3.7V 1200mAh 18650 Lithium Rechargeable Cell Hongli

The 3.7V 1200mAh 18650 Lithium Rechargeable Cell from Hongli is a cylindrical Li-Ion cell in the 18650 format 18mm diameter and 67mm length, the most widely used rechargeable cell size in DIY electronics, torch, and custom battery pack construction. The 18650 name comes directly from those dimensions. At 3.7V nominal and 1200mAh capacity, this cell stores 4.44Wh of energy enough to run a 100mA Arduino-based project for approximately 12 hours from a single cell.

The 1200 mah rechargeable battery rated 300 cycle life means the cell maintains usable capacity for at least 300 full charge and discharge cycles under standard conditions before dropping significantly below its rated 1200mAh. Hongli cell internal impedance below 1 ohm keeps voltage sag low under moderate current loads high internal impedance causes the terminal voltage to drop more under load, reducing the effective energy available to the circuit even when the cell still holds charge. The overcharge voltage of 4.18V is slightly conservative compared to the 4.2V limit on standard Li-Ion cells, which provides an additional margin of protection for cell chemistry and cycle life.

The 18650 lithium cell for projects is a single cell at 3.7V for requiring higher voltage, multiple cells connect in series. Two cells in series produce 7.4V, three produce 11.1V. Each cell in a series pack needs a matching charger with balance charging to maintain equal cell voltages across cycles. The 3.7 volt rechargeable battery suits torch and flashlight, power bank DIY, and custom multi-cell battery pack construction. This rechargeable cell is working on portable power and Li-Ion battery pack. Available on StemVolt.

Related Product:

• Checkout 3.7V 2000mAh 18650 Li-Ion Rechargeable Battery Cell Hongli

Features:

• 18650 cylindrical format fits standard 18650 cell holders and battery pack slots
• 300 rated cycles before capacity drops significantly below 1200mAh specification
• 4.18V overcharge limit adds protective margin beyond standard 4.2V Li-Ion ceiling
• Under 1 ohm impedance reduces terminal voltage sag at moderate current draws
• Hongli branded cell with consistent dimensional compliance at 67 x 18 mm

Technical Specifications:

Applications:

• 3.7V 1200mAh 18650 lithium rechargeable cell powers single-cell DIY flashlight and torch
• Rechargeable 18650 batteries custom 2S or 3S Li-Ion packs for robot chassis
• 18650 lithium ion battery powers portable ESP32 IoT sensor node in remote field deployments
• Battery fits DIY power bank with TP4056 charging module and boost converter
• Hongli cell custom 3S battery pack for portable Arduino-based instrument project

Package Includes:

• 1 × 3.7V 1200mAh 18650 Lithium Rechargeable Cell Hongli