Battery Series Parallel Energy Calculator
Calculate nominal pack voltage, amp-hour capacity, watt-hours, cell count, cells-only mass and cost for an entered identical-cell series/parallel model.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Multiply cell voltage by series count and cell Ah by parallel count; compare nominal energy, cell count and cells-only resources.
Vpack=Vcell×series; Ahpack=Ahcell×parallel; Wh=Vpack×Ahpack
Worked example
Four 3.7 V cells in each of two equal parallel strings, each cell rated 3 Ah, give 14.8 V, 6 Ah and 88.8 Wh nominal energy from eight cells.
Assumptions and input details
An identical-cell arithmetic model, not battery-pack design approval or wiring instructions. Nominal Wh is not guaranteed usable energy. Cell compatibility, imbalance, temperature, current rating, BMS, protection, interconnects and product series/parallel restrictions are excluded. Maximum voltage is only the entered per-cell value multiplied by series count; mass/cost exclude all non-cell parts.
References: Victron Energy: series/parallel voltage and capacity arithmetic
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
The 19 mass definitions distinguish avoirdupois and troy measures, metric and regional measures. Japanese kin is 600 g; mainland Chinese shijin is 500 g.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
SI prefixes are explicit: for example, milli means one thousandth, micro one millionth and kilo one thousand. Changing a unit changes the interpretation of the entered number.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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