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Samsung 21700 Lithium Rechargeable Cell: 3.6V 5000mAh (18Wh, INR21700-50E) - UN38.3 Passed -

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Battery SamSung 21700 INR21700-50E Cylindrical Li-Ion Cell
Standard Capacity Min: 4900mAh
-Charge: 0.5C(2450mA), 4.2V, 0.02C(98mA) cut off @ RT
-Discharge: 0.2C(980mA), 2.5V cutoff @ RT
Rated Capacity Min: 4753mAh
-Charge: 0.5C(2450mA), 4.2V, 0.02C(98mA) cut off @ RT
-Discharge: 1C(4900mA), 2.5V cutoff @ RT
Charging Voltage 4.2V
Nominal Voltage 3.6V
Charging Method CC-CV   (0.02C/98mA cut-off)
Charge Current
  • Standard charge: 2450mA, charge time: 3 hours
  • Max. charge: 4900mA (not for cycle life)
Max. Discharge Current 2C/9800mA (for continous discharge)
3C/14700mA (not for continous discharge)
Discharge Cut-off Voltage 2.5V
Cycle Life Capacity ≥ 3,802mAh @ after 500cycles
(80% of the Rated Discharge Capacity @ RT)
- Charge : 0.5C(2,450mA), 4.2V, CCCV 0.05C(245mA) cut-off @ RT
- Discharge: 1C(4,900mA), 2.5V cut-off @ RT
Cell Weight 69g max (2.45oz)
Cell Dimension
  • Height: 70.80mm (2.79" Max)
  • Diameter: 21.15mm (0.83" Max)
Operating Temperature (surface temperature)
  • Charge : 0 ~ 45℃
  • Discharge: -20 ~ 60℃
Discharge OTP(over temp. protection) should not be over 60°C of the cell surface temperature. Protection set should be based on the location of the cell
surface with the highest temp increase part of the battery pack
Storage temperature
  • 1 year: -20 ~ 23℃
  • 3 months: -20 ~ 45℃
  • 1 month: -20 ~ 60℃
Note: If the cell is kept as ex-factory status (30% of charge), the capacity recovery rate is more than 80% of stuandard discharge capacity.

Please download the Specification here


  • Li-Ion Batteries may explode if charged or discharged improperly.
  • Please possess knowledge of electronic and understand how to handle Li-ion battery. 
  • Please always use a protection circuit board (PCB) to keep battery from overcharged and over-discharged
  • Never solder directly onto the Li-ion battery as overheat might damage the battery. If you are making a pack or need to solder batteries together, you need to get battery with tabs on it. You will solder to tabs instead directly onto the battery.
  • Please read more safety warning about Li-ion battery
  • California residents: Warning: Cancer and Reproductive Harm - See Prop 65 Warnings

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