-
Pylontech’s 588 Ah and 601 Ah LFP Cells Enter Mass Production — Why Energy-Weighted Availability Stays the Same When the Cell Count Halves
On September 21, 2026, Pylontech began mass production of 588 Ah and 601 Ah prismatic LFP ESS cells at its Hefei base and named "fewer cells and interconnections" as a benefit of the larger format¹. Under a reverse-engineered assumption of 416S strings, a 100 MWh-class site drops from 99,840 cells to 52,000 cells (−47.9 %), and string trips caused by cell-count-proportional faults fall at the same rate. Each trip, however, now removes 800.1 kWh instead of 418.0 kWh (1.91×), so the energy-weighted unavailability stays at 0.0285 % regardless of cell capacity. The mean is unchanged and only the tail gets heavier: the probability of losing 0.8 % or more of…

