18650 li-ion battery pack 3.7v.

RYDBATT Lithium ion 18650 cylindrical rechargeable battery, 3.7V 2,000mAh high capacity, for laptop batteries and portable power devices

Features: 
* Lithium ion 18650 cylindrical rechargeable battery
*3.7V 2200mAh high capacity
* Higher energy density and lower weight than other types of rechargeable
batteries
*Manufactured under ISO9001 to assure quality
* Internal PCB protects against under and over charging - low voltage 2.8V, high
voltage 4.2V
*Battery tested based on International Electrotechnical Commission (IEC) standard
to ensure capacity, quality and life time

Applications:
* Built-in laptop batteries
*Built-in portable power devices needing high energy density and low weight

Cautions:
* Use special caution when working with Li-ion cells, they are very sensitive to
charging characteristics and may explode if mishandled 
* Make sure user has enough knowledge on Li-ion rechargeable batteries in
charging, discharging and assembly before use
*We are not responsible for any damage caused by misuse or mishandling of
these Li-ion batteries

Specifications:
Capacity:
a) *Nominal: 2200mAh
b) *Min.: 2150mAh
*Dimensions:
a) *Diameter: 18+/-0.2mm
b) *Height: 68+/-0.2mm
*Weight (typical): approx. 46g 
* Nominal voltage: average 3.7V 
* Cut-off voltage: 3.0V
*Internal impedance: less or equal to 180 milliohm (with PTC) 
* Cycle performance: 90% of initial capacity at 400 cycles 
* Cycle life: > 500 cycles
* Charge: current = 0.5C mA, voltage = 4.2V, end current = 0.01mA 
* Discharge: current = 0.5C mA, end voltage = 3.0V
*Max. charging current: 1.5C mA
* Max. discharging current 1.5C mA (for continuous discharge)