This part is a kind of semiconductor called CGR17670HC.

Function of this product has LITHIUM ION BATTERIES.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

LITHIUM ION BATTERIES (INDIVIDUAL DATA SHEETS) CGR17670HC:CylindricalModel Discharge Characteristics Specifications Nominal Voltage Standard Capacity *1 Dimensions *2 Diameter Height Weight 3.7 V 1250mAh 17.0 mm 66.7 ± 0.3 mm Approx. 35 g * 1 After a fresh battery has been charged at constant voltage/constant current (4.2 V, 840 mA (max), 2 hours, 20°C), this is the average of the capacity (ending voltage of 3 V at 20°C) that is discharged at a standard current (240 mA). *2 Dimensions of a fresh battery LITHIUM ION BATTERIES (INDIVIDUAL DATA SHEETS) CGR17670HC Discharge Characteristics Storage Characteristics Charge Characteristics Cycle Life Characteristics [ ... ]

CGR17670HC PDF Datasheet Download