David Beierl gave me a great response to a different question that
applies here, I believe:

"Second, if you really want to pull 150-watt loads for any length of
time, go do some studying at http://www.amplepower.com/ and do some
studying.  It's perfectly possible to use batteries efficiently, but
you're not going to do it with an automotive charging system.  At a
minimum you'll need a deep-cycle battery; and either a three-stage
"smart" regulator like the Ample Power Next-Step device (their cheapest
at $300; I've been running one on Scamp for 2-3 years now and it
performs exactly as advertised, using a 35-amp alternator charging
roughly 300 amp-hours of capacity in two banks) or a manual regulator
that's cheap, but you have to watch it like a hawk."

I'd check out that link as there's a good primer on batteries and why
deep-cycle is the way to go.  Note that I think a lot of what's said on
Ample Power is complete overkill, but their target market is RVs with
battery banks, not Westies and single small battery.

FWIW,
MB

David Devere wrote:
> Can anyone convince me why, besides the obvious reason of better charge life, I should buy an Optima battery vs. using an old Die Hard for a second aux. battery in my van?  What are the problems with using a conventional battery?  I understand the Optima is safer because it is sealed but do I really need to be that worried?
>
> Thanks -Dave
> Duluth MN Where the temp tomorrow is going to be a sultry 40F.  Warm enough finally to work on the Van!
> 87 Syncro Westy with 177K

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_______________________________________________________________________
Mark Belanger - belanger@fluid.com