Patent attributes
A lithium secondary battery includes a cathode, an anode, a separator interposed between the cathode and the anode, and a non-aqueous electrolytic solution obtained by dissolving lithium salt to a non-aqueous solvent. The separator includes a porous substrate having pores; and a porous coating layer located on at least one surface of the porous substrate and having inorganic particles and a binder polymer, the inorganic particles being connected and fixed to each other by means of the binder polymer, the porous coating layer having pores therein formed by interstitial volumes among the inorganic particles. The non-aqueous solvent is a high-viscous non-aqueous solvent having a viscosity of 1.4 cP or above at 25° C. This lithium secondary battery gives improved safety and excellent charging/discharging characteristics since it has the high-viscous non-aqueous solvent and the separator with good wettability against the solvent.
