This part is a kind of semiconductor called NCR18650BF.

Function of this product has Lithium ion Rechargeable battery.

Manufacturers : Panasonic

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Spec Sheet for NCR18650BF TENTATIVE Dimensions(Typ.) H of D Bare Cell d 65.0mm 18.2mm 9.0 mm Cell Type NCR18650BF Specifications Rated Capacity *at 20deg.C Nominal Capacity *at 25deg.C Nominal Voltage Charging Method Charging Voltage Charging Current Charging Time Ambient Temperature Weight (Max.) Charge Discharge Storage Dimensions (Max.)* Volumetric Energy Density Gravimetric Energy Density (D) (H) Min.3200mAh *at 0.2Cdischarge Min.3250mAh *at 0.2Cdischarge Typ.3350mAh*at 0.2Cdischarge 3.6V Constant Current -Constant Voltage 4.2V Std.1625mA 3.5hrs. 0～+45℃ -20～+60℃ -20～+50℃ 46.5g 18.24mm *without tube 18.50mm *with tube 65.10mm *without tube 65.30mm *with tube 677Wh/l 248Wh/kg Cell Design of NCR18650BF 2 Capacity (Typ.) Charge voltage NCR18650B NCR18650BF [ ... ]

NCR18650BF PDF Datasheet Download