lifeline agm batteries

papab

Has anybody here had a good experience with a lifeline battery and some partial state of charge time?   I ask because I have one thats about 1.5 years old that is done and I can get a good deal on a replacement, but I'm hesitant to buy another one.   Only about 60% capacity and it takes a long time to charge up at the proper absorption voltage.   

This is in a camper van with 210W solar and a 60 amp xantrex charger.   I've taken really good care of it the last 14 mo,  but I may have stressed it last year on a trip when it was fairly cloudy and I typically didn't drive the 6 hours or so that it took to get it 100%   I think I went about 2 -3 weeks without getting to 100%, but it never got below 50% and got to 95% several times.   I thought I got it back with a conditioning cycle and lots of time at float, resting voltage was 12.85.   Then for the last 5 mo I've been in the van 95% of the time and I've been keeping it topped up pretty well, maybe a week with out a full charge, but 98% in that week, never below 70%.    It's taking long and longer to get a full charge so at lifeline tech support's suggestion I tried a couple of conditioning and discharge cycles.  During the 21 amp discharge test down to 11.3V,  I only got 84 ah out of the 150 aH battery.   I could probably live with the lower capacity, but it takes forever to charge up.  On a recent test, using the xantrex charger, from only 18 aH down it took 8 hours to charge up.  

mike95490

If you can take it back on warranty, do it.   You are messing around with a sick battery that will wait for a rainy night to die (yes, it's the same special sensor in a xerox machine that causes it to jam on YOUR job)

littleharbor2

Two questions come to mind. Is your controller an MPPT type? What is the Vmp of this panel? If not MPPT and not a 12 volt nominal panel (17.5-18.5 VMP) you aren't getting anywhere near the potential of the panel.
  This time of year the sun is at it's lowest point in the sky. Is your panel mounted flat on top of your camper? if so it isn't getting much insolation and would struggle to create any substantial amperage thus taking a really long time to bring up your battery.
 AGM batteries have a pretty long shelf life as long as they don't sit too long in a substantially discharged state.

Marc Kurth

I have several questions for you:

What are the measured absorption and float voltages on the Xantrex charger? (actually check them)
What is the output voltage of your alternator regulator?
Are you using temperature compensation?
What is the date code (small round white sticker) or serial number on the battery?
How did you perform the conditioning cycles?
Why did you use 11.3v as a cutoff for the capacity test?
What was the approximate current draw shown on the charger when recharging from 11.3v? (Assuming a Truecharge 2?)
How are you determining that it took 8 hours to fully charge with the Xantrex 60a charger?

The GPL-30H is well known to be a very good battery. I can give you a lot of history of them by the hundreds.

Marc

papab

The absorption voltage on the xantrex is 14.3 or 14.4, temperature compensated.  the van voltage is usually 14.1 or a litle higher.   I can use the charger when driving so I'm not limited to 14.1V.  The charger switches to float too soon, at 6 amps.  Last winter I figured out that I could switch the charger to gel when it was in float, then get 14.4V in float.  Still too low if it's cold. Going from memory, the date code is BO.  The conditioning was 16V for 8 hrs.  I was using inverter as the load for the discharge so I quit when it beeped due to low voltage.   The xantrex was putting out 60 amps in bulk.   I determined the 8 hrs from the finish amps and the SOC.
I have a trimetric bat monitor and solar charge controller (pwm)
I have 160W on the roof, 50W portable.  Not much this time of year, about 7 amps, but I'm usually only down 15%

Marc Kurth

Charging voltages sound good, and the fact that the battery was drawing the full available charging power when discharged is a good sign. The charge time makes no sense to me, unless sulfation is still fairly heavy. How did you keep the Xantrex in Equalize mode for 8 hours?

Exloring with the numbers for "sanity check":
- Inverters are continuous wattage devices, so as the battery voltage drops, the current climbs. How did you hold the steady 21 amps?

- If you got 84 ah on the test, then you ran right at 4 hours. Is that right?

- A continuous 21 amp load represents about a 6.2 hour rate on that battery, with a storage capacity of roughly 130 ah at 77-80 degrees F. At 40F, you have a 110 ah battery when discharged at a 21 amp rate. And it goes lower there, when colder.

- Running the capacity test to 11.3v in lieu of 10.5v, represents roughly an 87% to 90% depth of discharge. Which means that the actual storage capacity is higher than 84 ah.

If the battery was warm, then 10%-13% remaining capacity would equate to something like another 13 ah to 15 ah.  If so, then 84+13 = 97 ah against a 130 ah battery capacity at that rate = 75% capacity.

If the battery was 40 degrees for example, it would have a capacity of about 110 ah at the 6 hour rate. So 84+12 = 96 ah against a battery capacity of 110 ah = 87% of rated capacity.

