How Many Cells Do You Need?
Enter your target pack voltage and how much energy you want (in watt-hours, amp-hours, or range in miles), pick a cell, and this calculator works out the series/parallel layout, total cell count, pack weight, and maximum continuous current.
Target pack nominal voltage (e.g. 36, 48, 52).
Target energy in watt-hours.
- Nominal voltage
- 46.8 V
- Capacity
- 12.0 Ah
- Energy
- 562 Wh
- Cell count
- 52
- Total weight
- 2.37 kg
- Max continuous
- 60 A
How the math works
Series (S) sets the voltage. Each cell has a nominal voltage (typically 3.6–3.7 V for lithium-ion), so the number of cells in series is your target pack voltage divided by the cell's nominal voltage, rounded to the nearest whole cell.
Parallel (P) sets the capacity. Cells wired in parallel add their amp-hours together, so the number of parallel groups is your target capacity divided by a single cell's capacity, rounded up so you never come up short.
Total pack energy is S × P × cell capacity (Ah) × cell nominal voltage. Maximum continuous current scales with the number of parallel groups: P × the cell's rated continuous current.
Want the full walkthrough with worked examples for ebikes, e-skateboards, and drones, plus how to choose between high-capacity and high-drain cells? Read How Many Cells Do You Need? — the complete guide.