Lithium secondary battery

Disclosed is a lithium secondary battery (100) which comprises a separator (112) comprising a substrate and a coating layer, the coating layer comprising an inorganic compound, a polymer and an organic/inorganic bonding silane compound having a first reactive functional group; and an electrode (113, 114) having contact with the coating layer, the electrode comprising an active material and a binder having a second reactive functional group, wherein the first reactive functional group is able to react with the second reactive functional group thereby forming a chemical bond. Also disclosed is a lithium secondary battery (100) in which the chemical reaction has occurred.