EP4610406A1

EP4610406A1 - Positive electrode assembly for manufacturing copper foil

Info

Publication number: EP4610406A1
Application number: EP24179929.5A
Authority: EP
Inventors: Sang Wook Kim; Sang Soo Kim; Mi Jung Park; Jong Yeob Kim
Original assignee: Wesco Electrode Co Ltd
Current assignee: Wesco Electrode Co Ltd
Priority date: 2024-02-27
Filing date: 2024-06-04
Publication date: 2025-09-03
Also published as: KR20250131514A

Abstract

Disclosed is a positive electrode assembly for manufacturing copper foil. The positive electrode assembly includes a positive electrode having a concave, partially cylindrical shape corresponding to a drum-shaped negative electrode and a base configured to support the positive electrode. The positive electrode includes a plurality of quadrangular positive electrode segments disposed in each of a circumferential direction and an axial direction. Edges of each of the positive electrode segments are not adjacent to edges of positive electrode segments disposed thereabove and therebelow so as to be adjacent thereto, and each of a plurality of fastening bolts configured to fix the positive electrode segments to the base is spaced apart from fastening bolts disposed thereabove and therebelow by a predetermined distance in the axial direction.

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a positive electrode of an apparatus for manufacturing electrolytic copper foil, and more particularly to a positive electrode assembly for manufacturing copper foil capable of improving productivity through the use of high current, thereby producing copper foil having a more uniform thickness.

