Battery drainage

[Stan the Van]

We are still trying to figure out our "new" AI GT and the charging/drainage on the batteries. Overnight the batteries will drop significantly to where they cannot even turn on lights. We have been using our home 110V to charge to keep things going but if we unplug for the night as we would camping without hookups we lose the battery power. The only thing we have on as far as we can tell is the fridge and freezer. But even these turn off but morning if we are not plugged in.
CHS VOLTAGE before: 12.0V, CHS VOLTAGE after unplugged 6 hours: 11.0V
HSE VOLTAGE before: 12.4V, HSE VOLTAGE after unplugged for 6 hours: 9.8V

Is this normal? Or as I am wondering, if previous owner did not take care of or charge batteries during the months of non-use which depleted their storage capacity.

[3OnOurWay]

The batteries don’t appear to have any usable life. Certainly not viable if they can’t go the night to power fridge.

What year AI? LiFePo lithium or ? Also I would suggest check the settings in solar, magnum shore charger ( if it’s set at 50% charge rate, and you’re in 120 v 15 amp, that could be 7.5 amps, into 200amp batteries would need close to 30 hrs of charging not including the draw of fridge etc

Our 2021 24gl Lithium system 200ah factory can go about three days no solar Depending on power usage lighting tv inverter etc .

Attached is one example of a diagram.

[3OnOurWay]

I am a huge fan of smart shunt it gives a more accurate idea of batter charge / drain and health of electronics phantom draws ( your propane switch one uses about 1.0 amp.
Here we changed all factory supplied working components for upgraded w Bluetooth for security peace of mind

[Stan the Van]

Thanks, it's a 2021 with lithium batteries. Does appear that the batteries are shot!

[3OnOurWay]

Sounds like w have similair model. Yes the batteries don’t sound to be operating up to their full performance. A lithium battery only getting to 12.4 doesn’t sounds right. From factory our setting were wrong and had been that way for 3 years before our purchase.
I highly suggest checking settings. It also help familiarize yourself with a lot of different systems that our on board

[uncle_bob]

Hi

One note to the OP: Your user data (entered via the User CP tab up top) shows that you own a 2024GT. Your post indicates a 2021. If indeed you have a 2021, I'd suggest updating your info so it's correct.

With a charger that functions properly, but is set to lead acid, your batteries will get up to about 13.6V at the end of a charge cycle. If the converter is set properly to Lithium, they will get up to about 14.5V or so.

Voltage is a really poor way to monitor batteries. In order to get close, you need to put a multimeter right on the battery posts. Given where they put batteries on a van ... not so easy.

Almost regardless of battery condition, the charger should get them up to those voltages if you let it run for a while (12 hours maybe). Problem batteries will quickly discharge from that point, but they still usually get to the top voltage.

I think it's a good bet that your charger has issues. The gotcha here is that they may well have used a different one in 2021 than in 2024. First question would be: Which one do you have?

Both your house and chassis battery voltages appear to be problematic. That also would suggest a charging problem.

If you *do* have a 2021, it would be unusual for it to have come with lithium batteries. Has it been converted from lead acid to lithium by the previous owner? If so, they may have made some errors doing so.

Fun !!

Bob

[3OnOurWay]

Originally Posted by uncle_bob

If you *do* have a 2021, it would be unusual for it to have come with lithium batteries. Has it been converted from lead acid to lithium by the previous owner? If so, they may have made some errors doing so.

Fun !!

Bob

Great points above. There were a set of 2021 that did have new components including lithium batteries. That doesn’t mean your charger is lithium until you “ trust but verify” on everything.

As UB mentioned when you check battery voltage on battery make sure to check fuses there One battery would set you back but only fuse or sleeping battery would set back your total AH. Doesn’t really account for low voltage issue though

Read about battery posts terminal fuses. You need to check voltage disconnected from all cables on the battery. Turn off house battery first also.

Good luck on a fun Learning experiment

[Stan the Van]

Thanks Bob, I updated my profile to show we have a 2021 AI GT. Still working on the battery/charging issues.

[uncle_bob]

Hi

Ok, so: Do you have one that came "stock" with lithiums or did it come out of the factory with lead acid batteries? Having the original "spec sheet" is one way to work this out. You used to be able to call the factory service folks and they could get you a copy. Does it still work that way? I have no idea .....

Bob

[Stan the Van]

Uncle Bob,
We have a suitcase of paperwork that was given to us from the sellers. Here is what I can find. Our IS GT24 had "4 Deep Cycle Maintenance Free AGM Batteries" as shown on the original window sticker that we found, but it also shows an upgrade at original purchase of "OPT-Lithium Tech Pack, GT" which was $2470.00 back in 2021. We also have a spec sheet of Battle Born Battery Line lithium batteries, is this the Lithium Teck Pack upgrade? I am not sure how to know for sure but we were told it has Lithium batteries.

