Hydrogen Electrolyzer & Fuel Cell Manufacturing worked example

Cell Voltage Variation at 2.3% target out-of-spec cell rate: a worked example

Push target out-of-spec cell rate up to 2.3% and the picture changes. This example computes every intermediate figure at that operating point. Use it when a quality engineer is reviewing the per-cell voltage map from end-of-line test and needs a clean number for the daily quality report and the cell-balancing decision.

The inputs for this scenario

  • Cells outside the cell-voltage spec window: 3 cells (unchanged)
  • Total cells in the stack: 100 cells (unchanged)
  • Target out-of-spec cell rate: 2.3 % (raised for this scenario; the documented default is 2)

Working through the calculation

  • Applying the documented formula (Out-of-spec cell rate = cells outside spec ÷ total cells in stack × 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 3 % for out-of-spec cell rate, the number this scenario is built around.
  • At this operating point the engine returns -0.7 points for cell voltage spec gap.
  • At this operating point the engine returns 3 count for cells outside spec window.
  • At this operating point the engine returns 100 count for total cells in stack.

How this compares with the baseline

  • Against the tool's baseline example, where target out-of-spec cell rate sits at 2% and the headline result is 3 %, this scenario lands almost exactly on the baseline at 3 %.
  • It computes the percentage of cells outside the voltage spec window and the gap between that rate and your target out-of-spec rate. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Out-of-spec cell rate: 3 % (headline result)
  • Cell voltage spec gap: -0.7 points
  • Cells outside spec window: 3 count
  • Total cells in stack: 100 count

Run it with your numbers

  • Every input above is editable in the live Cell Voltage Variation calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.