Description of the Related Art

Korean Patent Application Publication No. 10-2019-0038325 discloses manufacture of copper foil using electrolytic reaction. The technical details of the above patent application publication may be said to be known in the art to which the present invention pertains. Briefly, as shown in FIG. 1, an electroplating apparatus including an insoluble positive electrode assembly 20 immersed in an electrolytic solution 12 of an electrolytic bath 10 and a rotary drum-shaped negative electrode assembly 30 is used to manufacture electrolytic copper foil.
The insoluble positive electrode assembly 20 is installed so as to face the drum-shaped negative electrode assembly 30 and has a partially cylindrical shape with a concave shape so as to correspond to a circular circumference of the drum-shaped negative electrode assembly 30. When energization occurs between the insoluble positive electrode assembly 20 and the drum-shaped negative electrode assembly 30, a metal component may be grown on the surface of the drum-shaped negative electrode assembly 30.
Specifically, when the drum-shaped negative electrode assembly 30 is rotated relative to the positive electrode assembly 20 for plating in an energized state, copper foil is formed on the drum-shaped negative electrode assembly 30 based on electrolytic precipitation. The copper foil thus formed may be peeled off the drum-type negative electrode assembly 30, whereby the copper foil may be continuously obtained. A front surface of the positive electrode assembly 20 corresponding to the negative electrode assembly 30 may be said to be a part for causing substantive electrolytic reaction.
The positive electrode assembly 20 generally includes a positive electrode 22 installed so as to correspond to the negative electrode assembly 30 and a base 24 configured to support the positive electrode 22. In general, a fastening element, such as bolts, is used to couple the positive electrode 22 to the base 24 in order to fix the positive electrode 22. If the positive electrode assembly 20 is made of a single continuous plate, this is most desirable in terms of uniformity of current density, and therefore the quality of copper foil produced is guaranteed. In practice, however, the positive electrode 22 is constituted by a plurality of segments, each of which is fixedly mounted to the base 24.
In addition, as described above, the positive electrode 22 must be spaced apart from the drum-shaped negative electrode by an equal distance. When the positive electrode 22 is fixed to the titanium base 24, therefore, the flat positive electrode is coupled to the concave base 24 in tight contact therewith using a plurality of bolts. That is, the flat positive electrode segments are mounted to the base 24 in tight contact therewith by fastening force of the bolts in the state in which each of the flat positive electrode segments is deformed so as to have a concave shape.
In order to deform the flat positive electrode using the fastening force of the bolts such that the flat positive electrode has a partially arc section, however, the fastening force of the bolts must be considerably high such that the positive electrode can be deformed. As a result, it may be difficult to achieve good results due to physical deformation of the positive electrode and the presence of residual stress in the positive electrode.
In addition, the thickness of the positive electrode is substantially limited in order to achieve such deformation. For example, each currently used positive electrode has a thickness of about 1 mm. However, this thickness is undesirable in terms of achieving improvement of efficiency based on high current, which has been widely adopted in recent years. The present invention provides an efficient proposal in terms of use of high current in the positive electrode.
Positive electrodes 22, which are currently in common use, are disposed as one in a transverse direction (an axial direction of a cylindrical negative electrode) and as a plurality in a longitudinal direction (a circumferential direction of the negative electrode). When copper foil is formed using the plurality of positive electrodes 22, overall uniform copper foil is not formed with respect to one positive electrode 22, and the thickness of copper foil formed at the part corresponding to the entire border of the positive electrode 22 and the thickness of copper foil formed at the negative electrode corresponding to a middle part of the positive electrode 22 are different from each other, resulting in stains on the entirety of the copper foil, whereby there are some problems in terms of uniformity.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an electrolytic positive electrode capable of achieving efficient production based on high current.
It is another object of the present invention to provide an electrolytic positive electrode configured to produce copper foil with uniform quality.
It is a further object of the present invention to provide an electrolytic positive electrode capable of producing a high-quality product while improving productivity by using a smaller number of bolts.
In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a positive electrode assembly for manufacturing copper foil, the positive electrode assembly including a positive electrode having a concave, partially cylindrical shape corresponding to a drum-shaped negative electrode and a base configured to support the positive electrode. The positive electrode includes a plurality of quadrangular positive electrode segments disposed in each of a circumferential direction and an axial direction. Edges of each of the positive electrode segments are not adjacent to edges of positive electrode segments disposed thereabove and therebelow so as to be adjacent thereto. Each of a plurality of fastening bolts configured to fix the positive electrode segments to the base is spaced apart from fastening bolts disposed thereabove and therebelow by a predetermined distance in the axial direction.
The fastening bolts may fix the positive electrode segments to the base in the state in which a flat shape of each of the positive electrode segments is maintained such that the positive electrode segments are not deformed.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a view illustrating a conventional electrolytic copper foil manufacturing apparatus; and
FIG. 2 is a view illustrating a positive electrode assembly according to the present invention in an unfolded state.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings.
FIG. 2 shows a positive electrode assembly according to the present invention in an unfolded state. As shown, a plurality of positive electrode segments S is disposed in an axial direction X and a circumferential direction R. In a conventional layout structure, a single segment is disposed in the axial direction, whereby there is a difference in thickness between a border part of copper foil produced, including an edge, and a middle part of the copper foil, as described above.
In the following description, the axial direction X and the circumferential direction R are based on the cylindrical negative electrode. In FIG. 2, in which the positive electrode assembly is shown in an unfolded state, the axial direction X may be referred to as a leftward-rightward direction, and the circumferential direction R may be referred to as an upward-downward direction.
In the present invention, a plurality of segments S is disposed in each of the axial direction X and the circumferential direction R, whereby the size of each segment S is substantially greatly reduced. Since the distance between the edge and the middle part of each segment S is very small, the thickness difference of copper foil produced may be minimized. Here, minimizing the thickness difference of the copper foil means that it is possible to produce substantially uniform copper foil.
The segments S are disposed in the circumferential direction R so as to be spaced apart from each other in the axial direction X such that the left and right edges of the segments do not coincide with each other. This serves to prevent four edges of the segments each having substantially a quadrangular shape from being concentrated on each other. When describing the disposition of the segments S of the present invention with respect to the edges, the disposition of the segments S is designed to ensure that the segments are uniformly distributed over the entirety of the positive electrode while avoiding concentration of the edges of segments adjacent to each other above and below.
Next, the plurality of segments constituting the positive electrode of the present invention and a configuration to fix the segments to a base will be described. The plurality of segments having the above disposition may be mounted to the concave base using a plurality of bolts or the like, wherein the segments may be deformed by fastening force of the bolts, as previously described.
