Electrode assembly manufacturing method including separator cutting process
Provided is an electrode assembly manufacturing method including a process of cutting a separator included in an electrode assembly to have a margin protruding from an electrode plate. The method includes a first process of manufacturing one type of basic unit sheets having a structure in which electrode materials and separator materials, which are the same in number, are alternately stacked, or two or more types of basic unit sheets having a structure in which electrode materials and separator materials, which are the same in number, are alternately stacked, and a second-A process of cutting a portion of a margin area of the separator materials, which are not covered with the electrode materials, such that the separator materials of the basic unit sheets protrude over a specific distance from edges of the electrode materials.
1. An electrode assembly manufacturing method comprising:
a first process of manufacturing one type of basic unit sheets having a structure in which electrode materials and separator materials, which are the same in number, are alternately stacked, or two or more types of basic unit sheets having a structure in which electrode materials and separator materials, which are the same in number, are alternately stacked;
a second-B process of forming an electrode assembly by repeatedly stacking unit structures formed by cutting the one type of the basic unit sheets at regular intervals, or by stacking, in a predetermined order, two or more types of unit structures formed by cutting each of the two or more types of the basic unit sheets at the regular intervals; and
after stacking the unit structures formed by the second-B process, a third process of cutting a portion of a margin area of the separator materials, which are not covered with the electrode materials, such that the separator materials included in the electrode assembly protrude over a specific distance from edges of the electrode materials,
wherein the one type of the basic unit sheets have a four-layer structure formed by sequentially stacking a first electrode material, a first separator material, a second electrode material, and a second separator material, or a structure formed by repeatedly stacking the four-layer structure,
the two or more types of the basic unit sheets are stacked one by one in a predetermined order to form the four-layer structure or a structure formed by repeatedly stacking the four-layer structure, and
in the third process, only the separator materials are held between an upper mold and a lower mold of a mold cutter thereby applying pressure to the separator materials so as to fix adhere the separator materials to each other and to cut the portion of the margin area of the separator materials fixed and held by the upper mold and the lower mold by using a cutting block of the mold cutter that is moveable relative to the upper mold and the lower mold.
2. The electrode assembly manufacturing method of claim 1 , wherein the electrode assembly includes 10 or fewer unit structures in the second-B process.
3. The electrode assembly manufacturing method of claim 1 , wherein the distance ranges from 1.0 mm to 2.0 mm.
4. The electrode assembly manufacturing method of claim 1 , wherein the distance is 38 times to 75 times greater than a thickness of the separator materials.
5. The electrode assembly manufacturing method of claim 1 , wherein adhesive force between an electrode and a separator adjacent to the electrode in the unit structures is greater than adhesive force between the unit structures in the electrode assembly.
6. The electrode assembly manufacturing method of claim 1 , wherein both surfaces of the separator materials included in the basic unit sheets and disposed between two of the electrode materials are coated with a coating material having adhesive force, and only a surface of the other separator materials contacting the electrode materials is coated with the coating material having adhesive force.
7. The electrode assembly manufacturing method of claim 1 , wherein an electrode of the unit structures is adhered to a separator adjacent to the electrode.