Electrode plate of electrolytic copper foil apparatus and manufacturing method thereof

Abstract

The present invention relates to an electrode plate of an electrolytic copper foil apparatus and a manufacturing method thereof, wherein the electrode plate, which is essential for a copper foil manufacturing process, is plated with low-cost lead (Pb) to reduce copper foil manufacturing costs. The present invention provides an electrode plate of an electrolytic copper foil apparatus for manufacturing copper foil, the electrolytic copper foil apparatus comprising: a pair of anode bases bent in a curved shape so as to be spaced apart from a lower portion of the outer circumferential surface of a drum roll; and a plurality of electrode plates attached to the inner surfaces of the pair of anode bases, wherein a lead (Pb) plating layer, in which Pb is plated to a certain thickness, is formed on the electrode plate.

Description

Electrode plate of an electrolytic copper foil device and method of manufacturing the same

[0001] The present invention relates to an electrode plate of an electrolytic copper foil device and a method for manufacturing the same, and more specifically, to an electrode plate of an electrolytic copper foil device and a method for manufacturing the same that is improved to reduce the manufacturing cost of copper foil by plating Pb (lead) onto an electrode plate that is essential in the copper foil manufacturing process.

[0002] Copper foil with a thickness of several µm to tens of µm, used in many electrical and chemical products such as secondary batteries, can be manufactured by an electrolysis (or electrolytic) method.

[0003] FIG. 1 illustrates a configuration diagram of an electrolytic copper foil apparatus for forming the copper foil by an electrolysis method. Referring to FIG. 1, the electrolytic copper foil apparatus (30) comprises a drum roll (31) which is a cathode electrode and an electrolytic cell (35) which rotatably supports the drum roll (31).

[0004] And the electrolytic cell (35) is equipped with a frame (36), a pair of anode bases (46, 51), a current bus (60), and an electrolyte supply nozzle (70). And the pair of anode bases (46, 51) are formed to be curved so as to be spaced apart from the lower outer surface of the drum roll (31).

[0005] Meanwhile, a plurality of thin electrode plates are attached to the inner surface of a pair of anode bases (46, 51) facing the outer surface of the drum roll (31). Additionally, a spaced gap is formed between the plurality of electrode plates and the outer surface of the drum roll (31).

[0006] And the current bus (60) is for supplying current to the anode base (46) and a plurality of electrode plates attached thereto.

[0007] In addition, the above electrolyte supply nozzle (70) supplies electrolyte into the electrolytic cell (35) and is positioned between the left and right anode bases (46, 51).

[0008] Meanwhile, the electrode plate (positive plate) that is essential in the manufacturing process of the copper foil (Cu Foil) of such secondary batteries is coated with iridium dioxide (IrO2). However, Ir (iridium) is a rare mineral and is about twice as expensive as Au (gold), a representative precious metal.

[0009] Accordingly, the aforementioned electrode plate previously accounted for a significant portion of the copper foil manufacturing cost.

[0010] In addition, in the conventional electrolytic copper foil production process, electrode plates require high durability and corrosion resistance.

[0011] Furthermore, while iridium-coated titanium electrode plates are currently the predominant type in general use, iridium is an expensive material that imposes a significant cost burden, and there were issues with limited durability under specific conditions.

[0012] Moreover, iridium (Ir) is an expensive and scarce metal with high price volatility in the international market and high supply and demand instability, and as of January 2025, it is trading at 270,000 won per gram.

[0013] The present invention was created to solve the aforementioned problems, and aims to provide a lead (Pb) coated electrode plate with excellent corrosion resistance that can be used stably for a long period in the electrolytic copper foil production process, and to provide an electrode plate for an electrolytic copper foil device and a method for manufacturing the same that can significantly reduce manufacturing costs compared to existing iridium-based electrode plates.

[0014] The present invention, for achieving the above-mentioned purpose, provides an electrode plate of an electrolytic copper foil device for manufacturing copper foil, comprising a pair of anode bases formed to be curved so as to be spaced apart from the lower outer surface of a drum roll, and a plurality of electrode plates attached to the inner surface of the pair of anode bases, wherein the electrode plates include a Pb plating layer formed by plating Pb (lead) to a predetermined thickness.

