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Fenix ARB-L18-3500U USB Rechargeable Li-ion 18650 Battery

Fenix ARB-L18-3500U USB Rechargeable Li-ion 18650 Battery

Regular price $24.95 USD
Regular price $0.00 USD Sale price $24.95 USD
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The Fenix ARB‑L18‑3500 is a high-capacity 18650 rechargeable Li‑ion battery, offering 3,500 mAh within a standard size that fits most high-performance flashlights. Built for safety and durability, it includes a button-top design, integrated protection circuitry against overcharge, over-discharge, short-circuit, and overheating, plus pressure relief vents to prevent buildup and reduce risk of swelling or rupture. A robust steel-infused anode structure further improves impact resistance and electrical safety. This cell is rated for up to 500 charge cycles, maintaining around 75% capacity afterward, and carries Fenix’s 12-month warranty.

Key Specifications:

  • Capacity & Voltage: 3,500 mAh, 3.6 V
  • Protection Features: Overcharge, over-discharge, short-circuit, overheat protection; pressure relief vents; reinforced steel anode
  • Design: Button-top, compatible with Fenix and other 18650 devices
  • Durability: Up to 500 charge cycles, retains ~75% capacity over time
  • Size & Weight: Approx. 69 mm length × 18.6 mm diameter; ~50 g
  • Warranty: 12-month manufacturer’s warranty

A reliable, long-lasting, and safe power solution—perfect for tactical flashlights, headlamps, lanterns, and high-drain devices.

Note: This item is packaged and priced as one battery. 

Shipping Note: Lithium ion batteries are considered "dangerous goods" per US transportation regulations and can often only be transported via ground shipment. Orders containing loose batteries will typically take much longer than predicted to be delivered. Delivery times of 14+ days are not uncommon.  

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