Lifeline AGM and extreme temperatures?

[JiminDenver]

Im working a deal on three Lifeline 8-D AGM's but am wondering if the -20f or 100+ F temperatures they will be exposed to mounted in the trailer will have any detrimental effects. They would either be on the solar system or charged and disconnected altogether.

Thanks in advance.

Mex

These are unused like the Leoch were but older and kept on a charger. These are $225 each vs the $370 for the Leoch 8-D's

[JiminDenver]

Well two of them are above 13v, the other at 12.88v and I'm sitting here wondering what the heck did I just do. I'm reading Lifelines manual and see I need a better charger than the good ol 2/12/70. I'm pretty sure the TS-MPPT-60 can handle a conditioning charge but not a deep discharge recovery. That is of course when it is set up and the sun shines, neither has been often lately.

Tomorrow is sunny so I will set up the system and hit the lower voltage one first. I want to see how each does alone before hooking them together. One is lower in voltage, I don't have any lugs yet and I'm not sure my system has the power needed to slap all three of them around at once.

As for the weight, any batteries were going to add weight. These are going over the axles opposite of the kitchen. That will let me put the controller in the rear compartment and have shorter runs of wire everywhere. The rear hold is accessible thru the bunk so the controller will be mounted on a board that can be lifted up to working level. Not having the batteries on the tongue will allow me to upgrade to a 50 gallon fresh water tank.

Got the solar, controller, inverter, wire and batteries. Time to work out the switching, fusing and layout. I might even get to see it all work this season.

[MEXICOWANDERER]

Efficiency of recombinant properties is temperature dependent. Recovery is compromised when internal temperature raises to the point that venting valves open to relieve pressure. This opens the door for loss of electrolycized water vapor loss. Water vapor loss CANNOT HAPPEN with relief valves intact. This is the principle behind recombinant technology. OEM considers this level of technical information to beyond the scope of the average consumer. Temperature DIFFERENTIAL as well as ultimate battery temperature are the keys to successful AGM management under highly stressed conditions. Lifeline mentions a C10 charge rate is appropriate. Under extreme elevated battery, ambient or Delta T (differential) temperature, full capacity charge acceptance must be avoided. This is true of any Valve Regulated Battery. Compromising VRB sealing integrity is not intelligent. Period. No exceptions. No hair-splitting.

[MEXICOWANDERER]

Your hair-splitting scalpel needs a tune-up.
Porosity of active plate material accounts for a significant static level of charge.
The THINNESS of plates, the porosity of plates, plus construction for chemistry determines the characteristics of a flooded battery.

I went toe-to-toe with the phone answering "Applications Engineer" at Lifeline. He too suggested a high voltage, maybe "13.8 volts" would cause loss of water if present year after year. Why the exaggeration? I did not say 13.8, I spelled it out, THIRTEEN POINT SIX VOLTS.

It boiled down to this...read carefully...

"Our engineers feel a float voltage of thirteen point four volts will offer the maximum possible lifespan on a battery at float"

This isn't wrong. But the age advantage is almost asinine. Maybe a year IF THE BATTERY IS UNDERGOING UPS DUTY and total lifespan is in excess of twelve to fifteen years.

Don't spin the steering wheel when the front tires are stationary and enjoy added tire life (200 miles on a 40,000 mile tire).

And please don't throw Rolls and Surrette recommended flooded float voltages at me as a challenge. Rolls is right on the dot with their voltages.

I have a 50Kg gram scale here. Measures resolution to .1 gram. A 5-1/2 digit bench meter, and thermocouple that defines Fahrenheit to .1 degree. Ya think just maybe I have the ability to measure resolution of .001 ampere? Ya think a weight loss of a 35 kg battery of .1 GRAM (not ounce - GRAM) would not be detected? How much H2O in one tenth of a gram?

I doubt I REALLY doubt even Concorde goes to such elaborate steps to determine limits of suitability of a particular float voltage correlated to temperature. I do it for FUN. I have caught so many application engineers telling ridiculous fairy tales that I refuse to talk with them unless really forced to. The hidden design engineers espouse facts and by god they HATE to be challenged. They adopt ROTE replies to a majority of issues and stick by ROTE. When pressed to defend ROTE they get veins sticking out of their neck and temples. I have done this for many decades and as Larry D'Aquino at Ramcar told me. "Of course you are correct. But don't make a habit of embarrassing engineers - some of them might have a .45 in a desk drawer".

The validity of abandoning a Lifeline for a .2 float voltage disparity is sad. I tried every example I know, explaining the ridiculous contradiction of imposing a fixed .2 volt differential across a temperature range of ONE HUNDRED DEGREES FAHRENHEIT. That didn't work. Neither did explaining the contradiction of using a Lifeline at underhood temperatures at automotive charging system voltage values.

You are entitled to do as you wish. I have presented my side of the issue with a plethora of easy-to-understand examples. I must now abandon this issue as there is nothing to be gained by head butting. Hopefully enough folks have read this to arrive at a common sense deduction and conclusion.

Saludos! pnichols 🙂

[pnichols]

MEX wrote:
But just because the battery may hold high static voltage is not a guarantee of good quality.

Hmm ... I thought a poster recently mentioned a Lifeline AGM sitting at about 13.1 volts terminal voltage after resting awhile after a full charge? (My memory could be wrong on this, however.)

My Group 31 95 amp hour yellow top cylindrical Optima AGM sits at about 13.1 volts for weeks after a full charge. My Interstate AGMs sat at about 12.8 volts for weeks after a full charge. My new Fullriver AGMs look like they're going to sit at about 12.8 volts after a full charge.