I do not know what the battery temperature was during your test, but your capacity deficit may not be as radical as you thought. Check my numbers to see if I missed something major!  (There was a lot of IPA consumption last night :-))

Marc

Dave Angelini

IPA last night but what will it be tonight?  Hey Marc! Sounds like nothing is wrong here other than aging and winter solstice.
 The PWM solar is not accurate at keeping the voltage below the damage points on an AGM. I am amazed they still sell that beast.
 I would really make sure that it is not over voltaging the AGM. I would use their mppt or another make if I had AGMS.

papab

I kept the xantrex in equalized mode by babysitting it, every hour I reset it to equalize.
Yep, 4.05 hrs for the discharge test. The fridge was coming on and off so it was a constant 21 amps.
The charger is plugged into the inverter, the van 12V system can supply the inverter.
When I did the discharge test it was at 59F. I could probably live with the lower capacity since I rarely go down more than 35 ah, but since it's taking so long to charge I know it will only get worse since I won't be able to charge it back up everyday.

Dave, Why do you say the PWM is not accurate? How much more would I really get from an mppt CC? 10%?

Marc Kurth

Dave, My old buddies Jack D and Jim B stop by with their cousin Johhny Walker now and then, but we had waaaay too much fun years ago . So now I cultivate relationships with tamer friends. It's just that there are so many different IPA's to try and so few nights.....

Dave Angelini

Mr. Prosecco tonight!  Happy Happy!  The costco IPA  by Kirkland is from one of the old breweries I closed a few times in San Jose Ca.

Dave Angelini

If I knew the model number????  The old C40 series had these set-point pots that were finicky and I saw .5 volts a few times from just vibration.
IF you "work" the pot and make sure it is repeatable you probably are OK. An mppt will probably not help you other than what I said about the voltage. 

littleharbor2

My friend Don Julio, from the mainland, just stopped by to wish us ALL a Felis Ano Nuevo.  See y'all in 2017.

Marc Kurth

@papab: Sorry to derail your thread!

I may be missing an important point here, so I want to verify:. Is your Xantrex charger a 120v 60a Truecharge 2? (I think so because of the every hour baby sitting required like mine!)

I am not comfortable that your battery is taking so darned long to reach full charge. At 14.2v to 14.6v, how long would you say that it takes to get down to an amp or two?

Please note that I am not challenging your knowledge - you have very obviously done your homework x 2!  I do a lot of trouble shooting on Lifelines and I am just trying to get a handle on what is happening. (Ask anyone at Lifeline about me when you call them next time)

That model just doesn't do that, unless it's really abused - is what I keep saying to myself. But what you have described doesn't sound abused at all. BTW, out of the last 4,000 of their batteries that I have dealt with, exactly two had a bonafide defect.Neither was the 30H.

I don't suppose that you are planning to be anywhere near Austin, TX?

papab

Marc, I don't think you're derailing the thread, I'd like to understand this too.  
Yes its a 60 amp truecharge2.   They recommend that it is charged when the current drops to 0.5% of C, or .75 amps in my case.  For the test I did a couple of weeks ago, after 3 conditioning cycles it took 7.25 hrs to get to 0.8 amps.  Unfortunately, I'm not going to be anywhere near Austin.  

Estragon

.5%C seems low to me. I have flooded L16s which IIRC are set for 1%C or 4 hours. I certainly wouldn't be running the generator for three hours to get that last 1% or so.

Marc Kurth

The first things that jump out at me:

I didn't realize that you were fighting the final few tenths of an amp of charging current. The 0.5%C (0.75 a in your case) end amps is the spec for a brand new battery in perfect condition. It will climb a bit as a battery ages. Your battery is likely coming up on two years old, so I would use a higher number in my charge planning.

Remember that we are talking about fairly small values here. If your amperage measurement is off by a a tenth or two in the 0-1 amp range, or there was some small parasitic load - the whole picture changes.

I am left wondering something: If the refrigerator kept turning on/off while the battery voltage was continually, gradually falling, how did you keep the current draw constant at 21 amps on the battery for the test?

Based on your measurements and my assumptions, it would appear that your battery has 80% to 85% of original rated capacity. But if you were nearby, I would run a controlled discharge test to 10.5v for you, just to verify.

Marc

papab

That would be great if I could call it good at 1%C.   I was using .5%C because that's what lifeline says in their manual.  Nothing about changing that with age.  Lifeline also recommends returning 107% of the ah taken out.  At  7.25 hrs, .8 amps, it was at 100% and 109%.  If we go for 1%C, thats at 3.7 hrs, 97% SOC and 90% returned.   If I quit then it seems like it would walk down in capacity and get worse quickly.  I get the SOC and returned pct from the trimetric battery monitor.
For the discharge, there was some variation with the fridge cycling, but the aH was measured with the TM.
I agree with your estimate of 80-85% capacity after correcting for the 4 hr discharge rate, 11.3V and temperature.

