teotwaki
Excelsior!
(12-volt batteries supply useful energy only through a limited range -- from over 14 volts (when fully charged and unrested) down to 10.5 volts in use/under load (when lights dim, pumps groan and TV pictures get small). No 12-volt battery will remain at over 14 volts for more than seconds unless it's being charged. The lowest limit is 10.5 volts (used in testing) and obviously unsatisfactory in practical use. Experienced RVers try to use no more than 20% to 50% of the energy available in a battery before recharging. That means they never let resting voltage get below 12.5. They never use more than 50% before recharging (resting volts of 12.3) except in an emergency. They know that, if resting voltage ever reaches 12.1, they have deep-discharged one cycle and that a battery is good for only so many cycles (from as low as 20 in an automotive battery to 180 in a golf cart battery, with the typical RV/marine battery good for no more than 30).
Jim runs the battery down below 12.3 volts too many times then blame Optima Jim for personally handing out pink slips to factory workers that produced in a country racked by EPA laws governing the lead. A battery at 12.1 is deeply discharged and it can only do this a few times. Pulling them down to 10 and all bets are off as far as saving the battery. I get away with it but only sometimes and when I don't I pay. I think Jim needs to take better care not to discharge his batts and pay the other Jim for a new Optima after he promises to keep them above 12.3 volts.
How many times have I run the battery below 12.3 volts and how many times is "too many"? How many times do you run them down and is that too many?? I've openly posted photos and numbers for what OJ asked but don't use a broad brush to paint my battery usage as bad when you've posted no tests of your own. Feel free to educate me but don't make accusations, please.
Anyhow, "never letting resting voltage get below 12.5" brings about the whole discussion of how long it takes to replenish the Amp Hours drawn out of the Optima and how an alternator differs from an AC powered charger in the time it takes to do that. What I've seen so far is that it takes longer for the alternator than the AC powered charger. I've yet to try to document it because I don't have an easy way to measure and data capture the amperage flow at the battery terminals. I think I've got to build some heavy duty adaptors to get my Watts Up set up in line with the battery cables.
For the record, I never blamed OJ for the Denver pink slips. His employers handled that. Lots of companies still produce batteries in the US in compliance with EPA laws. Deka, US Batteries and so on. So exactly why are you defending Optima for laying off US workers?