In order for the segments to be deformed by the fastening force so as to correspond to the concave shape of the base, i.e., to be concave in the circumferential direction, the fastening force must be very high or the thickness of each segment must be small. The current trend is to increase productivity of copper foil by increasing the magnitude of current. That is, it is necessary to use thick positive electrode segments in order to use high current.
In the present invention, therefore, the thickness (e.g., 1.5 to 7 mm) of each positive electrode segment S is greater than the thickness (about 1 mm) of a conventional positive electrode segment. When thick positive electrode segments S are used, as described above, high current may be used, whereby productivity of electrolytic copper foil may be greatly improved, as described above, which is obvious to those skilled in the art. That is, the present invention provides a positive electrode assembly capable of responding to the recent trend of using high current to improve productivity.
In the present invention, the plurality of positive electrode segments S is fixed to the base 2 in the state in which a flat shape of each of the positive electrode segments is maintained. That the plurality of positive electrode segments S is mounted to the base in the state in which the flat shape of each of the positive electrode segments is maintained means that it is possible to use positive electrode segments S that are thicker than conventional positive electrode segments, whereby it is possible to use high current.
When such thick positive electrode segments S are used, each of the positive electrode segments S may have a very small length in the circumferential direction such that the plurality of positive electrode segments can be disposed as a shape closer to a circular shape so as to correspond to a drum-shaped negative electrode. That is, a larger number of positive electrode segments may be used in the circumferential direction R such that the positive electrode segments have a shape close to an arc shape so as to overall correspond to the negative electrode, compared to the positive electrode segments being deformed so as to correspond to the concave arc shape of the base by fastening force in the prior art.
That shape deformation by the fastening force does not occur may mean that it is possible to fix the positive electrode segments S using substantially the minimum fastening force of the fastening bolts B. In addition, that the minimum fastening force is required may mean that it is possible to minimize the number of fastening bolts B.
For example, in terms of the number of positive electrode segments, about 16 conventional positive electrode segments are used in the circumferential direction R, whereas about 55 positive electrode segments S of the present invention are used, which means that the length of each positive electrode segment S in the circumferential direction is significantly small. When a large number of positive electrode segments is disposed in the circumferential direction R, as described above, it is possible to provide a positive electrode having a shape closer to an arc shape so as to correspond to the cylindrical negative electrode.
As shown in FIG. 2, the fastening bolts B are disposed so as not to overlap each other in a vertical direction (circumferential direction), which is equivalent to disposition of the segments such that the corners thereof are not concentrated. That is, the plurality of fastening bolts B is spaced apart from each other by a predetermined distance in the axial direction X with respect to segments S adjacent to each other above and below. Such disposition of the fastening bolts B is intended to maximally inhibit any possible degradation in quality of a product.
As described above, the flat shape of each of the positive electrode segments S of the present invention is maintained without deformation in sectional shape by the fastening bolts 6. At the same time, the number of positive electrode segments S is sufficiently increased in order to ensure that the side or sectional shape of the plurality of positive electrode segments is as close to an arc as possible.
According to the present invention, as described above, when the positive electrode segments S are fastened to the base 2 by the plurality of fastening bolts B, the positive electrode segments are assembled while the flat shape of each of the positive electrode segments is maintained without deformation due to the fastening force. As a result, it is possible to increase the thickness of each of the positive electrode segment S, whereby it is possible to supply high current, and therefore it is possible to achieve high efficiency.
In the present invention, it was confirmed by experiment that highest efficiency is achieved when the thickness of each of the positive electrode segments S necessary to use high current is within a range of 1.5 mm to 7 mm and that the efficiency decreases when the thickness of each of the positive electrode segments exceeds the above range. It was also confirmed that the thickness of each of the positive electrode segment S is preferably 2 to 5 mm.
As is apparent from the above description, in the present invention, a plurality of positive electrode segments is disposed in each of an axial direction and a circumferential direction. Since the plurality of positive electrode segments constitutes a positive electrode, it is possible to prevent thickness nonuniformity due to concentration of edges, whereby it is possible to produce copper foil having an overall uniform thickness.
In addition, since the positive electrode segments are assembled in the state in which a flat shape of each of the positive electrode segments is maintained such that the positive electrode segments are not deformed, it is possible to minimize limitations on the thickness of each of the positive electrode segments. That is, it is possible to use thicker positive electrode segments by applying the structure of the present invention. When such thicker positive electrode segments are used, it is possible to substantially improve productivity through the use of high current.
In addition, according to the present invention, it is possible to fix the positive electrode segments to a base using fastening force of bolts that does not cause deformation of the positive electrode segments. Therefore, it is possible to easily assemble the positive electrode segments in a production process, whereby it is possible to substantially improve productivity.
Furthermore, it is possible to significantly reduce the number of fastening bolts necessary to fix the positive electrode segments to the base. This is not only advantageous in an assembly process but also means that the quality of a product can be improved due to the reduced number of fastening bolts. In addition, it is possible to easily replace partially damaged segments with new ones and to regenerate the damaged segments by recoating the damaged segments.
Those skilled in the art to which the present invention pertains will appreciate that various modifications are possible within the scope of the basic technical ideas of the present invention as described above. In addition, it is a matter of course in the spirit of the provisions of the Patent Act that the scope of protection of the present invention should be construed on the basis of the description in the claims.

Claims

A positive electrode assembly for manufacturing copper foil, comprising, a positive electrode having a concave, partially cylindrical shape corresponding to a drum-shaped negative electrode, and a base configured to support the positive electrode, characterized in that;
the positive electrode comprises a plurality of quadrangular positive electrode segments (S) disposed in each of a circumferential direction (R) and an axial direction (X),

edges of each of the positive electrode segments are not adjacent to edges of positive electrode segments disposed thereabove and therebelow so as to be adjacent thereto, and

a fastening bolt configured to fix each of the plurality of positive electrode segments disposed in the circumferential direction to the base is spaced apart, by a predetermined distance in the axial direction (X), from a fastening bolt of a positive electrode segment adjacent thereto in the circumferential direction (R).
The positive electrode assembly according to claim 1, characterized in that the fastening bolts fix the positive electrode segments to the base in a state in which a flat shape of each of the positive electrode segments is maintained such that the positive electrode segments are not deformed.