Caps Assistance

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Did you guys do this? LOL


Trying out some caps. Wanted to get some assistance on really how to use them safely.

On a 12 and 16v system...

On the 12v are you doing 6 2.2v caps = 13.2v or what is the end voltage to go by. Dont want to over charge or under charge and have issues.

Yeah, not really an option with the draw that I would have. It would also not allow for many demos unless I did put in some type of breaker.

Alan wrote:

I think people are way to concerned with the balancing thing. I have accidentally charged my 6 cells.. 15v banks to like 16.2 before. And 15.5-15.8 about a million times. Now, ive never taken my banks apart to see how different the voltage per cell is. But im guessing its much different than what everyone thinks. I doubt 1 cell is at 2.5 while others are at 1v or something . I do know my voltage dropon 4 banks is much less than what fishes pretty banks drop to. At least what i thought i saw. 2 d5 drop 4 banks from 15.5 to 14.7-.8 for me.

For the price of the balancers I honestly don't think it can hurt. But like Alan said, I'm not going to actually check each cap.

http://item.mobileweb.ebay.com/viewitem?itemId=370657202452

how cost effective will it be if you can make caps work for sb, because 30 16 volt batteries is not cheap

chrysler300 wrote:

how cost effective will it be if you can make caps work for sb, because 30 16 volt batteries is not cheap

caps are no good for sb. there made to quickly discharge power aka in a 3 sec range. i however have not tried but i do make batteries for a living..lol that makes me smart..haha

Here the deal I can get a break on all my equipment except for batteries, I'm thinking 8 volt batteries might be the way to go I just can't afford 30 16 volt batteries

Im pretty confident they will work for SB. The issue is youll need an all to keep it. But i know people testing daily driving with the having good results

One guy told me caps will work if I have enough of them then never over charge them. the problem I'm having is nobody around here runs them

chrysler300 wrote:

One guy told me caps will work if I have enough of them then never over charge them. the problem I'm having is nobody around here runs them

Be the first.

Here is my cap setup. 9 banks of 7 per bank so 63 total.

Nice work!

So where can you find maxwell cap in bulk?

ebay

Im talking about a dealer

Maxwell sells the ones i have. But they are over a grand each! EBay is the only way .
The tecate group has em also. Just Google it .

I'd imagine some kind of restrictions are coming however... Sounds like 2 banks of caps are better than 2 batteries so.....

i heard this after finals last year, and well another year has passes

why should caps be restricted?????????????

Regardless.. caps are cheaper lighter smaller better.

So... just to verbalize some calculations:

Capacitance: 3000 F * 63 = 189000 F
Energy (start): 1/2 * 189000 * (2.7*15.4/18.9)^2 = 457.4 kJ
Energy (end): 1/2 * 189000 * (2.7*11.1/18.9)^2 = 237.6 kJ
Energy (change): 457.4 - 237.6 = 220 kJ --> over 30 seconds, that's 7,333 W (aka 10 horsepower)
Energy from alternator or power supply: 200 A * 15.0 V = 3,000 W

You can see for yourself that batteries are not necessary to support a 10kW system in this case.

In contrast, a gel cell deep cycle such as this one (random example):
Link to Apex AGM battery specs

If you use a logarithmic model, you can extrapolate the actual capacitance during a 30 second street beat run for a 110 Ah battery. I got 26 Ah. By comparison, 189000 F --> 52.3 Ah. This number doesn't tell the whole story, since it ignores the level of charge (not full for this setup).

If you use an exponential model, you can extrapolate the actual max current during a 30 second street beat run at 11.1V drop. I got 470 A... meaning 5000 W per battery.

Moral of the story, 1.5 big deep cycles will do the same duty as a huge capacitor bank. Both situations have similar rate of discharge (with minor benefits from the caps during transients).

Edit: For a Maxwell large module, it's 500 F @ 15.4 --> ~950 W for street beat per bank. It will take a few to support your alternator output ... but you can street beat with caps.

Is the quantity of batteries limited? Because ultracaps are actually to be considered batteries, they are WAY slower than a regular CAP. They were designed to replace batteries in telecommunications applications.

ultracap are not batteries, batteries are an energy producing device, ultracap produce no energy, they are only capable of storing it.

if you buy them brand new they actually come with a wire connected positive to negative grounding them out.

let me see you try that with an energy producing device and see what hapens

chrisbaldelli wrote:

So... just to verbalize some calculations:

Capacitance: 3000 F * 63 = 189000 F
Energy (start): 1/2 * 189000 * (2.7*15.4/18.9)^2 = 457.4 kJ
Energy (end): 1/2 * 189000 * (2.7*11.1/18.9)^2 = 237.6 kJ
Energy (change): 457.4 - 237.6 = 220 kJ --> over 30 seconds, that's 7,333 W (aka 10 horsepower)
Energy from alternator or power supply: 200 A * 15.0 V = 3,000 W

You can see for yourself that batteries are not necessary to support a 10kW system in this case.

