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Discussion Starter #1
Right now I have the odyssey AGM PC625 that can output 625A for 5s and has an MCA of 350A, weighing 13.lb.

Is there a lead acid battery around that weight that can beat that?
 

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Probably not. Oddesey batteries are what pretty much all of the experimental aviation crowd use because they can use a lighter battery and still crank the engine + prop.

FireFly promised to do better, but went under.
 

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Per the posted performance graphs, Enersys 2.5 Ahr lead acid D cells would do about twice the amps per pound of battery. You would have to use many of them! You would do well to test some yourself before a major investment, obviously.

http://www.enersysreservepower.com/images/scccgrph.gif
http://www.enersysreservepower.com/scps.asp

Right now I have the odyssey AGM PC625 that can output 625A for 5s and has an MCA of 350A, weighing 13.lb.

Is there a lead acid battery around that weight that can beat that?
 

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cold cranking amps is measured as amperage that can be held for 30 seconds before dropping to no lower than 8 volts if I remember correctly. 625 amps for 5 seconds sounds like much less than a CCA test to me. Just for comparison reference.
 

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Discussion Starter #6
I am actually using it for a performance EV vehicle. So 2 requirements that I require are:
- Output amperage for 10 seconds (would like this to be as high as possible up to 800A)
- How long the batteries can produce around 250-300A for (would like this value to be rougly 8-10min).

What values would you use for EVs?
 

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You can do lots of fancy math, but I think the easiest way is to go to the links in my last post. The enersys site has curves for how long their batteries produce various amounts of current and power.
I am actually using it for a performance EV vehicle. So 2 requirements that I require are:
- Output amperage for 10 seconds (would like this to be as high as possible up to 800A)
- How long the batteries can produce around 250-300A for (would like this value to be rougly 8-10min).

What values would you use for EVs?
 

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I am actually using it for a performance EV vehicle. So 2 requirements that I require are:
- Output amperage for 10 seconds (would like this to be as high as possible up to 800A)
- How long the batteries can produce around 250-300A for (would like this value to be rougly 8-10min).

What values would you use for EVs?
If you need 300A for 10 minutes that implies a minimum capacity of 50Ah. Because of the Peukert effect, however, you'll need about twice that capacity, or around 100Ah. You aren't going to find a 50Ah lead-acid cell that weighs 15lbs, much less a battery, much less as 100Ah battery!

In fact, I think you'd have a tough time getting down to 15bs for a 12V/50Ah battery with LFP cells... I just checked and it seems a TS 60Ah cell weighs 2.5kg so 4 of them will weigh 10kg, or 22lbs.
 

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I took a look a little deeper into it, seems 2007 they used the A123 KillaCycle borrowed pack but went back to lead-acid while they figured out their lithium options throughout 2007 through 2009 as I understand the site. They are using Dow Kokam cells now.

http://www.plasmaboyracing.com/history/2007l.php
"The Enersys 14 lb. batteries (formerly Hawker) dished out the 750 amps each without any trauma whatsoever."

Better info on the pack is in the beginning of 2007 when they switched to the 16Ah cells - 46.875C from lead acid?! I didn't know it was possible until reading that now. Managed 3 years of racing before the pack wasn't worth the replacements giving a 12.694 at 96.87mph one of the final two runs.
http://www.plasmaboyracing.com/history/2007e.php
 

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Discussion Starter #11
Wow those 16XEs look awesome. But I can't seem to find them anywhere.

Where can I buy these? Or at least see the detailed specs of the battery. They don't seem to appear anywhere except for the plasma boy car.
 

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Wow those 16XEs look awesome. But I can't seem to find them anywhere.

Where can I buy these? Or at least see the detailed specs of the battery. They don't seem to appear anywhere except for the plasma boy car.

Try this site. Enersys Odyssey battery dealer locator.

http://www.odysseybattery.com/locator.html

Just click on yor state and a list of dealers for yor state will pop up.
 
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