ARB-L18-3500U Built-in USB Rechargeable Battery

(185 customer reviews)

$33.00 $22.95

SKU: ARB-L18-3500U Categories: , ,

ARB-L18-3500U is a high capacity 18650 Li-ion USB rechargeable battery with a built-in micro-USB charging port.  It also includes a protection circuit in the anode to help prevent short circuits, over charge/discharge and over heating. These USB rechargeable batteries can quickly be charged without the need for a separate charger.  This not only save you money from purchasing a charger, but also convenience of not having to carry around another device.  This will work in all of the current models that utilize a li-ion 18650 battery, including best sellers like the PD35 V2.0, PD35TAC, TK20R, TK75, TK15UE, and more. A micro-USB charging cord is NOT included. Click here to see other models that utilize 18650 batteries:

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  • Micro-USB charging port
  • 3500mAh high capacity
  • USB rechargeable batteries
  • Protection circuitry to prevent short circuits
  • Pressure vents to prevent explosions
  • 500 charge cycles
  • Voltage: 3.6V
  • Charging Current: Recommended 1A, maximum 2A
  • Charging Current USB Port: 0.8A
  • Weight: 1.8 ounces (50.2g)
  • Size: Length: 2.8″ (70mm) Diameter: 0.7″ (18.6mm)
  • Warranty Period: 12 month from date of purchase
  • Indicator light on battery is red while charging, blue when charged

185 reviews for ARB-L18-3500U Built-in USB Rechargeable Battery

  1. Bill Burke (verified owner)

    The batteries seem to be good and they’re easy to charge with the usb port. The only complaint I have is, I don’t know when they are charging or done charging because the indicator light does not show on either of batteries. I have to get my electric meter out to see if / when they are fully charged. If I’m not home when they need charging, it’s a guessing game as to when they are fully charged!

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    • Dianne (store manager)

      I’ve asked warranty to contact you about that – they should have a light that indicates when charged.

  2. John V. (verified owner)

    I appreciate the light indicator on the top of the recharger battery, but I wish the indicator would flash or blink when close to full charge instead of the solid red light when plugged in. I.e less than fifty 1 blink a second, seventy five percent charge 2 blinks… etc. I know I’m asking for a smarter battery which would be hard to program and install in such a small device, but I wouldn’t mind spending the extra money for a simple feature like that.

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  3. Anonymous (verified owner)

    I have charged these batteries without a problem but, honestly, I’m still using the 2600mAh that I’ve been using for a few years now so I really cannot review this battery yet. I use my Fenix UC35 on the lower brightness settings maybe 80% of the time, so the batteries LAST quite a while. I do expect the 3500mAh to last a ridiculously long time.

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  4. Dick Hines (verified owner)

    Time will tell if the charging port is durable. So far I have no complaint.

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