Rechargeable 21700 Li-ion Battery Nitecore 21700 5500mAh 20A 3.6V

The Rechargeable 21700 Li-ion Battery Nitecore 21700 5500mAh 20A 3.6V is a high‑capacity cylindrical cell designed for devices that accept 21700 format batteries. With a nominal voltage of 3.6V and a rated capacity of 5500mAh, this cell provides extended runtime for portable electronics. The battery supports continuous discharge currents up to 20A, making it suitable for moderate‑drain applications where a balance of capacity and current delivery is required.

Advantages

This Nitecore 21700 battery offers a large energy reserve combined with stable nominal voltage and reliable continuous discharge capability. The cell construction emphasizes capacity retention and safe operation when used within specified current and charging limits. Its 21700 form factor provides higher energy density compared with smaller cylindrical cells, allowing longer run times in compatible devices.

Suitable for

• High‑capacity flashlights and headlamps that accept 21700 cells
• Power banks and portable chargers using 21700 cells
• Portable electronics and devices requiring extended runtime
• Moderate‑current tools and equipment with a 20A continuous draw limit

Key specifications

• Cell type: Rechargeable Li‑ion cylindrical 21700
• Nominal voltage: 3.6 V
• Rated capacity: 5500 mAh
• Maximum continuous discharge current: 20 A
• Form factor: 21700 (standard cylindrical profile)

How to use

Install the cell in devices that explicitly specify compatibility with 21700 Li‑ion batteries and observe polarity markings. Charge only with chargers designed for rechargeable lithium‑ion cells and follow the charger manufacturer’s instructions. Avoid charging or discharging above the specified current limits and do not use damaged or swollen cells. Store batteries at moderate temperatures and partial state of charge if long‑term storage is required.

Usage recommendations

Follow manufacturer guidelines for charging rates and safe handling. Use a compatible charger with proper cell termination and protection, monitor the cell for signs of damage, and avoid exposing the battery to extreme heat, mechanical damage, or water. Replace cells that show physical deformation or significant capacity loss.