AGM vs. Classic Wet Battery?

[aztex]

Hi,

I requested my new RV be upgraded to two new AGM batteries but forgot to push real hard in negotiations. I requested them as part of the deal but on second thought can't recall the salesman's exact response other than "fresh batteries". It has classic Interstate 12v wet batteries now. Is there an advantage one kind over another? I've been lead to believe the AGM are superior in every way.

I have a feeling when I get to PDI there will be the same old Interstates... Is that a deal breaker or if they stand firm should I just take the deal and move on or buy the AGMs?

 

Thanks!

 

[sandsys]

I bought AGMs because you never have to water them. I wanted to minimize maintenance tasks. Whether or not this is a deal breaker for you only you can decide.

Linda Sand

[Ray,IN]

I alot an hour once a month to check the  solution level in my wet-cell batteries. The only thing that makes checking solution level difficult is battery cable placement over cell caps. Since I install my batteries, I position cables so every cap may be removed without unhooking a cable.

If there is head-room above wet-cell batteries, an automatic watering system may be installed. This product reduces watering time by at least 50%. Since I'm retired, time consumed is not a concern or I would purchase one.

Edited March 14, 2020 by Ray,IN

[sandsys]

Another benefit to AGMs is you can put them in inaccessible places since you don't need to deal with them until they die. Plus, they don't have to be isolated so you can put them in living areas--even under your bed if that's where you have the best space. In case you can't tell, I am a big fan of AGM batteries. Although if I was building new now I'd be considering Lithium batteries because you can run them to a much lower charge level without damaging them. To me, which battery is right for you is all about how YOU perceive the cost/benefit ratio.

Linda

[Dapperdan]

AGMs are great, I "almost" replaced my wet cell 6 volts with AGMs.  Sam's Club had a sale last spring on 6 volt golf cart batteries, I was able to buy two wet-cell batteries for less than what ONE AGM cost.  I paid (I think) $69 a piece for them.  There are great advantages to AGMs as stated above but for me I don't mind checking the water level in my batteries every few months and I don't worry about the off gassing.  

You have to go with what makes YOU happy and fits in YOUR budget, simple as that.

 

Dan

[Kirk W]

The main advantage of AGM batteries is the lack of maintenance. The disadvantage is the cost. As to the issue of deal breaking, it is much the same as the hitch that you wanted. How important is it to you and what cost to make the change yourself? You might be able to work something to change them for you at a reduced cost. 

[Sehc]

Interstate batteries are not the best to begin. Agm usually do not offer the amp-hours available with deep cycle wet cell. Comparing foot print.

[oldjohnt]

I upgraded from wet flooded lead acid to AGM AND AM VERY SATISFIED. I don't have to worry with checking and adding water, believe they can accept a faster/higher charge, HOWEVER their cost was a bit higher. I see no reason why Id ever go back to wet FLA.  Now if  I (who does a lot of dry camping) were younger and knew Id camp say 7 to 10 more years and/or keep the same RV that long, I'd  choose Lithium, that's up and coming technology for long term dry campers.

 If you're looking at AGM consider the single 12 Volt Deep Cycle units which may be in the 100 Amp Hour range or the Frame size 4D 200 Amp Hour units if you have the space. My 208 Amp Hour 12 Volt Frame Size 4D batteries weight 129 lbs each grrrrrrrrrrrr. I looked at Full River, Lifeline, Trojan and Renogy and there are several other good brands out there.

 Your money, your space requirements, your budget, your choice

John T

[Pat & Pete]

44 minutes ago, oldjohnt said:

I upgraded from wet flooded lead acid to AGM AND AM VERY SATISFIED. I don't have to worry with checking and adding water, believe they can accept a faster/higher charge, HOWEVER their cost was a bit higher. I see no reason why Id ever go back to wet FLA.  Now if  I (who does a lot of dry camping) were younger and knew Id camp say 7 to 10 more years and/or keep the same RV that long, I'd  choose Lithium, that's up and coming technology for long term dry campers.

 

We did the same about 9 years back . 

I tried a wet cell a year and a half ago , because of cost and availability . Mistake . I gave it plenty of time to prove itself . 

5 months later I brought it back and made work of buying a Cat brand AGM . Not so much as a hiccup since . 

[Sehc]

Cat battery manufactured by East Penn. Good stuff.

 

[Pat & Pete]

55 minutes ago, Sehc said:

Cat battery manufactured by East Penn. Good stuff.

 

Very good stuff , in my honest opinion . 

The Cat battery that finally gave up was 12 years old from the stamped manufacturer date .

I bought it second hand . The company that it came from used batteries for 3-4 years and then replaced them .

Edited March 15, 2020 by Pat & Pete

[nscaler2]

One other reason for AGMs is that they degenerate more slowly than wet cells do.  For us the advantage is that we leave our rv in storage for approximately 6 months out of the year.  I disconnect the batteries so no parasitic sources can drain the batteries.  Even after 6 months they have enough power left to operate the hydraulics for the landing jacks and get it connected to my truck.  Where I store it, there is no way to keep the batteries charged.

[Ray,IN]

On 4/26/2020 at 8:06 PM, nscaler2 said:

One other reason for AGMs is that they degenerate more slowly than wet cells do.  For us the advantage is that we leave our rv in storage for approximately 6 months out of the year.  I disconnect the batteries so no parasitic sources can drain the batteries.  Even after 6 months they have enough power left to operate the hydraulics for the landing jacks and get it connected to my truck.  Where I store it, there is no way to keep the batteries charged.

Our 40' 5er was stored outside, it had wet-cell batteries which always were at least 50% SOC after 6 months of unattended storage. It has more to do with eliminating phantom loads than battery type.

