A method of charging a secondary battery, wherein the secondary battery is a lithium ion battery having embedded therein an electrode assembly including a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode in a battery case in a state of being impregnated with an electrolytic solution, wherein the negative electrode comprises graphite carbon as a negative electrode active material, wherein there are charging sections defined at least by preset charging C-rates, and constant current-constant voltage, CC-CV, charging is performed in each of the charging sections, wherein the charging sections comprise: a first charging section in which a CC-charging is performed during which a first preset charging C-rate is supplied until the voltage of the secondary battery reaches a first charging cutoff voltage, and a CV-charging is performed during which the charging C-rate gradually decreases after having reached the first charging cutoff voltage; a second charging section, after the first charging section, in which a CC-charging is performed during which a second preset charging C-rate is supplied until the voltage of the secondary battery reaches a second charging cutoff voltage, and a CV-charging is performed during which the charging C-rate gradually decreases after having reached the second charging cutoff voltage; and a third charging section, after the second charging section, in which a CC-charging is performed during which a third preset charging C-rate is supplied until the voltage of the secondary battery reaches a third charging cutoff voltage, and a CV-charging is performed during which the charging C-rate gradually decreases after having reached the third charging cutoff voltage, wherein the charging cutoff voltage satisfies the conditions V1 = n - (0.25V∼0.15V), V2 = n - (0.2V∼0.1V), and V3 = n; with n being an electric potential in volts at the full charge of the secondary battery, and V1, V2, and V3 being the first, second and third charging cutoff voltages, respectively, wherein V1<V2<V3, characterized in that the ratio of the first preset charging C-rate: the second preset charging C-rate: the third preset charging C-rate satisfies the following condition: C1: C2: C3 = 3.8∼4.2: 2.8∼3.2: 0.8∼1.2. a first charging section in which a CC-charging is performed during which a first preset charging C-rate is supplied until the voltage of the secondary battery reaches a first charging cutoff voltage, and a CV-charging is performed during which the charging C-rate gradually decreases after having reached the first charging cutoff voltage; a second charging section, after the first charging section, in which a CC-charging is performed during which a second preset charging C-rate is supplied until the voltage of the secondary battery reaches a second charging cutoff voltage, and a CV-charging is performed during which the charging C-rate gradually decreases after having reached the second charging cutoff voltage; and a third charging section, after the second charging section, in which a CC-charging is performed during which a third preset charging C-rate is supplied until the voltage of the secondary battery reaches a third charging cutoff voltage, and a CV-charging is performed during which the charging C-rate gradually decreases after having reached the third charging cutoff voltage, wherein the charging cutoff voltage satisfies the conditions V1 = n - (0.25V∼0.15V), V2 = n - (0.2V∼0.1V), and V3 = n; with n being an electric potential in volts at the full charge of the secondary battery, and V1, V2, and V3 being the first, second and third charging cutoff voltages, respectively, wherein V1<V2<V3, characterized in that the ratio of the first preset charging C-rate: the second preset charging C-rate: the third preset charging C-rate satisfies the following condition: C1: C2: C3 = 3.8∼4.2: 2.8∼3.2: 0.8∼1.2.