Electrode sheet cutting apparatus including upper cutter and lower cutter and electrode sheet cutting method using the same

1 . An electrode sheet cutting apparatus comprising:

an upper cutter configured to be located above an electrode sheet, the upper cutter being configured to cut the electrode sheet;

a lower cutter facing the upper cutter, the lower cutter being configured to engage the upper cutter to cut the electrode sheet; and

an electrode sheet support located between the upper cutter and the lower cutter, the electrode sheet support being configured to support the electrode sheet, the electrode sheet support being provided with a through hole configured to overlie a cutting portion of the electrode sheet at which the upper cutter and the lower cutter are configured to engage each other,

wherein the upper cutter and the lower cutter are each configured to cut the electrode sheet with increasing lengths of the upper cutter and the lower cutter contacting the electrode sheet as cutting proceeds from first ends of the upper cutter and the lower cutter to second ends of the upper cutter and the lower cutter in a direction parallel to a longitudinal direction of the upper cutter and the lower cutter,

wherein the apparatus is configured to cut the electrode sheet to form an electrode tab protrusion,

wherein the upper cutter and the lower cutter are configured to first cut the electrode sheet at a position at which the electrode tab protrusion is to be formed, and to last cut the electrode sheet at a position farthest from the electrode tab protrusion, and

wherein the apparatus is configured to apply a stress to the electrode sheet between 0.1 N/m 2 and 1.0 N/m 2 ,

wherein the apparatus is configured to cut the electrode sheet with increasing lengths of the upper cutter and the lower cutter contacting the electrode sheet from a portion adjacent to a middle part of the electrode sheet at the first ends of the upper cutter and the lower cutter to a peripheral portion of the electrode sheet at the second ends of the upper cutter and the lower cutter, and

wherein the middle part of the electrode sheet is spaced apart from all peripheral edges of the electrode sheet, and the first ends of the upper cutter and the lower cutter overlie the through hole of the electrode sheet support, the through hole being in a middle part of the electrode sheet support that is spaced apart from all peripheral edges of the electrode sheet support.

2 . The electrode sheet cutting apparatus according to claim 1 , wherein the upper cutter and the lower cutter are each configured to apply an identical force to opposite surfaces of the electrode sheet.

3 . The electrode sheet cutting apparatus according to claim 1 , wherein the upper cutter and the lower cutter are each configured to move towards opposite surfaces of the electrode sheet at an identical speed.

4 . The electrode sheet cutting apparatus according to claim 1 , wherein the upper cutter and the lower cutter each have an identical shape or a symmetrical shape to one another.

5 . The electrode sheet cutting apparatus according to claim 4 , wherein when the upper cutter and the lower cutter are in an initial position, a distance between the upper cutter and the lower cutter incrementally increases from one side of the apparatus toward another side of the apparatus.

6 . An electrode sheet cutting method comprising:

disposing the electrode sheet on the electrode sheet support, such that the through hole of the electrode sheet support overlies a portion of the electrode sheet at which the electrode sheet is to be cut; and

cutting the electrode sheet using the upper cutter and the lower cutter according to claim 1 .

7 . The electrode sheet cutting method according to claim 6 , wherein, during the cutting, the electrode sheet is cut in a longitudinal direction or a direction perpendicular thereto to form a single electrode assembly or is cut in a concave-convex shape to form an electrode tab.

8 . The electrode sheet cutting method according to claim 7 , wherein the electrode tab is formed during the cutting, and the upper cutter and the lower cutter first cut a protrusion of the electrode tab and then cut a place on the electrode sheet farthest from the protrusion of the electrode tab.

9 . The electrode sheet cutting method according to claim 8 , wherein the place on the electrode sheet farthest from the protrusion of the electrode tab is another cutting portion of the electrode sheet.