EV & Battery Manufacturing worked example

Battery Cell Rework Rate at 1.73% target maximum rework rate: a worked example

What does the result look like when target maximum rework rate reaches 1.73%? The full calculation is worked below with real intermediate numbers. a cell line needs to measure rework burden from defects, retests, visual issues, or process holds

The inputs for this scenario

  • Cells requiring rework: 620 cells (unchanged)
  • Total cells processed: 48,000 cells (unchanged)
  • Target maximum rework rate: 1.73 % (raised for this scenario; the documented default is 1.5)

Working through the calculation

  • Applying the documented formula (Cell rework rate = cells requiring rework รท total cells processed) to the inputs above produces each figure below.
  • At this operating point the engine returns 1.29 % rework for cell rework rate, the number this scenario is built around.
  • At this operating point the engine returns 0.44 points for rework rate gap to limit.
  • At this operating point the engine returns 620 cells for cells requiring rework.
  • At this operating point the engine returns 48,000 cells for cells processed.

How this compares with the baseline

  • Against the tool's baseline example, where target maximum rework rate sits at 1.5% and the headline result is 1.29 % rework, this scenario lands almost exactly on the baseline at 1.29 % rework.
  • A figure at this level is achievable when target maximum rework rate is genuinely sustained, not just peaked for a shift. It treats all rework as equivalent; it does not weight a quick re-seal against a teardown, nor does it capture cells that fail rework and become scrap.

Results at a glance

  • Cell rework rate: 1.29 % rework (headline result)
  • Rework rate gap to limit: 0.44 points
  • Cells requiring rework: 620 cells
  • Cells processed: 48,000 cells

Run it with your numbers

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

Last reviewed 2026-05-12.