Either way, the batteries either do not hold a charge overnight or we are not doing something right. Thanks for your help.

[uncle_bob]

Originally Posted by Stan the Van

Uncle Bob,
We have a suitcase of paperwork that was given to us from the sellers. Here is what I can find. Our IS GT24 had "4 Deep Cycle Maintenance Free AGM Batteries" as shown on the original window sticker that we found, but it also shows an upgrade at original purchase of "OPT-Lithium Tech Pack, GT" which was $2470.00 back in 2021. We also have a spec sheet of Battle Born Battery Line lithium batteries, is this the Lithium Teck Pack upgrade? I am not sure how to know for sure but we were told it has Lithium batteries.

Either way, the batteries either do not hold a charge overnight or we are not doing something right. Thanks for your help.

Hi

Ok it sounds like the van came from the factory with AGM batteries. (thus the info on the window sticker). At some point somebody upgraded it to Lithiums. Without actually seeing all the paperwork, that's just a guess. Some of the AS paperwork can be a bit confusing.

Even if the lithiums did come stock, this is pretty early in the history of these conversions. They got a lot smarter about this stuff after the first pass at it.

Any sort of battery setup needs to be looked after a bit. Draining batteries (and kind) to zero and then storing them for a couple years is not a good idea. Since this is a "new to you" van, you really don't know how things got done.

Somebody is going to need to do a deep dive into what's what on the van. There are simply to many possibilities to just guess at this or guess at that. The cost of randomly replacing stuff will quickly get into the "yikes!!!!" range.

What needs to be figured out:

1) How was the charge circuit from the alternator to the house batteries addressed when the lithium's went in? You do that differently with lithiums.

2) How was the shore power charge system modified to handle lithiums? Again, they need (at the very least) different settings than lead acids.

3) What kind of shape are the chassis and house batteries in?

4) Is there some basic fault in the wiring / blown device that's causing an issue? Very much a troubleshooting process.

Each of those items is at least a weekend or two sort of adventure, even if you have all the tools and training.

What is pretty clear is that this needs to get fixed before you do much with the van. When the chassis battery goes out (and it's near dead) you won't be able to start the engine ....

Fun !!!

Bob

[WBB]

Stan,

Sorry you are having these problems, but I will tell you the guys responding to you provided me a lot of help in resolving a problem with my solar charging and were very generous with their time and knowledge. I am far less experienced, but I had a situation two years ago that might provide some insight.

- House Batteries. My Battle Born lithium batteries have a battery management system (BMS) built in that is designed to disconnect the batteries to protect them if the voltage gets too low (below 10.6 volts). This makes your 9 volt reading after disconnecting curious.

I had an experience once when my batteries disconnected (long story) and the van was still reading between 9 and 12+ volts. How?? It was the solar. I was fooled into thinking the problem was not the batteries because I was always working on the van when the sun was shining. It is a long shot, but have you checked the house battery voltage after sunset?

The BMS should reconnect the batteries after you have been plugged into shore power, but if your charger is not set to a high enough voltage, it is possible the BMS will not connect them. Check the battery charging recommendations and make sure your charger is set up correctly. I guess it is possible the settings are not high enough to allow the BMS to reconnect the batteries.

- Chassis battery You may have heard, these vans will discharge the chassis/starter battery in a couple of weeks if the van is not driven and does not get any charge from solar, driving, etc. That is why there is a battery disconnect by the gas pedal (for storage).

The starter battery is a lead acid battery. If the van sat a long time and did not get any charge from solar, etc. there is a good chance the chassis battery was deeply discharged (<12 volts) and potentially damaged. You can try putting a battery charger on it for an "equalization" charge, but it will never be "good as new". Since we buy these vans to go to remote locations, I would lean toward replacing the battery if an equalization charge does not revive it.

These are very complicated electrical systems and there are many things to check, but I thought I would suggest the simplest (potential) solutions. Again, sorry for your issues. Best of luck.

-Bill

[madmac157]

I had the same problem on my 2022 Basecamp 20X with the lithium battery upgrade and 300 watts solar add-on. After troubleshooting at the local Airstream dealer , they discovered the charge controller was set up incorrectly by my original dealer to AGM vs Lithium.

As long as I had plenty of sun and short summer nights, I never noticed a problem. Once the days got shorter and the nights longer, and the sunlight arrived at a less optimum angle, my batteries charged less and less. Eventually, around 4:30 am, all the electrical systems in the trailer would go dead.

I don't know all the details, but either resetting or replacing the controller fixed it.

The Battleborn batteries have a 10 year warranty, so if there are bad cels in your batteries, a replacement should be covered. But I don't think a bad battery is your problem.

