Rough Survey / Who Switched To AGM Last 12 months? HAPPY?

12 years on Lifelines, no holey t-shirts, zero corrosion in the battery compartment, fast charging. Works for me.

Probably could have gotten another couple of years out of them but there was some corrosion showing up around the posts.

Gdetrailer wrote:
Yes, there are some "good" points like you have mentioned, the problem is the bad points that folks gloss over, like..

LESS Ahr for the same PHYSICAL SIZE (IE takes MORE AGM batteries to equal Flooded Lead Acid).

DIFFERENT charging voltage profiles than Flooded Lead Acid..

Overcharging to the point of the VENTING WILL RESULT IN A EXPENSIVE DOOR STOP!

MUCH HIGHER COST PER Ahr!

If you are OK with spending more to get less Ahr capacity go ahead and do it.. Personally I am not OK with spending more to get less capacity..

Well .... my RV's 12 volt Group 31 deep cycle AGM batteries:

- Contain 115 amp-hours each. Another competitive Group 31 AGM brand even supply 125 amp-hours each. Not bad as compared to about the same group size and/or footprint in wet deep cycle RV batteries - 6 volt or 12 volt.

- Have over the years been charged and maintained almost exclusively by ONLY the stock 13.8 volt fixed voltage converter in the RV and the stock 130 amp Ford alternator under the hood. This is a very simple and bland charging and maintenance regimen, that in fact can easily ruin some wet deep cycle RV batteries, some of the time.

- Using the above charging and maintenance procedures, my AGM batteries have never dryed out ("vented") over time that I know of ... nor have their sides bulged out from getting close to venting.

- I shop for RV batteries by cost per amp-hour over battery lifetime plus my charges for battery messing hours over my lifetime.

My RV AGM batteries just sit there and do their thing year after year - but I do dust them off once a year. The 1st set of two went about eight years before I replaced them just in case (still working well AFAIK), and the 2nd set are into their 3rd year (FWIW, their warranty is 5 years).

My RV batteries shouldn't take up any of my time - just like my flashlight batteries don't take up any of my time. ;)

Gdetrailer wrote:

boshog wrote:

theoldwizard1 wrote:
I'll never understand why people are so "fire up" about AGM batteries. Unless the battery is mounted somewhere that it might tip over or in such a terrible location that serving a flooded cell battery is nearly impossible, it just does nor seem like it is worth ANY extra cost.

Here are my likes of AGM, lower parasitic loss, can tolerate deep cycling, much faster recharge time, and twice the service life. I'll fess up, this is what I'm told and don't have a long experience with them. My 2015 RAM Cummins came with a set of AGM batteries. Time will tell if my loyalty is misguided.

Yes, there are some "good" points like you have mentioned, the problem is the bad points that folks gloss over, like..

LESS Ahr for the same PHYSICAL SIZE (IE takes MORE AGM batteries to equal Flooded Lead Acid).

DIFFERENT charging voltage profiles than Flooded Lead Acid..

Overcharging to the point of the VENTING WILL RESULT IN A EXPENSIVE DOOR STOP!

MUCH HIGHER COST PER Ahr!

If you are OK with spending more to get less Ahr capacity go ahead and do it.. Personally I am not OK with spending more to get less capacity..

Carry on.

I use inteligent charger that automaticaly shuts off when AGM is fully charged,so no problems there..
I have battery inside my TC so no venting needed is a big plus..
Also leaving it there all winter without heat costs no harm,,I have solar panel charging continously so it never freezes,
Another plus is I dont have to worry about spills of acidic battery fluid..
Those pros outweigh all disadvantages it may have,,use Fulriver btw very reliable

Plug in the coach and let the converter voltage settle down. Then you must must must check voltage at the battery terminals with everything inside shut off except the converter.

Is the voltage higher than 13.6 volts? Tennessee can get mighty warm in the summer.

Take this one step at a time. Do the voltage check and then come back and post it on this thread :)

ken56 wrote:
Just bought an AGM for a replacement to my original (Exide group 24 flooded cell) battery. My unit did not come with a batt. isolation switch and it was always plugged in at home and I watched the water closely. It lasted 4 yrs 3 months. New battery is a Duracell AGM group 31, a bit taller than the old one but still fit in the box. Should I still install a cutoff switch for this batt? Like a lot of people I am not schooled in battery upkeep and care.

If you are plugged in you do not want to cut off the battery. The rig's converter maintains the battery ("Floats" it). If you are not plugged in so the battery is sitting there with a small draw on it from "parasitic loads" like the LP alarm and radio memory then, yes, you could use a cut-off. (Often with rigs, the installed "battery disconnect switch" still leaves some things drawing from the battery like the LP alarm and radio memory. You need to install your own at the battery to completely cut it off. Just as easy? To just take the wires off.

BTW AGMs can sit a long time completely disconnected (wires off) compared with Flooded batteries and not self-discharge so much.

So it is all down to HOW LONG you would be leaving them "cut- off."

Just bought an AGM for a replacement to my original (Exide group 24 flooded cell) battery. My unit did not come with a batt. isolation switch and it was always plugged in at home and I watched the water closely. It lasted 4 yrs 3 months. New battery is a Duracell AGM group 31, a bit taller than the old one but still fit in the box. Should I still install a cutoff switch for this batt? Like a lot of people I am not schooled in battery upkeep and care.

Two models I have confidence contain plates thicker than .080". Telecomm and Concorde Lifeline. But the Lifeline laughs at a C5 charge rate. The 31 accepts 105 amps at 14.4 volts @ 25c. The Fullriver and Deka seem to be neck-and-neck competitors.

I should have mentioned, I removed the sliding tray so I could fit the maximum sized AGM batteries. Without a tray, maintenance would be all but impossible.

I recently posted a question about AGM longevity. Viewers suggested I do a load test. From what I can tell my 7 year old AGM batteries function like new. My only maintenance is to open the compartment about once a year and see that everything looks OK.

I like the no maintenance features and long life.

I am surprised that no one has mentioned that with AGM's you do not get any corrosion in the battery compartment!