SureFire SF18650B Rechargeable Battery 3500mAh 3.6V Li-Ion Single

The SureFire SF18650B delivers consistent power output for tactical flashlights and weapon lights in demanding environments. This rechargeable lithium-ion battery provides 3,500 mAh capacity at 3.6 volts, ensuring extended runtime for critical operations.

What Makes This Different

Built specifically for high-drain tactical applications, the SF18650B features protected circuitry that prevents over-discharge and thermal runaway. Unlike standard consumer batteries, this cell maintains stable voltage output under heavy loads and extreme temperatures. The proprietary chemistry delivers up to 300 charge cycles while retaining 80% capacity.

Key Features

• 3,500 mAh capacity provides extended runtime for weapon lights and tactical flashlights
• Protected circuit board prevents over-discharge, overcharge, and short circuit conditions
• Flat-top design ensures reliable contact in SureFire and compatible devices
• Operating temperature range from -20°F to 140°F maintains performance in harsh conditions
• Low self-discharge rate retains 85% charge after 12 months of storage
• Button-top positive terminal fits most 18650-compatible tactical lights
• Red and black color coding prevents confusion with standard alkaline cells

Field testing demonstrates consistent performance across temperature extremes and high-drain applications. Law enforcement and military units rely on this battery for weapon-mounted lights during extended operations. The protected circuitry eliminates the risk of catastrophic failure that can occur with unprotected lithium cells under stress.

Technical Specs

• Capacity: 3,500 mAh
• Voltage: 3.6V nominal (4.2V fully charged)
• Chemistry: Lithium-ion with protection circuit
• Dimensions: 18.6mm diameter x 69.8mm length
• Weight: 48 grams
• Charge cycles: 300+ cycles to 80% capacity
• Operating temperature: -20°F to 140°F (-29°C to 60°C)
• Compatible with SureFire Scout Light, X300, X400 series and other 18650 devices

Professional users choose the SF18650B for mission-critical applications where battery failure creates tactical disadvantages. The combination of high capacity, protection circuitry, and temperature stability makes this the standard for serious applications.