KR-102962586-B1 - PROCESS FOR MANUFACTURING ELECTRODE ASSEMBLY

KR102962586B1KR 102962586 B1KR102962586 B1KR 102962586B1KR-102962586-B1

Abstract

The present invention provides a manufacturing process for an electrode assembly comprising the steps of: introducing a second separator (32), which has an extended length in the left-right direction, into a structure in which an anode (10), a first separator (31), and a cathode (20) are repeatedly stacked, to wrap the structure; simultaneously pressing the upper and lower parts of the structure including the introduced second separator (32) to strengthen the adhesion between the separator and the electrode; joining the left and right excess portions of the second separator (32) wrapping the structure vertically to adjust them to the specifications of the structure; and joining the joined second separator (32) horizontally to fix it. The manufacturing process for the electrode assembly enables wrapping to fit the size of the structure while minimizing the impact on the initial structure in which the anode, separator, and cathode are repeatedly stacked, thereby increasing the utility value of the electrode assembly.

Inventors

정재봉
안창범
서상진
심동국
장영철

Assignees

주식회사 엘지에너지솔루션

Dates

Publication Date: 20260507
Application Date: 20210622

Claims (13)

(1) A step of wrapping a structure in which a positive electrode, a first separator, and a negative electrode are repeatedly stacked, by introducing a second separator with a length extended in the left-right direction; (2) A step of simultaneously applying pressure to the upper and lower ends of a structure including the introduced second separator to strengthen the adhesion between the separator and the electrode; (3) A step of joining the left and right excess portions of the second separator covering the structure vertically to adjust them to the specifications of the structure; and (4) Includes the step of joining and fixing the joined second separator membranes left and right, and In the above (1) step, the second separator, which has a length extended in the left-right direction, is introduced at one or more of the top and bottom of the structure, and The length of the second separator is 1.5 to 2.5 times longer than the perimeter length of the laminated structure to be wrapped, and A process for manufacturing an electrode assembly in which, when wrapping a structure with a second separator introduced in step (1) above, the second separator is adsorbed at one or more of the left and right directions of the structure to secure an extra space on the side of the structure.
In claim 1, A manufacturing process for an electrode assembly characterized in that the first separator constituting the above structure folds the portions protruding left and right from the anode and cathode to come into contact with one of the adjacent separators.
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In claim 1, A manufacturing process for an electrode assembly characterized by the fact that when wrapping a structure with a second separator introduced in step (1) above, the left and right ends of the second separator are positioned to be in contact with the top or bottom of the structure.
In claim 5, A manufacturing process for an electrode assembly characterized by, when the upper and lower ends of the structure are pressed in step (2) above, the parts where the left and right ends of the second separator come into contact with the upper or lower end of the structure are joined to the upper or lower end of the structure using a roller in an outward direction from the center of the structure.
In claim 6, A manufacturing process for an electrode assembly characterized by, when a roller contacts the left and right ends of the second separator and is fixed to the top or bottom of the structure so as not to fold the second separator, adsorbing the second separator in the left and right directions of the structure to hold the second separator flat in the area where the roller passes.
In claim 1, A manufacturing process for an electrode assembly characterized by using a primary pressurizing member that moves up and down at a position separated from the positive and negative electrodes so that the first separator protruding to the left and right is not folded when joining the second separator in step (3) above.
In claim 8, A manufacturing process for an electrode assembly, characterized in that the side of the first pressurizing member is formed obliquely so that the pressurizing member and the second separator can come into contact over a wider range when the pressurizing member moves in the direction of joining the second separator.
In claim 1, A manufacturing process for an electrode assembly characterized by, when joining the second separator in step (3) above, if the position where the left and right ends of the second separator meet is positioned on the left or right side of the structure, the second separator is joined vertically based on the position where the left and right ends of the second separator meet, and the opposite side is joined vertically at a position horizontal to the above position.
In claim 6, A manufacturing process for an electrode assembly characterized in that, in step (2) above, the left and right ends of the second separator are joined to the top or bottom of the structure, and in step (3) above, the left and right excess portions of the second separator are joined vertically at a horizontal position to the top or bottom of the structure to which the second separator is joined.
In claim 1, A manufacturing process for an electrode assembly characterized by, when joining the second separator in step (4) above, folding the separator vertically so that the second separator joined in step (3) above comes into contact with the second separator covering the side of the structure, and then joining the separator using a secondary pressure member that moves left and right.
An electrode assembly manufactured according to the electrode assembly manufacturing process of claim 1.

