How to bend battery leads

Abstract

The present invention relates to a method for bending battery leads, and more particularly to a method for bending battery leads that can minimize deformation of the battery during the bending process. A lead bending method according to the present invention is a method for bending a first lead that protrudes from a battery cell stack located on one side in a first direction of a bus bar frame assembly, which includes a bus bar and a bus bar frame housing the bus bar, to the other side in a first direction of the bus bar frame assembly, comprising the steps of: positioning the bending tool on one side in a second direction which is perpendicular to the first direction of the first lead; moving the bending tool to the other side in the second direction to pressurize the first lead and tilt the first lead to the other side in the second direction; moving the bending tool to one side in the first direction to pressurize the first lead and bring the first lead into close contact with the bus bar frame assembly; moving the bending tool to the other side in the second direction to slide it relative to the first lead; and moving the bending tool to the other side in the first direction.

Description

Technical Field

[0001] The present invention relates to a method for bending a lead of a battery.

Background Art

[0002] A secondary battery can be charged and discharged, and is widely used in mobile devices such as digital cameras, mobile phones, and notebook personal computers. In particular, in recent years, it has attracted attention as an energy source for electric vehicles, energy storage systems (ESS), etc. On the other hand, in electric vehicles and energy storage devices, as higher power and larger capacity are required, medium- to large-sized battery devices such as battery modules in which a large number of secondary batteries are housed inside a housing and battery packs including a large number of battery modules are widely used.

[0003] Medium- to large-sized battery devices are preferably manufactured with the smallest possible size and weight, so prismatic battery cells, pouch-type battery cells, etc. with a high integration density and a small capacity-to-weight ratio are mainly used as battery cells (unit cells). In particular, pouch-type battery cells that use an aluminum laminate sheet or the like as an exterior member have recently attracted much attention due to advantages such as a small weight, a low manufacturing cost, and easy deformation of the form.

[0004] On the other hand, in order to electrically connect the battery cells constituting such medium- to large-sized battery devices, the leads of the battery cells are welded to a bus bar. Before welding the leads of the battery cells to the bus bar, the leads of the battery cells are bent so as to be in close contact with the bus bar.

[0005] By the way, when bending by a normal bending method, various problems such as deformation of the battery and deterioration of the bending quality may occur.

Summary of the Invention

Problems to be Solved by the Invention

[0006] This invention was devised in consideration of the aforementioned problems, and relates to a method for bending battery leads, with a particular objective of providing a method for bending battery leads that can minimize deformation of the battery during the bending process. [Means for solving the problem]

[0007] A battery lead bending method according to one embodiment of the present invention is a method for bending a first lead that protrudes from a battery cell stack located on one side in a first direction of a busbar frame assembly, which includes a busbar and a busbar frame housing the busbar, to the other side in the first direction of the busbar frame assembly, The bending tool includes the steps of: positioning the bending tool on one side of a second direction which is perpendicular to the first direction of the first lead; moving the bending tool to the other side of the second direction to pressurize the first lead and tilt it to the other side of the second direction; moving the bending tool to one side of the first direction to pressurize the first lead and bring it into close contact with the busbar frame assembly; moving the bending tool to the other side of the second direction to slide it relative to the first lead; and moving the bending tool to the other side of the first direction.

[0008] The step of positioning the bending tool on one side of the first lead in the second direction may involve the distance between the bending tool and the busbar frame assembly along the first direction being half the length of the first lead protruding to the other side of the busbar frame assembly in the first direction.

[0009] By moving the bending tool to the other side in the second direction, the bending tool can be moved to a position where, in the step of applying pressure to the first lead and tilting the first lead to the other side in the second direction, the tip surface of the bending tool and the starting point of bending of the first lead overlap at least partially.

[0010] In the step of applying pressure to the first lead and tilting it to the other side of the second direction by moving the bending tool to the other side of the second direction, the bending tool can be moved to a position where the center of the tip surface of the bending tool along the second direction coincides with the starting point of bending the first lead.

[0011] In the step of pressing the first lead to bring the first lead into close contact with the busbar frame assembly by moving the bending tool to one side in the first direction, the bending tool may press the busbar frame assembly so that the busbar frame assembly is elastically deformed to one side in the first direction.

