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21700 Lithium Rechargeable Cell: 3.65V 4000mAh (14.6Wh) - UN38.3 Passed

With Tabs
Your Price: From $8.90 to $11.90

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  • Lithium 21700
  • Nominal Voltage: 3.65V @0.2C
  • Charge Voltage: 4.2V±0.03V
  • Discharge Cut off Voltage: 2.75V
Capacity (0.2C Discharge)
  • Nominal Capacity: 4000 mAh
  • Minimum Capacity: 3900mAh
Standard Charge (25°C±2°C)
  • CC/CV
    • Current: 0.5C (2000mA)
    • Voltage: 4.20V
    • End of current: 80mA±5mA
Max. Charge Current
  • 0°C ≤ T ≤ 5°C,   0.1C (400mA)
  • 5°C < T ≤ 15°C, 0.2C (800mA)
  • 15°C<T ≤ 45°C, 0.5C (2000mA)
Standard Discharge
  • CC
  • Current: 0.5C (2000mA)
  • End of Voltage: 2.75V
Max. Continuous Discharge Current
  • -20°C ≤ T ≤  5°C, 1C (4000mA)
  •    5°C < T ≤ 45°C, 3C (12000mA)
  •   45°C <T ≤ 60°C, 1.5C(6000mA)
Cycle Life (25°C±2°C, 0.5C Charge/1C Discharge)
  • ≥ 80% Capacity after 1000 cycles
Temperature Charge: 0 to +45ºC
Discharge: -20 to +60ºC
  • 1 month: -20 to + 60ºC
  • 3 month: -20 to + 40ºC
  • 12 month: -20 to + 20ºC
Dimension (DxH) 21.7±0.2mm,  70.9±0.2mm
Weight 69±2g (2.7oz)

Please download the Specification here


  • Li-Ion Batteries may explode if charged or discharged improperly.
  • Please possess knowledge of electronic and understand hot to handle Li-ion battery.
  • We reserve the right not to sell and void the warranty it you don't meet the above statement.
  • Please use a protection IC (PCB) to keep battery from overcharge and over discharge
  • Never solder directly onto the Li-ion battery as overheat might cause battery to explode. 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

Related Products

  • For DIY, please add tabs as an option at a little extra cost
  • Our battery packs build by 21700 cells.
  • Need to DIY?  Please install our PCB or your own PCB withthe following features:
    • 4.2V/cell over-charge protection
    • 2.5V/cell over-discharge protection
    • Max currentover-drain protection
    • Shortcircuit protection.
  • Batteryspace.com is NOT liable for any misuse due to any other brand of PCB applied
  • If you don't know how to make Li-Ion pack, please don't DIY, click here to choose a pre-wired Li-Ion pack module from 3.7V-37V

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We own a national standard UN38.3 testing lab. We can provide UN38.3 test service to our customer.

If you want to set up your own lab, we also provide UN38.3 & IEC62133 equipments and onsite training. Email us for the quote and lead time.
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