KR-20260063467-A - TOP CAP WELDING APPARATUS OF CYLINDRICAL BATTERY CELL AND TOP CAP WELDING METHOD OF CYLINDRICAL BATTERY CELL USING THE SAME

KR20260063467AKR 20260063467 AKR20260063467 AKR 20260063467AKR-20260063467-A

Abstract

The present invention relates to a top cap welding device for a cylindrical battery cell and a top cap welding method for a cylindrical battery cell using the same, comprising: a conveying unit for conveying a cylindrical battery case containing an electrode assembly in which an electrode tab is exposed to the outside; a pressing unit located at the front of the battery case and pressing the battery case; a supporting unit located at the rear of the battery case and provided to support the battery case; a top cap holder for positioning a top cap at the rear of the electrode tab; a top cap supporting unit provided to support the rear of the top cap; and a welding unit for welding the electrode tab and the top cap; wherein the pressing unit presses the battery case while controlling the angle between the electrode tab and the top cap or the distance between the electrode tab and the top cap so that the electrode tab corresponds to the position of the top cap.

Inventors

이수호

Assignees

주식회사 엘지에너지솔루션

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (15)

A transfer unit for transferring a cylindrical battery case containing an electrode assembly in which the electrode tabs are exposed to the outside; A pressurizing part located at the front of the battery case and pressurizing the battery case; A support member located at the rear of the battery case and provided to support the battery case; A top cap holder positioning the top cap at the rear of the electrode tab; A top cap support member provided to support the rear of the top cap; and A welded portion for welding the electrode tab and the top cap; comprising, A top cap welding device for a cylindrical battery cell, characterized in that the above-mentioned pressurizing part pressurizes the battery case while controlling the angle between the electrode tab and the top cap or the distance between the electrode tab and the top cap so that the electrode tab corresponds to the position of the top cap.
In paragraph 1, The above-mentioned pressurizing unit is, Support frame; A pusher unit comprising a pusher member that presses the battery case, a centering member connected to one side of the pusher member, and a guide block provided on the lower side of the centering member and having a guide groove formed therein; A guide member provided to be partially inserted into the above guide groove to guide the guide block; and A top cap welding device for a cylindrical battery cell, characterized by including a first driving unit connected to one side of the above-mentioned pusher unit to drive the pusher unit forward or backward.
In paragraph 2, The above guide member includes a guide shaft and a second bearing member that surrounds the outer side of the guide shaft, and A top cap welding device for a cylindrical battery cell, characterized in that the guide groove comprises a clearance portion having a width greater than the outer diameter of the guide member and an alignment portion having a width corresponding to the outer diameter of the guide member.
In paragraph 3, When the guide member is located in the clearance portion, the pusher unit can rotate about the rotation axis located at one end of the pusher unit, but A top cap welding device for a cylindrical battery cell, characterized in that when the guide member is positioned in the alignment section, the pusher unit cannot rotate about the rotation axis.
In paragraph 3, A top cap welding device for a cylindrical battery cell, characterized in that the above gap portion is located closer to the pusher member than the above alignment portion.
In paragraph 2, A first groove is formed on the other surface of the pusher member that contacts the battery case so that a part of the battery case is inserted therein. A top cap welding device for a cylindrical battery cell, characterized in that the width of the first groove is provided to be smaller than the outer diameter of the battery case.
In paragraph 6, A top cap welding device for a cylindrical battery cell, characterized in that the portion connecting the other surface of the pusher member and the first groove is provided in a rounded shape.
In paragraph 2, The above transfer unit is, A transfer line for transferring the battery case in a direction perpendicular to the direction of movement of the pressurizing part; and A top cap welding device for a cylindrical battery cell, characterized by comprising: a mounting plate on which the battery case is mounted, and a mounting portion including a gripper member connected to the mounting plate and supporting a part of the battery case.
In paragraph 8, A top cap welding device for a cylindrical battery cell, characterized in that the above-mentioned mounting portion further includes a connecting portion connecting the mounting plate and the gripper member.
In paragraph 8, A top cap welding device for a cylindrical battery cell, characterized in that a second groove is formed on the other surface of the pusher member in contact with the battery case so that a part of the gripper member can be inserted.
In paragraph 2, A top cap welding device for a cylindrical battery cell, characterized in that a fourth groove is formed on one side of the support member in contact with the battery case, which is recessed toward the other side to allow the battery case to be seated thereon.
In paragraph 2, The above first driving unit is, A first support plate fixed to the above support frame; A first guide rail provided on the upper side of the first support plate and configured to guide the linear movement of the pusher unit; A first moving block configured to be engaged with the first guide rail and capable of reciprocating movement along a first linear movement section provided by the first guide rail; A second support plate connected to the first moving block above; A first contact member located on the side of the second support plate, with a cut formed at the lower edge that is open downwards; A first rotating block rotatably connected to the side of the support frame and configured to be in contact with a portion of the cut portion of the first contact member; and A top cap welding device for a cylindrical battery cell, characterized by including: a first rod member connected to one end of the first rotating block and configured to rotate the first rotating block by vertical driving.
In Paragraph 12, A top cap welding device for a cylindrical battery cell, characterized in that the above-mentioned pressurizing unit further includes an angle adjusting unit provided between the first driving unit and the pusher unit to adjust the pressurizing force and angle of the pusher unit.
In Paragraph 13, The above angle adjustment unit is, A second guide rail provided on the upper side of the first drive unit and configured to guide the linear movement of the pusher unit; A second moving block coupled to the second guide rail and configured to enable reciprocating movement along a second linear movement section provided by the second guide rail; A first fixing member fixed to the upper side of the first driving unit; A connecting block provided on the upper side of the second moving block, wherein one side is located on one side of the first fixed member and the other side is located on the other side of the first fixed member; A support shaft comprising a first support shaft and a second support shaft, each connected to both edges of the connecting block while penetrating the first fixing member; and A top cap welding device for a cylindrical battery cell characterized by including an elastic member comprising a first elastic member surrounding the outer side of the first support shaft and a second elastic member surrounding the outer side of the second support shaft.
A method for welding the top cap of a cylindrical battery cell using a top cap welding device for a cylindrical battery cell according to any one of claims 1 to 14, (S1) A step of transferring the battery case to one side or the other side through the transfer unit; (S2) A step of positioning the top cap at the rear of the electrode tab through the top cap holder; (S3) A step of supporting the rear of the top cap through the top cap support member; (S4) A step of pressing the battery case backward through the above-mentioned pressurizing part; and (S5) A step of welding the top cap and the electrode tab through the welded portion; characterized by a method for welding the top cap of a cylindrical battery cell.

