Tim, The ideal battery that will not boil off electrolyte is a VRSLA (Valve Regulated Sealed Lead Acid) unit with AGM (Absorptive Glass Mat) design. Provided that the charging voltage remains within the tolerances specified by the battery manufacturer, it will never run dry. That's because the hydrogen and oxygen generated during charging are recombined by catalysts within the battery, so that pressure cannot build up and vent. Such batteries are usually identified as "non-spillable" since the electrolyte is in gelled form rather than liquid form.
One question: Are you using a different PL tone on the portable repeater, so that you don't key up both machines when you're in a coverage overlap area? 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of tahrens301 Sent: Friday, January 29, 2010 4:00 PM To: [email protected] Subject: [Repeater-Builder] Battery system for portable repeater (non solar) Now that the actual repeater is complete, I am looking for some suggestions about how to power it. The repeater and +12v power source will be stored in our rescue truck. The idea behind this is to be able to set it up on top of a hill so that we can have communications with personnel on the other side. (although we have a pretty good 'main' repeater, there are many areas of our district where we don't have handheld coverage). There won't be any charging while at the operating site - a fresh battery will be brought in as required, or it could possibly be powered by a vehicle. Ideally, I'd like to store the power source on the truck with a trickle charger to keep it ready to go, but I'm concerned about gas. Do the AGM style batteries outgas while charging? >From what I've read about backup power, the AGM is the most 'forgiving' for really deep cycling. Just not sure about leaving a trickle charger going all the time. (bad previous experiences) Thanks, Tim
