Negative electrode active material for lithium secondary battery and lithium secondary battery comprising the same

1. A negative electrode active material for a lithium secondary battery comprising:

(a) a core including a carbon-based material; and

(b) an organic polymer coating layer uniformly formed on an entire surface of the core, wherein the organic polymer coating layer is formed of a polymer compound, wherein the polymer is selected from the group consisting of an epoxy compound containing a fluorine component, and a silane-based compound containing a fluorine component,

wherein the epoxy compound containing a fluorine component comprises a compound expressed as the following Chemical Formula 1:

and

wherein the silane-based compound containing a fluorine component comprises a compound expressed as the following Chemical Formula 3:

CF 3 —(CF 2 ) o —(CH 2 ) p —SiCl 3   [Chemical Formula 3]

(where o is an integer between 1 and 12, and p is an integer of 1 or 2), and

wherein the carbon-based material is one or more selected from the group consisting of natural graphite, artificial graphite, fibrous graphite, amorphous carbon, and amorphous carbon-coated graphite.

2. The negative electrode active material of claim 1 , wherein the polymer compound has a content of a fluorine component of 50 wt % or more.

3. The negative electrode active material of claim 2 , wherein the polymer compound has a content of a fluorine component ranging from 50 wt % to 95 wt %.

4. The negative electrode active material of claim 1 , wherein the silane-based compound containing a fluorine component is trichloro(1H,1H,2H,2H-perfluorooctyl)silane or perfluorodecyltrichlorosilane.

5. The negative electrode active material of claim 1 , wherein the organic polymer coating layer is formed of a single layer or a multilayer.

6. The negative electrode active material of claim 1 , wherein a thickness of the organic polymer coating layer is in a range of 50 nm to 100 nm.

7. The negative electrode active material of claim 1 , wherein the organic polymer coating layer is formed by using a chemical vapor deposition method, a solvent evaporation method, a coprecipitation method, a precipitation method, a sol-gel method, an adsorption filtration method, or a sputtering method.

8. A lithium secondary battery comprising:

(i) a positive electrode comprising a positive electrode active material;

(ii) a negative electrode comprising the negative electrode active material described in claim 1 ;

(iii) a separator; and

(iv) an electrolyte.

9. The lithium secondary battery of claim 8 , wherein (ii) the negative electrode is prepared by coating a current collector with the negative electrode active material and drying, or by casting a composition including the negative electrode active material and a binder on a separate support and laminating a film detached from the support on a current collector.