ultracapacitor as batteries and farad problem

[ejonesss]

i have seen where ultracapacitors have some amazing power where 1 user used them to start a car.

but after reading where seriesed capacitors have less farads so a series of 20 2.7v 400 farad ultracapacitors will not give you the full 400 farad upon recharge


https://www.tindie.com/products/burkleypatterson/27-volt-400-farad-ultracapacitor/

if this is true about less farads for seriesed ultracapacitors then i was wondering if the charger is broken up into single cell charging like done like this

taken from http://endless-sphere.com/forums/viewtopic.php?f=14&t=8975&p=140474&hilit=voltphreak#p140474

would above setup work to restore the lost farads?

looks like a similar thing is happening in the atx power supply with the 110/220 selector switch, 2 capacitors and rectifying diodes.

 

[ejonesss]

i was thinking because they only charge up to the voltage that is applied across them by putting 5 volts across for example a series of 2 2.7 volt caps you will only charge each up to 2.5 volts.

if you can put 2.7 volts across each one you then keep the 400 farad because each one will charge up fully basically distributing the charge more evenly like a bms does for balancing

and yes i did see that article earlier but no explicit mention of less capacity in series.

and another thing does the farads even matter in run time since maybe it is the can size?

i have seen for example a 400 uf 200 volt cap used in large stereo amplifier would have more punch and make a bigger spark when shorted because it is 1 inch diameter by 3 inches long than

a 3300 uf 12 volt cap found in the 12 volt section of a atx power supply or the 400 uf 200 volt cap that is in a camera flash that is the size of a aa battery if the same load is put on it

and it was google where i did the search for the less capacity thing but all the texts and pictures showed charging the series from 1 power supply not multiple power supplies like what the 110/220 selector does on the power supply.

 

[parabellum]

I think, you should reread explanation of capacitance(http://en.wikipedia.org/wiki/Capacitance), you do not (fully) understand what Farad is. It is very different (more complex) animal to Ampere for example, but I think you are trying to handle those two equally.