‘Winterizing’ the Batteries

Well, I don’t really winterize batteries, per se.  More like pull ’em to keep on a 3-stage charger while not in use.  Depending on the type, size, and manufacturer, batteries can be a fairly pricey investment.  Both proper use and maintenance are going to directly affect maximizing usable life.  There’s some serious science in battery use and maintenance, and I’m not going to pretend to be an expert.  I’m just sharing my method for maintaining the batts off-season.  There’s excellent information on deep-cycles found here.

I typically winterize in October (hopefully before any extended freezes), and part of that procedure is pulling the (2) batteries, and maintaining them on a Guest 3-stage charger, until Spring, when they go back in the ‘Stream.

Guest 3-stage charger Model 16202
Guest 3-stage charger Model 16202

Information on this model found at the ‘Guest’ website here

Despite my careful use and maintenance, the (2) OEM ‘deep-cycle’ Interstate batteries that came with our factory new Airstream lasted only 26 months- which is really poor.  I’ve seen campers routinely get 6 or 7 years out of their deep cycle batts.  Yeah, I know, Interstate offers a ‘warranty’; good luck with that.

Interstate SRM-24
OEM Interstate SRM-24. Bit the dust.
Specifications from the Interstate website
Specifications from the Interstate website

I’m sure the Airstream Parallax 7445, single stage converter/charger, doesn’t help, but it’s only charging for two weeks at a time (when camping), max.  I don’t think that’s enough time to damage a true deep-cycle.

Another thing I discovered, with the help of the Trimetric 2020 battery minder, the electric/hydraulic actuator is a huge power hog when braking.  Between that and running the furnace while underway (for winter camping), it was too taxing for the group 24’s capacity.  It’s possible I pushed the DOD well past 50% on several occasions; a combination of heavy current draw and the meager charge coming from the Suburban.   The only practical solutions for this would be either:

  1. upgrade the charge line (with some heavy welding cable) on the Suburban, from the alternator back to the 7-way.  This would provide more than the 6-8A I currently get.
  2. install a PV system on the Airstream.  Depending on the amount of panel (and daylight conditions), this could provide significant in-transit charging.

Option ‘2’ would need to include AGM battery upgrade, making the whole-nine-yards a very pricey investment.  Maybe Algore might subsidize the solar panel market with some of the hundreds of millions he made on his CurrenTV sale to Aljezeera?  In the meantime, an upgrade to a pair of Group-31’s helped maintain state of charge, considerably- and I paid for them without any taxpayer funded money.  Largest capacity I could find that would fit through the battery door were these (and very reasonably priced):

Aqua-Edge Group-31 battery
Aqua-Edge Group-31 battery

Only real drawback with this upgrade is the extra 30lbs of weight at the tongue… I know, doesn’t sound like much, but when I’m typically pushing 1300lbs, every pound makes a difference.

Getting installed on the Guest
‘Winterized’ on the Guest

So far, so good.  It’s been two years, as of this post, with these ‘Aqua Edge’ units, and they’re still going strong.

See you down the road!

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