Fenix ARB-L21-5000U battery on white background
Fenix ARB-L21-5000U battery being recharged via built-in usb-C charging
Fenix ARB-L21-5000U battery transparent image showing multiple layers of protection
Fenix ARB-L21-5000U battery pressure relief vents
Fenix ARB-L21-5000U battery specifications chart
Fenix ARB-L21-5000U battery on white background from the side
Fenix ARB-L21-5000U battery on white background showing charging port

Fenix 21700 Rechargeable Battery - 5000U

Regular price$25.95
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This 21700 battery from Fenix is designed to handle the additional power and capacity for high lumen flashlights giving them longer run times. What makes this 21700 battery even better is the USB Type-C charging port that is embedded in the cell. You don't have to use a separate charger to charge the battery; it can all be done with a wall adapter and USB Type-C charging cord. It is likely that you already have these in your home since many cellphones use this same type of charging port.

Shipping Note: Lithium ion batteries cannot be shipped via expedited shipping service due to shipping carrier restrictions. Orders that include lithium ion batteries that aren't included in lights they are meant to power will be shipped via UPS or USPS ground service. 

  • 5000mAh Capacity
  • USB Type-C Charging
  • 500 Charging Cycles
  • Protection Circuits in Anode
  • Overcharge Protection
  • Over-discharge protection
  • Short Circuit Protection
  • Overheat protection
  • 3 sets of overheat protection
  • Pressure relief valve
  • Microporous PTC Cathodal Block
  • 3.6V USB Charging - USB-A to USB-C Cable
  • Single Port Charger
  • 1 Amp/2 Amp at 10 Watts Max
  • Maximum Output Current 8A
  • Weight: 2.56 oz / 72.5g
  • 2.99" Height
  • 0.85" Diameter
  • **USB Cable NOT Included**
  • One Fenix ARB-L21-5000U USB-C Rechargeable 21700 battery