Plate balancing in Sealed LeadAcids??

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Plate balancing in Sealed LeadAcids??

Weve all discussed balancing strings of cells in the past, but no one ever mention that each 12v SLA actually has 6 plates in series!
DO these plates all self balance as they are sloshing around in the same electrolyte?

If so surely 24v (or even 36v) SLAs would be great rather than making that voltage up from strings of 12v batteries?

Im sure Ive seen 24v SLAs before. So am I right these cant get unblanced like 2 x 12v slas could??

reikiman's picture
Last seen: 10 months 21 hours ago
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Re: Plate balancing in Sealed LeadAcids??

Uh.. I'm somewhere around 90% certain that a lead-acid battery does not have common electrolyte between cells.

In any case the behavior of the batteries in my EV car indicates that individual cells in lead acid batteries do not "self balance". The pack behaves fine except that on every drive one cell in one of the batteries gets really hot and spits out a bit of battery fluid.

Last seen: 1 month 3 weeks ago
Joined: Wednesday, July 15, 2009 - 15:49
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Re: Plate balancing in Sealed LeadAcids??

Probably has not been discussed for Pb-acid batteries were powering vehicles like golf carts and NEV's for a long time with out battery balancers. I think one of the earlier balancer made was the Rudman regulators invented by Rick Rudman. The other fact is usually rather massive long time high current draw and to make a regulator for 12 volts is nearly impossible for the amount of heat involved. I don't know if you mean cells or plates but in a cell there is usually an odd number of plates in Pb-acid cells and they are connected in series with 2 or three other cells to make 6 or 8 volt batteries for most EV's. Some EV's use 12 volt floor scrubber 12 volt batteries though rare. David is absolutely correct in a cell being in its own electrolyte and a cell can get out out whack. For Pb - acid it usually goes reverse and makes massive H2 gas and gets rather warm the cell of the battery swells and massive failure is imminent.
I have found out if you drive to less than 50% DOD the battery pack will be nearly "perfectly" balanced if battery pack was new to begin with and same run number and date code. But run them down and water some and not all equally and the ones that need more water will eventually croak first.


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