METHOD FOR MANUFACTURING ELECTRODE FOR RECHARGEABLE BATTERY

Abstract

A method for manufacturing an electrode for a rechargeable battery includes, with reference to a center axis that divides a metal sheet left and right, setting a first coating line that is parallel with the center axis at a location deflected to one side, and a second coating line that is parallel with the center axis at a location deflected to the other side so as to correspond to the first coating line with reference to the virtual center axis and coating an electrode slurry on the metal sheet while alternately moving a slot die to the first coating line and the second coating line.

Claims

1. A method for manufacturing an electrode for a rechargeable battery, comprising: with reference to a center axis that divides a metal sheet left and right, setting a first coating line that is parallel with the center axis at a location to the left of the center axis, and a second coating line that is parallel with the center axis at a location to the right of the center axis so as to correspond to the first coating line with reference to the center axis; and coating an electrode slurry on the metal sheet while laterally moving a slot die between the first coating line and the second coating line.

2. The method for manufacturing the electrode for the rechargeable battery of claim 1, wherein the first coating line is set at a location that is separated from a left edge of the metal sheet by a distance that is more than 10% to less than 50% of a width of the metal sheet, and the second coating line is set at a location that is separated from a right edge of the metal sheet by a distance that is more than 10% to less than 50% with respect to the width of the metal sheet.

3. The method for manufacturing the electrode for the rechargeable battery of claim 1, wherein the coating of the electrode slurry on the metal sheet comprises: producing a first state in which a left edge of the slot die is located on the first coating line and the electrode slurry is coated along the first coating line; and producing a second state in which a right edge of the slot die is located on the second coating line and the electrode slurry is coated along the second coating line, and in the first state and the second state, the edge of the slot die that is not located on either of the first coating line and the second coating line is located on one of a third coating line that is parallel with the first coating line and the second coating line, and are respectively set at opposite ends of the metal sheet.

4. The method for manufacturing the electrode for the rechargeable battery of claim 3, wherein the slot die is set to alternate between the first state and the second state, a first electrode line is formed between the first coating line and the second coating line in both of the first state and the second state, a second electrode line is formed between the second coating line and the third coating line that is adjacent to the second coating line in the first state, and a third electrode line is formed between the first coating line and the third coating line that is adjacent to the first coating line in the second state.

5. The method for manufacturing the electrode for the rechargeable battery of claim 4, wherein a first uncoated portion, which is an uncoated region having the first coating line as a boundary is set in the third electrode line in the first state, and a second uncoated portion, which is an uncoated region having the second coating line as a boundary is set in the second electrode line in the second state.

6. The method for manufacturing the electrode for the rechargeable battery of claim 5, further comprising forming an irregular-shaped electrode by notching the metal sheet with: a first shape that includes at least a part of the third electrode line, excluding the first uncoated portion, and at least a part of the first electrode line; and a second shape that includes at least a part of the second electrode line, excluding the second uncoated portion, and at least a part of the first electrode line, wherein notching with respect to the first shape and notching with respect to the second shape are respectively carried out with reference to a virtual line that equally divides the first electrode line between boundaries of the first electrode line.

7. The method for manufacturing the electrode for the rechargeable battery of claim 6, wherein each of the first shape and the second shape comprises: a first electrode portion derived from the first electrode line; and a second electrode portion derived from the second electrode line or the third electrode line, and extended from the first electrode portion and having a size that is smaller than the first electrode portion such that at least one step difference is formed on a plane, and the metal sheet is notched into the first shape and the second shape with different electrodes that form the first shape and the second shape.

8. The method for manufacturing the electrode for the rechargeable battery of claim 7, wherein the step difference comprises a step difference corner that is formed in a portion where an exterior side of the first electrode portion and an exterior side of the second electrode portion cross each other at an angle of more than 30 degrees and less than 180 degrees, and in the step difference corner, the metal sheet is additionally notched such that a part of each of the first electrode portion and the second electrode portion are inwardly recessed such that an exterior circumference recess portion is formed.

9. The method for manufacturing the electrode for the rechargeable battery of claim 8, wherein the exterior circumference recess portion comprises, on a plane: a rounded structure including a curved line; a complex structure in which a curved line and a straight line are connected; or a polygonal structure in which a plurality of straight lines are connected.

10. The method for manufacturing the electrode for the rechargeable battery of claim 8, wherein the step difference comprises one or more of the step difference corners.

