Okay; I probably ask the wrong question. Let me formulate another way.

If I recall well, the electrical law for capacitors is: Q = U x C = I x t

Where:
Q is the Load (Coulomb) - in french, la charge
U is the Voltage
C is the capacity (Farad)
I is the intensity (Amps)
t is the time (second)

A.- Is it correct/acceptable to apply this law to LEDs?

B.- Am I right to think that if I change the charging voltage of the LED, I'm going to modifiy its Load?