18650 Battery Pack Calculator

Total Voltage
11.1 V
Total Capacity
5000 mAh
Total Energy
55.5 Wh
Total Cells
6 Cells

How to Use Our 18650 Battery Pack Calculator

Welcome to our free 18650 battery pack calculator. This tool is designed to help engineers, hobbyists, and makers easily design custom lithium-ion battery packs. Whether you are building a power bank, an electric bike battery, or an energy storage system, getting the configuration right is critical for safety and efficiency.

Understanding Series (S) and Parallel (P) Configurations

  • Series (S) – Increases Voltage: Connecting cells in series increases the total voltage of your battery pack while keeping the capacity (Ah) the same.

  • Parallel (P) – Increases Capacity: Connecting cells in parallel increases the total capacity and maximum current output while keeping the voltage the same.

Step-by-Step Guide:

  1. Enter the number of Series (S) cells to match your desired voltage.

  2. Input the Parallel (P) configuration to boost your total capacity.

  3. Check the automatically generated total energy in Watt-hours (Wh) and total cells required.

Safety Note: Working with 18650 lithium-ion cells requires care. Always use a high-quality Battery Management System (BMS). For premium electronic components, check our internal store or contact Pro Tronix support.