Electrolyte for lithium ion rechargeable battery and lithium ion rechargeable battery comprising the same

1. An electrolyte for a lithium ion rechargeable battery, consisting of:

a non-aqueous organic solvent;

a lithium salt;

at least one monomer selected from a group consisting of an acrylate monomer, epoxy monomer, isocyanate monomer and prepolymers thereof;

an organic peroxide or an azo-based polymerization initiator; and

triphenyl phosphate,

wherein the triphenyl phosphate has a concentration of 5 to 10 wt %, based on the total weight of the electrolyte.

2. The electrolyte of claim 1 , wherein the lithium salt is at least one selected from a group consisting of LiPF 6 , LiBF 4 , LiSbF 6 , LiAsF 6 , LiClO 4 , LiAlO 4 , LiAlCl 4 , LiCF 3 SO 3 , LiN(SO 2 CF 3 ) 2 , LiC 4 F 9 SO 3 , LiN(SO 2 C 2 F 5 ) 2 , LiN(C x F 2x+1 SO 2 )(C y F 2y+1 SO 2 ) (wherein, each of x and y is an integer), LiCl and Lil.

3. The electrolyte of claim 2 , wherein the lithium salt has a concentration in the range of 0.6M to 2.0M.

4. The electrolyte of claim 1 , wherein the non-aqueous organic solvent is at least one selected from a group consisting of a carbonate, an ester, an ether, and a ketone.

5. The electrolyte of claim 4 , wherein the carbonate is at least one selected from a group consisting of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethylmethyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, ethylene carbonate, propylene carbonate and butylene carbonate.

6. The electrolyte of claim 5 , wherein the carbonate solvent is a mixed solvent of a cyclic carbonate and a linear chain carbonate.

7. The electrolyte of claim 4 , wherein the non-aqueous organic solvent is a mixed solvent of a carbonate solvent and an aromatic hydrocarbon-based organic solvent.

8. The electrolyte of claim 7 , wherein the aromatic hydrocarbon-based organic solvent is an aromatic compound represented by Formula 2:

wherein R1 is a halogen atom or an alkyl group having 1 to 10 of carbon atoms, and

wherein n is an integer between and including 0 to 6.

9. The electrolyte of claim 8 , wherein the aromatic hydrocarbon-based organic solvent is at least one solvent selected from a group consisting of benzene, fluorobenzene, chlorobenzene, toluene, fluorotoluene, trifluorotoluene, xylene, and mixtures thereof.

10. The electrolyte of claim 9 , wherein a volume ratio of the carbonate solvent to the aromatic hydrocarbon-based organic solvent is between 1:1 and 30:1.

11. The electrolyte of claim 4 , wherein the ether is tetrahydrofuran or 2-methyl tetrahydrofuran.

12. The electrolyte of claim 4 , wherein the ester is at least one solvent selected from a group consisting of methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate and γ-butyrolactone.

13. The electrolyte of claim 4 , wherein the ketone is polymethylvinyl ketone.

14. The electrolyte of claim 1 , wherein the monomer has a concentration of about 0.1 to about 5 wt % based on a total weight of the electrolyte.

15. An electrolyte of claim 1 , wherein the organic peroxide has a concentration of about 0.01 to about 1.0 wt % based on a total weight of the monomer.

16. The electrolyte of claim 1 , wherein the peroxide is at least one peroxide selected from a group consisting of isobutyl peroxide, lauryl peroxide, lauroyl peroxide, dilauroyl peroxide, didecanoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, benzoyl peroxide, m-toluoyl peroxide, tert-butyl peorxy-2-ethyl hexanoate, tert-butyl peroxy pivalate, tert-butyl peroxy neodecanoate, diisopropyl peroxy dicarbonate, diethoxy peroxy dicarbonate, bis-(4-tert-butylcyclohexyl) peroxy dicarbonate, dimethoxy isopropyl peroxy dicarbonate, dicyclohexyl peroxy dicarbonate, and 3,3,5-trimethylhexanoyl peroxide.

17. A lithium ion rechargeable battery, comprising:

a cathode including a cathode active material that is capable of reversible lithium ion intercalation/deintercalation;

an anode including an anode active material that is capable of reversible lithium ion intercalation/deintercalation; and

an electrolyte,

wherein the electrolyte consists of:

a non-aqueous organic solvent;

a lithium salt;

at least one monomer selected from a group consisting of an acrylate monomer, epoxy monomer, isocyanate monomer and prepolymers thereof;

an organic peroxide or an azo-based polymerization initiator; and

triphenyl phosphate,

wherein the triphenyl phosphate has a concentration of 5 to 10 wt %, based on the total weight of the electrolyte.

18. The lithium ion rechargeable battery of claim 17 , wherein the battery is a lithium ion polymer battery.