Battery Pack Configurator (Ns × Mp)
Series/parallel cell counts for a target voltage and capacity — Li-ion, LiFePO₄, NiMH and lead-acid presets with voltage windows.
Series strings need a BMS that balances every cell group — never build unbalanced lithium packs. Parallel groups must be assembled from cells at the same state of charge (huge currents flow otherwise). Match cells by capacity and internal resistance within a pack; mixing old and new cells drags the whole pack to the weakest cell's performance.
Battery Pack Configurator computes the series/parallel cell layout for a target pack voltage and capacity — free, instant and private in your browser. E-bike and power-wall builders, robotics teams and anyone speccing lithium packs use it to skip the datasheet algebra: type your numbers, read the answer with the substituted formula shown step by step, and share an exact permalink of the calculation.
About Battery Pack Configurator (Ns × Mp)
Battery Pack Configurator computes the series/parallel cell layout for a target pack voltage and capacity using the standard engineering relation: Ns = V(pack)/V(cell,nom), Mp = Ah(pack)/Ah(cell); E = Ns·Mp·Vnom·Ah. Worked live: a 36 V / 10 Ah e-bike pack from 3.6 V / 3.0 Ah 18650s comes out 10S4P — 40 cells, 432 Wh. The result recalculates on every keystroke, the worked-example panel shows your numbers substituted into the formula, and the Copy permalink button encodes the inputs in the URL so a colleague opens exactly your calculation. Everything runs client-side — nothing you type leaves your device.
How to use Battery Pack Configurator (Ns × Mp)
- 1Enter your values — the tool starts with realistic defaults for this exact use case, so the worked example is meaningful immediately.
- 2Read the live result and the worked-example panel, which substitutes your numbers into the formula step by step.
- 3Adjust any input to compare scenarios, then use Copy result or Copy permalink to share the calculation.
Why use Battery Pack Configurator (Ns × Mp)?
- ✓Implements the real formula — Ns = V(pack)/V(cell,nom), Mp = Ah(pack)/Ah(cell) — with the substitution shown, not a black box
- ✓Built for e-bike and power-wall builders, robotics teams and anyone speccing lithium packs
- ✓Copy result and permalink buttons — share the exact calculation in a README, forum answer or design review
- ✓100% free, no sign-up, runs entirely in your browser (works offline once loaded)
Frequently asked questions
How do you calculate battery pack?+
The series/parallel cell layout for a target pack voltage and capacity follows Ns = V(pack)/V(cell,nom), Mp = Ah(pack)/Ah(cell); E = Ns·Mp·Vnom·Ah. For example, a 36 V / 10 Ah e-bike pack from 3.6 V / 3.0 Ah 18650s comes out 10S4P — 40 cells, 432 Wh. The calculator applies the same relation and shows the substituted arithmetic so you can verify every step.
What do 10S4P and similar codes mean?+
10 cell groups in Series sets the voltage (10 × 3.6 = 36 V nominal); each group is 4 cells in Parallel setting capacity and current ability. Voltage stacks in series, amp-hours stack in parallel.
Can I mix old and new cells to reach the count?+
Don't. Capacity and internal-resistance mismatch makes the weakest cells work hardest, age fastest and drift in voltage — the BMS will limit the whole pack to the worst cell, and in parallel groups mismatch causes circulating currents. Build packs from matched, same-batch cells.
Is the Battery Pack Configurator free and private?+
Yes — completely free with no sign-up or usage limits, and it runs entirely in your browser: the values you enter are never uploaded or stored on a server.
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