AGM batteries already bad?

[turk123]

Originally Posted by uncle_bob

Hi

If you want to really be careful, disconnect the batteries from the trailer before you do the reconditioning run. The voltages you will see doing it are a bit above the max input voltages on some "12V" electronics .....

Bob

I thought of that and kept a good eye on it. It did not go over 13.82v over the entire time, about 15 hours. I guess I am questioning if that is a true desulfation, but after going to the trailer today I measured 12.92 and after running a few things for a short time (fan, lights, range fan) the voltage was at 12.84 and steady. That was with sensors running czone running and hotspot.

That's clearly better than I have ever had with the one-year-old batteries. May not be a fair test with that small load on and not letting the batteries sit for 3-4 hours, but it is encouraging.

[GMFL]

My “equalization/de-sulferization” will run up to around 15.3 volts.

[turk123]

Originally Posted by GMFL

My “equalization/de-sulferization” will run up to around 15.3 volts.

I really need to check that with the manufacturer. It may have something to do with running on two batteries at once. I may have just run a standard charge and not run at all. Guess it's time to install that disconnect switch I've been carrying around and disconnect the batteries from each other.

It also means I have to empty the refrigerator!

[Silvr_Bullet]

Originally Posted by uncle_bob

Hi



Use it and see how it does.



Bob

Thanks Bob,

Seriously is that the only way.

K

[turk123]

Originally Posted by Silvr_Bullet

Thanks Bob,

Seriously is that the only way.

K

I actually found the user manual to my charger online and it's about 3 times larger than what I received in the box. It talks about batteries that get damaged by discharging too far. It said they actually tend to read higher voltage when charged, but lose their power very quickly when in use.

I also found out that my charger has to only desulfate on battery at a time. Only then will it raise the voltage to a higher level. It makes sense with the onboard electronics. I guess I make the trip back to the trailer to try again.

[uncle_bob]

Originally Posted by Silvr_Bullet

Thanks Bob,

Seriously is that the only way.

K

Hi

No, you can indeed run some tests on the batteries.

First charge each battery for 48 hours on a "good" charger. Let it sit for at least 24 hours after you take it off the charger.

You then put a load on each battery individually that will pull roughly 8 amps. Monitor the voltage every hour and look at the curve. To get the full curve you would go way past the point most of us stop running a battery.

After that charge it back up again and do the same thing with a much heavier load (16 to 24 A depending on the battery) and look at that curve. Monitor this one every 15 minutes.

Next, charge it back up again and let it sit for a month (or three) while watching the voltage. After that do an 8A discharge test again.

Once you are done testing, charge both batteries for at least 48 hours before putting them back in the RV.

At that point you will know how the battery does under both high and moderate loads. You also will know how it's doing for self discharge. You will have a number like 3% per month and 82.3% capacity. Now that you have those numbers, what do you do?

There are a lot of people out there running batteries that (likely) only have 50% of their rated capacity. They are perfectly happy doing that. There are also people out there who have batteries that will go flat in three months without a trickle charger. They also seem to be quite happy. Equally there are others who would have dumped those same batteries and head over to Costco. People make decisions based on their usage rather than "battery numbers".

The one thing that pretty much everybody gets excited about is a shorted cell. If that happens, you will not be able to charge the batteries. That's a very obvious problem and off to Costco you go. Only a small percentage of batteries fail this way.

You can head over to the battery guy and have him do this or that. It's a good bet that he's not going to do a 1 month self discharge test. His testing may or may not be in any way relevant to how you use a battery in an RV. What he does likely *will* determine if you get a warranty replacement.

Battery spec sheets generally call out 80% of capacity as "end of life". Self discharge numbers are all over the place. Some very good batteries are rated for crazy self discharge numbers (like 15%). One wonders why in the world they rate them that way when nobody ever sees that .....

Bob

[uncle_bob]

Originally Posted by turk123

I actually found the user manual to my charger online and it's about 3 times larger than what I received in the box. It talks about batteries that get damaged by discharging too far. It said they actually tend to read higher voltage when charged, but lose their power very quickly when in use.

I also found out that my charger has to only desulfate on battery at a time. Only then will it raise the voltage to a higher level. It makes sense with the onboard electronics. I guess I make the trip back to the trailer to try again.

Hi

You have to get over 14V to do any sort of desulfate process on the battery.

Some well known chargers go as high as 18V. Indeed I would not use a charger like that on my batteries. They claim that chargers only get used on "end of life" batteries and any damage done really doesn't matter ..... yikes ....

