Battery: Li-ion 18650 2400mAh 3.7V 18650 Rechargeable Li-ion Battery Product Details: Battery Type: Li-ion 18650 Nominal Voltage: 3.7V Nheight:65.4 mmresistance: 20 mΩrecommended charge current: 3Cconstant discharge current: 10Cweight: 40 g