Battery Specifications:

• Capacity (Ah): 3.4 Ah ( 3400mAh)
• Charging Voltage (V): 4.2 V
• Energy (Wh): 12.2 Wh
• Energy Density (Wh/L): 730 Wh/L
• Nominal Voltage (V): 3.6V-3.7V
• Weight (g): 46 g
• Diameter (mm): 18.06 mm (+/- 0.03 mm)
• Height (mm): 65 mm (+/- 0.03 mm)
• Max. Discharge rate: C Rating 2C (Maximum recommended current 6.8A)
• Top (positive side): Flat top
• Model: NCR18650B
• Made in Japan
• Made by Panasonic 

NCR18650B Datasheet Specifications Panasonic

Important:

• Never completely discharge li-ion battery ( below 2.5V under load ).
  
• Charge fully to 4.2V before first use.
• Never use force to install (insert) li-ion battery.
• Do not use old and new battery cells together. 
• Use only high-quality battery charger.
• Do not expose to heat. 
• Do not short (connect) positive (top), and negative (bottom) battery terminals (contacts). Keep battery that is not in use in a plastic holder (or any insulating [plastic] container).
• Never charge the battery over 4.25V (another reason to use high-quality battery charger).
• Do not charge unattended.
• Do not use old, and new cells together.
• Do not store your li-ion batteries fully charged (for an extended period of time).
• Store in cold and dry place at approximately 3.7V (storage charge).
• After the battery is discharged-don't leave it discharged=>charge it as soon as possible.