Yes, I know about deep-cycle batteries, but it should be fully =20 acceptable to discharge a standard (starter) automotive battery to =20 some level, and that's the level I'm trying to determine. The reason =20 for standard automotive batteries is that I have several. If I find =20 that I can safely use only say 25AH of a 50AH battery, then I can take =20 two, etc. Cheers, -Neil. Quoting Byron Jeff : > On Mon, Oct 14, 2013 at 05:18:14PM -0400, Neil wrote: > You are starting from a technology that is not appropriate for the > application. Deep Cycle batteries are designed to be deeply discharged > without damage. Starter batteries are designed for shallow discharge at a > high amp rate. Your application is exactly the opposite of that. > > I would suggest getting a pair of U1 deep cycle wheelchair batteries > such as these: > > http://www.apexbattery.com/12v-35-ah-u1-wheelchair-battery-replaces-33ah-= power-sonic-ps-12330.html > > It'll give you 70 AH total, no worries about deep discharge conditions, a= nd > as a Sealed battery, no worry about watering or spillage. > > I have a local shop in the Atlanta area that sells powerSonics used for $= 25 a > pop. They are my standard deep cycle battery. > > Hope this helps. > > BAJ > >> >> Cheers, >> -Neil. >> >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist > > -- > Byron A. Jeff > Chair: Department of Computer Science and Information Technology > College of Information and Mathematical Sciences > Clayton State University > http://faculty.clayton.edu/bjeff > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .