Factors that may affect the tension applied to the tab 10T when bending the lead 10L include the material of the lead 10L, the sealing temperature of the lead film that seals between the lead 10L and the pouch, the pressure with which the jig 110 presses the tab 10T, the pressure with which the bending die 120 presses the lead 10L, the bending shape (or the shape of the area of ​​the bending die that contacts the lead), etc. Therefore, when measuring the tension applied to the tab of the cell using a dummy cell, it may be preferable to make the material of the lead the same as the material of the lead of the actual cell 10 at the minimum. For example, aluminum (Al), copper (Cu), or an alloy thereof, etc., may be used as the lead material of the dummy cell. It may also be preferable to make the sealing temperature of the lead film during the manufacture of the dummy cell the same as the sealing temperature of the lead film during the manufacture of the actual cell. The pressure applied by the jig 110 and the bending die 120 will not be an issue when using the jig 110 and the bending die 120 that press and bend the actual cell 10.

[0036] The present inventors have fabricated a pouch-type dummy cell in the following manner. However, this is merely an example, and the fabrication method, structure, size, configuration, etc. of the dummy cell are not limited to the following example. Those skilled in the art can fabricate dummy cells of various shapes suitable for the cell tab tension measuring device 100.

[0037] First, a lead was made by cutting aluminum foil into a size of 150mm x 40mm (long side 150mm, short side 40mm) using a cutting machine.

[0038] Next, the polypropylene film was cut with scissors to a size of 105mm x 15mm (long side 105mm, short side 15mm), and the lead film was folded in half to a size of 52.5mm x 15mm (long side 52.5mm, short side 15mm). After that, both ends (the folded side and the ends located on the opposite side) were heated on one side at 160°C for 0.5 seconds using a PP sealing machine (Sanbotech, SK-310K) to seal it.

[0039] After that, the leads were placed between the lead films so that the leads passed between the folded sides of the lead film, and both sides of the tape were heated at 180°C for 3-4 seconds with a sealing machine (UnixHair, UCI-2944FS) to seal the leads and the lead film. Specifically, the leads were placed with their 150mm long side in the horizontal direction, and the lead film was placed with their 15mm short side in the horizontal direction for sealing. At this time, the lead film was placed 30mm away from the end of the leads. Also, the area to be heated was not in direct contact with the sealing machine, but was masked with Teflon tape before heating.

[0040] Next, the aluminum foil was cut into a pouch with a cutting machine to a size of 120mmX90mm (long side 120mm, short side 90mm). Finally, the pouch was folded in half to make it 60mmX90mm, and the leads were placed between the folded pouch so that the lead film was located between the pouch and the leads. The pouch and the leads were then sealed by applying pressure from one end of the pouch to the other at 220℃ for 1-2 seconds to produce a dummy cell. Specifically, the leads were placed with their 150mm long side running horizontally, and the pouch was also sealed with its 90mm long side running horizontally.

[0041] FIG. 3 is a diagram showing a state in which a tension measuring device according to an embodiment of the present invention is connected to a cell.

[0042] As shown in the drawings, one end of the cell 10 may be clamped in the tension measuring device 130 to be connected to the tension measuring device 130. If necessary, the cell 10 may be fixed to the tension measuring device 130 by a separate screw or the like.

[0043] Also, as described above, the tension gauge 130 may be disposed on the side opposite to the side where the lead 10L of the cell 10 to be bent by the bending die 120 is disposed, and may be connected to the cell 10. The tension gauge 130 may be connected to the cell 10 and fixed to the cell 10, thereby making it possible to measure the tension applied to the cell 10 connected to the tension gauge 130.

[0044] Meanwhile, a method for measuring cell tab tension according to an embodiment of the present invention includes the steps of fixing the tab 10T, bending the lead 10L, and measuring the tension applied to the tab 10T when the lead 10L is bent.

[0045] In the step of fixing the tab 10T, the tab 10T may be fixed by applying pressure to both sides of the tab 10T. At this time, the tab 10T may be fixed by the pair of jigs 110 described above.

