Fenix ARB-L18-3500U
(6 reviews)
A premium 18650 battery that recharges directly via a built-in micro-USB port, with no external charger: 3500 mAh, an LED indicator and multiple protections.
Characteristics
- Capacity / Voltage: 3500 mAh / 3.6V
- Rechargeable: Yes, via built-in micro-USB (Lithium)
- Pack size: Sold individually
- Direct USB charging, LED indicator, multiple protections
Detailed overview: Fenix ARB-L18-3500U 18650 USB-rechargeable battery
Fenix, famous for its ultra-powerful, top-quality torches, offers here an innovative, excellently built 18650 battery. Its major asset: it has a built-in micro-USB port, which lets you recharge it anywhere, using any device with a USB socket (computer, phone charger, power bank...), with no need for a dedicated cell charger.
Powerful, it has a capacity of 3500 mAh, making it the ideal battery for demanding devices such as torches, for which it was designed. Rated for about 500 charge cycles, fitted with an LED charge-level indicator, it includes multiple protections (against short circuits, overheating, overcharge and deep discharge). All of this makes it one of the most reliable and best-protected 18650 cells on the market.
Note that this on-board electronics comes at the cost of the battery's total length, which reaches 70 mm (for 18.6 mm diameter), slightly more than a standard 18650. Before buying, check that your torch or device accepts a button-top cell slightly longer than the 18650 standard.
EAN: 6942870304724
Frequently asked questions: Fenix ARB-L18-3500U 18650 USB-rechargeable battery
Directly via its built-in micro-USB port, with any cable and USB source (computer, phone charger, power bank). No external cell charger is needed, and an LED indicator shows the charge level.
Not necessarily. Its charging and protection electronics extend it to 70 mm, slightly more than a standard 18650. Before buying, check that your torch or device accepts a button-top cell that is a little longer.
3500 mAh at 3.6V, a high capacity for this format. It is built for demanding devices such as powerful torches, where it offers plenty of runtime.
Yes, that is one of its strengths. It includes protections against short circuits, overcharge, overheating and deep discharge, and handles about 500 charge cycles, making it a particularly safe 18650.
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Published on 08/07/2026, updated on 14/08/2026