Battery recharging/maintenance

[John K.]

We have a 2012 JayFeather Ultralite x20e. Its battery, an Interstate deep cycle SRM-24 is more than 4 years old and appears to be over the hill. It could not keep our trailer freezer cold enough while sitting for 24 hours w/o shore power. I've read online that 3-4 years is the average life for an RV battery, but that can be extended with proper charging and maintenance. I read online that charging should be done when the battery state of charge is less than 80% and that when the RV is stored for awhile, the battery should be tested and charged monthly (I keep our battery in the basement during the winter). The online source recommended using a multi-stage converter/charger, some costing $150-$300, and voltmeter, $8. Replacing the SRM-24 will cost $160. It seems the investment for a converter/charger and voltmeter is well worth it over the long run if I can double the life of the battery from 4 to 8 years. I also read about gel and absorbed glass mat batteries, which are supposed to cost more but last longer and don't tolerate fast charging. We rarely rely on the battery for power, but we have stored our Jayco overnight at some places w/o shore power and need the battery to keep the refrigerator/freezer and other items working.

Any thoughts?

Any recommendation for a brand/model of new battery to buy?

Is a gel or AGM worth the extra cost?

How about a recommendation for a converter/charger?

Would a Battery Minder low amp/charger be worth it in my situation?

Thanks for any and all help!
John K

[Mustang65]

John,
You are one of the many trying to figure out what to do about the battery(s) powering the fridge. The battery that comes with the TT's is the low-end model. Pretty much to cover the legalities of having a battery to operate the brakes on the TT should they be needed and keep the lights on for an evening. To keep your fridge going for 24 hours, without Shore-Power or SOLAR is almost impossible with the basic battery, without the battery voltage dropping below the 12Volt level. As for how long batteries last, there are toooo many variables that have an effect on the batteries life cycle. I am on year 4 for my 2 Trojan T-145 (6 volt 260Ah) batteries, which meet our needs.

To accomplish your goal of getting 24 hours of fridge running time, without killing your batteries, you will need to upgrade to (2) 12 volt 100Ah batteries (wired in parallel, for 200Ah) or (2) 6 volt batteries (like the Trojan T105 220Ah) batteries and they will need to be fully charged to make it through the 24 hours.

Unless you have a specific reason for going with AGM or other batteries, like an enclosed area, I would stick with the regular flooded Deep Cycle batteries. They are less expensive and do a great job. True Deep Cycle batteries can be identified by NOT having a CCA or MCA cranking rating.

I can not help you with the type of battery charger as I have SOLAR and it keeps the batteries topped off all year long. I am sure some of the other members can give you a little help in this area also.

Don

[howlin4you]

I'm confused, are these 12 volt refrigerators and not LP? I can easily run my fridge for days using the stock interstate battery and propane.

[John K.]

The refrigerator can operate on the 12v battery, LP or shore power. We rarely want to use LP. Our Interstate battery recently couldn't keep the refrig/freezer cold enough after 24 hrs sitting in a driveway. That suggests to me that it needs replacing.

[Mustang65]

Originally Posted by John K.

The refrigerator can operate on the 12v battery, LP or shore power. We rarely want to use LP. Our Interstate battery recently couldn't keep the refrig/freezer cold enough after 24 hrs sitting in a driveway. That suggests to me that it needs replacing.

John,

What is the mfr/model of your fridge?

Don

[tbwill]

Originally Posted by John K.

The refrigerator can operate on the 12v battery, LP or shore power. We rarely want to use LP. Our Interstate battery recently couldn't keep the refrig/freezer cold enough after 24 hrs sitting in a driveway. That suggests to me that it needs replacing.

Any particular reason not to use propane? The 12V operation on 3-way refrigerators is by far the least efficient way to cool. The Norcold/Thetford specs says it draws 14.8 amps in 12V mode, that would drain any battery pretty fast. If you use propane it only draws 1.2 amps to keep the controls and igniter working. The manual also states: "DC electric operation is less efficient than AC electric and propane gas. Use DC electric operation only to maintain the refrigerator temperature while in transit and if the other energy sources are not available. Do not use DC electric to initially decrease the temperature of the refrigerator." I would use propane if 120V is not available, much more efficient.

[John K.]

Thanks to everyone who responded on my battery question. I learned a good amount about the topic. I plan to rely more on propane than the battery in the future.

However, I still need a new battery. Does anyone have suggestions for a brand/model? How about for a converter/charger?

Thanks again to all!

[BCK]

Lots of opinions. I had 2x 6V on my last trailer. On our last trip with the TT we dry camped for 6 nights on the 10yr old batteries and still had life in them.

Costco (Canada) has a 12V deep cell marine battery rated at 190AH that I'm keeping in mind for when the stock battery on our new TT needs replacing.