Where to buy and what brand of AGM battery?

[tony.latham]

I would suggest staying away from a Duracell.

And thanks!

Tony

[tony.latham]

...here is what I saw at WM...

Gudmund:

I really appreciate you doing this footwork for me. I owe you.

According to the Battery University website (that appears to be independent of manufacturers or retailers), "The leading advantages of AGM are a charge that is up to five times faster than the flooded version, and the ability to deep cycle."

I assume that's true?

What I have found that within any given size of battery, the weight from one brand to another varies greatly. Those WM G24 batts weigh 46 pounds. The Universal Battery Group batt weighs 49. The VMAXTANK batt that was my preferred choice weighs 55. (On backorder status). Trojans weigh in at 54. (Those last two cost about $100 over the WM and UBG batts.)

I'm not a physicist but I'm sure the volume of lead in a battery matters and thus the weight of a battery must be significant for comparison purposes. I think that's true.

My goal with this purchase is to kick the can down the road for six or more years and then take a look at lithium batteries (or maybe a used flux capacitor) or whatever raises its head.

According to VMAX, at 50% discharge, they claim 900 cycles. UPG says it's dead after 550 cycles down to 50%. And that's the $100 difference. But, we use about 20 amps maximum a night. (CPAP). So at a 25% discharge, I should get 1200 cycles with the UPG and 1600 with the VMAX. (When's the new flux capacitor going to hit the market?)

For now, I'll kick this can over to tomorrow. I need to get back to my shop and finish the doors today.

Gudmund: Thanks again.

T

[gudmund]

the other thing that comes to mind would be W-M's Warranty and how it compares to the others?? These battery's have a = 5 year "FREE" replacement + a 2 year 'pro rated' on their 'AGM' batteries. Don't know how this compares, but would be something else to consider when doing the comparison between brands. I have never had any problem with the W-M ones I have purchased over the years. (in fact, I did just a few month back got feedback from the 'now' owner of my old 2000 Chev S-10) 'complaining' about the battery going bad in it - I had bought and installed it in Jan/08 when I got the PU - it was the best one W-M sold and came with a 9 year warranty - as if there had been an "implied warranty" on this PU being it is now 19 years old (I had been the second owner and he is now the 5th being he had gotten it from another co-worker or two after I had sold it to one in 2014). My comeback to him was = it's 2019 now - "10/11 years of battery life out a 9 year warrantee = "sounds" pretty good to me!!!" Guess, it's time for "you" to just buy a new battery!!!!! (somebody I 'had' to work with for 20+ years that was always complaining about everything)

please keep us updated on how well one of these batteries works out - I myself, will be needing one probably in the next year or two and the AGM version is what I have been looking at.

[tony.latham]

These battery's have a = 5 year "FREE" replacement + a 2 year 'pro rated' on their 'AGM' batteries.

That is huge and the fact that this country isn't short of Walmarts really helps.

Tony

[gudmund]

just got back from a 6500 miles round trip from Wash. to Minn. and -YES- Wal-Mart's were everywhere!! and yes, for the most part it was also my "road" $$BANK$$ of choice when in need of $cash$ - kind of the US 'Bank of Wal-Mart' - worked great at about $100 cash per visit + purchases....................... with a FREE over-nite stay or two along the way....

[RJ Howell]

[quote="tony.latham"][

According to the Battery University website (that appears to be independent of manufacturers or retailers), "The leading advantages of AGM are a charge that is up to five times faster than the flooded version, and the ability to deep cycle."

Agm's and Gels both work a bit better than LA's. LA's are more forgiving to operator error.. 5 times that of an LA.. doubt it..

I'm not a physicist but I'm sure the volume of lead in a battery matters and thus the weight of a battery must be significant for comparison purposes. I think that's true.

True! That's why we go to 6v's!

According to VMAX, at 50% discharge, they claim 900 cycles. UPG says it's dead after 550 cycles down to 50%. And that's the $100 difference.

