Abstract: An electrode assembly includes a plurality of unit cells, each including a positive electrode, a negative electrode, and a separator disposed therebetween, and a single separation sheet disposed between the unit cells while surrounding side surfaces thereof. First and second stack parts of unit cells are wound with the separation sheet from each end of the separation sheet toward the middle of the separation sheet, a facing unit cell has one surface that contacts the first stack part with the separation sheet between the one surface of the facing unit cell and the first stack part and the other surface that contacts the second stack part with the separation sheet between the other surface of the facing unit cell and the second stack part, and the unit cells are stacked such that electrodes having opposite polarities are disposed in contact with each other with the separation sheet therebetween.

Abstract: Provided is a battery cell having a structure in which outer circumferential sides of a cell case are sealed by heat fusion in a state in which an electrode assembly including a cathode, an anode, and a separator is housed in a cell case together with an electrolyte solution, wherein the electrode assembly and the cell case have a structure in which both ends at positions opposite to each other are together curved in the same direction so that a curved surface is formed on an outer surface of the battery cell, and at least one of the heat-fused outer circumferential sides of the cell case is curved to adhere to a curved surface while forming an inner surface.

Abstract: Disclosed herein is an electrode assembly including a plurality of unit cells, each of which is configured to have a structure including a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, and a single separation sheet disposed between the unit cells while surrounding side surfaces of the unit cells, wherein the unit cells include unit cells wound together with the separation sheet from one end of the separation sheet toward the middle of the separation sheet to constitute a first stack part, unit cells wound together with the separation sheet from the other end of the separation sheet toward the middle of the separation sheet to constitute a second stack part, and a facing unit cell having one surface that contacts the first stack part in the state in which the separation sheet is disposed between the one surface of the facing unit cell and the first stack part and the other surface that contacts the second stack part in the state in