Battery Pack Builder Calculator
The RideWattly battery pack calculator helps you plan safe, realistic lithium packs for electric bicycles, scooters, and DIY energy projects. Whether you need an 18650 battery builder layout, a 21700 battery calculator for higher-density packs, or a quick check for common voltages like 52V battery pack cells, this tool combines electrical math, visualization, and exportable specs in one place.
Use it as a battery pack size calculator to estimate overall dimensions and weight from cylindrical or prismatic formats, then validate with your BMS, spot welder plan, and cell datasheets. For community builders, it doubles as an ebike battery builder assistant: presets, compare mode, and local saves make iteration fast without accounts or sign-ups.
Frequently asked questions
How accurate are voltage and energy numbers?
Nominal voltage uses your per-cell nominal value multiplied by series count. Full and empty voltages assume classic Li-ion endpoints (4.2V / 3.0V per cell) for planning — always follow your cell vendor’s limits and BMS settings.
How should I interpret “estimated max current”?
It multiplies parallel count by the cell’s entered max continuous discharge. Real packs depend on welding, nickel width, temperature, and BMS — treat this as an upper planning hint, not a guarantee.
What do the range modes mean?
Eco / Normal / Aggressive use different assumed energy consumption per kilometer. They’re benchmarks only; your motor, gearing, rider weight, and wind dominate real results.
Can I use prismatic cells?
Yes — select prismatic / custom and enter your own nominal voltage, capacity, mass, and discharge. Size estimates use editable bounding dimensions in the script’s prismatic defaults.
Is my data stored on a server?
Saves, theme preference, and last session restore stay in your browser (localStorage). Sharing uses a link-encoded snapshot; don’t treat links as private if they contain detailed build data.