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Dead battery, reversed polarity?

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Dead battery, reversed polarity? #1
Trevor Truitt Clarkston, WA, USA Sign in to contact	Topic Creator (OP) Jun 2, 2007 09:33 PM Joined 18 years ago 58 Posts

I took the battery out of the 68b I acquired this week and was attempting to charge it.

Two battery chargers gave me an error message, so I checked it with a voltmeter and the poles (neg and pos) are reversed?

I assume this is normal when a battery goes t/u, but I'd never heard of it before.

I was curious about the physics of it, chemical change in the battery, physical short inside or what. Anybody know?

Thanks,

Trevor Truitt

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Re: Dead battery, reversed polarity? #2
ingoldsb Terry Ingoldsby Calgary, AB, Canada Sign in to contact 1971 MG MGB	Jun 2, 2007 09:44 PM Top Contributor Joined 22 years ago 22,389 Posts

Was the battery ever charged backwards?

Terry Ingoldsby
terry.ingoldsby@DCExperts.com

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Re: Dead battery, reversed polarity? #3
Wray Wray Lemke ., SC, USA Sign in to contact 1956 MG MGA 1958 MG Magnette ZB Varitone 1973 MG MGB 1974 MG MGB GT & more	Jun 2, 2007 09:52 PM Top Contributor Joined 24 years ago 18,143 Posts

Sure. It's called cell reversal. When the battery charge gets down below a critical point one of the cells (usually a weaker one) can actually reverse polarity, the other cells will now try to charged the reversed cell.

I've seen somewhere that it can be cured by fully discharging the battery and then charging it back up at the correct polarity but usually the battery is toast after this happens.

But startin' Monday there'll be no debate
I'll start readin' my Bible, rise early, work late,
Recycle, stay sober, choose love over hate
Startin' Monday

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