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Old 01-15-2004, 08:46 PM   #1
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Default Quick question about batteries

I'm new to this hobby and am just starting to work on building my own battery packs for the first time. I purchased a set of 18 loose cells from Hurricane. The cells are supposedly all "matched". However, the numbers on the individual cells are all slightly different. I pretty much understand what the numbers mean but am unsure how to best divide my 18 cells into 3 groups of 6. Is there any science or conventional wisdom on how best to do this or does it really not matter much as long as the batteries are all close.

My runtimes range from about 360 to 410 and my voltage numbers run from 1.41 to 1.49.

I can't seem to find specific info on this on a web site but if someone can point me to a site that will help me learn more I'm more than willing to read up more on this.

Edit: I meant to type 1.141 to 1.149

Last edited by plbman; 01-15-2004 at 09:15 PM.
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Old 01-15-2004, 08:50 PM   #2
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I would try putting them together in order of runtime as close as you possibly can.
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Old 01-15-2004, 08:52 PM   #3
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Default Re: Quick question about batteries

Quote:
Originally posted by plbman


My runtimes range from about 360 to 410 and my voltage numbers run from 1.41 to 1.49.
I would divide it into 1.41-1.45 and 1.45-1.49 and 380- and 380+. If for stock prioritise voltage, for MOD prioritise run time.

Hpe this helps
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Old 01-15-2004, 09:11 PM   #4
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try to choose the cells at first by runtime, then look at the avg volts and finally the internal resistance, but i think you'll can build your packs only by runtime selection...
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Old 01-15-2004, 09:12 PM   #5
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I love that maddona brittney avitar. lol
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Old 01-15-2004, 09:16 PM   #6
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I too got packs from Hurricane i built mine by run times. These are awesome packs. If you have any futher questions i'd call Brad at hurricane hes a top notch guy or post on the hurricane forum i'm sure Brad or Kevin would answer any concerns......good luck w/ your packs and racing
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Old 01-15-2004, 10:14 PM   #7
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PLBman.....Like others have stated I would just match up the runtime as close as you can per 6 cells. The change in voltage is not as big as running a 360 cell with a 410 cell would be. Just try to keep the Runtime close in the whole pack as best you can. If you have any more questions feel free to ask them in the Hurricane thread or give Brad a call at the shop....or if you race On-raod look for me or Brad at RSJ raceways we will help you out.
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Old 01-15-2004, 11:13 PM   #8
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I'd do it by runtime as a higher runtime pack will have the voltage distrbuted more evenly than a lower runtime.
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Old 01-16-2004, 03:24 AM   #9
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Not that I'm experienced in this, but I believe AWOLsoldier have a good point here. Because if one cell dumps before the others, performance will go down. Not to mention the fact, that that particular cell will be reverse charged. It will only be sligthly, but over time, the cells will differ more and more, thus making it worse.
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Old 01-16-2004, 08:19 AM   #10
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Thanks all.

I think I know how to proceed now.
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