Method of preparing electrode assembly and electrode assembly prepared using the method
View Patent ↗Provided are a method of preparing an electrode assembly, in which both sides of a single current collector are coated to form an anode and a cathode, and the current collector is then bent into a vertical sectional zigzag shape and integrated in a state of disposing a separator at interfaces between facing electrode patterns, an electrode assembly prepared by the above method, and a secondary battery comprising the electrode assembly.
1. A method of preparing an electrode assembly, the method comprising:
preparing a single current collector;
coating both sides of the single current collector with a cathode active material and an anode active material alternating with one another to integrally form a plurality of anode patterns and cathode patterns on each side of the single current collector and a plurality of non-coating portions on which the cathode active material and the anode active material are not coated;
bending the plurality of non-coating portions into a vertical sectional zigzag shape to form bent non-coating portions;
disposing a separator at respective interfaces between the cathode patterns and the anode patterns that face each other by the bending, and folding the single current collector; and
cutting the bent non-coating portions.
2. The method of claim 1 , wherein the electrode assembly is a layered electrode assembly.
3. The method of claim 1 , further comprising drying and pressing the plurality of anode patterns and cathode patterns before the bending.
4. The method of claim 1 , wherein widths of the cathode pattern and the anode pattern are same.
5. The method of claim 1 , wherein a width of the non-coating portion is in a range of 5% to 10% based on a total width of the cathode patterns or the anode patterns.
6. The method of claim 1 , wherein a marking for facilitating the bending is formed in the non-coating portions.
7. The method of claim 1 , further comprising non-coating portions, on which the electrode active materials are not coated, at one side end or both side ends of the current collector to attach electrode leads.
8. The method of claim 1 , wherein the separator is a porous thin film formed of an insulating material.
9. The method of claim 1 , wherein a lamination structure, in which unit cells composed of the cathode patterns/the separator/the anode patterns are alternatingly stacked, is formed after the folding.
10. The method of claim 1 , wherein the cutting is performed by a cutting or punching method.
11. An electrode assembly prepared by the method of claim 1 .
12. A secondary battery comprising the electrode assembly of claim 11 .
13. The secondary battery of claim 12 , wherein the secondary battery is a lithium-ion polymer secondary battery.
14. The method of claim 4 , wherein a width of the non-coating portions is in a range of 5% to 10% based on a total width of the cathode patterns or the anode patterns.
15. The method of claim 6 , wherein the marking comprises one or more holes that are perforated at predetermined spaced intervals along a portion to be folded.