Any experience with a Vmax battery?

[mep1811]

I found this battery. I'm thinking of this for a trailer battery

https://www.vmaxtanks.com/SLR125-12Volts-125AH-Deep-Cycle-Solar-AGM-Battery_p_38.html

https://www.amazon.com/dp/B004DR3II...colid=EBF93S2S94MK&psc=0&ref_=lv_ov_lig_dp_it

 

[dreadlocks]

I had one, was crap for a trailer and failed quickly into its 2nd season.. do your self a favor and get two cheap GC batteries, get twice the capacity for $100 less and the'll last longer and take more abuse.

AGM is for suckers and they got me.

 

[john61ct]

There are a half dozen excellent makers of AGM in the NA market, that's not one.

Quality FLA beats them all.

Don't buy big lead batts online.

 

[pdxfrogdog]

I've got that exact 125ah battery. Have had it for 4 years and it's been trouble free, I've actually been happy with it. It was purchased with $ warranty refunded from a diehard group 31 platinum (rebadged odyssey 2150) which was a bit of an ExPo forums darling for years. Top tier brands don't guarantee success, 2nd or 3rd tier don't guarantee failure. What top tier does usually is guarantee a solid warranty and customer service. That might be tougher with internet brands, but VMAX has been responsive to technical questions I've asked in the past. I've never sought a warranty claim. So, I'm not as negative as your two previous responses, but it is more of a roll of the dice. I'll agree with them that FLA is superior to AGM for most... AGM can be cranky (heh) about charging profile. It also might be tricky doing a warranty return on an internet battery that weighs over 70lbs. I've since retired this battery for LiFePO4, but that's a whole different conversation and price range. Good luck with the hunt for a solid battery!

 

[jacobconroy]

I have used that exact battery for two years. It's worked so far. Now that I'm thinking about increasing my ah I'm either going to get two more of them, or do what @dreadlocks says and buy two golf cart batteries.

If I go with golf cart batteries....I assume they need to be vented to the outside of the rig. Is that so?

 

[john61ct]

Only if you seal them up in the first place, or

normal living space ventilation is not enough, and you find occupant(s) getting bothered by any smells.

 

[john61ct]

There are a half dozen excellent makers of AGM in the NA market

If you are willing to spend more up front for sealed, in NA market, start with Odyssey, then Lifeline or Northstar.

GEL does last a lot longer but much more finicky wrt charge profile, even more so than AGM, very sensitive to overcharge.

But FLA is most robust, stands up to mistakes better, lasts longer, and cheaper in both per-Ah up front, and of course annualized.

The best battery value by far is Duracell (actually Deka/East Penn) FLA deep cycle golf cart batteries, 2x6V, around $200 per 200+AH @12V pair from BatteriesPlus or Sam's Club. Deka labeled same batts also sold at Lowes.

 

[dreadlocks]

They can vent hydrogen, which is extremely difficult to contain.. most of it floats off to space, unless you put em in an airtight location normally its no issue as it'll find its way out before it reaches any dangerous concentrations.

even top tier GC batteries like Trojan are equal in cost to no name AGM's, and for most small battery banks of portable/intermittent nature most of us have you never are able to realize much of the AGM gains, other than the lighter wallet.. they are better for full timers and fixed installs.

 

[jacobconroy]

Thanks sirs. These would be installed behind each front seat in a Jeep. I could seal them in cabinets and vent them somehow, but life would be much easier if I didn't have to do that.

How often do you need to fool around with maintenance for GC batteries?

 

[john61ct]

you never are able to realize much of the AGM gains

Only gain with AGM besides being "mostly sealed" and less maintenance,

is faster C-rate discharge, rare use cases where that's actually needed.

Oh, and those whose shallow space forces sideways installation.

They need a much higher C-rate, but don't actually fully charge much faster, maybe save 20-30min over say 7 hours,

and getting them back to 100% is much more critical to their longevity.

The ability to go to deeper DoD is a myth.

Firefly Oasis is an exception, but $500 per 100A @12V, and backordered months.

 

[stix999]

I also have the same vmax. while it is definitely not holding a charge as well as when it was new, the three years of service seems to be consistent with the cycles listed on their website with how it has been used. Now I am debating next steps with needing three new batteries (truck start, truck house, and trailer) have been following dreadlocks intech thread = great stuff (and might be dm’ing you But just not sure the coin is justified for the lithium’s + new hardware vs $6-$7 for three 2nd tier agm s/ FLAs that would get through another few years

 

[Peter_n_Margaret]

The big plus for AGMs is the ability to withstand the constant vibrations of bad roads.
Both my crank and house batteries are Fullriver AGMs that are over 9 years old. My previous wet cell cranks failed after 2 or 3 years. They simply fell apart inside.
Cheers,
Peter
OKA196 motorhome

 

[dreadlocks]

How often do you need to fool around with maintenance for GC batteries?

Depends on loads really, if your just doing small loads like fridge just check water levels a couple times a year like beginning and end of your season (before and after putting it on a tender all winter) and add more distilled water when needed.. if your powering high loads like big inverters or deeply discharging it and quickly recharging at heavy duty cycles then check it a few more times a year as thats probably generating more gasses.

 

[jacobconroy]

Depends on loads really, if your just doing small loads like fridge just check water levels a couple times a year like beginning and end of your season and add more distilled water when needed.. if your powering high loads like big inverters or deeply discharging it and quickly recharging at heavy duty cycles then check it a few more times a year as thats probably generating more gasses.

I might just give GC batteries a whirl then. No big loads for me. Fridge & Propex...maybe an led light or two. My goal is to get setup for 4 to 5 days without having to worry about my battery system. I could idle the rig for an hour each day if needed, but would rather not.

It's really impressive to read about what can be done with LifePo4...but it would be a struggle for me to both learn the necessities and pay for the hardware.

Thanks for all the answers above fellas.

 

[Ducky's Dad]

I had an Odyssey G31 starter battery and a pair of Optima G34 dual purpose marine house batteries in my Power Wagon. Replaced them last summer with three V-Max AGMs, a G31 and a pair of G34s. The V-Max have been fine so far, and the G31 is behaving better at this early stage than the last Odyssey was at this same point in time (8 months in the truck). I went through three Odyssey 31s in that truck and never got more than three years out of one, usually a bit less. My last Odyssey 31 started to lose its ability to take a complete charge within six months of installation, and that was with regular shore power charging and conditioning on an Odyssey charger. I am maintaining the V-Max with a Ctek charger just to feel safe, even though it does not seem to need it. On the other hand, the Northstar 31 in my Tundra is getting close to four years and has been absolutely trouble free.