[0012] In the step of moving the bending tool to the other side in the first direction, the busbar frame assembly can be elastically restored at least partially as the bending tool retracts to the other side in the first direction.

[0013] The lead bending method involves moving the bending tool to the other side of the first direction, The process may further include bending a second lead that protrudes from the other side of the first lead in the second direction to the other side of the busbar frame assembly in the first direction.

[0014] The step of bending a second lead that protrudes from the other side of the first lead in a second direction to the other side of the busbar frame assembly in a first direction may further include the steps of positioning a bending tool on the other side of the second lead in a second direction; moving the bending tool to one side in a second direction to pressurize the second lead and tilt it to one side in a second direction; moving the bending tool to one side in a first direction to pressurize the second lead and bring it into close contact with the busbar frame assembly; and further moving the bending tool to one side in a second direction to slide it relative to the first lead.

[0015] In the step of positioning the bending tool on the other side of the second lead in the second direction, the distance between the bending tool and the busbar frame assembly along the first direction may be greater than the distance between the end of the first lead, generated by the elastic restoration of the first lead, and the busbar frame assembly along the first direction.

[0016] The length of the first lead protruding from the busbar frame assembly may be less than the distance between the first lead and the second lead.

[0017] The length of the first lead protruding from the busbar frame assembly may be less than the distance between the first lead and the second lead minus half the width of the bending tool along the second direction.

[0018] Bending tools can be insulated. [Effects of the Invention]

[0019] According to one aspect of the present invention, the bending tool can reduce the force required to bend the first lead while simultaneously providing stability during the bending process. The force required to bend the first lead may be proportional to the minimum stress required to bend the first lead divided by the distance between the bending tool and the point where the first lead is bent. Therefore, the closer the bending tool is to the busbar frame assembly, the closer it is to the point where the first lead is bent, and the greater the force the bending tool can exert to bend the first lead. As a result, the busbar frame assembly may be pushed by the repulsive force of the first lead during the bending process. However, the further the bending tool is from the busbar frame assembly, the higher the risk that the first lead may deviate from the constraint of the bending tool during the bending process. Therefore, when the above-mentioned stage is reached, the bending tool can reduce the force required to bend the first lead while simultaneously providing stability.

[0020] According to another aspect of the present invention, when pressing the first lead to bring it into close contact with the bus bar frame assembly, since the point where the first lead is bent is pressed by the tip surface of the bending tool, the first lead can be easily bent. In particular, when the center along the second direction of the tip surface presses the point where the first lead is bent, the first lead can be bent most easily. Therefore, due to the restoring force of the first lead, the problem that the first lead floats from the bus bar frame assembly can be minimized.

[0021] According to still another aspect of the present invention, it is possible to prevent the first lead from being separated due to the elastic restoration of the bus bar frame assembly.

[0022] According to still another aspect of the present invention, the first lead and the second lead can be bent in a direction approaching each other, and in particular, as a result, they can be provided such that at least one region overlaps. This can contribute to preventing deformation of the battery cell.

[0023] According to still another aspect of the present invention, when pressing the second lead to tilt the second lead, the elastically restored first lead can be pushed by the second lead and come into close contact with the bus bar frame assembly again.

Brief Description of the Drawings

[0024] [Figure 1] It shows a battery cell laminate including leads bent by the lead bending method according to the present invention. [Figure 2] It is a diagram showing a battery cell laminate and a bus bar frame assembly including leads bent by the lead bending method according to the present invention. [Figure 3] It is a diagram showing a bending tool and a lead used in the lead bending method according to the present invention. [Figure 4] It is a diagram showing the steps included in the lead bending method according to the present invention. [Figure 5] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 6] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 7] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 8] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 9] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 10] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 11] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 12] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 13] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 14] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 15] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 16] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 17] A diagram showing the steps included in the method for bending leads according to the present invention. [Figure 18] A diagram showing the steps included in the method for bending leads according to the present invention.