Not relevant in Texas quite yet, but all the magic voltages (including the rejuvenation stuff) are temperature dependent. At sub freezing temperatures the voltages *will* get a bit alarming.

Bob

[turk123]

So here is the treatise on battery desulfation and the new technology to do this.

https://www.chargingchargers.com/tut...sulfation.html

I went back to the trailer and unhooked everything! Two clean terminals on each battery. I hooked the charger to one of the batteries. It started out at 12.85v and slowly kept climbing (30 minutes) to 15.5v where it stayed for about 10 minutes. It then very quickly dropped to 13.55v and pulsed from 13.41 to 13.55 about every two seconds. My multimeter could not keep up but displayed those highs and lows with other voltages in between. I stayed for about two hours more and it pulsed the whole time. Manual says it will run for 4 hours. This is the technology developed by PulseTech.

It finished while I was gone, but after returning, the charger had a solid light on "repair" meaning it was done. I moved the charger to the other battery and it is running now. I measured the voltage on the battery no charger and it said 13.1v. I will measure it tomorrow morning to see where it settles out to.

From what I've read, pulse technology has replaced the higher voltage type chargers.

But then there is Battery University! John Fetter does not believe there is any way to remove crystals from plates especially with pulse technology. Read the article but be sure to read the comments below. He is not a fan. Very interesting reading though. Lots of claims.

https://batteryuniversity.com/learn/..._to_prevent_it

So maybe just getting a few good charges in the tank using a new 8 stage charger is still worth the effort. And keeping a maintenance charge still is recommended.

[turk123]

I did have time to get my blue ocean disconnect switch out and figure the routing and how to install it. Thanks, Air Forum for the great threads on this.

http://www.airforums.com/forums/f449...ch-177014.html

I can now isolate the battery bank in case something happens to the trailer or if I want to "pulse" the batteries to death!

[ddrg]

Originally Posted by turk123

I just talked to DFW Airstream and they can get me in late December. Thanks, Airstream. Service tech Heckter said this is the first year we are really swamped with repairs. Hmmmm, no kidding Heckter, wonder why?

I have to take the batteries out and they will swap them if they test bad. I may have to have them tested elsewhere if they can't do it.

Lifeline dealer?

Our Lifeline AGM's started going bad in July this year, which came with our 2018 Globetrotter purchased in January 2018. Our dealer and Jackson Center both said that batteries aren't covered by warranty. They also didn't know about any manufacturer warranty.

So I called Lifeline last Monday and discovered that the batteries were actually 34 months old, and that the batteries have a 60 month prorated warranty. The support person honored our January 2018 purchase date - last Wednesday two brand new AGM's arrived for $225. I'm obviously very happy!

Hope this helps someone... Duncan

[turk123]

That's great Duncan. It's good to know they support their product. Lifeline seemed genuinely interested in my problem and was very helpfull.

[uncle_bob]

Originally Posted by ddrg

Our Lifeline AGM's started going bad in July this year, which came with our 2018 Globetrotter purchased in January 2018. Our dealer and Jackson Center both said that batteries aren't covered by warranty. They also didn't know about any manufacturer warranty.

So I called Lifeline last Monday and discovered that the batteries were actually 34 months old, and that the batteries have a 60 month prorated warranty. The support person honored our January 2018 purchase date - last Wednesday two brand new AGM's arrived for $225. I'm obviously very happy!

Hope this helps someone... Duncan

Hi

Indeed there are a number of outfits that will honor the "sale to you" date as the start of the warranty. Yet another good reason to keep your paperwork handy *and* to mention that date when you chat about warranty issues. Pretty much everything that goes into your RV sat in inventory for a while before the vehicle shipped out .....

Bob

[uncle_bob]

Originally Posted by turk123

I did have time to get my blue ocean disconnect switch out and figure the routing and how to install it. ......:

Hi

I suspect it's really a Blue Sea disconnect switch

https://www.amazon.com/Blue-Sea-Syst...s%2C150&sr=8-5

A pushbutton alternative:

https://www.amazon.com/Blue-Sea-Syst...87204155&psc=1

====

Hope you survived the tornado !!!!

Bob

[turk123]

[QUOTE=uncle_bob;2300302]Hi

I suspect it's really a Blue Sea disconnect switch


====

Hope you survived the tornado !!!!

-------------------------------------
I got to the trailer today and it did survive although it is covered in dust!

