EV & Battery Manufacturing worked example

Battery Module Assembly Yield at 99% target module yield: a worked example

What does the result look like when target module yield reaches 99%? The full calculation is worked below with real intermediate numbers. a module line needs to measure whether assembly and test output is meeting the yield target before packs are starved

The inputs for this scenario

  • Accepted modules: 1,880 modules (unchanged)
  • Total modules built/tested: 2,000 modules (unchanged)
  • Target module yield: 99 % (raised for this scenario; the documented default is 95)

Working through the calculation

  • Applying the documented formula (Module assembly yield = accepted modules รท total modules built/tested) to the inputs above produces each figure below.
  • At this operating point the engine returns 94 % module FPY for module assembly yield, the number this scenario is built around.
  • At this operating point the engine returns 5 points for module yield gap to target.
  • At this operating point the engine returns 1,880 modules for accepted modules.
  • At this operating point the engine returns 2,000 modules for modules built/tested.

How this compares with the baseline

  • Against the tool's baseline example, where target module yield sits at 95% and the headline result is 94 % module FPY, this scenario lands almost exactly on the baseline at 94 % module FPY.
  • A figure at this level is achievable when target module yield is genuinely sustained, not just peaked for a shift. A scrapped module embeds many good cells, so this yield understates the true loss unless you separately value recoverable cells from teardown.

Results at a glance

  • Module assembly yield: 94 % module FPY (headline result)
  • Module yield gap to target: 5 points
  • Accepted modules: 1,880 modules
  • Modules built/tested: 2,000 modules

Run it with your numbers

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

Last reviewed 2026-05-12.