The problem is, the modern cycle testing methods. A heap of rapid charge and discharge, maybe 500 cycles or 1,000 cycles, measure the degradation and extrapolate a cycle life down to .... what ever capacity the manufacturer wants really, they are paying for the testing after all, so down to acceptable Lead Acid battery standards of 60% capacity and drawn down to 9.5v using the lead acid C20 test rate ...... probably could achieve 100,000 cycles ..... if that were possible inside the general 10 yr capacitor calendar life ...... that's 2.75 full chargers and discharges, every day, not possible at a C20 rate .... even back to back with no rest between cycles, that would require a C4 load and charge rate, even the little 51kw battery in our MG4, that's roughly a 35 amp load or 13kw, and a 14kw charge rate .....
T1 Terry