220 F, 2.7 V, 5 mOhm ESR — the hold-up energy and the IR drop
The SCCX50B227SSBLE is a 220 F supercapacitor from the SCC LE series, rated at 2.7 V with a maximum ESR of 5 mOhm at 1 kHz. This combination defines the usable energy window: at 2.7 V the stored energy is 801 J, but the 5 mOhm ESR sets the peak current the cell can deliver before the IR drop eats into the voltage headroom. For a 10 A pulse, the immediate drop is 50 mV — negligible for most hold-up circuits, but at 50 A the 250 mV drop starts cutting into the downstream regulator's minimum input. The -10% / +30% tolerance on capacitance means the minimum guaranteed value is 198 F, while the maximum can reach 286 F. Design the hold-up time budget at the low end — the extra capacitance on the high side only improves margin.
Lifetime and thermal budget — 1000 hours at 60 °C
Rated lifetime is 1000 hours at 60 °C with full rated voltage applied. Every 10 °C drop below 60 °C roughly doubles the life — at 40 °C the expected life is around 4000 hours, and at 25 °C it extends well past 10,000 hours.