Description

Electrode Assembly Manufacturing Process The present invention relates to a process for manufacturing an electrode assembly. Unlike primary batteries, secondary batteries are rechargeable and are currently the subject of extensive research and development due to their potential for miniaturization and high capacity. As technological development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rising rapidly. A secondary battery is constructed by embedding an electrode assembly within a battery case (pouch, can, etc.). The electrode assembly mounted inside the battery case consists of a stacked structure of a positive electrode, separator, and negative electrode, enabling repeated charging and discharging. Conventionally, electrode assemblies were manufactured using a lamination and stacking process. Specifically, multiple monocells, each composed of a stacked anode, separator, cathode, and separator, are stacked, and the stacked structure is secured with tape. In the lamination and stacking method, the anode, separator, cathode, and separator are continuously unwound and supplied while wound in a roll form. The anode and cathode are cut to a specific size from the separator and moved, passing through a laminating device. At this time, the anode and cathode have positive active material and negative active material coated on both sides of the positive current collector and negative current collector, respectively. While passing through the laminating device, adhesion occurs between the anode, separator, and cathode through heat and pressure. In this bonded state, the gaps between adjacent anodes (or adjacent cathodes) are cut, and a single monocell is continuously manufactured by stacking the anode, separator, cathode, and separator in that order from top to bottom. The above monocells are manufactured into an electrode assembly by stacking a predetermined number of them; upon completion of stacking, each end of a tape is adhered to the top and bottom monocells, respectively, to ensure fixation. However, this method of fixing monocells using tape causes the ends of the tape to protrude additionally from the top and bottom layers, resulting in a difference in thickness. Furthermore, when the tape is attached, a problem may arise where a portion of the edge of the cathode (which is cut relatively larger than the anode for stability) folds. As such, the difference in thickness and the folding of the cathode increase internal resistance and potentially accelerate electrode degradation. Accordingly, the inventors of the present invention have completed the present invention by researching an electrode assembly manufacturing process capable of solving the aforementioned problem. FIGS. 1A and 1B are drawings illustrating exemplary laminated structures applied to the manufacturing process of an electrode assembly of the present disclosure. Compared to the laminated structure of FIG. 1A, the laminated structure of FIG. 1B has a structure in which separator portions protruding left and right from the anode and cathode are folded and come into contact with one of the adjacent separators. FIGS. 2a and 2b are drawings showing an exemplary electrode assembly manufactured according to the electrode assembly manufacturing process of the present disclosure. FIGS. 3A, 3B, 3C, 3D, and 3E are drawings illustrating, in sequence, an exemplary electrode assembly manufacturing process of the present disclosure using the laminated structure of FIG. 1A. FIGS. 4a, 4b, 4c, and 4d are drawings illustrating, in sequence, an exemplary electrode assembly manufacturing process of the present disclosure using the laminated structure of FIG. 1b. Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of this disclosure, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of this disclosure and do not represent all of the technical spirit of this disclosure; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application. In the drawings, the size of each component or specific part constituting the component is exaggerated, omitted, or schematically depicted for convenience and clarity of explanation. Accordingly, the size of each component does not entirely reflect its actual size. Where it is determined that a specific description of related known functions or configurations could unnecessarily obscure the essence of the present disclosure, such description shall be omitted. The present disclosure relates to a manufacturi