supercapcacitor based battery

[seza]

Hi all;

Please excuse me if my question appear basic;

If I am to make a super dupper large capacitor that is able to hold a lot of charge (using graphene for example);
1) is there any way I can prevent it from self discharging; I dont mind a small amount of self disharging
2) how can I use the power stored in the cap over a longer period say hours or even days?

thanks in advance
seza

 

[BobK]

What is your application? In most cases batteries are a better choice.

Bob

 

[Alec_t]

If you want to use the power over a long period you must minimise the load current.
A DC-DC converter will be needed if the load requires a constant voltage (as many do; hence the use of batteries as Bob says).

 

[seza]

Thanks guys,

I just think it is about time to look into cap based energy storage with all these wonderful new materials being discovered such as graphene etc ...
I am aware of the limitations of traditional caps but I am hoping that some well read clever people on this forum can come up with some ideas to mitigate those limitations .... the more ideas the merrier!?

 

[(*steve*)]

There are several considerations which require (usually) that you incorporate a charge controler and some sort of output conditioning.

Because the voltage across a capacitor rises and falls with the charge, you need some mechanism to ensure that charging is controlled. A large part of this is to ensure that the voltage across the individual capacitors does not exceed the rated maximum. This is especially important when capacitors are connected in series.

Also, you need to (typically) produce a constant output voltage from the varying voltage across the capacitor bank. This is typically done using some form of switch mode regulator.