Embodiments for Carrying Out the Invention

[0025] Prior to a detailed description of the present invention, terms and words used herein and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather should be interpreted in a manner consistent with the technical idea of ​​the present invention, based on the principle that inventors may appropriately define terms as concepts in order to best describe their invention. Accordingly, the embodiments described herein and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not substitute for the entire technical idea of ​​the present invention, and it should be understood that, at the time of filing, there may be a variety of equivalents and variations that can substitute for them.

[0026] The same reference numerals or symbols in the drawings accompanying this specification indicate parts or components that perform substantially the same function. For convenience of explanation and understanding, the same reference numerals or symbols may be used to describe different embodiments. That is, even if components with the same reference numerals are illustrated in multiple drawings, not all of the drawings represent a single embodiment.

[0027] In the following descriptions, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as “contains” or “constitutes” are intended to specify that there are features, figures, stages, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preemptively exclude the existence or possibility of adding one or more other features, figures, stages, operations, components, parts, or combinations thereof.

[0028] Furthermore, in the following explanation, terms such as "top," "upper," "lower," "bottom," "side," "front," and "rear" are used based on the direction shown in the drawing, and it should be made clear beforehand that they may be expressed differently if the direction of the object changes.

[0029] Furthermore, within this specification and the claims, terms including ordinal numbers, such as "first," "second," etc., may be used to distinguish between components. Such ordinal numbers are used to distinguish identical or similar components from one another, and the use of such ordinal numbers should not restrict the meaning of the terms. For example, the order of use or arrangement of components combined with such ordinal numbers should not be restricted by the numbers. If necessary, the ordinal numbers may be substituted for each other.

[0030] Embodiments of the present invention will be described below with reference to the attached drawings. However, the concept of the present invention is not limited to the embodiments presented. For example, a person of ordinary skill who understands the concept of the present invention may propose other embodiments that fall within the scope of the present invention through the addition, modification, or deletion of components, and these too can be said to fall within the scope of the present invention. The shapes and sizes of elements in the drawings may be exaggerated for clearer explanation.

[0031] Figure 1 shows a battery cell stack 20 including leads 201 and 202 that are bent by the lead bending method according to the present invention.

[0032] Referring to Figure 1, the battery cell stack 20 can include multiple battery cells 200. The battery cell stack 20 can have multiple battery cells 200 stacked in one direction. The battery cells 200 may be pouch cells.

[0033] A pouch battery cell may include an electrode assembly, an electrolyte, and a pouch casing. The electrode assembly may be formed by folding or winding a laminate including a first electrode, a second electrode, and a separator membrane. The pouch battery cell may include a first lead 201 electrically connected to the first electrode of the electrode assembly and protruding from the pouch casing, and a second lead 202 electrically connected to the second electrode of the electrode assembly and protruding from the pouch casing. The first lead 201 and the second lead 202 may protrude in both directions, as shown in Figure 1, or they may protrude in one direction. The first lead 201 may be made of copper. The first lead 201 may be negative. The second lead 202 may be made of aluminum. The second lead 202 may be positive.

[0034] Figure 2 is a drawing showing a battery cell stack 20 and a busbar frame assembly 10 including leads bent by the lead bending method according to the present invention.

[0035] Referring to Figure 2, the busbar frame assembly 10 may include a busbar 110 and a busbar frame 130.

[0036] Multiple battery cells 200 constituting the battery cell stack 20 can be electrically connected by busbars 110. Multiple battery cells 200 constituting the battery cell stack 20 can be connected in series and / or parallel depending on the connection method of the busbars 110. Busbars 110 may be provided between each of the multiple battery cells 200. Busbars 110 may be in contact with the leads of the battery cells 200. The busbars 110 and the leads of the battery cells 200 may be joined by welding. Busbars 110 may include a conductive metal.

[0037] The busbar frame 130 may accommodate the busbar 110. The busbar frame 130 may be provided on one side and / or the other side of the battery cell stack 20. The busbar frame 130 may be provided in the direction in which the leads of the battery cells 200 protrude. The busbar frame 130 may include an electrically insulating material. The busbar frame 130 may accommodate a first external terminal T1 and a second external terminal T2.

[0038] As shown in Figure 2, welding of the leads to the busbar 110 is necessary for the battery cell stack 20 and the busbar 110 to be stably bonded. For welding the leads to the busbar 110, the leads must be bent at an angle of approximately 90 degrees so that they are in surface contact with the busbar 110 or the busbar frame.

