Battery advice

[dlaughlin]

Hi all.

My problem:
My house batteries are bulging and in need of replacement.

My equipment:
Currently, I have four 6V AGM deep cycles by Intimidator. I believe they are less than 5 years old.
I have two Iota DLS-45 converter/chargers.
I have a Freedom control panel.
I have an ‘01 DSDP 4095 on a Spartan Mountain Master chassis running a Cummins ISC 350.

Background info:
We use the RV for vacation only albeit frequently for a working family: 30+ nights/year. When not in use, she is hooked up to 50A service. I leave the chargers on. When we travel, we frequently boondock.

Of note:
I have owned this coach for about a year. When the charge light is illuminated on the Freedom panel, the battery state has always been “bad.” When not charging, it would go back to “good.” The prior owner told me that was normal, I’m not sure the reason he gave me though, although I thought it had to do with the batteries being AGM. Either way, everything always worked flawlessly until our last weekend out when I noticed that I could only start the generator when the coach was plugged in. With the generator running the Freedom panel displayed “Fault.” That prompted me to check the battery bank and that’s when I noticed the bulging.

I plan to get some 6V lead acid batteries from Sam’s Club as they are $88 each. For how we use the coach I don’t see a benefit to replacing with AGM after the 3X coat factor.

Do I need to not charge them all the time? Could there be an issue with the Freedom panel or the Iota chargers? Should I consider deep cycle 12V? Anything else to look for?

Batteries:


Chargers:


Freedom in charge state:


Freedom not charging:

[richard5933]

First, if they are bulging you should get them out of there ASAP. You don't want one to split open and ooze battery acid inside the bay.

One of the ways to kill a battery is charging with too high a voltage. Check the output voltage from your charging system and compare it to the specs in your battery manual. Flooded cell batteries generally have a maintenance/standby charging voltage of about 13.2v-13.5v, and somewhere about 14.5v for the first few hours. If the voltage stays too high for too long it will cause problems.

Flooded cell batteries are cheaper, but they will require more ongoing maintenance to keep them in good shape, including filling with distilled water to the proper level regularly.

[twinboat]

So you have 2 IOTA chargers and a Freedom inverter/charger ?

My guess is that the Freedom inverter/charger, charging section failed and the Iota chargers were added later.
Could be wrong but why have 2 charging systems. Maybe the inverter/charger was added.

If the Iota chargers are the primary chargers, check to see if you have the IQ4 controller and double cable OR the jumper cable is in or out to set the charging voltage.

Here is what they look like. The IQ4 and double cable is what you should have for being plugged in all of the time. It makes the 2 chargers smart 4 stage.


Here is a link to IOTA.
https://www.iotaengineering.com/dls45.htm

[Jim_HiTek]

Boy, that's weird. If your batteries are truly bulged and not just the AGM case design (don't they come with those bulges? I can't remember whether it's AGM or some other type that do).

I'd suggest a battery shop. Scout them out and try to find one that has experience with all the current styles of large batteries. And of course with the room to park an RV.

Some things you can do yourself is ignore that panel, they're often wrong, and get a DVM. Measure the voltage at the battery. I think you'll find it's a bit different than what that panel meter is showing. Also check the users guide for the panel setup...it might have been made for flooded cell batteries, not the AGM's.

Than what I'd do is learn the ins and outs of those Iota chargers. Find the Tech Guide online. Model number right there in your picture. Find out what the failure modes are, find some way to test them. Maybe send them back to the factory for testing.

Finally, there's no need to leave the RV plugged in while you're figuring this out. (Empty the refer if need be). Just disconnect the battery grounds and leave them disconnected. Big batteries like those don't die just because they're not getting charged 24/7...at least if the grounds are disconnected they're not being overcharged either. You can pull them and have them tested too, if you don't want to drive the RV to a battery shop.

BTW, it's not good for most converter/chargers to be operating if the batteries are disconnected so turn them off if you stay plugged into shore power but disconnect the battery grounds. Also the refer won't work without 12 volts.

[dlaughlin]

Originally Posted by richard5933

First, if they are bulging you should get them out of there ASAP.

I plan to replace them this week. We have a cold front coming in tonight and tomorrow so I need to have power to the coach to operate the heater(s). Do you suspect there would be any issue with disconnecting the the 12V system while still connected to 50a service?

[Persistent]

30 battery charge cycles for 5 years is 150 cycles. You should get double that for discharging to 20% SOC and recharging 14 to 18 hours. You should get possibly 600 cycles discharging to 50% followed by 14 to 18 hours of charge.

AGM batteries are sensitive to overcharging. Storing with RV plugged in and coach battery switches "on" should hold the battery terminal voltage at 13.2 volts. 13.6 would be a little high. 14.4 would be way to high and would shorten life. Use your digital volt meter to see what you have.

Bulging batteries may mean the batteries were frozen. Freezing often occurs in freezing weather when batteries are at a low SOC.

All lead acid batteries should be stored fully charged for long life. You store yours while on charge, but the previous owner may not have. Fully charged means 14 to 18 hours of charging.

You can store new fully charged AGM batteries for 6 to 12 months if they are disconnected. Coach battery switches do not always disconnect all appliances. There is frequently a small parasitic load remaining. This will discharge the batteries in as little as 2 weeks.

