TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The lithium salt comprises lithium chloride, lithium bromide, lithium iodide, lithium perchlorate, lithium tetrafluoroborate, lithium boron compound (LiB10Cl10), lithium hexafluorophosphate, lithium trifluoromethanesulfonate, lithium hexafluoroarsenate, lithium hexafluroantimonate, lithium hexafluorophosphate, lithium tetrachloroaluminate, lithiumtrifluoromethanesulfonate, lithium bis(trifluoromethanesulfonyl)imide, lithium-chloro borane, lithium tetraphenyl borate, and lithium imide. The lithium secondary battery further comprises an anode comprising a cathode active material having a lithium metal phosphate compound of formula (Li1+aM(PO4-b1)Xb1) and (Li1+aFe1-xM1x(PO4-b1)Xb1) (I), and a cathode comprising an anode active material including amorphous carbon. (I) has olivine crystal structure. The amorphous carbon includes hard carbon and/or soft carbon.M = metal of Group 12;M1 = Al, Mg, Ni, Co, Mn, Ti, Ga, Cu, V, Nb, Zr, Ce, In, Zn or Y;X = F, S or N;a = -0.5 to 0.5;b = 0-0.1; andx = 0-0.5.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The dioxolane based solvent includes 1,3-dioxolane (preferred), 4,5-diethyl-dioxolane, 4,5-dimethyl-dioxolane, 4-methyl-1,3-dioxolane, and 4-ethyl-1,3-dioxolane. The ether-based solvent includes dimethyl ether (preferred), tetrahydrofuran, and 2-methyl tetrahydrofuran. The dioxolane based solvent is present in an amount of 15-35 wt.%. The ether-based solvent is present in an amount of 65-85 wt.%. The electrolyte further comprises a carbonate type solvent. A weight ratio of the dioxolane based solvent and the ether-based solvent is 60:40-90:10. The carbonate type solvent includes ethylene carbonate, polypropylene carbonate, 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, and 2,3-pentylene carbonate. A linear carbonate-based solvent is added to the carbonate type solvent in a volume ratio of 1:4-4:1, and includes dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethyl methyl carbonate, methylpropyl carbonate, and ethyl propyl carbonate.