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Here's another link:

http://www.greencarcongress.com/2006/02/mit_carbon_nano.html

Commercial ultracapacitors achieve an energy density of around 6 Wh/kg; NiMH batteries of around 60 Wh/kg; lithium-ion batteries of around 120 Wh/kg. ... The MIT analysis shows that the CNT ultracapacitor could have an energy density higher than 60 Wh/kg, a power density greater than 100 kW/kg (three orders of magnitude higher than batteries), and a lifetime longer than 300,000 cycles. At 60 Wh/kg, the CNT ultracapacitors would have comparable density to NiMH batteries.
Another factor is the charge/discharge efficiency. I've seen figures for NiMH ranging from 70% to 85%, and Li-ion of > 95%. Capacitors may be even higher, and should not degrade over time.
 

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The problem I see that isn't mentioned is how capacitors operate electrically. Voltage is proportional to charge with capacitors. Batteries ideally maintain their voltage until depleted.

I suppose though with an efficient voltage converter, the capacitor's varying voltage could be regulated.
 

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DanMan32 said:
The problem I see that isn't mentioned is how capacitors operate electrically. Voltage is proportional to charge with capacitors. Batteries ideally maintain their voltage until depleted.

I suppose though with an efficient voltage converter, the capacitor's varying voltage could be regulated.
Don't forget the "FLUX CAPACITOR" ...DAN!!!! "A three leaded ohms law defying work of Doc Brown genius...!

...seriously, regulating 200volts would be quite a feat under the consumption levels consumed by th Pri....cap would be huge just to overcome the losses of the cap after it falls to a low state of "charge" The regulator would put such a high demand in amperage in order to hold the "voltage" after it fell to anything south of 200 volts.....then..not to mention the losses encountered in converting to AC.....I don't think were close enough for this type technology yet. "Nothing against MIT of course"

...lunch next week Dan? we'll solve it then!
 

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How about a bank of capicitors controlled by a processor? By keeping some in varying states of discharge while others in different states of charging?

SMOP (Simple matter of programming).
 

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RealAle said:
How about a bank of capicitors controlled by a processor? By keeping some in varying states of discharge while others in different states of charging?

SMOP (Simple matter of programming).
...it's still "just one big capacitor"...charge / discharge...it's all relative whether this one is up while that one is down or passing each other in 'potential". Your still stuck with ohms law....
 
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