[dlaughlin]

I’m not sure why I have the Iota chargers. The Freedom Combi appears to be working correctly:


I don’t have an IQ4 controller. The Iota chargers I have are older, no RJ input.

Voltage at the house bank either with the system powered down or “charge on” is steady at 12.18. It stayed the same either on shore power or on generator. The voltage didn’t charge until I started the coach.

Coach batteries were reading 12.06. Obviously those are not being charged.

Gremlins.

[Persistent]

Iota DLS-45 is a constant voltage 12 volt power supply. It is rated to provide 13.6 volts at low currents and 13.4 volts at 45 amps draw. 13.6 is a little high for AGM storage. A little venting could occur, see battery manufacture specifications. It would be fine for flooded cells. In this case water level must be monitored periodically since water will be consumed.

I assume you do not have an inverter in the system. If you do, things get a lot more complicated. There appears to be a battery management system involved. That will also make things more complicated.

When you replace your batteries you should consider getting a smarter converter/charger. You may want one that is drop in replacement for the constant voltage one. I have a WFCO. The WFCO is simple to install and operate. No programming is required.

Get one with a large enough maximum current rating to rapidly charge the batteries you buy. I think 45 amps is good, but a little more may be called for, for 4 6volt batteries (maybe they are 240 to 300 amp hours total). (See battery mfg recommendations.)

The WFCO low battery charging profile starts off rising to 14.4 volts for up to 4 hours. It then drops to 13.6 where it remains while charging or you are using the coach. When full charge is reached and system current draw remains steady for 48 hours, the WFCO switches to 13.2 volts. The 13.2 volts is good for storage for almost all lead acid batteries.

The WFCO does not apply any conditioning voltage spikes so it is good for AGM's. Mfg of flooded cell batteries may specify periodic conditioning spikes. (See Mfg specifications.) In that case a charger that provides the conditioning would be better.

Here is more information about batteries:

Battery University
https://batteryuniversity.com/
How does the Lead Acid Battery Work? https://batteryuniversity.com/learn/article/lead_based_batteries
Summary Table of Lead-based Batteries https://batteryuniversity.com/learn/article/bu_214_summary_table_of_lead_based_batteries
Charging lead acid batteries https://batteryuniversity.com/learn/article/charging_the_lead_acid_battery
GEL https://batteryuniversity.com/learn/article/bu_201b_gel_lead_acid_battery
AGM https://batteryuniversity.com/learn/article/absorbent_glass_mat_agm
How to Charge and When to Charge? https://batteryuniversity.com/learn/article/how_to_charge_when_to_charge_table
How to Store Batteries https://batteryuniversity.com/learn/article/how_to_store_batteries
Summary of Do’s and Don’ts https://batteryuniversity.com/learn/article/do_and_dont_battery_table


There is a lot more. Feel free to browse the index.

[Jim_HiTek]

Originally Posted by dlaughlin

I plan to replace them this week. We have a cold front coming in tonight and tomorrow so I need to have power to the coach to operate the heater(s). Do you suspect there would be any issue with disconnecting the the 12V system while still connected to 50a service?

If you mean any problem with the 50 amp shore power being connected while the battery grounds are disconnected? No, don't think so. At least for the directly connected AC outlets. If there's a bunch of Inverter outlets, you can't use those. As long as the converter/charger (those Iota devices) are properly disconnected or unplugged. Make sure everything 12 volt is off as the converter/chargers will likely overvolt if still plugged in when the batteries are disconnected. With the 120 volt supplied, you'll have powered AC outlets, but you won't have lights because usually those all run on 12 volt. As do all the other devices in the RV. Like the refer control board if it's an RV type.

You won't have the propane furnaces either, or the heat pump if you have one of those. So you'll need several plug in electrical heaters.

I know it's a hassle but keeping the rig warm even without batteries is doable.

[Mr_D]

According to Lifeline it is OK for their AGM batteries to bulge under certain conditions and doesn't mean anything.

[Persistent]

The Iota website says the chargers can be connected in series or parallel so two 45 amp chargers in parallel would be 90 amps.

If the 14.4 volt control plug is installed, it could be the cause of the battery failure. Certainly don't leave it in except when charging. 4 hours in would be the maximum.

The IQ4 module would be good for flooded batteries. Not so good for AGM's. Fully charging and disconnecting would be a good method for using AGM batteries with the Iota or the Iota/IQ4.

[twinboat]

Originally Posted by dlaughlin

I’m not sure why I have the Iota chargers. The Freedom Combi appears to be working correctly:
Attachment 266446

I don’t have an IQ4 controller. The Iota chargers I have are older, no RJ input.

Voltage at the house bank either with the system powered down or “charge on” is steady at 12.18. It stayed the same either on shore power or on generator. The voltage didn’t charge until I started the coach.

Coach batteries were reading 12.06. Obviously those are not being charged.

Gremlins.

Unplug the BTS , battery temp sensor, from the inverter/charger and see if the charging voltages rise. I think I see it in the pucture. They can fail and cause lower or higher voltages then you want. Unplugged is defaults to 78 ° . Its only a test.