Marc Kurth

On return amps, I'll need to check the Tech Manual, but memory tells me that it is stated as 102% to 110% depending upon charge rate and temperature.  I am always concerned with walkdown, but I do not think that you will have a problem by using 1% or even a little more. Verify that with Lifeline.

I am always cautious regarding the calibration/accuracy of devices and methods being used to verify capacity. I am NOT saying that you are doing something wrong - only that I have been doing this for a long time and I am big on "verify" before deciding what is right or wrong!

Marc

softdown

Perhaps I missed something, I am not a smart man. Just wondering if the winter solstice could be the big culprit in charging times. What angle are your panels at? What is your latitude? Perhaps I missed something....

papab

Marc, yes it does say 102-110%,  nothing about when 102 is acceptable or not so perhaps anything in that range is OK.   
I'm using a decent qualtiy DVM and a while back I compared a volt reading with someone else's and they were spot on.   Next time I find someone else with one I'll check again.  
Softdown,  the data I posted in #14 was using a xantrex trucharge, not solar.  

papab

So, if 1%C is acceptable and 102% is acceptable, then I'm worrying about it too much.  BUT I'm down to <85% capacity in about 1.5 yrs.

papab

Augmenting my original question a bit.  
Is the charge time equation that lifeline gives, time =  (aH discharged)/(charger output) + 2 hours,  close to accurate?
Can a lifeline battery last 5 years (the warranty) if it doesn't get fully charged everyday?

PNjunction

You may want to doublecheck these values with Justin Godber at Lifeline, but generally it falls something like this for their agm's:

6-9 years if fully charged each cycle
4-6 years if recharged each week and EQ'ed every month
2-4 years if recharged to 85% and EQ'ed once a month
1 year if charged to only 85% and never EQ'ed.

papab

I was hoping for some real world experience, not lifelines claims.  

Dave Angelini

About 5 years in daily cycling offgrid with the 1,100 AH 2V cells. After that a noticeable loss of capacity that can be hard to live with if you are using 5 to 7 KWH per day in winter. There needs to be the capacity in charging to charge daily most all of the year. I do use these very occasionally for people who can't deal with the basic maintenance of flooded or have a really small battery room and the concern arises with ventilation. Not my first choice but a very good company that I can use. I think Marc helped you quite a bit here BTW.

papab

I agree Marc was very helpful.   I still don't have a good feel for whether another lifeline or another AGM or ?? is the best for my application.    Slow charge time, sensitivity to partial state of charge and sensitivity to charging voltage might be the issues 

Marc Kurth

papab said:

...............................................
Slow charge time, sensitivity to partial state of charge and sensitivity to charging voltage might be the issues 

@papab: I can provide lots of anecdotal reports about Lifeline battery banks that I have personally been involved with, but you have effectively listed the potential pitfalls with using any AGM battery. There is not an FLA, Gel or AGM on the market that is immune to all of the parameters you listed.

Every battery design has its own strengths and weakness that must be weighed against long term owning cost. Are AGM's perfect, or the best battery for every app?  Oh, Hell no.

Have you explored going FLA?
It would seem like lithium would be a good answer for you?

If you know that your operational needs do not include what a Concorde battery "needs".......but if you need an AGM, seriously consider buying a much cheaper battery that will be replaced more often!

Marc

PNjunction

Papab: Some real world lifeline experience can be seen from the Morgan's Cloud marine project online.  Might be useful.

Marc: I agree with you completely - while I *prefer* AGM, one always has to take into account ALL the other variables.  There are many ways to go, including manufacturer and chemistry.  There is no one-shoe-fits-all battery made to my knowledge, so your outlook is refreshing.

Estragon

Seems to me the main advantages of AGM in this application are; little or no gassing, slow self- discharge, and ability to install in orientations other than upright. If none of these features are important I personally don't think the extra cost of AGM is justified over flooded. Flooded also have the advantage of being able to check SGs so you don't have so much guesswork in charging.

I have flooded in the companionway of my sailboat, and while they've worked okay I will be seriously considering AGM replacements when the time comes.

PNjunction

Be sure the floodies aren't mounted in a bow-to-stern orientation to avoid exposing the plates while in motion....

Estragon

Afraid they are - only way they fit in the box. Not sure it makes a lot of difference though. Motion fore/aft in waves probably about equal to heeling when sailing close to the wind. They were last changed in 2009 so they don't owe me anything.