[0015] In a preferred embodiment of the present invention, the electrode plate of an electrolytic copper foil device is provided, characterized in that the Pb plating layer is formed with a thickness of 50 to 500 μm.

[0016] In a preferred embodiment of the present invention, the electrode plate of an electrolytic copper foil device is provided, characterized in that the electrode plate comprises a Sn plating layer formed by plating Sn to a predetermined thickness between the Pb plating layer and the electrode plate.

[0017] In a preferred embodiment of the present invention, the electrode plate of an electrolytic copper foil device is provided, characterized in that the Sn plating layer is formed with a thickness of 5 to 20 μm.

[0018] In a preferred embodiment of the present invention, the electrode plate of an electrolytic copper foil device is provided, characterized in that the electrode plate is made of a titanium (Ti) plate.

[0019] In a preferred embodiment of the present invention, a method for manufacturing electrode plates of an electrolytic copper foil apparatus for manufacturing copper foil comprising a pair of anode bases formed to be curved so as to be spaced apart from the lower outer surface of a drum roll, and a plurality of electrode plates attached to the inner surface of the pair of anode bases, the method comprises: (a) cutting a titanium plate to a predetermined size according to the specifications of the electrolytic copper foil apparatus and then manufacturing it to fit the shape of the anode bases; (b) removing an oxide layer and residual impurities present on the surface of the titanium plate and increasing the surface roughness; (c) removing the oxide layer and residual impurities using a sulfuric acid (H2SO4) solution to remove residues remaining on the surface of the titanium plate, and then washing with pure water; (d) immersing the titanium plate in an acidic electrolyte based on ionized tin salt (SnSO4) and supplying an electric current to electrodeposit tin to a predetermined thickness; (e) washing the plating solution and impurities remaining on the tin-plated titanium plate with distilled water and then drying. The present invention provides a method for manufacturing an electrode plate of an electrolytic copper foil device, characterized by including the step of (f) immersing the titanium plate on which Sn is electrodeposited in an ionized Pb-based acidic electrolyte and supplying an electric current to electrodeposit lead dioxide (PbO2) to a predetermined thickness.

[0020] In a preferred embodiment of the present invention, a method for manufacturing an electrode plate of an electrolytic copper foil device is provided, characterized in that in step (d), the Sn is electrodeposited to a thickness of 5 to 20 μm.

[0021] In a preferred embodiment of the present invention, a method for manufacturing an electrode plate of an electrolytic copper foil device is provided, characterized in that in step (e), the titanium plate is washed with a diluted sulfuric acid (H2SO4) solution.

[0022] In a preferred embodiment of the present invention, a method for manufacturing an electrode plate of an electrolytic copper foil device is provided, characterized in that in step (f), the lead dioxide (PbO2) is electrodeposited to a thickness of 50 to 500 μm.

[0023] In a preferred embodiment of the present invention, a method for manufacturing an electrode plate of an electrolytic copper foil device is provided, characterized by further including, after step (f), a step of washing and drying the plating solution and impurities with distilled water and then performing a peeling test using an adhesive tape.

[0024] According to an embodiment of the present invention, compared to the conventional Iro2 (iridium) coating currently widely used on the electrode plate (anode plate, Ti Plate) of an electrolytic copper foil device for producing electrolytic copper foil, the Pb (lead) coating has economic benefits and high conductivity, which allows for the maintenance of surface characteristics of the electrode plate evenly and makes it relatively easy to plate thinly and uniformly, thereby improving the efficiency of the electrolytic process.

[0025] Furthermore, under the same conditions, the performance and product quality of the Pb (lead) electrode plate are not inferior to those of the existing IrO2 (iridium) electrode plate.

[0026] Therefore, compared to conventional iridium-coated electrode plates, lead-coated electrode plates can significantly reduce manufacturing costs (expected to be more than 50%).

