Electrical capacitor.. need your opinion

[Jerboy]

Somebody posted this link in off topic and from my experience, I am having hard time believing the capacitor value he claims. That capacitor couldn't be much bigger than 1 1/2 canned spaghetti sauces stacked together and I have not seen capacitors capable of discharging energy rapidly and at the same time hold as much as 1270joules. Electrolytic capacitorsof that size I've handled holds about 100-200joules. If it was really 625V 6500µF it will hold 1270joules(1/2 x 6000E06 x 625^2=1269.6 joules ). Do you guys think this guy's faking it?

 

[Killbat]

I have some similar caps sitting around here, his claims aren't outlandish.
He's going to need some heftier cabling between the cells in his bank, though.

 

[Evadman]

Ya, that looks like 12 or 14 gauge. That's gonna get real hot when discharged. I used 4 gauge, but I did not have anywhere near that many Caps.

 

[CTho9305]

thats insane. anyway, search around slashdot and see if you can find the railgun post from a while back, I think something is here. one of the project used a LOT of caps like that to power it.

edit: found the article

 

[Evadman]

Wow, the one that we built at ISU was not like that. It was a plastic tube with magnet wire wrapped around it. Then we used a nail with the head shaved off as the projectile. We would push between 20 and 80 amps though the wire. for all intents and purposes it was like the door lock mechanism on your car. ( read: solonoid )but instead of pulling down on the lock it fired the nail out the end. The way they have it set up it would take a monstorus amount of amps, but they would be able to achieve higher velocities.

<edit>
These guys are at 5.6Kj
</edit>