NOVELTY - A lithium-ion battery (10) consists of a positive electrode plate (11) including a positive electrode collector and a positive electrode active material layer formed on surface of the positive electrode collector, a negative electrode plate (12) including a negative electrode collector and a negative electrode active material formed on surface of the negative electrode collector, a separator (18) for separating positive electrode plate and negative electrode plate, and a nonaqueous electrolytic solution containing nonaqueous solvent and electrolytic salt.    USE - Lithium-ion battery. Uses include but are not limited to mobile telephone, notebook personal computer, personal digital assistance, electric vehicle, hybrid electric vehicle and electric tool.    ADVANTAGE - The lithium-ion battery has excellent cycle characteristics and initial charge/discharge efficiency, and suppressed leak test defects in which positive and negative electrodes short circuit through lithium metal present in vicinity of end portion of separator.    DETAILED DESCRIPTION - A lithium-ion battery consists of a positive electrode plate including a positive electrode collector and a positive electrode active material layer formed on surface of the positive electrode collector, a negative electrode plate including a negative electrode collector and a negative electrode active material formed on surface of the negative electrode collector, a separator for separating positive electrode plate and negative electrode plate, and a nonaqueous electrolytic solution containing nonaqueous solvent and electrolytic salt. The separator contains polyolefin as principal material and having a uniform lithium metal film formed on the portion on negative electrode plate side surface which does not face the negative electrode active material layer. The lithium metal film is electrically insulated from positive electrode collector.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of lithium-ion battery.    Lithium-ion battery (10)    Positive electrode plate (11)    Negative electrode plate (12)    Separator (18)    Insulating tape (19)