EV & Battery Manufacturing worked example

Cell Aging Inventory Days with released aged-cell inventory on hand of 360,000 cells: a worked example

This scenario runs the cell aging inventory days calculation on the strong side: released aged-cell inventory on hand of 360,000 cells, with every other input held at its documented default. a cell plant needs to balance aging hold inventory with grading and module assembly demand

The inputs for this scenario

  • Released aged-cell inventory on hand: 360,000 cells (raised for this scenario; the documented default is 144,000)
  • Daily downstream cell draw: 24,000 cells / day (unchanged)
  • Aging buffer safety factor: 1.2 x (unchanged)

Working through the calculation

  • Applying the documented formula (Unprotected aged-cell days = released aged-cell inventory รท daily downstream demand) to the inputs above produces each figure below.
  • At this operating point the engine returns 12.5 days for protected aging inventory days, the number this scenario is built around.
  • At this operating point the engine returns 15 days for unprotected aged-cell days.
  • At this operating point the engine returns 360,000 cells for released aged-cell inventory.
  • At this operating point the engine returns 24,000 cells / day for daily cell demand.

How this compares with the baseline

  • Against the tool's baseline example, where released aged-cell inventory on hand sits at 144,000 cells and the headline result is 5 days, this scenario comes in 150% above the baseline at 12.5 days.
  • Use it for daily aging-room replenishment decisions and to check whether released stock can survive an aging-line stoppage. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Protected aging inventory days: 12.5 days (headline result)
  • Unprotected aged-cell days: 15 days
  • Released aged-cell inventory: 360,000 cells
  • Daily cell demand: 24,000 cells / day

Run it with your numbers

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

Last reviewed 2026-05-12.