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3.7V Li-ion Rechargeable Battery

3.7V Li-ion Rechargeable Battery

Regular price $12.30
Regular price Sale price $12.30
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The 3.7V Li-ion Rechargeable Battery is a Heavy Duty capacity 18650 battery for high drain devices. With tremendous capacity and value, the Ultrafire 4000mAh 18650 is a high-powered li-ion battery that is perfect for demanding electronics such as tactical LED flashlights. These batteries feature 3.7 Volts of power and a top-of-the-line 4000mAh capacity that will keep high drain electronics running longer than competing power sources. Combined with reliable manufacturing quality and bulk value pricing, the Ultrafire 18650 is one of the best deals when it comes to li-ion power.


Each Ultrafire 18650 is outfitted with a uniquely designed PCB (printed circuit board) that functions as the brain of the battery, regulating output and intake of electrical charge. Thanks to the circuit board the battery is always safe to use and charge, as it will cut off the battery if the voltage drops below 2.5V or exceeds 4.25V. You can rest assured that your battery will perform perfectly every time since it’s PCB protected!


Battery Terminal Type: Button Top

Capacity: 4000mAh

Composition: Lithium-Ion

Nominal Voltage: 3.7V

Cut-off Voltage: 2.5B

Internal Impedance: ≤ 180 Milli-Ohms

Cycle Performance: 90% of initial capacity at 400 cycles

Type: 18650 Li-ion Rechargeable Battery

Charge Cycles: 500

Color: RED

Dimensions: 66.0 mm x 18.0 mm

Weight: 26.5g

Battery Shelf Life: 3 Years

Brand: UitraFire

Compatible with: Battery appliances such as Emergency Lighting, Flashlights, Portable Devices, Power Tools.


    • 18650 Lithium ion Cylindrical Rechargeable Battery
    • Internal PCB protection prevents under-voltage (2.5V) or over-voltage (4.25V)
    • Higher energy density than competing rechargeable batteries
    • International Electrotechnical Commission (IEC) standard tested to ensure capacity, quality, and lifespan
    • Great for LED flashlights and high drain devices
    • Environmentally friendly
    • 100% Brand New


    UltraFire 18650 4000mAh 3.7V Li-ion Rechargeable Single Battery

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