11. The method for manufacturing the electrode for the rechargeable battery of claim 10, wherein the step difference comprises only one step difference corner.

12. The method for manufacturing the electrode for the rechargeable battery of claim 7, wherein notching is additionally carried out to form an electrode tab that externally protrudes from at least one of the first electrode portion and the second electrode portion.

13. The method for manufacturing the electrode for the rechargeable battery of claim 7, wherein notching is additionally carried to chamfer the corners of at least one of the first electrode portion and the second electrode portion.

14. The method for manufacturing the electrode for the rechargeable battery of claim 6, further comprising rolling and drying the first electrode line, the second electrode line, and the third electrode line.

Description

DESCRIPTION OF THE DRAWINGS

[0070] FIG. 1 is a schematic view of an electrode manufacturing method according to a conventional method.

[0071] FIG. 2 is a plan schematic view of an electrode sheet coated with an electrode slurry according to a prior art.

[0072] FIG. 3 is a schematic view of an irregular-shaped battery cell according to a prior art.

[0073] FIG. 4 is a flowchart of a manufacturing method according to one exemplary embodiment of the present invention.

[0074] FIG. 5 and FIG. 6 are schematic views of a process for coating an electrode slurry on a metal sheet according to the exemplary embodiment of the present invention.

[0075] FIG. 7 is a schematic view of a process for notching the metal sheet coated with the electrode slurry into an irregular shape according to the exemplary embodiment of the present invention.

[0076] FIG. 8 is a schematic plan view of an irregular-shaped electrode for a rechargeable battery according to the exemplary embodiment of the present invention.

MODE FOR INVENTION

[0077] Hereinafter, the exemplary embodiments of the present invention will be described in detail, referring to the accompanying drawings. However, in the description of the present disclosure, descriptions for already known functions or components will be omitted for clarifying the present disclosure.

[0078] In order to clearly describe the present disclosure, parts which are not related to the description are omitted, and the same reference numerals refer to the same or like components, throughout the specification. In addition, since the size and the thickness of each component shown in the drawing are arbitrarily represented for convenience of the description, the present disclosure is not limited to the illustration.

[0079] FIG. 4 is a flowchart of a method for manufacturing an electrode for a rechargeable battery according to an exemplary embodiment of the present invention, FIG. 5 and FIG. 6 are schematic views of a process for coating an electrode slurry on a metal sheet, and FIG. 7 is a schematic view of a process for notching the metal sheet.

[0080] Referring to the drawings, a manufacturing method according to the present invention may include a process 1 for setting coating lines on a metal sheet, a process 2 for coating an electrode slurry while moving a slot die to be alternately located on predetermined coating lines, and a process 3 for notching the metal sheet together with the electrode lines into a predetermined shape.

[0081] First, in the process 1, with reference to a virtual center axis A-A that divides a metal sheet 200 to the left and right, a first coating line CL1 that is parallel with the central axis may be set at a location deflected to one side.

[0082] In addition, with reference to the virtual center axis A-A, a second coating line CL2 that is parallel with the center axis A-A at a location that is deflected to the other side may be set corresponding to the first coating line CL1.

[0083] Next, the process 2 is carried out. In the process 2, the electrode slurry is coated on the metal sheet 200 while moving a slot die 250 in which the electrode slurry is loaded to be alternately located at the first coating line CL1 and the second coating line CL2.

[0084] The process 2 is a step that includes producing a first state of FIG. 5 and a second state of FIG. 6, and during which the first state and the second state are alternately produced.

[0085] Here, as shown in FIG. 5, the first state implies a state in which one side of the slot die 250 is located in the first coating line CL1, and the electrode slurry is coated along the first coating line CL1.

[0086] The second state implies a state in which the other end of the slot die 250 is located in the second coating line CL2, and the electrode slurry is coated along the second coating line CL2.

[0087] A side end of the slot die 250, which is not located in either of the first coating line CL1 or the second coating line CL2 in the first state and the second state is located between third coating lines CL3 and CL3 that are parallel with the first coating line CL1 and the second coating line CL2.

[0088] That is, the third coating lines CL3 add CL3 are coating lines that are additionally set at opposite ends of the metal sheet 200. Depending on cases, the third coating lines CL3 and CL3 may be set while simply moving the slot die 250 in the process 1.

