Yes, but the cap holds the voltage up higher, by holding a charge up to that level.
A 20F cap will hold twice the charge of a 10F cap, meaning you can draw 1A out of it for twice as long, before the voltage drops 1 volt.
A battery on the other hand holds a massive charge, and you can draw several amps out of it before it drops a volt.
Correct?

 

yeah you can generally on the order of 10-15 amps from most batteries before causing a voltage dip. however most batteries have a pretty high ESR and will drop down noticacly with only a 40 amp draw.

Mind you.. by the time your dipping into the battery you've allreay dropped 2 volts from the alternators ideal charge rate. whis is 17.xx% -ish

 

you mean 14.4 volts not 17.xx-ish rite ?
if not your wrong . sorry if you miss wrote

 

17% voltage drop

 

sorry cant see