Rechargeable Li-ion Battery 18650 3.7v

Rechargeable 18650 Li-ion Battery (3.7V) is a high-energy cylindrical lithium cell widely used in portable electronics and DIY power projects. The standard 18650 size makes it ideal for building battery packs, power banks, flashlights, and rechargeable systems. It delivers stable voltage and can be recharged many times when used with a proper Li-ion charger and protection circuit.

Key Features

• Battery Type: Rechargeable Lithium-ion (Li-ion)

• Nominal Voltage: 3.7V (4.2V when fully charged)

• Standard Size: 18650 (widely compatible)

• High energy density for long runtime

• Suitable for single-cell use or series/parallel battery packs

• Ideal for DIY projects, portable devices, and backup power

Full Specifications (General / Typical)

Exact values (capacity, discharge rate, protected/unprotected) depend on the battery model.

Electrical

• Nominal Voltage: 3.7V

• Charge Voltage: 4.2V (Li-ion standard)

• Battery Chemistry: Li-ion

• Rechargeable Cycles: designed for repeated charging (proper use extends life)

Mechanical

• Form Factor: 18650 cylindrical cell

• Type: Flat-top or Button-top (varies by model)

• Protection: Protected or Unprotected (varies by model)

Applications

• Power banks (with 18650 power bank/boost module)

• Flashlights and portable LED lighting

• Robotics and DIY electronics

• IoT portable power (ESP32/Arduino with regulator)

• Battery pack building with BMS (for 2S/3S/4S packs)

• Backup power and small UPS projects

Used In

• Rechargeable device projects and maker kits

• Solar storage mini systems (with proper charge controller)

• Portable test equipment and sensors

Package Includes

• 1× Rechargeable 18650 Li-ion Battery 3.7V

Safety / Usage Notes (Good for product pages)

• Use a Li-ion charger (4.2V charging profile)

• Do not short-circuit, puncture, crush, or expose to heat/fire

• For battery packs, always use a BMS/protection board

• Store in a cool, dry place and avoid deep discharge