Hydrogen Electrolyzer & Fuel Cell Manufacturing worked example

Stack Assembly Yield at 99% target first-pass stack assembly yield: a worked example

Push target first-pass stack assembly yield up to 99% and the picture changes. This example computes every intermediate figure at that operating point. Use it on the daily tier board when stack build cells, MEAs, bipolar plates, gaskets, and end plates have to flow through assembly with a known first-pass rate before warranty exposure builds up.

The inputs for this scenario

  • Stacks passing first-time leak, torque, and voltage checks: 232 stacks (unchanged)
  • Total stacks attempted in the same period: 250 stacks (unchanged)
  • Target first-pass stack assembly yield: 99 % (raised for this scenario; the documented default is 95)

Working through the calculation

  • Applying the documented formula (First-pass stack assembly yield = stacks passing first-time ÷ total stacks attempted × 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 92.8 % for first-pass stack assembly yield, the number this scenario is built around.
  • At this operating point the engine returns 6.2 points for yield gap to target.
  • At this operating point the engine returns 232 count for stacks passing first-time.
  • At this operating point the engine returns 250 count for total stacks attempted.

How this compares with the baseline

  • Against the tool's baseline example, where target first-pass stack assembly yield sits at 95% and the headline result is 92.8 %, this scenario lands almost exactly on the baseline at 92.8 %.
  • It computes first-pass stack assembly yield as a percentage and the point gap between that yield and your target. 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

  • First-pass stack assembly yield: 92.8 % (headline result)
  • Yield gap to target: 6.2 points
  • Stacks passing first-time: 232 count
  • Total stacks attempted: 250 count

Run it with your numbers

  • Every input above is editable in the live Stack Assembly Yield calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.