[0039] The following sections will explain the lead bending method in more detail using Figures 3 through 18.

[0040] Figure 3 is a diagram showing a bending tool 300 and a first lead 201 used in the lead bending method according to the present invention.

[0041] Referring to Figure 3, the method for bending the first lead 201 using the bending tool 300 will be outlined.

[0042] Figure 3 shows the bending tool 300 positioned on one side of the first lead 201. The bending tool 300 can move to the other side of the first lead 201 to bend it. After bending the first lead 201, the bending tool 300 can apply pressure to the first lead 201 with its tip surface S to bring the first lead 201 into close contact with the busbar 110.

[0043] The bending tool 300 may be insulated. The bending tool 300 may be insulated to prevent the risk of short circuits between products. For example, the bending tool 300 may be made of a material such as ceramic or Peek.

[0044] The bending tool 300 may be larger than the width of the lead in order to apply uniform pressure across the entire width of the lead. The length of the tip surface S of the bending tool 300 along the Z axis may also be greater than the width of the lead.

[0045] The width of the tip surface S of the bending tool 300 along the direction aligned with the Y axis may be 5 mm or more. If the length of the tip surface S of the bending tool 300 along the Y axis is 5 mm or less, it may be difficult to align the starting point of bending of the lead 201 and the tip surface S of the bending tool 300 with respect to the Y axis so that they overlap at least partially, which may result in a smaller pressure point for the bending tool 300 and cause damage to the lead 201 or the busbar frame assembly 10.

[0046] The edges of the bending tool 300 can be rounded. This can prevent the problem of the lead being damaged by the edges of the bending tool 300 during contact with the lead.

[0047] Figures 4 to 18 are diagrams illustrating the steps included in the lead bending method according to the present invention. In Figures 4 to 18, the busbar frame 130 housing the busbar 110 and the battery cell stack 20 are omitted for simpler explanation of the lead bending method. The first lead 201 and the second lead 202 in Figures 4 to 18 may represent the leads of adjacent battery cells 200. In Figures 4 to 18, the busbar 110 shown in the positive and negative directions of the Y-axis are cross-sections of a single busbar 110, which may be cross-sections of a single busbar 110 with a substantially open center. Thus, adjacent battery cells 200 can be electrically connected by the busbar 110. The lead bending method illustrated in Figures 4 to 18 may be performed in one direction and / or both directions in which the leads of the battery cell stack 20 protrude.

[0048] The lead bending method according to the present invention may be a method for bending a first lead 201 that protrudes from a battery cell stack 20 provided on one side of the busbar frame assembly 10 in a first direction (positive direction of the X axis) to the other side of the busbar frame assembly 10 in a first direction (negative direction of the X axis). The battery cell stack 20 may be a stack of multiple battery cells 200 arranged in a second direction (direction aligned with the Y axis) which is perpendicular to the first direction.

[0049] The lead bending method may include a step of positioning the bending tool 300 on one side of the first lead 201 in a second direction (positive Y-axis direction) that is perpendicular to the first direction (direction aligned with the X-axis). Figure 4 shows the bending tool 300 positioned on the other side of the first lead 201 in the second direction (negative Y-axis direction), and Figures 5 and 6 show the bending tool 300 positioned on one side of the first lead 201 in the second direction (positive Y-axis direction).

[0050] The lead bending method may include a step of pressing the first lead 201 and tilting it in the other direction of the second direction (negative direction of the Y-axis) by moving the bending tool 300 to the other side of the second direction (negative direction of the Y-axis). Figure 7 shows the bending tool 300 pressing the first lead 201 and tilting it in the other side of the second direction (negative direction of the Y-axis).

[0051] The lead bending method may include a step of pressing the first lead 201 to make it tightly attached to the busbar frame assembly 10 by moving the bending tool 300 to one side in a first direction (the positive direction of the X axis). Figure 8 shows the first lead 201 being pressed to make it tightly attached to the busbar frame assembly 10 by moving the bending tool 300 to one side in a first direction (the positive direction of the X axis).

