NOVELTY - A solvent-free polymer electrolyte comprises a porous film having a first and second surface; and an electrolyte present in the pores of porous film and comprising second oligomer and a lithium salt.    USE - In secondary battery (claimed). For high performance batteries used in mobile communications, portable electronic devices, electric automobiles and capacitors.    ADVANTAGE - The solvent-free polymer electrolyte is prepared by impregnation of a porous film with a viscous oligomer under vacuum, use of an electrolyte solution is not required. Thus, the solvent-free polymer electrolyte is not accompanied by problems caused by leakage or evaporation of an electrolyte solution. Since the viscous oligomer is contained in pores, higher ionic conductivity is accomplished, as compared to a conventional solvent-free polymer electrolyte. The solvent-free polymer electrolyte does not exhibit rapid reduction in ionic conductivity even at low temperature, and thus, provides high electrochemical stability. Thus, use of the solvent-free polymer electrolyte in a secondary battery such as a lithium secondary battery can solve the problems of a conventional secondary battery employing a conventional gel-type polymer electrolyte or solvent-free polymer electrolyte. The solvent-free polymer electrolyte used in a battery requiring high voltage because of its high electrochemical stability, and thus, is expected to be widely used as a polymer electrolyte for a secondary battery; and exhibits excellent safety.    DETAILED DESCRIPTION - A solvent-free polymer electrolyte comprises a porous film having a first and second surface; and an electrolyte present in the pores of porous film and comprising second oligomer and a lithium salt. The porous film comprises a reticulated network of channels formed between pores on the first and second surfaces, and is made of a mixture comprising a first polymer and second oligomer. The first polymer is at least one of poly (vinylidene fluoride-co-hexafluoropropylene) copolymers, polyvinylidenefluorides, polymethylmethacrylates, polyacrylonitriles, polyethyleneoxides or celluloses having a polyether chain. The second oligomer is at least one of poly (ethylene oxide-co-ethylene carbonate) copolymers with at least one terminal groups substituted by a halogen atom, or polyethyleneglycols with at least one terminal groups substituted by a halogen atom. Each of the first polymer and second oligomer are present in the mixture to form a single phase. An INDEPENDENT CLAIM is included for a secondary battery comprising an anode having a carbonaceous material; a cathode having a compound enabling intercalation and deintercalation of lithium; and the solvent-free polymer electrolyte interposed between the cathode and anode.