On September 22, 2026, CATL started trial production on the first two production lines of its cell plant in Debrecen, Hungary, stating that the purpose is "to set up, optimise and validate the production equipment and manufacturing processes ahead of series production"¹. If validation is defined as demonstrating a defect rate, a zero-failure demonstration at 95 % confidence requires 29,956 cells for 100 ppm and 299,572 cells for 10 ppm. Compared with an assumed aging-judgment lead time of 14 days, aging governs the trial length at a 100 ppm target, while sample accumulation governs it at 10 ppm. The second line halves the time only when samples are pooled, and…