[0052] The lead bending method may include a step of moving the bending tool 300 to the other side of the second direction (the negative direction of the Y-axis) and sliding it against the first lead 201. Figure 10 shows the bending tool 300 being moved to the other side of the second direction (the negative direction of the Y-axis) and sliding against the first lead 201.

[0053] The lead bending method may include a step of moving the bending tool 300 to the other side of the first direction (the negative direction of the X-axis). Figure 11 shows the bending tool 300 moved to the other side of the first direction (the negative direction of the X-axis).

[0054] Referring again to Figure 6, in the step of positioning the bending tool 300 on one side of the first lead 201 in the second direction (positive direction of the Y axis), the distance (X / 2) between the bending tool 300 and the busbar frame assembly 10 along the first direction may be approximately half the length (X) that the first lead 201 protrudes to the other side of the busbar frame assembly 10 in the first direction (negative direction of the X axis).

[0055] According to this step of the present invention, in the step of tilting the first lead 201 to the other side of the second direction (the negative direction of the Y-axis), the bending tool 300 can reduce the force required to tilt the first lead 201 while simultaneously providing stability in the tilting process. The force required to tilt the first lead 201 can be proportional to the minimum stress required to bend the first lead 201 divided by the distance between the bending tool 300 and the point where the first lead 201 is bent. Therefore, the closer the bending tool 300 is to the busbar frame assembly 10, the closer the bending tool 300 is to the point where the first lead 201 is bent, and the greater the force that the bending tool 300 applies to tilt the first lead 201. In the process of tilting the first lead 201, the busbar frame assembly 10 may be pushed by the repulsive force of the first lead 201. Conversely, the greater the distance between the bending tool 300 and the busbar frame assembly 10, the greater the risk that the first lead 201 may deviate from the constraints of the bending tool 300 during the process of the bending tool 300 tilting the first lead 201. Therefore, setting the distance between the bending tool 300 and the busbar frame assembly 10 along the first direction at the above-described stage can reduce the force required for the bending tool 300 to tilt the first lead 201 while simultaneously providing operational stability.

[0056] Referring again to Figure 7, in the step of applying pressure to the first lead 201 and tilting it in the other direction of the second direction (negative direction of the Y axis) by moving the bending tool 300 to the other side of the second direction (negative direction of the Y axis), the bending tool 300 can be moved to a position where the tip surface S of the bending tool 300 and the starting point of bending of the first lead 201 overlap at least partially. That is, the bending tool 300 can be moved until the tip surface S of the bending tool 300 and the starting point of bending of the first lead 201 overlap at least partially in the first direction. Here, "overlapping in the first direction" means that the two components are positioned so that they overlap each other when viewed from the first direction.

[0057] As the bending tool 300 moves to the other side of the second direction (the negative direction of the Y-axis), the first lead 201 is pressurized and tilted to the other side of the second direction (the negative direction of the Y-axis). At this stage, the center of the tip surface S of the bending tool 300 along the second direction (the direction aligned with the Y-axis) may be moved to a position that coincides with the starting point of bending of the first lead 201.

[0058] The starting point for bending the first lead 201 may be the starting point where the first lead 201 protrudes from the busbar frame assembly 10.

[0059] According to this step of the present invention, in the step of pressurizing the first lead 201 to bring it into close contact with the busbar frame assembly 10, the point at which the first lead 201 is bent is pressed by the tip surface S of the bending tool 300, so that the first lead 201 can be easily bent. In particular, the first lead 201 can be bent most easily when the center of the tip surface S along the second direction pressurizes the point at which the first lead 201 is bent. Therefore, the restoring force of the first lead 201 can minimize the problem of the first lead 201 lifting away from the busbar frame assembly 10.

[0060] Referring again to Figure 8, in the step of pressing the first lead 201 to bring it into close contact with the busbar frame assembly 10 by moving the bending tool 300 to one side in the first direction (positive X-axis), the bending tool 300 can press the busbar frame assembly 10 so that the busbar frame assembly 10 is elastically deformed to one side in the first direction (positive X-axis). The amount of movement (h) of the elastically deformed busbar frame assembly 10 may be less than or equal to the thickness of the first lead 201. For example, the busbar frame assembly 10 can be elastically deformed by approximately 0.5 mm to 1 mm by the pressurization of the bending tool 300.