[Dick tracy]

Originally Posted by Stan the Van

Thanks, it's a 2021 with lithium batteries. Does appear that the batteries are shot!

Is your charger working? You may only be charging off the TV while in transit.

[3OnOurWay]

Pinging in here, just to check back in with the original poster.


We ran a battery test over the past six days and generator start.

We took our same factory installed system as yours 200 amp hours of lithium batteries in our 24 GL. set the generator auto start at 12.4 volts and generator came on yesterday morning at 7:30 after 6 1/2 days of partial solar charging (nothing over 300 watts) left fridge, vent ceiling fan at 80 * and propane switch on.

We were able to get the batteries down to 18% and 12.5 volts when generator kicked on. We let that cycle off to test that part of the charging system and then put it on shore power.

Set the fridge at medium setting all other power off .98 amp draw fridge off and 4 amps when fridge cycles on.

we use about 20 amp hours / 10% of our battery to have the system run for 12 hours. hope this helps you to give you a baseline in regards to what the OEM Lithium batteries can do for you. Yes we had to reset all since from factory over 3 years ago charging system was not set correctly until Jan 2024

We now know that our bottom end / dead batteries are set at useable 12.5 / 18% we saw the one battery cycle off due to BMS.

We got this idea from another poster. They posted about importance of running a driveway yearly battery test.

[AirFinn]

What a great discussion, so much useful experience flowing around - Tank You!!
So, I have a similar but different problem. Have a 2021 AI GT. A week after I bought it slightly used in 2021 I was T-boned by a spinning Tesla, rear axel and wheels, drive shaft, air-suspension etc destroyed and side panels needed replacing. The whole interior was pulled out the enable the changing of the side panels. It was in the shop for 2,5 years!! Yes!! Ignorance and incompetence by MBZ and Holiday World in Houston. Had to get that out of my system ;-)

So, I suspect that the Lithium batteries were not changed (the chassis battery yes), so they must have gone empty several times in the process. They worked OK for us once we started cruising, but held a charge only for one night, but as a newbie, I did not really know. Now my son took it out last weekend and the house batteries got completely empty, and do not accept any charge. He had shore power connected for 24 hours, and the Magnum Energy panel is the only thing that lights up, (none of the LEDs) and says No Inverter Comm DC 0.0V 0A.
How can I verify that it is the batteries, or could it be something else?

[Boxster1971]

Originally Posted by AirFinn

What a great discussion, so much useful experience flowing around - Tank You!! . . . . . . So, I suspect that the Lithium batteries were not changed (the chassis battery yes), so they must have gone empty several times in the process. They worked OK for us once we started cruising, but held a charge only for one night, but as a newbie, I did not really know. Now my son took it out last weekend and the house batteries got completely empty, and do not accept any charge. He had shore power connected for 24 hours, and the Magnum Energy panel is the only thing that lights up, (none of the LEDs) and says No Inverter Comm DC 0.0V 0A.
How can I verify that it is the batteries, or could it be something else?

Likely the batteries as the Magnum inverter/charger will not work below battery cutoff voltage of about 9-10 volts, depending on the exact settings. Do you have the original lithium batteries, Battleborn I think?

You need to find a way to charge the coach batteries independently. Normally that can be done by disconnecting the batteries and putting each on a charger that will recharge then from zero voltage.

You should also plan to replace the coach batteries as the old ones are likely damaged and will continue to give you problems.

[3OnOurWay]

You can jump the lithiums to wake them up to them place them on a charger 2.0 amp lithium specific charger. If they are from airstream in 2021 likely battle orbs with BMS.
We posted on another thread about this, Battle born has quite a discussion on how to wake up completely dead batteries. Often, the solar should also wake BMS batteries up The Magnum charger will not wake them up ( and it’s probably programmed wrong our was 3 years later) and that’s why jumping them is called for per BB.

Good luck

[uncle_bob]

Hi

(it probably would be better if this was a separate thread ...)

Since you are not the first owner of the van, are you sure it came with lithium's from the factory? If not, then the "lithium conversion" needs to be checked out. Even if it did, the programming of the charger needs to be checked. If it's still set to lead acid (as it may be) that's a gotcha.

If the charger is set to 30A output (who knows where it might be set ....), you have 200AH of batteries. You will need to stay plugged in for at least 7 hours to charge them up (more likely 8 hours).

When in storage, unless you have an aftermarket battery disconnect switch installed, (not just the use/store switch that comes stock) the batteries will drain pretty quickly. Leave that use/store switch in the "use" position and they will drain even faster. A month in "store" is too long. A few days in "use" might be too long (depends on what's turned on ...).

Bob

[AirFinn]

Thanks for all your comments and ideas!! I will get to my van this weekend to check and try out different things. I will report back.