Lithium secondary battery and manufacturing method thereof

A lithium secondary battery includes a cylindrical battery case provided with electrode caps at both end portions thereof. An electrode body impregnated with a nonaqueous electrolyte solution is contained in the battery case and includes a positive electrode, a negative electrode, and a separator, with the positive electrode and the negative electrode being wound or laminated through the separator. An elastic body is disposed between the battery case and the electrode caps, with portions in which the battery case contacts the elastic body being brought into press-contact to form a caulked portion to seal the battery case. R_body(mm) is a diameter of a body part of the battery case and R_top(mm) is a diameter of the caulked portion, wherein R_body and R_top fulfill a relationship of R_bodyR_top.