Description

Top cap welding apparatus for a cylindrical battery cell and top cap welding method for a cylindrical battery cell using the same The present invention relates to a top cap welding device for a cylindrical battery cell and a top cap welding method for a cylindrical battery cell using the same. More specifically, it relates to a top cap welding device for a cylindrical battery cell capable of welding the electrode tab and the top cap of the cylindrical battery cell at a more accurate position, and a top cap welding method for a cylindrical battery cell using the same. With the increasing technological development and demand for mobile devices, rechargeable secondary batteries are being used as an energy source for various mobile devices. Secondary batteries are also attracting attention as an energy source for electric vehicles and hybrid electric vehicles, which are being presented as alternatives to conventional gasoline and diesel vehicles that use fossil fuels. Secondary batteries are classified according to the shape of the battery case into cylindrical and prismatic batteries, in which the electrode assembly is embedded in a cylindrical or prismatic metal can, and pouch-type batteries, in which the electrode assembly is embedded in a pouch-type case made of aluminum laminate sheets. Generally, cylindrical battery cells are used in which a jelly-roll type electrode assembly, wound with a separator sheet interposed between a positive electrode sheet and a negative electrode sheet, is housed in a cylindrical battery case. FIG. 1 is a cross-sectional view illustrating a cylindrical battery cell, and FIG. 2 is a drawing illustrating the appearance of an electrode tab of an electrode assembly welded to a top cap, viewed from the front and rear of the top cap. To manufacture a cylindrical battery cell, an electrode assembly is housed in an open cylindrical battery case, and a top cap is positioned at the top. A welding process is then performed to weld and connect the electrode tab of the electrode assembly to the top cap. In detail, the cylindrical battery cell (10) includes a battery case (11) with an open top, an electrode assembly (12) housed in the battery case (11), and a top cap (13) coupled to the top of the battery case (11). The top cap (13) is positioned on the upper part of the electrode assembly (12) and is electrically connected to the electrode tab (12a) of the electrode assembly (12), and is coupled to the upper open end of the battery case (11) to seal the electrode assembly (12) housed inside the battery case (11). The top cap (13) is electrically connected to the electrode tab (12a) through welding. The welding process is typically carried out with the battery case (11) containing the electrode assembly (12) being pressed toward the top cap (13) and the top cap (13) and the electrode tab (12a) in close contact. However, during the process of fixing the battery case (11) to bring the electrode tab (12a) and the top cap (13) into close contact, the position of the cylindrical battery case (11) may be misaligned, and a welding defect may occur in which the electrode tab (12a) and the top cap (13) are not welded at the designated position. Figure 1 is a cross-sectional view illustrating a cylindrical battery cell. Figure 2 is a drawing illustrating the appearance of the electrode tab of the electrode assembly welded to the top cap, viewed from the front and rear of the top cap. FIG. 3 is a perspective view of a top cap welding device for a cylindrical battery cell according to the present invention, viewed from one side. FIG. 4 is a perspective view of a top cap welding device for a cylindrical battery cell according to the present invention, viewed from the other side. FIG. 5 is a top cap welding device for a cylindrical battery cell according to the present invention, viewed from above. FIG. 6 is a perspective view illustrating a pressurizing part constituting a top cap welding device for a cylindrical battery cell according to the present invention. FIG. 7 is a perspective view illustrating a transfer unit constituting a top cap welding device for a cylindrical battery cell according to the present invention. FIG. 8 is a drawing for explaining a pusher unit constituting a top cap welding device for a cylindrical battery cell according to the present invention, in which the supplied battery case is offset to one side. FIG. 9 is a drawing for explaining a pusher unit constituting a top cap welding device for a cylindrical battery cell according to the present invention, in which the supplied battery case is offset to the other side. FIG. 10 is an exploded cross-sectional view of a rotating shaft constituting a top cap welding device for a cylindrical battery cell according to the present invention. FIG. 11 is a drawing for explaining the principle of rotation of a pusher unit by a guide member in a top cap welding device for a cylindrical battery cell according to the present invention, in whi