Cylindrical lithium-ion battery

摘要

A cylindrical lithium-ion battery with excellent safety where abnormal heat generation and remarkable deformation of a battery container do not occur even at an abnormal time is provided. When an average diameter of a winding group 6 is A mm, an inner diameter of the battery container 5 is B mm, a longitudinal length of the winding group 6 except for lead pieces extending from the winding group 6 is H mm, and the number of windings where a layer of one unit comprising a negative electrode member/separator/negative electrode member/separator is wound around a shaft core 11 is W, a calculation value K obtained by a formula; K = (B - A) x 10000/(W x H) is set to 0.89 or more. When the calculation value K is 0.89 or more, a gap (B - A) between an outer periphery of the winding group 6 and an inner periphery of the battery container 5 that enables the winding group 6 to expand in its diameter direction at an abnormal time is properly secured.