Forum Discussion
- MEXICOWANDERERExplorerWith regard to automotive style cyclable batteries (Telecomm batteries have entirely distinctive characteristics), here is how I would rate an AGM battery.
Ratio of case size to gross weight (meaning BCI group size to weight)
BCI Cold Crank Test Amperage. The lower the better weight versus amperage.
Advertised 20 hour rate Ampere Hour rating. Again the lowest ampere rating in relationship to weight is an excellent clue.
However let's use the Lifeline 105-amp group 31T versus Lifeline's 31XT. The XT is a 120 ampere hour group 31. 15 amp hours more than the "lighter weight" battery. The 31XT will have a higher CCA rating, but the construction components are just the same - one more plate pair per cell.
So, an equally heavy other brand of battery comes along at near the same weight but with a significantly higher ampere hour rating, and corresponding CCA increase over the Lifeline, plate area has to be increased. More and thinner plates.
For a useful test of an unknown accumulator, the first thing to do is try and find it's BCI group number by measurement of the case.
Find a corresponding "known" thick plate battery i.e. the Lifeline.
An adjustable carbon pile load test is performed. Whatever amperage it takes to slump voltage to 9.6 volts for 15 seconds will be the battery's existing CCA rating. I say existing because an undercharged or mistreated battery would naturally underperform. Recommended, is a full charge then a conditioning charge, wait one day then perform the CCA test.
It would be a waste of time to do this with an old battery. The history of the DUT has to be known in advance. The Lifeline method of capacity testing is most accurate to determine the viability of an old AGM CCA test.
Why am I so fixated on cycle life and overall lifespan? I project a scenario in which I estimate what an unexpected failure is *really* going to cost me. Someone who lives in a major USA metropolitan area will have a far less intensity of hassle than I would. By the same token, I can substitute an emergency flooded 12 volt battery out of doors, then hassle about how to pass wire through concrete and reconfigure the charging protocol. Someone who is relying on a precious boondocking vacation in a remote area is similarly at risk of having a disrupted or destroyed (expensive) vacation by a premature battery failure. If the object is no money, preventative replacement can be a problem for those folks not well endowed with surplus income. Money is no object on the other hand can well afford preventative replacement management. One class of individual -must not- judge the other. It would be irrational. I fall into the obviously vulnerable first of the two categories. To have a individual possessing an abundance of disposable income along with minimum risk of inconvenience ridicule my doctrine would show either a lack of conscious awareness, or a lack of intelligence. That's pretty abrupt even rude but it's fact not opinion. - pnicholsExplorer II
NRALIFR wrote:
... do you have any opinion of the VMAX Tanks brand of AGM batteries? I’ve been using one (I think it’s a XTR31-135) in my TC for about two years. I can’t seem to find any technical specs that include plate thickness, but they do weigh more than the group 31 Lifeline AGM. Nine pounds more in the case of the one I’m using. I bought mine on Amazon for less than the price shown on the VMAX site.
Thanks for mentioning those VMAX AGM batteries. This VMAX model looks like it might be right up there near the top, too: https://www.vmaxtanks.com/MR137-120-Deep-Cycle-High-performance-AGM-Battery_p_28.html
Also notice that those VMAX batteries have a float spec of 13.5-13.8 volts. This is right at the output range of stock RV converters, so no need to buy another converter unless you need to charge faster than 13.5V - 13.8 volts will get you. - pnicholsExplorer IIThat Lifeline GPL-31T AGM 12V battery is not Lifeline's best Group 31 AGM battery for RV use.
The one that I researched a couple of years ago and is a better way to go was their GPL-31XT AGM 12V battery. It's the same physical size, but weighs 10 lbs. more and has more capacity ... at 125 amp hours.
Here's the GPL-31T specs: http://lifelinebatteries.com/products/marine-batteries/gpl-31t/
Here's the GPL-31XT specs: http://lifelinebatteries.com/products/marine-batteries/gpl-31xt/
Here's a great price on the GPL-31XT - considering the additional amp hours that you get from it: http://www.bestconverter.com/GPL-31XT-12-Volt-125-Amp-Hour-Deep-Cycle-AGM_p_593.html#.WcVQkNhryMo - greenrvgreenExplorerMex, I've bought from BatteryStuff and they are legit, FWIW. Personally I'd go with the LIfelines. Don't be scared away by a clearance price, that's how BatteryStuff prices everything--against their historical highest and/or theoretical retail price, and then offers a "discount".
I always just compare current prices and they're usually the best. - NRALIFRExplorerMex, do you have any opinion of the VMAX Tanks brand of AGM batteries? I’ve been using one (I think it’s a XTR31-135) in my TC for about two years. I can’t seem to find any technical specs that include plate thickness, but they do weigh more than the group 31 Lifeline AGM. Nine pounds more in the case of the one I’m using. I bought mine on Amazon for less than the price shown on the VMAX site.
:):) - MrWizardModerator
Top it off I found DW No 1 to be defective and couldn't take her back - the early cancellation of contract proviso was a hum dinger.
WHEE HA !
i my case that was DW #2
i can depend on you Mexi - to give me a good laugh - MEXICOWANDERERExplorer
free radical wrote:
My brand new Lifeline battery failed three months down the road,and wouldnt hold charge,
Couldnt even return it as theres no dealers in other province I moved to,,400$ down the drain..
Live and learn
There is nothing sadder than seeing a brand new Rolls Royce with the hood propped up. Snapped a new Wiha screwdriver, stripped a new hundred dollar Snap On ratchet, blew out a near new Michelin pickup tire, had to walk a mile to a phone because a friend's fresh from the dealer, new pickup quit, got a bad 25 dollar hair cut, had a grease laden twenty dollar plate of prime rib and damned if I didn't stub my toe on an auditorium basketball court. Top it off I found DW No 1 to be defective and couldn't take her back - the early cancellation of contract proviso was a hum dinger. - free_radicalExplorerMy brand new Lifeline battery failed three months down the road,and wouldnt hold charge,
Couldnt even return it as theres no dealers in other province I moved to,,400$ down the drain..
Live and learn - MrWizardModeratorwe know concorde are great .. BUT !
batteries and solar, san deigo area12volt, group 31, AGM, Deka, Blem Batteries and sometimes a variety of other 12volt Deka Batteries. Always at a low price.
6volt Brand New Trojan Batteries in T105 and/or T105plus and L16 E-AC and sometimes L-16 RE Just In, Limited Time-NEW 8D AGM 245 AH Batteries, 8volt New Blem Batteries.
those Deka batteries are $129 each plus core charge or exchange
OR
North Star AGM 100 AH
North Star 100ah AGM - Vixen21Explorer
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