Flooded,AGM or Gel deep cycle batteries 12volt

Vulcan Rider wrote:

ron.dittmer wrote:
It has been my experience for long term storage to disconnect all batteries rather than having the rig plugged in. I also disconnect the chassis battery.

Regardless of the type of batteries you have (let's NOT get into Lithium please), it is best to have them fully charged during storage. If the storage is longer than 90 days or so, that means "topping them up" every so often. I do it once a month.....when I move the rig about 18 inches to help prevent permanent tire flat spots.

With them disconnected off season, I top mine off about every third month (when I remember). I figure they sit on the shelf in the stores for at least 90 days before getting sold.

Vulcan Rider wrote:

klutchdust wrote:
Coach is on ground power when stored at my home.

While that sounds like a good idea.....and is in most cases.....the inverter/converter continuously charging the batteries is NOT a good idea with some of the OEM "basic" controllers. Tends to overcharge and "boil" off the water.

I use the coach as my hideaway and napping spot. The air conditioner running is a dead giveaway though. Not a problem to drop the negative cable off as the batteries are easily accessible.

As far as the onboard system charging AGM's I need to check on what system the coach has and the output. I agree with another poster, I may just put two 6 volt Trojan's in there and call it

a day, it would be more AH's than I presently have and using those types of batteries on my TT I got 6 years of service out of them with no issues.

Dragonfly wrote:

My alternator will top them off when driving but it takes too long.

In my opinion, you are making a LOT of assumptions here and you need to do some actual testing to see what your situation really IS.

If you are going to get an outboard charger and will be in a position to USE it between between drain-downs......I don't see what your concern is with the charging times from the "truck" or the controller.

I don't know your exact situation but try to be practical and not emotional. I don't remember hearing of ANYBODY in any application being sorry that they upgraded to AGM batteries.

ron.dittmer wrote:
It has been my experience for long term storage to disconnect all batteries rather than having the rig plugged in. I also disconnect the chassis battery.

Regardless of the type of batteries you have (let's NOT get into Lithium please), it is best to have them fully charged during storage. If the storage is longer than 90 days or so, that means "topping them up" every so often. I do it once a month.....when I move the rig about 18 inches to help prevent permanent tire flat spots.

RambleOnNW wrote:
I'll repeat, get a smart multistage charger. With the setup I have now, mentioned above, the AGMs quickly get charged (in 3 hrs) to 90% at 14.4V in boost mode, then the charger switches to 13.6V to charge the rest of the way to 100%. After that the charger switches to a float charge of 13.2V. There is a monitor LED on the Charge Wizard Pendant that shows the charge mode and I can see it does make it to the float mode indicating the charge is 100%.

Since the AGMs charge to 12.9V, the Battery Monitor that is part of the panel with the other monitors (fresh water, gray, black tank levels) indicated Full for many hours after fully charging while dry camping.

Without the smart charging the charger originally put out a straight 13.6V.

----------
Thanks for this. It is basically the information I have been seeking and will take me a long way towards getting my system complete.

klutchdust wrote:
Coach is on ground power when stored at my home.

While that sounds like a good idea.....and is in most cases.....the inverter/converter continuously charging the batteries is NOT a good idea with some of the OEM "basic" controllers. Tends to overcharge and "boil" off the water.

My reply above with the picture, does as you advise. It's not built into the rig but it does accomplish the same results. The charger has a setting for proper AGM charging.

I'll repeat, get a smart multistage power converter/charger. With the setup I have now, mentioned above, the AGMs quickly get charged (in 3 hrs) to 90% at 14.4V in boost mode, then the converter/charger switches to 13.6V to charge the rest of the way to 100%. After that the converter switches to a float charge of 13.2V. There is a monitor LED on the Charge Wizard Pendant that shows the charge mode and I can see it does make it to the float mode indicating the charge is 100%.

Since the AGMs charge to 12.9V, the Battery Monitor that is part of the panel with the other monitors (fresh water, gray, black tank levels) indicated Full for many hours after fully charging while dry camping.

Without the smart charging the converter/charger originally put out a straight 13.6V.

With 13.6V you need to unplug the RV and stop charging the batteries once they are fully charged. With a 13.2V float voltage there is no need to stop charging the batteries.

Vulcan Rider wrote:

Bottom line: A really LOT of people worry about this when there really is no need. Even if it does only charge to 95%, you still are going to get most of the advantages of AGM...

----------
I have just begun deciding on battery options but here is what I do and do not know (yet).

I need every bit of extra storage and amp hours of an AGM since I rarely plug in. I don't think I am getting 95% out of the built in charger when plugged in or on generator. It is lower, perhaps 75-80% (although I haven't tested it yet and am estimating from the idiot light tester on the wall). Apparently most built in converter chargers will not top off an AGM for a LONG time, if ever. A not too expensive supplementary charger will do the trick.

My alternator will top them off when driving but it takes too long. You can upgrade the alternator but I think there is a way to adjust the output to the coach batteries to speed up the charging process a bit. I will post that when I get the details. It takes a lot of juice to cram that extra load into an AGM both via the alternator and the charger.

I am no tech geek and I am not seeking 100%. I would be happy with 95%. I just need every bit of charge I can get the way I travel. Also, deep cycle batteries are built to be discharged and charged over and over but, if you drain them too low, too often and, if you don't keep them topped off in between, the shorter they will last.

Good AGMs are very expensive (there are lesser quality AGMs for less though). I am hard on batteries. Sometime I think it might be better to get some cheaper open cell and run them to death. I could buy three sets for the price of the AGMs. But, my batteries are under the floor and it would VERY difficult to monitor water levels.

If you don't need the extra storage and life out of an AGM battery don't invest in them. If you do need it you may need a supplementary charger and a look at your alternator to get their full benefit and life span.

klutchdust wrote:
Coach is on ground power when stored at my home.

It has been my experience for long term storage to disconnect all batteries rather than having the rig plugged in. I also disconnect the chassis battery.