[VAC] Optima Battery

[Rik & Susan Beeson <rik@xxxxxxxxxx>]

Sorry to be replying so late... I'm 'way behind reading the list.

Pete, you mention having a new Optima battery. Is that an AGM 
deep-cycle? If it is, the charge line from your tow rig will be 
overcharging it. AGM batteries are wonderful -- I have a 12-volt 
Concorde AGM for my  UPS -- but they are definitely not compatible with 
lead-acid batteries, such as the one in your tow vehicle. AGMs must have 
a lower maximum charge voltage,  according to everything I have read 
about them. I originally got the Concorde as a house battery for my 
Argosy motorhome, but then discovered that an AGM and a lead-acid 
battery cannot be used together and charged from the same source -- the 
engine generator. The voltage difference is not much -- .2-.3 volts -- 
but apparently it's enough to make a difference to the battery.

If someone else has definitive information about the mixing of AGM and 
lead-acid batteries, I stand ready to be corrected.

Best regards,

Rik