[0061] At this stage, the first lead 201 must be bent so that it does not separate from the busbar frame assembly 10. If the bending tool 300 is moved too quickly, the first lead 201 may not be properly fired and may elastically restore itself again. Therefore, a speed of the bending tool 300 that minimizes the restoration of the first lead 201 can be applied. A step to determine this speed may be added before the bending process.

[0062] Furthermore, if the bending process is performed simultaneously in both directions in which the leads of the battery cell stack 20 protrude, the speed of the bending tool can be matched to prevent the battery cell 200 from being pushed or twisted to one side.

[0063] Referring again to Figure 9, the step of moving the bending tool 300 to the other side of the first direction (the negative direction of the X axis) may further include a step of retracting the bending tool 300 to the other side of the first direction (the negative direction of the X axis) so that the busbar frame assembly 10 is elastically restored to at least a portion. For example, the bending tool 300 may retract to the other side of the first direction (the negative direction of the X axis) by the thickness of the first lead 201. Or, the bending tool 300 may retract to the other side of the first direction (the negative direction of the X axis) by half the thickness of the first lead 201.

[0064] The retraction process of the bending tool 300 minimizes deformation of the first lead 201 due to subsequent movement of the bending tool 300 in the second direction. That is, if the bending tool 300 moves to the other side of the second direction (negative direction of the Y-axis) while excessively pressurizing the first lead 201, a portion of the first lead 201 that is released from the pressurization by the bending tool 300 may spread out without making close contact with the busbar frame assembly 10, or the bending may loosen. Therefore, the retraction step of the bending tool 300 allows the bending tool 300 to slide while maintaining firm contact with the first lead 201.

[0065] Referring again to Figures 12 to 18, the lead bending method may further include the step of bending the second lead 202 that protrudes from the other side of the first direction (negative direction of the Y axis) of the first lead 201 to the other side of the first direction (negative direction of the X axis) of the busbar frame assembly 10.

[0066] In the present invention, the first lead 201 and the second lead 202 may be bent toward each other, and in particular may be arranged such that at least one area overlaps as a result. This may help prevent deformation of the battery cell 200.

[0067] The lead bending method involves bending the second lead 202, which protrudes from the other side of the first direction (negative direction of the Y-axis) of the first lead 201 to the other side of the first direction (negative direction of the X-axis) of the busbar frame assembly 10. This involves positioning the bending tool 300 on the other side of the second direction (negative direction of the Y-axis) of the second lead 202, and then moving the bending tool 300 to one side of the second direction (positive direction of the Y-axis) to bend the second lead 202. The process may include steps of applying pressure to tilt the second lead 202 to one side in the second direction (positive Y-axis direction), moving the bending tool 300 to one side in the first direction (positive X-axis direction) to apply pressure to the second lead 202 and bring it into close contact with the busbar frame assembly 10, and further moving the bending tool 300 to one side in the second direction (positive Y-axis direction) to slide it relative to the first lead 201. This step can be performed in a manner similar to the method of bending the first lead 201 described above.

[0068] After the bending of the first lead 201 is complete, the bending tool 300 may move to the other side of the second direction (negative direction of the Y-axis), as shown in Figure 12, and then move to one side of the first direction (positive direction of the X-axis), as shown in Figure 13, in order to bend the second lead 202.

[0069] Referring to Figure 13, in the step of positioning the bending tool 300 on the other side of the second direction of the second lead 202 (negative direction of the Y-axis), the distance (y2) between the bending tool 300 and the busbar frame assembly 10 along the first direction (direction aligned with the X-axis) may be greater than the distance (y1) between the end of the first lead 201 generated by the elastic restoration of the first lead 201 and the busbar frame assembly 10 along the first direction (direction aligned with the X-axis).