[0027] Furthermore, Pb (lead) electrode plates in the electrolytic process have superior electrical conductivity efficiency compared to conventional iridium-coated electrode plates, and the lifespan of the electrode plates is extended, reducing maintenance costs.

[0028] Figure 1 is a schematic diagram of an electrolytic copper foil device that forms a copper foil by an electrolysis method.

[0029] FIG. 2 is a diagram showing the configuration of a key part of an electrolytic copper foil device equipped with an electrode plate according to a first embodiment of the present invention.

[0030] FIG. 3 is a diagram showing the configuration of a key part of an electrolytic copper foil device equipped with an electrode plate according to a second embodiment of the present invention.

[0031] FIG. 4 is a cross-sectional view of an electrode plate of an electrolytic copper foil device according to a third embodiment of the present invention.

[0032] Figure 5 is a photograph showing the sequential experimental process of Pb (lead) DSA in liquid.

[0033] Figure 6 shows the change in composition of the sample in the Pb (lead) DSA liquid experiment.

[0034] Figure 7 is an SEM image of the PbO2 anode.

[0035] FIG. 8 is a flowchart of a method for manufacturing an electrode plate according to the present invention.

[0036] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0037] FIG. 2 shows a configuration diagram of the main parts of an electrolytic copper foil device equipped with an electrode plate according to the first embodiment of the present invention.

[0038] And FIG. 3 shows a configuration diagram of the main parts of an electrolytic copper foil device equipped with an electrode plate according to a second embodiment of the present invention.

[0039] In addition, FIG. 4 shows a detailed cross-sectional view of an electrode plate of an electrolytic copper foil device according to a third embodiment of the present invention.

[0040] Referring to FIGS. 2 to 4, the electrolytic copper foil apparatus comprises a drum roll which is a cathode as described with reference to FIG. 1, a pair of anode bases (110) formed to be curved so as to be spaced apart from the lower outer surface of the drum roll, and a plurality of electrode plates (120) attached to the inner surface of the anode bases (110, hereinafter referred to as anodes) to manufacture copper foil.

[0041] A Pb (lead) plating layer (130) is formed on such an electrode plate (120) in which Pb (lead) is plated to a predetermined thickness, and the Pb (lead) plating layer (130) is plated to a thickness of 50 to 500 μm. If the thickness of the Pb (lead) plating layer (130) is 50 μm or less, the plating layer may be damaged, and if the plating layer is damaged, current loss may occur, making it difficult to have characteristics according to the Pb plating layer. If the thickness of the Pb plating layer (130) is 500 μm or more, physical properties such as heat generation characteristics may be unstable, and there is a risk of cracks occurring. Therefore, it would be more preferable for the Pb plating layer (130) to be formed on the electrode plate (120) with a thickness of 50 μm or more.

[0042] And as shown in FIG. 4, a Sn (tin) plating layer (140) can be further formed on the surface of the electrode plate (120) below the Pb (lead) plating layer (130), with Sn (tin) plated to a predetermined thickness. Through this Sn (tin) plating layer (140), electrically stable characteristics can be achieved, such as by reducing the potential difference between the electrode plate (120) and the Pb (lead) plating layer (130) formed on it and compensating for the potential difference. Thus, the manufacturing of copper foil using the electrode plate manufactured in this way can be carried out stably.

[0043] This Sn (tin) plating layer (140) is plated with a thickness of 5 to 20 μm. If the Sn plating layer (140) is 5 μm or less, the Pb plating layer may not form well, and if it is 20 μm or more, a large amount of Sn is required for layer formation. Thus, it is preferable that the Sn plating layer (140) formed between the electrode plate (120) and the Pb plating layer (130) be formed with a thickness of 5 μm or more.

[0044] Also, the electrode plate (120) is made of a titanium plate (Titanium(Ti) Plate).

[0045] Next, a method for manufacturing an electrode plate of an electrolytic copper foil device according to the present invention will be described.

[0046] Referring again to FIGS. 2 to 4, first, a titanium plate is cut to a predetermined size according to the specifications of the electrolytic copper foil device, and then manufactured to fit the shape of the anode base (110) (titanium plate provision step S210).

