Battery Issue

[Lamokadave]

Did some battery maintenance today on our new to us 2021 Omni XG32. I found ea of the 4-6v batteries to be dry on top with 2 of the batteries taking over 64OZ of water. Ea battery is showing 6.5-6.6v after being disconnected from the converter of at least 1 hr.
We did use the MH for a 2 day shakedown last week. We were plugged in most of the time but did unplug for over an hr to test the inverter. I never saw battery voltage drop below 12.6 although our solar panels were putting out approx 6 amps.
I plan to check the voltage in the morning along with sp gravity. I was planning to take the batteries to an auto parts store for a load test.
Im trying to decide if these batteries are toast and need to be replaced. If they pass all the test tomorrow, can I trust them or is it a lost cause?

[lwmcguir]

Your voltage was good

Load test will tell

[16ACE27]

Their life is maybe shortened but they will probably be OK. You can buy a cheap ($20) 100 amp load tester at Harborfreight; easier than hauling out 4 batteries:

https://www.harborfreight.com/100a-6...ter-61747.html

They also have a 500 amp tester for $50.

[DavidEM]

Whatever part of the plates were exposed to air are now ruined. For example if 25% of the plate height was above the electrolyte you now have 75% left, probably less. Time to replace them.

An auto parts store load test will tell you if they will start something, not what their amp hour capacity is. You can pass this load test but still have very damaged batteries.

The only way to know is to put a significant, 20 amp load and see how long it takes for them to run down. It should take about 20 hours for 4 good GCs to run down to zero with a 20A load.

David

[chunker21]

I'm going to assume that you did not check the battery levels before this. Not unusual as it's a bit awkward to get the caps off. You also said "new to you" so how long had the RV been in service before you took possession? I ask that so you will know if the water loss was a rapidly developed issue, or perhaps long term from evaporation? After I got mine one, new and new to us, in May I did check the batteries and had to rearrange the cables a bit to get the caps off. As 16Ace suggested a cheap load tester can be found. I got an expensive one, well twice what HF charges, at an Advance Auto out west a few years ago when I had battery issues on a trip.

Me?? I'd make sure the batteries had good water/electrolyte levels, charge them good, perform a load test, and as long as you have good readings, go with them. Do the batteries themselves have a date sticker on them?

[Lamokadave]

Originally Posted by chunker21

I'm going to assume that you did not check the battery levels before this. Not unusual as it's a bit awkward to get the caps off. You also said "new to you" so how long had the RV been in service before you took possession? I ask that so you will know if the water loss was a rapidly developed issue, or perhaps long term from evaporation? After I got mine one, new and new to us, in May I did check the batteries and had to rearrange the cables a bit to get the caps off. As 16Ace suggested a cheap load tester can be found. I got an expensive one, well twice what HF charges, at an Advance Auto out west a few years ago when I had battery issues on a trip.



Me?? I'd make sure the batteries had good water/electrolyte levels, charge them good, perform a load test, and as long as you have good readings, go with them. Do the batteries themselves have a date sticker on them?

The MH just turned a year old( original purchase date). We've had it a month but most of that time was at the Ford dealer and then a THOR dealer to get some things fixed/ evaluated, before the warranty expired ( including possible cap separation). Original owner was either clueless or just didn't care about several nuisance items.
They did dry camp allot so added an additional 100w panel and an additional 210 amps of battery. I'm not sure what batteries the MH came with, but it now has 4- 6v Rocket L-605. They're Korean (Sebang Global). They're rated at 175a/5hrs, 210a 20hrs. I really don't understand that rating but think of them as 210a.
2 of the batteries took over 64oz of water so I'm assuming they are the originals and never saw any care. The 2nd 2 were dry just below the top so I think they were the added pair. The 2 drier after sitting 12+ hrs are now read 6.33v . The other 2 are still in the 6.5,v range. As suggested above, maybe I need to put a constant load on them and see how they degrade.