[0070] According to this step of the present invention, in the step of pressurizing the second lead 202 to tilt it to one side in the second direction (the positive direction of the Y-axis), the elastically restored first lead 201 may be pushed by the second lead 202 and come into contact with the busbar frame assembly 10 again. This is because if the bending tool 300 is moved to one side in the second direction (the positive direction of the Y-axis) while the distance along the first direction between the bending tool 300 and the busbar frame assembly 10 is smaller than the distance along the first direction between the end of the first lead 201 and the busbar frame assembly 10, which is generated by the elastic restoration of the first lead 201, pressurizing the second lead 202 may cause the elastically restored first lead 201 to separate from or be damaged by the second lead 202.

[0071] Referring again to Figures 13 to 18, the method for bending the first lead 201 described above will be applied to the method for bending the second lead 202 for a brief explanation.

[0072] In the step of positioning the bending tool 300 on the other side of the second direction of the second lead 202 (negative direction of the Y-axis), the distance between the bending tool 300 and the busbar frame assembly 10 along the first direction may be half the length of the second lead 202 protruding to the other side of the busbar frame assembly 10 in the first direction (negative direction of the X-axis).

[0073] In the step of applying pressure to the second lead 202 and tilting it to one side of the second direction (positive direction of the Y-axis) by moving the bending tool 300 to one side of the second direction (positive direction of the Y-axis), the bending tool 300 can be moved to a position where the tip surface S of the bending tool 300 and the starting point of bending of the second lead 202 overlap at least partially. That is, the bending tool 300 can be moved until the tip surface S of the bending tool 300 and the starting point of bending of the second lead 202 overlap at least partially with respect to the Y-axis.

[0074] In the step of applying pressure to the second lead 202 and tilting the second lead 202 to one side of the second direction (the positive direction of the Y-axis) by moving the bending tool 300 to one side of the second direction (the positive direction of the Y-axis), the bending tool 300 may be moved to a position where the center of the tip surface S of the bending tool 300 along the second direction (the direction aligned with the Y-axis) coincides with the starting point of bending the second lead 202.

[0075] The starting point for bending the second lead 202 may be the point where the second lead 202 begins to protrude from the busbar frame assembly 10.

[0076] In the step of pressing the second lead 202 to make it tightly adhere to the busbar frame assembly 10 by moving the bending tool 300 to one side in the first direction (the positive direction of the X axis), the busbar frame assembly 10 may be elastically deformed to one side in the first direction (the positive direction of the X axis) as the bending tool 300 presses on the busbar frame assembly 10. For example, the busbar frame assembly 10 may be elastically deformed by up to the combined thickness of the first lead 201 and the second lead 202.

[0077] In the step of moving the bending tool 300 to the other side of the first direction (the negative direction of the X-axis), the bending tool 300 may be retracted to the other side of the first direction (the negative direction of the X-axis) so that the busbar frame assembly 10 is elastically restored to at least a portion of its original shape. For example, the bending tool 300 may be retracted to the other side of the first direction (the negative direction of the X-axis) by an amount equal to the combined thickness of the first lead 201 and the second lead 202. Alternatively, the bending tool 300 may be retracted to half the combined thickness of the first lead 201 and the second lead 202.

[0078] Referring to Figure 14, the length of the first lead 201 protruding from the busbar frame assembly 10 may be less than the distance between the first lead 201 and the second lead 202. In particular, the length of the first lead 201 protruding from the busbar frame assembly 10 may be less than the distance between the first lead 201 and the second lead 202 minus half of the width (t) of the bending tool along the second direction.

[0079] According to this configuration of the present invention, when the second lead 202 is bent after the first lead 201 has been bent, it is possible to prevent the end of the first lead 201 from being damaged or wrinkled by the bending of the second lead 202.

[0080] In particular, when the second lead 202 is bent while the first lead 201 is not in complete contact with the busbar frame assembly 10, the first lead 201 may interfere with the bending of the second lead 202, and this must be prevented. For example, if the length of the first lead 201 protruding from the busbar frame assembly 10 is greater than the distance between the first lead 201 and the second lead 202 minus half the width (t) of the bending tool along the second direction, the second lead 202 may not be bent sufficiently and may interfere with the first lead 201, which may cause the first lead 201 to be subjected to a large compressive force in the longitudinal direction and be damaged.