[0089] However, the slot die 250 discharges the electrode slurry between the first coating line CL1 and the second coating line CL2 in any state, and accordingly, a first electrode line 210 can be formed between the first coating line CL1 and the second coating line CL2 in the first state and the second state.

[0090] In the first state, one end of the slot die 250 is deflected over the second coating line CL2 such that a second electrode line 220 may be formed between the second coating line CL2 and the third coating line CL3 that is adjacent to the second coating line CL2. Simultaneously, a first uncoated portion 201, which is an coated region while having the first coating line CL1 as a boundary may be set in a third electrode line 230, which will be described later.

[0091] On the contrary, when the other end of the slot die 250 is deflected over the first coating line CL1, the third electrode line 230 may be formed between the first coating line CL1 and the third coating line CL3 that is adjacent to the first coating line CL1. Simultaneously, a second uncoated portion 202, which is an uncoated region while having the second coating line CL2 as a boundary, may be set in a second electrode line 220, which will be described later.

[0092] After such a coating process, rolling and drying the first electrode line 210, the second electrode line 220, and the third electrode line 230 may be carried out.

[0093] Next, the process 3 is carried out. In the process 3, the metal sheet 200 is notched with a first shape X that includes at least part of the third electrode line 230, excluding the first uncoated portion 201 and a part of the first electrode line 210, and a second shape X that includes at least a part of the second electrode line 220, excluding the second uncoated portion 202 and a part of the first electrode line 210, which does not overlap the first shape X such that an irregular-shaped electrode can be formed.

[0094] In this case, the first shape X and the second shape X1 may be respectively notched with reference to the virtual line A-A that equally divides the first electrode line 210 between the boundaries of the first electrode line 210.

[0095] In FIG. 7, when the notching is carried out, one stepped corner is included, but one or more stepped corners may be included depending on a range of the notching, and accordingly, an irregular-shaped electrode having various polygonal structures may be manufactured.

[0096] In addition, in the process 3, notching for forming an electrode tab 270 that protrudes to the outside from a second electrode portion 262 may be additionally carried out. However, depending on a desired shaped of the irregular-shaped electrode, notching that forms an electrode tab 270 that protrudes to the outside from a first electrode portion 261 may be carried out.

[0097] FIG. 8 is a schematic view of an irregular-shaped electrode according to an exemplary embodiment of the present invention, and an irregular-shaped electrode notched in the process 3 will be described in detail with reference to FIG. 8, together with FIG. 7.

[0098] Referring to the drawings, the first shape X and the second shape X respectively have an irregular-shaped polygonal structure on a plane, each including one step difference corner.

[0099] Specifically, the first shape X and the second shape X may respectively include a first electrode portion 261 derived from the first electrode line 210, and a second electrode portion 262 derived from the second electrode line 220 and the third electrode line 230 and extended from the first electrode portion 261 while having a size that is smaller than the first electrode portion 261 such that at least one step difference (refer to 330 of FIG. 8) is formed on a plane.

[0100] Here, the step difference 330 includes a step difference corner 331 that is formed at a portion where an exterior side 314 of the first electrode portion 261 and an exterior side 324 of the second electrode portion 262 intersect each other at about 90 degrees, and in the notching of the process 3, notching may be additionally carried out to form an exterior circumference recess portion 340 having a shape formed by inwardly recessing a part of the first electrode portion 261 and a part of the second electrode portion 262.

[0101] Hereinbefore, the certain exemplary embodiments of the present invention have been described and illustrated, however, it is apparent to a person with ordinary skill in the art that the present invention is not limited to the exemplary embodiments as described, and may be variously modified and transformed without departing from the spirit and scope of the present invention. Accordingly, the modified or transformed exemplary embodiments as such are not to be understood separately from the technical ideas and aspects of the present invention, and the modified exemplary embodiments are within the scope of the claims of the present invention.

INDUSTRIAL APPLICABILITY

[0102] As described above, according to the method for manufacturing an electrode for a rechargeable battery according to the exemplary embodiments of the present invention, a slot die that is alternately disposed in the first coating line and the second coating line may coat an electrode line in a zigzag shape, and thus the electrode line includes an irregular shape including an uncoated region, thereby saving an amount of electrode slurry that would be coated on the uncoated region.

[0103] In addition, since notching is carried out excluding the uncoated region where the electrode slurry is not coated, the amount of slurry wasted during the notching can be minimized, thereby preventing waste of expensive organic/inorganic materials such as an electrode active material, a binder, a solvent, and a conductive material.