[0046] The step of bending the leads 10L may be performed after the step of fixing the tabs 10T. In the step of bending the leads 10L, the leads 10L may be bent by applying pressure to both sides of the leads 10L. At this time, the leads 10L may be bent by the pair of bending dies 120 described above.

[0047] In the step of measuring the tension applied to the tab 10T when the lead 10L is bent, the tension measured may be tension applied in a direction from the tab 10T to the lead 10L. In other words, the tension measured in the step of measuring the tension may be tension acting in a direction in which the tab 10T is connected to the lead 10L. At this time, the tension applied to the tab 10T may be measured by the tension measuring device 130 described above.

[0048] Also, the cell tab tension measuring method according to the embodiment of the present invention may further include the step of transporting the cell 10. At this time, the cell 10 may be transported by the transport unit 140 described above.

[0049] Other details regarding the cell tab tension measuring method are substantially the same as those described above in the description of the cell tab tension measuring device according to one embodiment of the present invention, so detailed description will be omitted.

[0050] Although an embodiment of the present invention has been described above by way of example, it is not intended that the present invention be limited to the above embodiment. Those skilled in the art may appropriately modify and implement an embodiment of the present invention by omitting, changing, or replacing all or part of the configuration of the present invention or adding other configurations, without departing from the technical spirit of the present invention, by referring to this specification and the attached drawings.

[0051] In this specification, the terms "first", "second", etc. are used to distinguish elements from one another, and do not imply a priority order or an absolute order between elements. A first element in one part of this specification may be referred to as a second element in another part of this specification.

[0052] The terms and expressions in this specification should be interpreted broadly and not in a restrictive sense. In this specification, the term "comprise" does not exclude the presence or addition of one or more other components other than the mentioned components.

[0053] In this specification, the singular forms include the plural forms unless the context clearly indicates otherwise.

[0054] Each embodiment described as an example in this specification can be combined with each other, and unless inconsistent, the content described in a particular embodiment can be equally applied to other embodiments even if not described in other embodiments. [Explanation of symbols]

[0055] 10: Cell 10B: Body 10T:Tab 10L: Lead 100: Cell tab tension measuring device 110, 111, 112: Jig 120, 121, 122: Bending dies 130:Tension measuring device 140:Transfer section

Claims

1. 1. A cell tab tension measurement device for a cell including a tab and a lead connected to the tab, comprising: A pair of jigs for fixing the tabs; a pair of bending dies for bending the leads; and a tension gauge coupled to the cell for measuring the tension on the tab when the lead is bent.

2. 2. The cell tab tension measuring device according to claim 1, wherein the tension measuring device measures a tension acting in a direction in which the lead of the tab is connected.

3. 2. The cell tab tension measuring device according to claim 1, wherein the pair of jigs pressurize the tab from both sides to fix the tab.

4. 2. The cell tab tension measuring device according to claim 1, wherein the pair of bending dies pressurize the leads from both sides to bend the leads.

5. The cell tab tension measuring device according to claim 1 , wherein the pair of bending dies have shapes that interlock with each other.

6. The cell tab tension measuring device according to claim 1 , wherein the tension measuring device is arranged on the opposite side of the cell to the side on which the leads are arranged, and is connected to the cell.

7. The cell tab tension measurement device of claim 1 , wherein the cell is a dummy cell.

8. A cell tab tension measurement method for a cell including a tab and a lead connected to the tab, using the cell tab tension measurement device of claim 1, comprising: fixing the tabs by the pair of jigs; bending the leads with the pair of bending dies; and measuring the tension on said tab when said lead is bent by said tension gauge.

9. 9. The cell tab tension measuring method of claim 8, wherein the step of measuring the tension applied to the tab when the lead is bent measures the tension acting in a direction in which the tab is connected to the lead.

10. 10. The method of claim 8, wherein the step of bending the lead is performed after the step of fixing the tab.

11. A method for measuring cell tab tension for a cell including a tab and a lead coupled to the tab, comprising: securing the tab; bending the leads; and measuring the tension on the tab as the lead is bent; In the step of fixing the tab, the tab is fixed by applying pressure to both sides of the tab, In the step of bending the lead, the lead is bent by applying pressure to both sides of the lead.

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