My farm tractor sat parked for a year, and started as soon as the carb filled with gas.

[fpmtngal]

My trailer has access problems for half of the cells, so very difficult to check.  It got a lot better when I bought a battery watering system - there was enough room for the caps.  That worked much better, though I did end up changing to AGM when I replaced my single Group 29 with two Group 31 batteries (biggest batteries that will fit in the space for them).

Just my opinion, but I wouldn’t consider having flooded batteries a deal-breaker.  I’d just buy a watering system for them, and that would be cheaper than replacing them with AGM batteries.  I’d be more concerned with the Ah capability of the battery.

[Chalkie]

On 3/14/2020 at 8:28 AM, Sehc said:

Interstate batteries are not the best to begin.

Just to point out that depending on Group Size, Consumer Reports would disagree with you as Interstate batteries come in at the top or near the top of the list in a number of sizes. 

It is definitely worth researching any battery you intend to purchase to make sure you are getting the most for your money.

[Ray,IN]

On 4/28/2020 at 11:21 AM, Chalkie said:

It is definitely worth researching any battery you intend to purchase to make sure you are getting the most for your money.

Yup, that's why I bought batteries made by Deka Penn at Sams Club.

[sushidog]

Now that you've heard all the virtues of AGM batteries you have to ask yourself "If I could have twice the battery capacity for the same price would it be worth it to go to flooded lead acid batteries?"  But if you thinking goes something like, "I can afford to go with the best, so I want low maintenance, super low discharge rate so I can store it all winter without checking and batteries that be used on their side, don't gas at all, charge in half the time of either FLAs or AGMs, produce lots of power in a small footprint at 1/3rd the weight, then you want lithiums. I'd look at Battle Borns as they are a drop in and don't need a special converter. AGMs are just low maintenance lead acid batteries at 3 times the price. Lithiums are on a whole nother level, but at 10 times the price. But they last 5 times as long, so at cost per KWH hr produced they are much cheaper than AGMs and almost as cheap as FLAs.  Their up front cost will give you sticker shock though.  

 

[nscaler2]

On 4/27/2020 at 10:18 PM, Ray,IN said:

Our 40' 5er was stored outside, it had wet-cell batteries which always were at least 50% SOC after 6 months of unattended storage. It has more to do with eliminating phantom loads than battery type.

My farm tractor sat parked for a year, and started as soon as the carb filled with gas.

It is a fact that AGM batteries degenerate more slowly the flooded ones.  They can also be discharged to deeper without doing damage to the battery.  Here is a link to all you would like to know about AGMs.  https://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

[Ray,IN]

1 hour ago, nscaler2 said:

It is a fact that AGM batteries degenerate more slowly the flooded ones.  They can also be discharged to deeper without doing damage to the battery.  Here is a link to all you would like to know about AGMs.  https://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

I know all that, I was answering the question. I choose not to spend the money for AGM's again. In the end buying AGM batteries cost me more than 3X the FLA batteries. I needed to add water 2x a year, even while the MH was constantly on shore power. My preference.

[Pat & Pete]

About all I know about AGM CAT brand batteries is that they last at least twice as long as FLA units AND , I never have to touch them . That's my preference .

[Ray,IN]

Pete, that's what this nation is all about, freedom of choice is just one. I'm happy we agree.

[Randyretired]

The FLA batteries from Sam's Club have been lasting about 6 or 7 years in our setup.  We have 6 of them.  The AGM batteries I found were about 3 times.  I already have a watering system so that only takes a minute or maybe 2.  I keep a jug of distilled water in the battery compartment.  For me the AGM's would need to last about 20 years.  That is likely beyond my RVing and maybe more but I can see where some would like the AGM's and maybe lithium batteries. Choice is good.

[oldjohnt]

DITTO Gotta love CHOICE. One reason I upgraded from FLA to AGM was not having to check and add water grrrrrrrrrrrr. Besides, I got a great deal when I bought my three 208 Amp Hour 12 Volt units (not much more expensive then buying FLA) and I didn't have to series two 6 volters together. I'm never going back..

 HOWEVER If I was younger and knew Id be RVing several more years especially with the same RV and increasing the pay back economics ID GO LITHIUM in a heartbeat.

 CHOICE is what its all about regardless of a whole sort of factors, be they right or wrong lol

John T   Live and still pretty much quarantined in Indiana.

[Pat & Pete]

Right guys . Choices . It'd be a pretty mundane world if we didn't have choices , for sure .

Just a note : Our last AGM finally gave it up after 12 years of pretty much constant use . The first 4 years of it's life were under industrial conditions . The last 8 were a cake walk keeping our Monaco well powered . 

I had tried an FLA when that^ AGM gave out . It lasted a couple months before weird things happened . As soon as possible , it was replaced by our current , problem free , Cat brand battery . Oh , the Cat brand only cost about 1/3 more than the FLA .

Edited May 3, 2020 by Pat & Pete

[oldjohnt]

Yo Pat, I bought some 208 Amp Hour 12 Volt AGM's, Frame Size 4D, 129 lbs each, for $247 picked up at Walmart and they loaded them in my car HOWEVER  a couple weeks later about every vendor including Walmart jumped them up to near $400. Had mine all been that much I might not have upgraded but glad now I did. Still I cant fault my previous Trojan T-105's for their service. REGARDLESS of battery technology if you use and maintain them with great care, avoid very many discharges at even 30% let alone 50% capacity, pretty much with Solar and/or Smart Charging capacity keep them near float levels most of their lives (so as to NOT use up a limited number of Life Cycles)  YOU WILL GET EXTENDED LIFE...….However if you're daily discharging them near 50% and consuming precious number of finite Life Cycles THEY WONT LAST AS LONG 

Take care n be safe yall

 

John T