[0081] As described above, the present invention has been described in part with reference to the accompanying drawings, but it will be clear to those skilled in the art that many diverse and obvious modifications are possible without departing from the scope of the invention. Accordingly, the scope of the invention should be interpreted as being defined by the claims, which are written to include such many modifications. [Explanation of Symbols]

[0082] 10: Busbar Frame Assembly 110: Bus bar 130: Busbar Frame 20: Battery cell stack 200: Battery cell 201: First lead 202: Second lead 300: Bending Tools S: Tip surface T1: First terminal T2: Second terminal

Claims

1. A method for bending a first lead that protrudes from a battery cell stack located on one side in a first direction of a busbar frame assembly, which includes a busbar and a busbar frame housing the busbar, to the other side in the first direction of the busbar frame assembly, The steps include positioning the bending tool on one side of the first lead in a second direction which is perpendicular to the first direction, The bending tool is moved to the other side in the second direction, thereby pressurizing the first lead and tilting the first lead to the other side in the second direction. The steps include moving the bending tool to one side in the first direction to pressurize the first lead and bring the first lead into close contact with the busbar frame assembly, The steps include moving the bending tool to the other side in the second direction and sliding it against the first lead, A method for bending a lead, comprising the step of moving the bending tool to the other side in the first direction.

2. The step of positioning the bending tool on one side of the first lead in the second direction is: The lead bending method according to claim 1, characterized in that the distance along the first direction between the bending tool and the busbar frame assembly is half the length of the first lead that protrudes from the busbar frame assembly to the other side in the first direction.

3. In the step of moving the bending tool to the other side in the second direction, thereby pressurizing the first lead and tilting the first lead to the other side in the second direction, A method for bending a lead according to claim 1 or 2, characterized in that the bending tool is moved to a position where the tip surface of the bending tool and the starting point of bending the first lead overlap at least partially.

4. In the step of moving the bending tool to the other side in the second direction, thereby pressurizing the first lead and tilting the first lead to the other side in the second direction, A method for bending a lead according to claim 1 or 2, characterized in that the bending tool is moved to a position where the center of the tip surface of the bending tool along the second direction coincides with the starting point of bending the first lead.

5. In the step of moving the bending tool to one side in the first direction to pressurize the first lead and bring the first lead into close contact with the busbar frame assembly, The lead bending method according to claim 1 or 2, characterized in that the bending tool presses the busbar frame assembly so that the busbar frame assembly is elastically deformed to one side in the first direction.

6. In the step of moving the bending tool to the other side in the first direction, The lead bending method according to claim 5, characterized in that the busbar frame assembly is elastically restored at least partially by the retraction of the bending tool to the other side in the first direction.

7. The method for bending the lead is: From the step of moving the bending tool to the other side in the first direction, The lead bending method according to claim 1 or 2, further comprising the step of bending a second lead that protrudes from the other side of the first lead in the second direction to the other side of the busbar frame assembly in the first direction.

8. The step of bending the second lead that protrudes from the other side of the first lead in the second direction to the other side of the busbar frame assembly in the first direction is: The steps include positioning the bending tool on the other side of the second lead in the second direction, The steps include moving the bending tool to one side in the second direction to pressurize the second lead and tilt the second lead to one side in the second direction, The steps include moving the bending tool to one side in the first direction to pressurize the second lead and bring the second lead into close contact with the busbar frame assembly, A method for bending a lead according to claim 7, characterized by comprising the step of further moving the bending tool to one side in the second direction and sliding it with respect to the first lead.

9. In the step of positioning the bending tool on the other side of the second lead in the second direction, The lead bending method according to claim 8, characterized in that the distance along the first direction between the bending tool and the busbar frame assembly is greater than the distance along the first direction between the end of the first lead and the busbar frame assembly generated by the elastic restoration of the first lead.

10. The first lead mentioned above is The lead bending method according to claim 7, characterized in that the length protruding from the busbar frame assembly is less than the distance between the first lead and the second lead.

11. The first lead mentioned above is The lead bending method according to claim 10, characterized in that the length protruding from the busbar frame assembly is less than the distance between the first lead and the second lead minus half the width of the bending tool along the second direction.

12. The method for bending a lead according to claim 1 or 2, characterized in that the bending tool is insulated.

Images