Secondary battery

1. A secondary battery comprising:

an electrode assembly comprising first electrode plates and second electrode plates, alternately stacked with a separator therebetween, and first electrode tabs overlapping one another at a same position and outwardly protruding from a short side surface of opposite short side surfaces of the electrode assembly, the first electrode tabs being uncoated portions of the first electrode plates, and a first fixing tape adhered between the separator positioned at a long side surface of opposite long side surfaces of the electrode assembly and an outer surface of an outermost first electrode tab of the first electrode tabs, the first fixing tape having an L-shaped configuration such that a first end of the first fixing tape is located on the separator and a second end of the first fixing tape is located on the short side surface of the electrode assembly;

a first collector portion welded to the first electrode tabs of the electrode assembly; and

a case accommodating the electrode assembly and the first collector portion.

2. The secondary battery of claim 1 , wherein the first electrode tabs outwardly protrude from the short side surface of the electrode assembly and are collected to be welded to the first collector portion.

3. The secondary battery of claim 2 , wherein the first fixing tape comprises a first region adhered to an outer surface of the separator, and a second region adhered to the outer surface of the outermost first electrode tab of the first electrode tabs.

4. The secondary battery of claim 3 , wherein the second region of the first fixing tape is bent toward the one short side surface of the electrode assembly to cover a portion of the one short side surface.

5. The secondary battery of claim 2 , wherein the electrode assembly further comprises a plurality of second electrode tabs being uncoated portions of the second electrode plate and outwardly protruding from the other short side surface of the opposite short side surfaces of the electrode assembly.

6. The secondary battery of claim 5 , wherein a second fixing tape is adhered between an outer surface of the separator and an outer surface of an outermost second electrode tab of the second electrode tabs.

7. The secondary battery of claim 5 , wherein the separator extends perpendicular to a direction in which the first electrode tabs and the second electrode tabs respectively located in the first electrode plate and the second electrode plate protrude, and is bent in a Z-shaped configuration.

8. The secondary battery of claim 6 , wherein the second fixing tape comprises a first region adhered to an outer surface of the separator and a second region adhered to an outer surface of an outermost second electrode tab of the second electrode tabs.

9. The secondary battery of claim 5 , wherein the first fixing tape comprises two tapes adhered between a first-side end portion of the long side surface of the electrode assembly and the outermost first electrode tab of the first electrode tabs and between a second-side end portion of the long side surface of the electrode assembly and an outermost second electrode tab of the second electrode tabs, respectively, and the electrode assembly further comprises another fixing tape comprising two tapes adhered between a first-side end portion of the other long side surface of the opposite long side surfaces of the electrode assembly and another outermost first electrode tab of the first electrode tabs and between a second-side end portion of the another long side surface of the electrode assembly and another outermost second electrode tab of the second electrode tabs, respectively.

10. The secondary battery of claim 1 , wherein the first fixing tape comprises polyimide, polypropylene, or polyethylene terephthalate.