Premium rechargeable Fenix 18650 4000 mAh batteries with integrated USB-C connector (ARB-L18-4000U) and protected electronics deliver the highest real capacity on the market. Li-ion rechargeable batteries are characterised by very high capacity, suffer no memory effect and have minimal self-discharge. Li-ion in 18650 size is the best choice in terms of stored energy relative to battery dimensions and weight.

The battery can be charged by connecting a cable to the integrated USB-C connector (for example from a computer or mobile phone charger), or in a torch fitted with a USB connector or in a charger that accommodates Li-ion batteries up to 72 millimetres in length.

Note that this battery, due to the added USB-C charging connector, is approximately 72 millimetres long, making it significantly longer than standard Li-ion 18650 type. It will therefore fit only in some torches, head torches and chargers. We have verified compatibility with the following Fenix torches and head torches: Fenix PD32R, Fenix PD35 V3.0, Fenix E28R V2.0, Fenix LD30R, Fenix TK11 TAC, TK11R, TK26R, Fenix TK35 UE V2.0 (5000 lumens), Fenix CL26R, Fenix CL30R, Fenix HM62-T, HM65R-T V2.0, HM75R, Fenix HM61R, Fenix HM61R V2.0.

Fenix battery protection consists of internal safety mechanisms and protective electronics. Added electronic circuits prevent overcharging, excessive discharge and short circuits, as well as excessively high current draw. If the battery electronics detect that limit values have been reached, they safely disconnect the cell.

Internal protection consists of a separator, overheat protection (PTC thermal protection) and a special anti-explosion vent. If the gas pressure inside the cell exceeds a certain threshold, the internal separator isolates the electrodes within the battery, effectively interrupting the exothermic reaction, and the anti-explosion vent releases excess gas pressure from the battery. Thanks to the combination of electronic and mechanical (thermal and pressure) protection, Fenix batteries rank among the safest available Li-ion batteries.

Specifications for Fenix 18650 4000 mAh USB-C battery

• Nominal voltage: 3.6 V
• Capacity: 4000 mAh
• Maximum current draw: 7 A
• Maximum charging current: 4 A
• Dimensions: 18.75 mm (diameter) x 72 mm (length) (+/- 0.5 mm)
• Weight: 50 grams
• Protection against overcharging, complete discharge and short circuit (>7 A). Protective circuit attached to the positive pole.
• Lifespan of more than 500 charging cycles
• Recommended operating temperatures: 0–45 °C (charging), −20 to +60 °C (discharging)
• Contents: one Fenix 18650 4000 mAh battery (ARB-L18-4000U).

Charging via USB-C connector

Connect a USB cable to the side USB-C connector; during charging, the indicator light on the top of the battery glows red. Once fully charged, it glows blue. When using a USB source with a current of 1500 mA or higher, charging time is approximately 2.5 hours.

Recommended chargers

Fenix ARE-A2 charger
Fenix ARE-A4 charger
Fenix ARE-D1 USB charger
Fenix ARE-D2 USB charger
FC2 dual-channel USB charger
SC1 USB charger
VC8 eight-channel USB charger
SkyRC MC3000

Warning

• The battery is approximately 72 mm long; check first that it will fit in your device.
• If possible, do not discharge the battery below 2.5 V.
• Do not short-circuit the battery (do not connect the cell terminals with a conductor).
• Do not throw the battery into fire or water.
• Never insert the battery into a charger in reverse (with opposite polarity).
• When using the battery, observe safety guidelines.
• Use only an appropriate charger that supports Li-ion batteries.

Warranty

Two-year warranty.

• Capacity: 4000 mAh
• Weight: 50 g

We offer a 30-day period for returning or exchanging goods if, for any reason, you are not satisfied with your order.

For more information, please see our Return Policy here.

Orders received by 14:00 are dispatched the same day. Delivery usually takes place on the next business day, depending on the selected shipping method. During busy periods, please allow 1–3 business days for order processing.

Free delivery from €200 / for oversized shipments from €400

Free of charge, ready for pickup on the next business day

For more information, please see our Delivery page.