What can be the cause of this ~0.3 volt static voltage difference?

[pnichols]

MEX wrote:
Do you see skull and crossbone symbols NOT FOR AUTOMOTIVE USE?

Nope ... but I don't see starting batteries under hoods lasting 9-10 years either ... like many deep cycle batteries floated properly in RVs do. 😉

So, what's your take on a Lifeline guy on the phone telling me that their batteries would dry out prematurely if I floated them at 13.6 volts year after year like I did my Interstate (C&D Technologies) AGM RV batteries for ~ 8 1/2 years?

[MEXICOWANDERER]

I have seen flooded batteries do it too. It may dawn on you this is a QUALITY issue not a chemistry distinction. Self discharge SHOULD therefore be highest in AGM batteries with the lowest impedance - right? Sorry. Wrong. A battery has fully capable tendencies to eat itself if constructed wrong. An AGM that has a high static discharge is inferior. But just because the battery may hold high static voltage is not a guarantee of good quality. Some fall head-over heels for hyperbole and overly fussy technical recommendations. It's a free decision to manage personal property according to choice. Just remember those thousands of AGM batteries basking in underhood temperatures at voltage values far in excess of float recommendations. Do you see skull and crossbone symbols NOT FOR AUTOMOTIVE USE?

[pnichols]

Mex wrote:
But skipping the purchase of an AGM brand because of a two-tenths of a volt disagreement between set maintenance charging voltage value and OEM battery recommendation, is just plain silly.

Now .... if one could just get the OEMs to agree that their published maintenace voltage values are silly if ever a warranty replacement becomes an issue between an OEM and a user.

BTW, if it's OK for all AGM batteries to use the same float voltage irrespective of electro-chemistry and construction .... I wonder why some AGM batteries off the charger sit week after week holding 13.1 volts on their terminals after being fully charged, while other AGM batteries off the charger sit week after week holding 12.8 volts on their terminals after being fully charged?

I have personnally seen this AGM terminal voltage difference during long-term non-use in my various AGM batteries in equipment, pickup trucks, boats, and RVs. The times have been too long, in my experience, for the differences to be due to surface charge bleed-off times.

It's hard to believe that all lead acid AGM batteries should act, and be treated, the same ... terminal-voltage-wise ... regardless of what combinations of materials and chemistry were used in their manufacture.

So far I'm willing to believe that this goes for float voltage differences, too. IMHO ... Lifeline, Fullriver, C&D Technologies, Rolls Surrette, etc. may agree with this, too.

[MEXICOWANDERER]

Temp compensation is the hot setup. But conscientious manual setting is even better. After I bring my empty coffee back in, after screaming at garden vegetation to grow faster, I fine tune float settings. Time consuming - must take 4-seconds.

[JiminDenver]

True. Luckily it has a 3000 lb CCC.

Don, I bought the TS-MPPT-60 because of that and other features.

[Chris_Bryant]

Three 8D's are going to make your rig an AmeriHeavy.

[pianotuna]

They are more temperature resistant than flooded--but for longest life make sure any charger uses temperature compensation.

[MEXICOWANDERER]

If Lifelines last years and years at underhood temperatures in ambulances at vehicle charging system voltages, then what say you to veritable battery paradise temperature and voltage wise?

The AGM temperature/voltage "kick" has gotten entirely out-of-hand on this forum. LIFELINES ARE LESS TEMPERATURE SENSITIVE THAN 5% ANTIMONY BATTERIES! I did not say VOLTAGE SENSITIVE. Imagine what happens to an AGM in Phoenix in July, underhood on a 120 degree summer afternoon. Yeah it's not going to live as long as a laboratory maintained AGM on float. But such a comparison twisted so make it sound as if the AGM is doomed, is worse than foolish.

Understand it clearly. Corcorde wants to brag it's expensive batteries have phenomenal lifespans. I tried to make float voltage maintenance have meaning on this forum by raising SG to maximum then reducing float voltage to absolute minimum to reduce maintenance current to next to nothing without having specific gravity start to slup. Lifeline, being perfectionists try to impress this philosophy upon customers without explaining PRECISELY how their philosophy fits into the overall scheme of reality. Their meticulous attention to detail just tickles me but the buying public adopts meticulous recommendations as gospel. Do not forget the same people who issue Mil-Spec bulletins and qualifications also construct user manuals for the public. Concorde demands their customers toe the line right to the millimeter. Other AGM companies have adopted a looser than a goose user manual. A German pre-war hunter's manual is a good parallel. It demands the shooter take an almost fencing grade degree of posture placing the feet, hands and fingers, just so. Remember, the game could care less, but etiquette demands it without compromise.

BuShips battery maintenance manuals for US submarines is similar. You would not believe the intense, rigorous level of goose-step grade maintenance and daily testing and proofing. Boats had to return to Mare Island to exchange batteries and the military demanded the crew baby those batteries as if their life depended on it.

This is definitely not an endorsement of going to extremes and getting sloppy with charging control - it is a reality check in which manufacturers of a premium priced product worry about images and perceptions. AGM manufacturing is not a lucrative profit endeavor, sorry, edeavour. Cost of materials, construction, and testing is pricey and profit percentage is around 150% that of a standard premium flooded battery. Remember base prices start at a higher figure. The quantitative production numbers are tiny compared to flooded batteries.

But skipping the purchase of an AGM brand because of a two-tenths of a volt disagreement between set maintenance charging voltage value and OEM battery recommendation, is just plain silly.

[JiminDenver]

According to the lifeline manual they can be stored fully charged anywhere from -67f (-55c) to 122f (50c) They can be used in temperatures from -40 f&c to 160f (71c)

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