18650 li-ion battery 1).factory price, fast delivery 2) Stable,safe and ... consistency 4) Long life cycle 3.7v 2200mAh Lithium Battery packsingle 18650 battery capaciy have:1800mah 2000mah 2200mah 2600mah 3000mahAdvantages:1, High ... energy density2, High working voltage for single battery cells pollution-free ...