Premium rechargeable batteries Fenix 21700 5000 mAh (ARB-L21-5000) with protective electronics (protected) are based on advanced LiNiCoO2 technology, which delivers higher safety and longer lifespan. Li-ion rechargeable batteries are characterised by very high capacity, do not suffer from memory effect and have no self-discharge. Li-ion in 21700 size are the best choice in terms of stored energy relative to battery dimensions and weight, and are gradually becoming established in, for example, the automotive industry.

Protection of Fenix batteries consists of internal safety mechanisms and protective electronics. Added electronic circuits prevent overcharging of the cell, excessive discharge and also short circuits or 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, the most advanced protection against overheating (PTC - Positive Temperature Coefficient) and a special anti-explosion valve. If the gas pressure in the cell exceeds a certain threshold, the internal separator isolates the electrodes inside the battery and thereby effectively interrupts the exothermic reaction, and the anti-explosion valve releases excess gas pressure from the battery. Thanks to the combination of electronic and mechanical (thermal and pressure) protection, Fenix batteries are among the safest available Li-ion rechargeable batteries.

This battery is designed for use in, for example, the Fenix PD36R LED torch. However, it cannot be used in torches designed for 18650 batteries due to its larger dimensions. Due to the battery length of 76 millimetres (including protective electronics), it can only be charged in chargers that are designed for this length. See recommended chargers below.

Fenix 21700 5000mAh battery specifications

• Nominal voltage: 3.6 V Capacity: 5000 mAh, tested with discharge current of 0.2 C with termination at voltage 2.5 V and temperature 25°C
• Maximum current draw: 7.5 A
• Maximum charging current: 5 A
• Dimensions: 21.5 mm (diameter) x 76 mm (length) (+/- 0.5mm)
• Weight: 72.5 grams
• Protection against overcharging, complete discharge and short circuit (>7.5 A). The protective circuit is attached to the positive pole.
• Lifespan of more than 500 charging cycles
• Recommended operating temperature: 0-45°C (charging), -20 to +60°C (discharge)

Package contents:

• one Fenix 21700 5000mAh rechargeable battery (ARB-L21-5000).

Recommended chargers
Fenix ARE-A2 USB charger Fenix ARE-D1 USB charger Fenix ARE-D2 charger Fenix ARE-A4 USB charger SC2 USB charger SC1

Warning
If possible, do not discharge the battery below 2.5 V Do not short-circuit the battery (do not connect the cell poles 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.

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.

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