[DavidEM]

The standard for rating deep cycle batteries capacity is C/20 which means if you drain them at 1/20 of the batteries rated capacity they will last 20 hours until dead. Some manufacturers also quote C/10 or C/5 but C/20 is the standard and is closer to how we actually use RV batteries.

Sounds like your first two batteries are really dead and the newer two might have some decent life in them. You might test them in pairs by disconnecting the new ones and draw the old ones down at 10 amps (C/20) and see how long they last. Then if no good test the newer ones and see how long they last. Anything better than 15 hours I would reuse them.

David

[lwmcguire]

Originally Posted by Lamokadave

The MH just turned a year old( original purchase date). We've had it a month but most of that time was at the Ford dealer and then a THOR dealer to get some things fixed/ evaluated, before the warranty expired ( including possible cap separation). Original owner was either clueless or just didn't care about several nuisance items.
They did dry camp allot so added an additional 100w panel and an additional 210 amps of battery. I'm not sure what batteries the MH came with, but it now has 4- 6v Rocket L-605. They're Korean (Sebang Global). They're rated at 175a/5hrs, 210a 20hrs. I really don't understand that rating but think of them as 210a.
2 of the batteries took over 64oz of water so I'm assuming they are the originals and never saw any care. The 2nd 2 were dry just below the top so I think they were the added pair. The 2 drier after sitting 12+ hrs are now read 6.33v . The other 2 are still in the 6.5,v range. As suggested above, maybe I need to put a constant load on them and see how they degrade.

Voltage indicates the batteries are very usable

Unless you're a hard core boondocker just use them and see how they perform

Are you familiar with 6v battery voltage charge charts?

6.38 is about the best a new battery will hold 24 hours

I don't know your charger but they need charged on one capable of desulphation to help them recover as much as possible

Sent from my SM-G970U using Thor RV Forum mobile app

[HMCSW]

Originally Posted by Lamokadave

Did some battery maintenance today on our new to us 2021 Omni XG32. I found ea of the 4-6v batteries to be dry on top with 2 of the batteries taking over 64OZ of water. Ea battery is showing 6.5-6.6v after being disconnected from the converter of at least 1 hr.
We did use the MH for a 2 day shakedown last week. We were plugged in most of the time but did unplug for over an hr to test the inverter. I never saw battery voltage drop below 12.6 although our solar panels were putting out approx 6 amps.
I plan to check the voltage in the morning along with sp gravity. I was planning to take the batteries to an auto parts store for a load test.
Im trying to decide if these batteries are toast and need to be replaced. If they pass all the test tomorrow, can I trust them or is it a lost cause?

It is a PITA to get to the batteries. Check out Flow-rite. I now fill the 4 batteries in about 30 seconds. Awesome products.

[Lamokadave]

Originally Posted by DavidEM

The standard for rating deep cycle batteries capacity is C/20 which means if you drain them at 1/20 of the batteries rated capacity they will last 20 hours until dead. Some manufacturers also quote C/10 or C/5 but C/20 is the standard and is closer to how we actually use RV batteries.

Sounds like your first two batteries are really dead and the newer two might have some decent life in them. You might test them in pairs by disconnecting the new ones and draw the old ones down at 10 amps (C/20) and see how long they last. Then if no good test the newer ones and see how long they last. Anything better than 15 hours I would reuse them.

