FENIX 21700 5000 mAh s USB-C (Li-Ion) - rechargeable batteries

Fenix 21700 5000 mAh rechargeable battery (ARB-L21-5000U) with its own USB-C charging connector. It can be charged by connecting a cable to the USB-C connector (e.g. from a computer, power bank or mobile phone charger) or in a conventional Li-ion charger. The Fenix 21700 5000 mAh rechargeable batteries with protected electronics are based on the cutting-edge LiNiCoO2 technology, which brings both higher safety and longer life.

Li-ion rechargeable batteries feature very high capacity, do not suffer from memory effect or self-discharge. Li-ion in the 21700 size are the best choice in terms of stored energy due to the size and weight of the battery, and are gradually gaining ground, for example in the automotive industry.

Fenix battery protection consists of internal safety mechanisms and protective electronics. Added electronic circuits prevent the cell from overcharging, over-discharging and against short-circuiting or excessive current draw. If the battery electronics assess that the limits have been reached, they safely disconnect the cell.

Internal protection consists of a separator, state-of-the-art Positive Temperature Coefficient (PTC) overheat protection and a special anti-blast valve. In the event that the gas pressure in the cell exceeds a certain limit, the internal separator separates the electrodes inside the battery and thus de-facto interrupts the exothermic reaction and the anti-blast valve releases the excess gas pressure outside the battery. The combination of electronic and mechanical (temperature and pressure) protection makes Fenix batteries among the safest Li-ion batteries available.

This battery is designed to operate in the Fenix HT18, PD36R, TK22 V2.0, TK22 UE, E35 V3.0 LED flashlight, for example. However, it cannot be used in 18650 battery flashlights due to its larger size!

Due to the 76 millimeters length of the battery (including the protective electronics), it can only be charged in chargers that are adapted to this length. See recommended chargers below.

Fenix 21700 5000mAh USB Battery Specifications

• Nominal voltage : 3.6V
• Capacity : 5000 mAh, tested at 0.2 C discharge current with termination at 2.5 V and 25°C
• Maximum current draw : 8 A
• Maximum charging current: 5 A
• Built-in USB-C connector charging current 2A. Charging time approximately 3-4 hours.
• Dimensions: 21.5mm (diameter) x 76mm (length) (+/- 0.5mm)
• Weight 72.5 grams
• Overcharge, full discharge and short circuit protection (>8 A). Protective circuit mounted on the plus pole.
• Lifetime of more than 500 charge cycles
• Recommended operating temperatures: 0-45°C (charging), -20 to +60°C (discharging)
• Scope of delivery: one piece of Fenix 21700 5000mAh USB battery (ARB-L21-5000U)
• Charging cable not included. If needed, a basic USB-C cable or a colored USB-C cable can be purchased, or a micro-USB to USB-C reducer can be used.

Charging via USB-C connector
Plug the USB cable into the side USB-C connector, the indicator light in the plus pole of the battery glows red during charging. When full charge is reached, it glows blue.

Recommended chargers

The battery can also be charged in chargers for Li-ion batteries type 21700:

Fenix ARE-A2 charger
Fenix ARE-D1 USB charger
Fenix ARE-D2 USB charger
Fenix ARE-A4 charger
Sc1 USB charger

Caution
Do not discharge the battery below 2,5V
Do not short-circuit the battery (do not connect the cell poles with a wire)
Do not throw the battery into fire or water
Do not insert the battery into the charger in reverse (opposite polarities)
When using the battery, observe safety guidelines
Use only an adequate charger that supports Li-ion batteries