| abstract |
A cylindrical lithium secondary battery capable of ensuring safety by preventing damage to a porous heat-resisting layer, and realizing an excellent battery characteristics. The cylindrical lithium secondary battery comprises electrode groups each consisting of, all rolled up, a band-form anode, a band-form cathode, and a porous heat-resisting layer and a separator interposed between them, wherein the anode includes an anode core material and anode active materials supported on the opposite surfaces thereof, the cathode includes a cathode core material and cathode active materials supported on the opposite surfaces thereof, and the thickness A of the porous heat-resisting layer and the thickness B of the side wall of the battery can satisfy 0.005 ≤ A/B ≤ 0.1. |