In contrast, a gel cell deep cycle such as this one (random example):
Link to Apex AGM battery specs

If you use a logarithmic model, you can extrapolate the actual capacitance during a 30 second street beat run for a 110 Ah battery. I got 26 Ah. By comparison, 189000 F --> 52.3 Ah. This number doesn't tell the whole story, since it ignores the level of charge (not full for this setup).

If you use an exponential model, you can extrapolate the actual max current during a 30 second street beat run at 11.1V drop. I got 470 A... meaning 5000 W per battery.

Moral of the story, 1.5 big deep cycles will do the same duty as a huge capacitor bank. Both situations have similar rate of discharge (with minor benefits from the caps during transients).

Edit: For a Maxwell large module, it's 500 F @ 15.4 --> ~950 W for street beat per bank. It will take a few to support your alternator output ... but you can street beat with caps.

even the smart people dont yet know how caps work. Chris, Geoff doesn't have anywhere near 189,000 farad, he doesn't even have 10,000, or even 5000 fard.

in all actuallity a AA battery has more energy power than a single capacitor cell, but a battery cannot discharge it's energy like a cap can, that is why the caps are way better.

and as far as limiting them in usaci, it was brought to the R&E committee before 2007 world finals by none other than bill gass. He was the one that did the initial research and decided to try them out.

unfortunatly the car they were ran in in 2007 was a last minute build and underpowered so they went mostly unnoticed. I've ran them ever sense trying to keep them a queit as possible.

l&c ran them as well in 2010 then moonie ran them and people started looking around and found them cheap on the internet and the flood gates have been open ever since.

at a show last year i had a kid not knowing what he was looking at complain to ralph at a show saying i had more than the allowed amount of batterires. ralph looked and said something to the effect, ohh those are just capacitors, they arent' worth a dang, you'd be better off on just batteries.

so i dont think will change to soon.

but why should they, we are at what, like $400 for decent battery now, wheras $400 of these will do better than 3 - $400 batteries.

and you can get new modules from maxwell, or one of the sites linked on there webpage, they are spendy, but not 1k each like fish said, that was the 7 years ago price, they are now about half that new from them, and half that one ebay, or 225 or so per module.

the used ones are just as good for the money

kickercrx wrote:

ultracap are not batteries, batteries are an energy producing device, ultracap produce no energy, they are only capable of storing it.

if you buy them brand new they actually come with a wire connected positive to negative grounding them out.

let me see you try that with an energy producing device and see what hapens

I said they should be considered as, on a battery limited class.

kickercrx wrote:

at a show last year i had a kid not knowing what he was looking at complain to ralph at a show saying i had more than the allowed amount of batterires. ralph looked and said something to the effect, ohh those are just capacitors, they arent' worth a dang, you'd be better off on just batteries.

so i dont think will change to soon.

Are you saying that the ultracap use is unlimited on a limited battery number class?

Go under tools here: http://www.maxwell.com/products/ultracapacitors/products/16v-small-modules

You can calculate the number of ultracaps needed,

I ran a basic scenario: 18V dropping to 14V in 2 seconds under 2000A of load.

Required 28x BCAP3000s (4 paralleled sets of seven).

That is over 30kW input averaged over 2 seconds.

capacitors are and have always been unlimited in USACI

Ok I just went and read the rules.

You have to be kidding then...

Ultracaps are not caps, they are ELDC.

Ultracaps were designed to store energy for much larger periods of time compared to capacitors. You don't really need a battery if you have enough CHARGED Ultracaps. If you guys are on a battery limited class and filling the vehicle with ultracaps, oh boy. hahaha.

I'm sorry to come as an A$% but do you realize this? Is everyone aware that using ultracaps is just circumventing the battery limitation rule?

the physical make up between a battery and a cap s what makes them differant.


a battery and a cap is not the same

we have alot of pissed off peiople because someone ficured out how to, and what caps to run to ghet this done.



these caps are designed to store high levels of ebergy in many differant applications for what ever you may need it for.

and noone is ever sorry for being an ass