David

I actually did something similar today and conclude the very dry 2 are toast but the other 2 are usable. I paired the 2 suspicious in series and connected a 120vAC fan through a 300w inverter. After 2.5 hrs running continuously, the running voltage was down to 11.8. I turned off the inverter and the batteries recovered to 12.06. I consider this near dead. I then did the same with the other 2 batteries. After 3 continuous hrs the running voltage was 12.46 and after shutting down they jumped to 12.57. These 2 are healthy. We do boondock frequently enough where significant battery power is required considering we have a residential fridge. Battery access is very difficult so maintenance is difficult to do requiring major work. I just ordered 3 Renogy 100a lithiums which yields more usage power and virtually eliminates the maintenance hassels

[Hugh.vines@att.net]

Originally Posted by Lamokadave

I actually did something similar today and conclude the very dry 2 are toast but the other 2 are usable. I paired the 2 suspicious in series and connected a 120vAC fan through a 300w inverter. After 2.5 hrs running continuously, the running voltage was down to 11.8. I turned off the inverter and the batteries recovered to 12.06. I consider this near dead. I then did the same with the other 2 batteries. After 3 continuous hrs the running voltage was 12.46 and after shutting down they jumped to 12.57. These 2 are healthy. We do boondock frequently enough where significant battery power is required considering we have a residential fridge. Battery access is very difficult so maintenance is difficult to do requiring major work. I just ordered 3 Renogy 100a lithiums which yields more usage power and virtually eliminates the maintenance hassels

Will they car with your alternator without ac dc charger

[16ACE27]

Originally Posted by Hugh.vines@att.net

Will they car with your alternator without ac dc charger

Translation anyone?

[Trophy1200]

Originally Posted by 16ACE27

Translation anyone?

Charge?

[16ACE27]

Originally Posted by Trophy1200

Charge?

Could be: Maybe; "Do the batteries charge from the engine alternator?"

[dkoldman]

Originally Posted by 16ACE27

Translation anyone?

Dijo ¿Se cargan las baterías desde el alternador del motor?

[Chateau_Nomad]

هل سيقودون السيارة مع المولد الخاص بك بدون شاحن تيار متردد

[Lamokadave]

My take is will they work without using a DC to DC charger.

Yes and no. it would not be optimal as the charging profile directly from the engines alternators is not correct for lithium. The batteries recharge rate is not optimal for the alternator. I will eventually include a dcdc charger.
Would things be in some way workable without the charger??
yes

[Lamokadave]

Originally Posted by DavidEM

The standard for rating deep cycle batteries capacity is C/20 which means if you drain them at 1/20 of the batteries rated capacity they will last 20 hours until dead. Some manufacturers also quote C/10 or C/5 but C/20 is the standard and is closer to how we actually use RV batteries.

Sounds like your first two batteries are really dead and the newer two might have some decent life in them. You might test them in pairs by disconnecting the new ones and draw the old ones down at 10 amps (C/20) and see how long they last. Then if no good test the newer ones and see how long they last. Anything better than 15 hours I would reuse them.

David

I likely will reinstall at least 2 of these batteries for our next short trip at least until i get the new lithium set up designed and installed. W'ell be dry camping for 4 days. Am I better off not putting the 2 weaker batteries back in the mix and just rely on the 2 stronger. i fear the weaker may draw down the stronger

[DavidEM]

Since you have just invested significant money in lithium batteries, I would invest maybe $100 more for the tools to maintain and use them well.

The first is an inexpensive shunt based battery monitor. QWorks makes a good, cheap one available on Amazon for about $40. It lets you see current amperage in or out of the batteries and cumulative amp hours in or out.

The other is a clamp on DC ammeter, also available from Amazon for $75 or less. This lets you measure individual device current flow. For example use it to measure the current going from the alternator to the new batteries, particularly when the batteries are well discharged. In that case the alternator's fixed voltage of about 14 volts may supply enough current into the discharged lithium batteries to overload your alternator.

I think anything over 50 amps would be cause to worry.

David

[Lamokadave]

This project is close to wrapping up. I've determined that 2 of the 4 batteries are usable in the short term. Only remaining question is do I need to add battery acid to bring the spg into range. I ran a continuous 10A load on them for 3 hrs yesterday with only a small drop in voltage. My original hydrometer test on these was between 1125 and 1150 suggesting weak cells however the battery easily survived the test. I tested today after an overnight recharge and the spg is between 1150 and 1175.
Should I replace some of the water with battery acid to correct?