[0047] Next, the oxide layer and residual impurities present on the surface of the titanium plate are removed, and the surface roughness is increased to arbitrarily improve the electrodeposition efficiency and adhesion of metal ions (electrodeposition efficiency improvement step S220).

[0048] Then, to remove residues remaining on the surface of the titanium plate, the oxide layer and residual impurities are removed using a sulfuric acid (H2SO4) solution, and then washed with pure water (washing step S230).

[0049] In addition, a titanium plate is immersed in an acidic (pH 4~6) electrolyte based on ionized tin salt (SnSO4), and an electric current is supplied to electrodeposit tin (Sn) to a thickness of 5~20㎛ (tin plating layer formation step S240).

[0050] This Sn (tin) plating layer (140) is plated with a thickness of 5 to 20 μm. If the Sn plating layer (140) is 5 μm or less, the Pb plating layer may not form well, and if it is 20 μm or more, a large amount of Sn is required for layer formation. Thus, it is preferable that the Sn plating layer (140) formed between the electrode plate (120) and the Pb plating layer (130) be formed with a thickness of 5 μm or more.

[0051] By means of such a Sn (tin) plating layer (140), the potential difference between the electrode plate (120) and the Pb (lead) plating layer (130) formed on it can be reduced to compensate for the potential difference, thereby enabling electrically stable characteristics. Thus, the manufacturing of copper foil using the electrode plate manufactured in this way can be carried out stably.

[0052] Next, the plating solution and impurities remaining on the tin-plated titanium plate are washed with distilled water and then dried (tin layer post-treatment step S250).

[0053] Then, a titanium plate electrodeposited with tin (Sn) is immersed in an ionized lead (Pb)-based acidic (pH 1~3) electrolyte, and lead dioxide (PbO2) is electrodeposited to a thickness of 50 to 500 μm by supplying an electric current (lead plating layer formation step S260).

[0054] A Pb (lead) plating layer (130) is formed through this electrodeposition process. If the thickness of the Pb (lead) plating layer (130) is 50 μm or less, the plating layer may be damaged, and if the plating layer is damaged, current loss may occur, making it difficult to have characteristics according to the Pb plating layer. If the thickness of the Pb plating layer (130) is 500 μm or more, physical properties such as heat generation characteristics may be unstable, and there is a risk of cracks occurring. Therefore, it would be more desirable for the Pb plating layer (130) to be formed on the electrode plate (120) with a thickness of 50 μm or more.

[0055]

[0056] Next, after washing and drying the plating solution and impurities with distilled water, a peeling test is performed using adhesive tape (washing and drying step S270).

[0057] Meanwhile, in the tin layer post-treatment step (S250), the titanium plate is washed with a diluted sulfuric acid (H2SO4) solution.

[0058] As described above, the electrode plate of the electrolytic copper foil device and the method for manufacturing the same according to the present invention are intended to replace the iridium (Ir) coating-based electrode plate (anode plate) that is essential in the copper foil manufacturing process generally used in secondary batteries.

[0059] That is, the electrode plate (120) is made of a titanium plate (Ti Plate), and instead of the conventional iridium coating method, lead (Pb) is plated on this titanium plate, so that the iridium electrode plate, which accounted for a large portion of the manufacturing cost of the copper foil, can be replaced with a lead-plated electrode plate (120).

[0060] Iridium is a rare mineral and is about twice as expensive as Au (gold), a representative precious metal, whereas the price of Pb (lead) is only at a considerably low level.

[0061] The electrode plate (120) of the electrolytic copper foil device according to the present invention can be applied to all electrode plates of equipment for producing electrolytic copper foil, electrode plates used for post-processing of electrolytic or rolled copper foil, plating of all metal surfaces used as bases for electrode plates such as titanium or Hastelloy for electrolytic copper foil, plating of surfaces for electrolytic copper foil made with electrode plate bases of 1 mm or more, or electrolytic cells and equipment for electrolytic copper foil using lead (Pb) plated electrode plates, and thus has significant added value.

