TECHNOLOGY FOCUS - ELECTRONICS - Preferred Device: The lithium secondary battery has the electrolyte, and an anode (13) containing an anodic active material intercalating and deintercalating the lithium ion reversibly.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Salt: The lithium salt is lithium phosphorus hexafluoride (LiPF6), lithium boro tetrafluoride (LiBF4), lithium antimony hexafluoride (LiSbF6), lithium arsenic hexafluoride (LiAsF6), lithium oxychlorate (LiClO4), lithium trifluoro sulfate (LiCF3SO3), lithium nitride complex (LiN(SO2CF3)2, LiN(SO3CF3)2 or LiN(SO2C2F5)2), lithium sulfate complex (LiC(SO2CF3)3, or LiC4F9SO3), lithium-aluminum oxide (LiAlO4), lithium-aluminum chloride (LiAlCl4), lithium chloride (LiCl), and/or lithium iodide (LiI). Preferred Materials: The anodic active material is of formula: LixMn1MnyMyA2, LixMn1MnyMyO2MyOzXz, LixMn2O4OzXz, LixMn2MnyMyM'zA4, LixCo1CoyMyA2, LixCo1CoyMyO2OzXz, LixNi1NiyMyA2, LixNi1NiyMyO2OzXz, LixNi1NiyCoyO2OzXz, LixNi1NizCoyMzAa, LixNi1NizCoyMzO2OXa, LixNi1NizMnyMzAa, or LixNi1NizMnyMzO2OXa, where x is 0.9-1.1, y is 0-0.5, z is 0-0.5, a is 0-2, M and M'are magnesium, aluminum, cobalt, potassium, sodium, calcium, silicon, titanium, tin, vanadium, germanium, gallium, boron, arsenic, zirconium, manganese, chromium, iron, strontium or rare earth metal, A is oxygen, fluorine, sulfur or phosphorus, or X is fluorine, sulfur or phosphorus. The anodic active material is crystalline carbon, amorphous carbon, carbon complex, carbon fiber, lithium metal or lithium alloy.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Carbonates: The halo ethylene carbonate is chosen from fluoroethylene carbonate, 1,1-difluoroethylene carbonate, 1,2-difluoroethylene carbonate, 1,1,2-tri fluoro ethylene carbonate, 1,1,2,2-tetrafluoroethylene carbonate, chloroethylene carbonate, 1,1-dichloroethylene carbonate, 1,2-dichloroethylene carbonate, 1,1,2-trichloroethylene carbonate, 1,1,2,2-tetrachloroethylene carbonate, bromoethylene carbonate, 1,1-dibromoethylene carbonate, 1,2-dibromoethylene carbonate, 1,1,2-tribromoethylene carbonate, 1,1,2,2-tetrabromoethylene carbonate, iodo ethylene carbonate, 1,1-diiodo ethylene carbonate, 1,2-diiodo ethylene carbonate, 1,1,2-triiodoethylene carbonate and 1,1,2,2-tetraiodoethylene carbonate. The carbonate is dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl methyl carbonate, ethyl propyl carbonate, ethylene carbonate, polypropylene carbonate, 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate and 2,3-pentylene carbonate. The carbonate is the mixed solvent of the linear carbonate and cyclic carbonate. Preferred Borate: The trialkylsilyl borate is chosen from tris(trimethyl silyl) borate, tris(triethylsilyl) borate, tris(tripropylsilyl) borate, tris(tributyl silyl) borate, tris(tripentyl silyl) borate, tris(trihexyl silyl) borate, tris(triheptyl silyl) borate and tris(trioctyl silyl) borate. Preferred Solvents: The non-aqueous organic solvent is carbonate, ester or ketone. The non-aqueous organic solvent is the mixed solvent of the aromatic hydrocarbon-based organic solvent and carbonate-type solvent. The aromatic hydrocarbon-based organic solvent is aromatic compound of formula (2), such as benzene, fluorobenzene, chlorobenzene, bromobenzene, toluene, xylene and/or mesitylene.R=1-10C haloalkyl;andq=0-6.Preferred Properties: The content of halo ethylene carbonate is 0.1-10 weight%, and trialkylsilyl borate is 0.2-1 weight%. The volume ratio of carbonate-type solvent and aromatic hydrocarbon-based organic solvent is 1:1 or 30:1. The concentration of lithium salt is 0.6-2M. EXAMPLE - Carbon, lithium-cobalt oxide (LiCoO2) and polyvinylidene fluoride in weight ratio of 92:4:4 were dispersed in N-methyl pyrrolidone to form bipolar slurry. The slurry was coated on an aluminum foil of thickness 20 mu m and rolled to form anode. A carboxy methyl cellulose, graphite and styrene butadiene rubber in weight ratio of 96:2:2 were dispersed in water to form cathode active material slurry. The obtained slurry was coated on a copper foil of thickness 15 mu m and rolled to form cathode. A fluoroethylene carbonate (3 weight%) and tris(trimethylsilyl)borate (1 weight%) were dissolved in ethylene carbonate/ethyl methyl carbonate and dimethyl carbonate in volume ratio of 1:1:1 to form electrolyte. The obtained anode and cathode were inserted into a cylindrical can and separated by a polyethylene material of thickness 20 mu m, and electrolyte was injected to form lithium secondary battery having excellent capacity, charge/discharge efficiency and durability.