[RE-wrenches] trickle charger for 4 12V batteries

[Dana]

I have sealed 12 vdc batteries in 2 Bimmers. 
First winter - Left full time on a BMW smart charger over the winter killed both. My mechanic confirmed this was a bad idea.
Second winter - did a 24-30 hour tapered maintenance charge (same charger) every 5-8 weeks and they are still good shape after 5 years.


Dana Orzel                              Great Solar Works, Inc. 
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Idaho Contractor - # 028765         Idaho PV # 028374
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-----Original Message-----
From: RE-wrenches <re-wrenches-bounces at lists.re-wrenches.org> On Behalf Of Alex MeVay
Sent: Friday, October 18, 2019 2:04 PM
To: RE-wrenches <re-wrenches at lists.re-wrenches.org>
Subject: Re: [RE-wrenches] trickle charger for 4 12V batteries

Hi Dave,

I'm interested in others' experience here, but personally, I'd skip the charger.  If they are brought to full charge before storage and are in decent shape otherwise, they shouldn't have any trouble surviving winter storage.

I've seen many sealed batteries die an untimely death due to electrolyte loss from trickle chargers.  On the other side, I've many times stored stored vehicles for 3-8 months with batteries disconnected and no apparent ill effects (and enough charge remaining to start the car upon my return), save one battery that was already on the way out.  The ideal scenario, in my mind, would be to charge the batteries about once a month.

Alex MeVay

Blue Sky Energy * http://www.blueskyenergyinc.com Genasun * http://www.genasun.com _______________________________________________
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