[0062] In addition, the electrode plate of the electrolytic copper foil device and the method for manufacturing the same according to the present invention utilize lead (Pb) coating technology to improve the corrosion resistance and durability of the electrode plate, while simultaneously enabling cost reduction.

[0063] In addition, in the electrode plate of the electrolytic copper foil device and the method for manufacturing the same according to the present invention, high-purity Pb ​​(lead) and high-purity Sn (tin) are used as coating materials to plate a titanium plate, and can optionally be used in the form of an alloy with other metals.

[0064] In addition, in the electrode plate of the electrolytic copper foil device and the method for manufacturing the same according to the present invention, the plating (or coating) thickness is formed to a range of 50 μm or more in the case of Pb (lead), thereby simultaneously optimizing durability and conductivity.

[0065] In addition, to ensure stable lead (Pb) plating, tin (Sn) was plated onto a titanium plate to a thickness of 5 μm or more.

[0066] As such, the electrode plate of the electrolytic copper foil device and the method of manufacturing the same according to the present invention significantly reduced the manufacturing cost of the lead-coated electrode plate (120) compared to the existing iridium-coated electrode plate.

[0067] In addition, as shown in Table 1 below, the test results under the same conditions showed that the performance and product quality of the Pb (lead) electrode plate did not deteriorate compared to the IrO2 (iridium) electrode plate.

[0068] No. Classification Temperature (°C) Current Density (ASD) Voltage (V) Tensile Strength (MPa) Elongation (%) 1 Pb Electrode Plate 50 50 5.5 46 33.2 22 55 426 3.3 8 36 0 38 22.2 9 4 IrO₂ Electrode Plate 50 4.9 44 8 3.6 15 55 47 13.0 56 60 44 42.7

[0069] Furthermore, lead electrode plates are advantageous in the copper foil manufacturing process in terms of cost-effectiveness and durability.

[0070] As is well known, lead (Pb) is relatively inexpensive, has excellent processability, and provides outstanding corrosion resistance in specific environments. In particular, because of its strong resistance to sulfuric acid and sulfuric acid gas, it exhibits stable performance in processes using acidic electrolytes and effectively prevents corrosion by forming a protective oxide film (PbO).

[0071] These characteristics of lead (Pb) are the main reason for the development of Pb (lead) electrode plates in copper foil manufacturing processes that prioritize cost efficiency.

[0072] These Pb (lead) electrode plates are generally used in the zinc electro-refining process, and the electrode plates are used in the zinc electro-refining sulfuric acid-based electrolyte (H2SO4), and a lead oxide (PbO2) layer is formed on the lead electrode plates to effectively prevent corrosion of the acidic electrolyte and maintain stable electrochemistry.

[0073]

[0074] Pb (Lead) DSA (Dimensionally Stable Anode) in-liquid experiment

[0075] 1. Purpose of the experiment

[0076] After immersing a sample as shown in Fig. 5(a) in a copper sulfate solution at 60°C for 7 days, the change in the surface composition of the sample was measured.

[0077] At this time, the copper ion concentration is 87.39 g / L and the sulfuric acid concentration is 105.71 g / L.

[0078] 2. Experiment Procedure

[0079] First, the initial data of the sample is measured (Fig. 5(b)), and it is immersed in a copper sulfate solution and washed (Figs. 5(c) and (d)).

[0080] In addition, a copper sulfate solution is maintained at 60°C using a heat retention device and immersed for about a week (or 7 days), and then the coating components on the front and back sides of the sample are measured at a set time every day.

[0081] Then, five points on one side are measured using XRF (X-Ray Fluorescence), a non-destructive analysis method that analyzes the elements of a sample using X-ray fluorescence (e in Fig. 5).

[0082] Next, record and analyze the data for tin and lead.

[0083] Table 2 below is the experimental data above.

