Corrosion resistant tube for secondary battery and secondary battery comprising the same

1. A secondary battery, comprising:

(i) an electrode assembly comprising: a positive electrode, a negative electrode and a separator;

(ii) a metal can,

wherein the electrode assembly is built in the metal can; and

(iii) a corrosion resistant tube, consisting of one layer, said layer comprising:

a volatile corrosion inhibitor,

wherein the volatile corrosion inhibitor comprises NaNO 2 and a polymer resin; and

a base resin, wherein the base resin is a single material selected from the group consisting of polyethylene terephthalate (PET), nylon and polybutylene terephthalate (PBT), or a mixture of two or more types among these;

wherein the corrosion resistant tube is coated on an outer circumference surface of the metal can,

wherein the volatile corrosion inhibitor is included in 2 to 10 parts by weight based on 100 parts by weight of the base resin.

2. The secondary battery of claim 1 , wherein the polymer resin is one selected from the group consisting of polypropylene (PP), polybutylene terephthalate, polyethylene, polyethylene terephthalate, teflon, polytetrafluoroethylene, rayon, mixed yarn, polyviscose and polynosic nylon, or a mixture of two or more types among these.

3. The secondary battery of claim 1 , wherein NaNO 2 is included within 10 parts by weight based on 100 parts by weight of the polymer resin.

4. The secondary battery of claim 1 , further comprising a washer mounted on an upper part of a cap assembly installed on an opened upper part of the metal can.

5. The secondary battery of claim 1 , wherein a thickness of the corrosion resistant tube for a secondary battery is from 0.05 mm to 0.1 mm.

6. The secondary battery of claim 1 , wherein gamma iron trioxide (γ-Fe 2 O 3 ) is formed at an end of the metal can.

7. The secondary battery of claim 6 , wherein the gamma iron trioxide is formed to a thickness of 10 Å to 1000 Å.

8. The secondary battery of claim 4 , wherein the metal can is a cylindrical can, and in the cap assembly, a positive electrode protruded terminal connected to the electrode assembly is formed in the middle.

9. The secondary battery of claim 4 , wherein the metal can is a rectangular can, and in the cap assembly, a negative electrode protruded terminal connected to an electrode terminal is formed in the middle.

10. The secondary battery of claim 4 , wherein the washer is fixed on an upper surface of the cap assembly through adhesion or mechanical binding.

11. The secondary battery of claim 4 , wherein the washer is a corrosion inhibiting washer including a volatile corrosion inhibitor and a base resin.