Batteries
Battery Series Parallel Calculator
Use Battery Series Parallel when pack energy is the quantity you need. Enter cells in series, parallel strings, cell nominal voltage, and cell capacity, then compare the answer with the equipment or operating limits that apply to your case.
Enter values for Pack energy
Do not mix values recorded under different conditions.
Before entering values
Separate nameplate capacity from measured usable capacity. A source note beside each entry makes the result reproducible.
At least one field has a positive lower bound because it appears in a denominator. Convert units once, retain the original reading, and verify the converted magnitude. The broader analysis may also use LED Array Configuration Calculator.
- Cells in series
- Default example: 4. Enter cells in series.
- Parallel strings
- Default example: 3. Enter parallel strings.
- Cell nominal voltage
- Default example: 3.7 V. Enter cell nominal voltage in V.
- Cell capacity
- Default example: 2.5 Ah. Enter cell capacity in Ah.
Before accepting the number
An unlabeled assumption can make an otherwise correct result unusable.
Compare the magnitude with a quick independent estimate.
Pack energy: calculation method
Here, Pack energy is obtained from energy = series × parallel × cell voltage × cell capacity. The participating entries are Cells in series, Parallel strings, Cell nominal voltage, and Cell capacity.
Using the loaded examples gives 111.00 Wh. Your saved case should identify where each entry came from.
Calculate pack voltage, capacity, and energy from cell ratings and configuration. For the companion pack energy calculation, open Battery Pack Stored Energy Calculator.
Interpreting the answer
Use Pack energy as one quantified check within the larger decision. Compare it with manufacturer discharge data at the intended rate.
A result without its source conditions is difficult to compare or audit. If you also need total modules, continue with Solar Array Configuration Calculator.
Compare two operating cases
Change Cells in series from 4 to 5 with every other entry unchanged. The result changes from 111.00 Wh to 138.75 Wh.
This isolates one variable; a real system may change several at once.
What the formula leaves out
Use matched cells and verify BMS, current, thermal, and enclosure limits.
The equation does not include temperature, cell imbalance, BMS cutoffs, aging, and rate dependence. Document which effects were checked elsewhere in the analysis.
Use voltage and capacity values from the same battery condition. For stored energy, use Amp-Hour Watt-Hour Calculator.
Questions from practical use
What does a zero entry represent?
Leave the case unfinished until the real value is known rather than entering a placeholder zero.
Which operating condition belongs in this calculation?
Measured and rated values can represent different states. Use voltage and capacity values from the same battery condition.
What should I verify beyond the displayed inputs?
Use matched cells and verify BMS, current, thermal, and enclosure limits. Also consider voltage sag, thermal rise, charge taper, and balancing.