[0084] Ingredients\Time12 / 2315:3012 / 2415:3012 / 2515:3012 / 2615:3012 / 2715:3012 / 2815:3012 / 2915:3012 / 3015:30Pb97.06297.1197.37897.1997.04 / / 97.24Sn0.7080.7330.80.830.852 / / 0.877

[0085] In addition, Figure 6 shows photographs of changes in the surface of the sample taken in chronological order according to the above experiment. The test results confirmed that there was no visible detachment of the plating layer on the surface after immersion in the plating solution, and the results measured by XRF also showed that Pb and Sn were present within the measurement error range.

[0086] Figure 7 is an SEM image of a PbO2 anode according to temperature change.

[0087] As described above, the present invention has been explained with reference to an embodiment illustrated in the drawings, but this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent embodiments are possible therefrom.

[0088] Therefore, the true scope of protection of the present invention must be determined solely by the appended claims.

[0089] The present invention can be applied to various electrolytic copper foil manufacturing processes, such as copper foil for lithium-ion batteries, copper foil for electronic circuits, and copper foil for semiconductors and electronic components, and can be widely used throughout the copper foil production equipment and related device industries.

Claims

1. An electrolytic copper foil apparatus for manufacturing copper foil, comprising a pair of anode bases formed to be curved so as to be spaced apart from the lower outer surface of a drum roll, and a plurality of electrode plates attached to the inner surface of the pair of anode bases, The electrode plate of the electrolytic copper foil device is characterized by including a Pb plating layer formed by plating Pb (lead) to a predetermined thickness.

2. In Paragraph 1, The electrode plate of an electrolytic copper foil device, characterized in that the above Pb plating layer is formed with a thickness of 50 to 500 μm.

3. In Paragraph 1, The electrode plate of the electrolytic copper foil device is characterized by including a Sn plating layer formed by plating Sn to a predetermined thickness between the Pb plating layer and the electrode plate.

4. In Paragraph 3, The electrode plate of an electrolytic copper foil device, characterized in that the Sn plating layer is formed with a thickness of 5 to 20 μm.

5. In Paragraph 1, The electrode plate of an electrolytic copper foil device is characterized by the above electrode plate being made of a titanium (Ti) plate.

6. A method for manufacturing electrode plates of an electrolytic copper foil apparatus for manufacturing copper foil, comprising a pair of anode bases formed to be curved so as to be spaced apart from the lower outer surface of a drum roll, and a plurality of electrode plates attached to the inner surface of the pair of anode bases. (a) A step of cutting a titanium plate to a predetermined size according to the specifications of the electrolytic copper foil device, and then manufacturing it to fit the shape of the anode base; (b) a step of removing the oxide layer and residual impurities present on the surface of the titanium plate and increasing the surface roughness; (c) a step of removing the oxide layer and residual impurities using a sulfuric acid (H2SO4) solution to remove residues remaining on the surface of the titanium plate, and then washing with pure water; (d) a step of immersing the titanium plate in an acidic electrolyte based on ionized tin salt (SnSO4) and supplying an electric current to electrodeposit tin to a predetermined thickness; (e) washing the plating solution and impurities remaining on the tin-plated titanium plate with distilled water and drying it; and (f) A method for manufacturing an electrode plate of an electrolytic copper foil device, characterized by including the step of immersing the titanium plate on which Sn is electrodeposited in an ionized Pb-based acidic electrolyte and supplying an electric current to electrodeposit lead dioxide (PbO2) to a predetermined thickness.

7. In Paragraph 6, A method for manufacturing an electrode plate of an electrolytic copper foil device, characterized in that in step (d) above, the Sn is electrodeposited to a thickness of 5 to 20 μm.

8. In Paragraph 6, A method for manufacturing an electrode plate of an electrolytic copper foil device, characterized by washing the titanium plate with a diluted sulfuric acid (H2SO4) solution in step (e) above.

9. In Paragraph 6, A method for manufacturing an electrode plate of an electrolytic copper foil device, characterized in that, in step (f) above, the lead dioxide (PbO2) is electrodeposited to a thickness of 50 to 500 μm.

10. In Paragraph 6, A method for manufacturing an electrode plate of an electrolytic copper foil device, characterized by further including, after the above step (f), a step of washing and drying the plating solution and impurities with distilled water, and then conducting a peeling test using an adhesive tape.

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