12v'ers should not be brought down to 50%.. Like ever.. 70-75% max if you wish them to last


Most battery issues are operator error. That being said, if you want a low draw and last, go 6v's. That's what they are built for. You have the $$, go lithium. I'm on a pair of 230ah 6v's and love the system (LA's) especially for the dollar! That gives me up to 115ah before any issues, though I rarely go beyond 50ah (that's 3 days for me).
You decide what's best for you. I'm not a fan of 12v's, of any sort (except lithium).

[tony.latham]

I'm on a pair of 230ah 6v's and love the system ...

RJ:

Thanks for your thoughts. You must have more power needs than we do.

I don't need that many amps nor do I have room in the galley for two GC batteries. I don't want to fill up my tongue box with batts and I don't want to be hauling 140 pounds of lead. This new group 24 will nest behind my water jug.



Nice and tidy.

We'll use about 20 amps max per night or 25%.

Tony

[RJ Howell]

RJ:

Thanks for your thoughts. You must have more power needs than we do.

We'll use about 20 amps max per night or 25%.

Tony[/quote]

We're actually very close in usage. I do hear you about the weight! I just tend to camp in the woods, for days on end.. I do like the additional power to extend the stay.
I see Trojan makes a 12V AGM that has 75ah (C20 rating).

[tony.latham]

We're actually very close in usage. I do hear you about the weight! I just tend to camp in the woods, for days on end.

Exactly! In April we did a twenty-night trip.



In the past, we've kept the battery topped off with 80 watts of solar. This new build I've got cooking will have a 100-watt panel on the roof.

Tony

[RJ Howell]

Good setup!

Up here in the Nor'East, lucky if I can gain 3hrs on a full sun day! Way too many trees! If I went roof mount, I'd double my wattage. Yet that's up here!
I'm running 130w panel, it's big and hard to stow.. I will go smaller, but multiple. I really do like the flexible and costs are down to reasonable now. So many I talk to about them are as many that like & dis-like them.. Again, just by design, I'd go at least 1.5x...

Sounds like you have a good handle on things! Safe and happy travels my friend!

[tony.latham]

The problem with flexible panels is that most of them are made from PET. Two or three years and they go south.

The good ones are about double the cost and made from ETFE. I’m installing a Renogy that has a five year manufacturing warrant and a twenty-five year output warranty.

We too have trees in Idaho but shady camps are still few and far between.

Like our currently drop, I’ll be installing a 20- watt panel on the tongue box.

Stay shady,

Tony

[gudmund]

Tony - after re-reading all of the spec's of the 3 battery's I sent pictures of - I did notice something to bring to your attention-I miss-read some warranty info. Yes, all 3 are the same $$$, BUT the smallest one (the 24 that you are interested in) has a lesser/different warranty on it - it is a 3 year FREE replacement with 2 year pro-rated for a total of 5 years - the other two 'bigger' - more powerful battery's, are both 5 Year FREE replacements. Bigger ones - more power - same $$, better warranty's - go figure??? I will be stopping and checking the local NAPA store being when I was on my 'cross state travel' trip, I had stopped at one and did notice as I was leaving, they also had had the AGM's on their shelves - but did not have time to check them out (I do know that when I have looked at theirs before - theirs have always been made by Exide) and the $$'s I saw back on these AGM's, were around the $200 mark each. Will try and get a closer look at them and get pictures of them also. (one of the nice thing about not having to work any longer - I can just do whatever I want whenever!!! driving a 45+mpg puddle-jumper too-boot!!!! and it is $$$ for)

[tony.latham]

...theirs have always been made by Exide

I bumped into this Youtube about Exide batts. I'll pass on that. -But thanks again.

Tony

[gudmund]

no luck on the NAPA stores in my area today - neither had any AGM's in stock to look at nor any info about what was available. oh well.

[tony.latham]

no luck on the NAPA stores in my area today - neither had any AGM's in stock to look at nor any info about what was available. oh well.

Thanks for looking.

I pulled the trigger on a VMAX XTR34-75 12V 75Ah Group 34. It'll fit my space and should give me plenty of juice.

Ask me in six years how it's working...

Tony