AGM batteries...do you like them?

[slackercruster]

Been using lead acid. I had read the AGM catches fire once in a while. Is this only when charging or can it catch fire when not charging or being used.

What is your experience with AGM batteries?

Thanks!

[D&J]

Never heard of AGM batteries catching fire but lithium yes. We are on are second set of AGM Optima Blue tops, the first set lasted 13 years and this set is on their 7th year.

Denny

[oldjohnt]

Slack, for nearly forty years I used one to four wet flooded lead acid in RV's, later years they were Deep Cycle often Trojan brand which worked fine HOWEVER (A) when I upgraded to AGM I liked them MUCH better as I didn't have to worry with checking and adding water and they charged a bit faster NEVER had any problems. HOWEVER (B) later I upgraded to Lithium LiFePo4 and love them even more...

I think you will like AGM better then wet flooded, but its YOUR choice. PS I have two Renogy 12 Volt 200 Amp Hour Group size 4D AGM's for sale used maybe 2+ years, they weight 129 Lbs each the wife had a hard time loading them in the RV lol

PS I recommend use of a 3 Stage Regulated Smart Charger suited for AGM...

John T

[Chalkie]

At one point I did a lot of off roading one roads that had been scraped out of the mountains 100 years or more ago. To put it mildly, they were very rough. I got tired of constantly cleaning up the acid that made its way out of the batteries, a little can cause a lot of corrosion, so I switched over to AGM batteries. Yes, they are more expensive but they offer so much in versatility, they don't leak anything even upside down. Better yet, for me, they recharged faster and were far less susceptible to cold damage, as the ATVs were just kept outside the cabin and Colorado winters can be really cold at 9000'+ elevation. 

[Customer1]

AGM batteries are lead acid batteries, the difference is the acid is absorbed into a fiberglass mat between the lead plates rather than liquid like in a flooded battery. They don't catch fire and using them is nearly the same as flooded except you don't add water to AGM batteries.

[oldjohnt]

2 hours ago, Customer1 said:

AGM batteries are lead acid batteries, the difference is the acid is absorbed into a fiberglass mat between the lead plates rather than liquid like in a flooded battery.

EXACTLY (Absorbed Glass Mat AGM) I had good luck when I used them !!!!!!! 

 John T

 

[palmeris]

Unlike flooded lead acid,  AGM batteries are sealed 

[oldjohnt]

1 hour ago, palmeris said:

Unlike flooded lead acid,  AGM batteries are sealed 

Yep and in addition, ..."AGM batteries are a variant of Sealed VRLA batteries, just a more advanced design...".

Here's more for those interested: I liked them but since upgraded to LiFePo4..

5 Battery Types Explained - Sealed, AGM, Gel | BatteryStuff

John T

 

[slackercruster]

Thanks for all the replies!

[Lou Schneider]

One more opinion - I'd go Lithium instead of AGM.  Prices have really dropped on lithium batteries, you can get lithium for just a little more than comparable AGMs and they have many advantages over any lead acid battery.  Besides much longer life, lithiums don't fade out as they discharge so you don't have to worry about the furnace blower slowing down and not tripping the airflow switch in the middle of the night.  You can use 100% of their rated capacity without damage.  Which means for every usable amp-hour lithium is often less expensive than AGM or even some conventional flooded lead acid batteries.

Lithium's only drawbacks are they need slightly higher voltage to charge to 100% and you can't charge them if their internal temperature falls below freezing (32F).  They'll produce power down to -20F or so but they'll be damaged if you try to charge them when they're cold.   Most lithium  batteries now include some kind of cold charging protection, either refusing to charge if they're too cold or having internal heating pads that will warm them up.  But a few don't.  Plug and play LiFePO4 batteries are safe, the ones that catch fire either use older chemistry or are massively larger in size.

Edited August 11, 2023 by Lou Schneider

[oldjohnt]

13 hours ago, Lou Schneider said:

One more opinion - I'd go Lithium instead of AGM.

FWIW   X2 and Amen, good explanation..

 Way back when I upgraded from wet flooded lead acid to AGM so I didn't have to worry with adding water PLUS they charged a bit faster. Next in my journey I upgraded to LiFePo4 as they are much lighter, charge faster, you can discharge them deeper, and they don't experience as much voltage sag as their SOC decreases. HOWEVER a few years back YES they were more expensive (up front) but since prices have fallen and there are a ton of good quality manufacturers. They also require a charger or solar charge controller suitable for Lithium which is another expense if you upgrade.

 Bottom line if upgrading from wet flooded lead acid,,,,,,,,,,,,, you boondock often,,,,,,,,,, are an at least moderate energy user,,,,,,,,,,,,,,,plan to use the rig some years,,,,,,,,, your budget allows,,,,,,,,,, YES LITHIUM IS ANOTHER OPTION but it depends on a persons needs, RV lifestyle and budget NO RIGHT OR WRONG ANSWER 

 John T  I liked my AGM's but overall I like my Lithiums better...