Patent ID: 8529801

Claim:
A negative active material for a rechargeable lithium battery, comprising: an active material comprising a polymer having a tensile strength of at least 40 MPa substantially uniformly mixed therewith; and a separator, wherein the polymer is a compound selected from the group consisting of the following Chemical Formulae: wherein, R 1 to R 19 are independently selected from the group consisting of hydrogen, an alkyl, a haloalkyl, an alkoxy, acrylic acid including Li or Na, an aryl, and a halogen, A 1 to A 7 are independently selected from the group consisting of O, CO, SO 2 , and CR 41 R 42 , where R 41 and R 42 are independently an alkyl, a haloalkyl, or phenyl, n 1 and n 4 are independently from 1 to 3, n 2 , n 3 , and n 5 to n 12 are independently from 1 to 4, a 1 to a 11 are independently from 1 to 5, p and q independently range from 0.01 to 0.99, and m 1 to m 3 independently range from 100 to 10,000; wherein the active material is selected from the group consisting of: a lithium vanadium-based oxide, a tin oxide (SnO x , 0≦x≦2), a silicon oxide (SiO x , 0<x<2), and a combination thereof.