The battery that went through the repair yesterday was at 13.10v. The lastest one was at 13.18. That's a good amount and better than I have ever had.

I then spent a couple of hours wiring is all back together using the disconnect switch. If I drop that socket down between the battery and the back of the battery box one more time . . . . . .! Good thing no one was there at the storage as I sounded like a drunken sailor!

Got everything wired through the switch except the jack and the Zamp solar connector. I figured I might want to use the jack without turning on the entire trailer. Putting it back together was not that bad as the hots are isolated and the black was not connected till the end. That way there is no ground to short the red on. Good practice.

Fired it up and there was no fire.

Czone is showing 12.78v with the minor load. That means it is actually 12.98v. It started to drop a little after awile.

Here are some pictures! We are located 1 1/2 miles past the eastern most path of the tornado. Right on target!

[SSquared]

Originally Posted by Silvr_Bullet

How does one determine the health/damage to a battery after it discharged past recommended.
Thanks

Lifeline has a "Technical Manual" for their batteries, and it specifies the following process:
1) stabilize the battery temperature at 77 degrees F (25C)
2) Fully charge
3) Discharge at a steady 25 amps until voltage falls to 10.5
4) Compare the number of minutes that lasted to the published spec for the battery.

The 25 amp current number apparently applies to all their batteries, regardless of size (which I find surprising, but what do I know).

I recently attempted this on my Lifeline batteries, I did not have an exact 25 amp load, nor a temperature-controlled test lab, so I had to apply some windage to my results. (Lifeline published charts with temperature and voltage/current drop)

My batteries are around 68% after 6 seasons of use.

Lifeline says to use a "conditioning" (equalizing) charge for a battery under 80%.

[Renascence]

Asking only for learning more about the two battery types.
Would lithium batteries have had similar issues?

AGM batteries and lithium batteries are options for solar setups and I am just wondering if for me in the future their is an option to avoid Turk123's issues.

Thank you.

[turk123]

Lithium batteries do not have sulfation issues. Only lead-based batteries.

[uncle_bob]

Originally Posted by Renascence

Asking only for learning more about the two battery types.
Would lithium batteries have had similar issues?

AGM batteries and lithium batteries are options for solar setups and I am just wondering if for me in the future their is an option to avoid Turk123's issues.

Thank you.

Hi

As mentioned above, AGM (absorbed glass mat) is simply another way to make a lead acid battery. You reduce the need for adding water to the cell (in many cases eliminating that need). The same process reduces the battery's tendency to outgas and explode. You also reduce issues related to electrolyte stratification with AGM.

There always is a gotcha. AGM is not a cheap way to make a battery. You very much will pay a premium for one. A flooded cell will be significantly cheaper than an AGM of the same capacity.

====

Lithium batteries are (again as noted above) an entirely different chemistry. They most certainly do hav issues. The issues they have are different than what you see with lead acid.

Bob

[ddrg]

Originally Posted by SSquared

Lifeline has a "Technical Manual" for their batteries, and it specifies the following process:
1) stabilize the battery temperature at 77 degrees F (25C)
2) Fully charge
3) Discharge at a steady 25 amps until voltage falls to 10.5
4) Compare the number of minutes that lasted to the published spec for the battery.

The 25 amp current number apparently applies to all their batteries, regardless of size (which I find surprising, but what do I know).

I recently attempted this on my Lifeline batteries, I did not have an exact 25 amp load, nor a temperature-controlled test lab, so I had to apply some windage to my results. (Lifeline published charts with temperature and voltage/current drop)

My batteries are around 68% after 6 seasons of use.

Lifeline says to use a "conditioning" (equalizing) charge for a battery under 80%.

After reading the Lifeline Technical Manual tonight, I have two questions:

1. Is the 2018 Globetrotter charger sufficient to charge the dual Lifeline GPL-24T batteries according to Lifeline's recommendations?
2. What would be a good standalone charger to charge a GPL-24T battery?

Thanks... Duncan

[SSquared]

I'm not an expert......I just have read the Technical Manual. The manual says that the batteries can be charged at an extremely high rate (five times the battery rated amp-hours!). Also, for batteries undergoing "repetitive" deep cycling (below 50% charge), they recommend using a charger that can provide at least 20 amps per 100 amp-hours of battery capacity. This is within the realm of what some RV chargers can do.

I don't know what model charger is in your Globetrotter. I'm not familiar with today's standalone chargers, either. Sorry.