New Batteries Again?

[Ejs4029]

Originally Posted by bikendan

I don't consider Interstate to be a premium brand, especially since most Interstate batteries installed on RVs, are basic dual-purpose marine batteries. These are not true deep cycle batteries.

I can't complain my 2016 Rockwood had an Interstate SRM-24 installed by the selling dealer and it lasted me 6 years Served my purpose just fine.

[bikendan]

Originally Posted by Ejs4029

I can't complain my 2016 Rockwood had an Interstate SRM-24 installed by the selling dealer and it lasted me 6 years Served my purpose just fine.

I had the same battery but we dry camp and boondock some and it couldn't keep up. It's fine if you always have electric hookups.

[Chaplain Kent]

Yes, motorhome wiring is complicated. On our trip we had to use the by-pass switch to start the generator. This switch was stuck open thus giving 12 volt power from the engine starting battery even with the house batteries removed. I have repaired this switch. We did get a refund from Interstate for our fourteen month old batteries. I replaced the Interstates with two of the largest Ever Start batteries they make. I found out they are made by a quality Milwaukee company, Johnson Controls. I will use my fancy $9.00 battery shut off after the batteries are charged. I will no longer trust the by-pass switch; however, I do have a question. If this by-pass switch is stuck open does it also allow charging the house batteries from the alternator when we are driving?

[jd4010]

Originally Posted by TitanMike

I eventually eliminated my "water problem" (as well as all battery maintenance issues). I installed two LiFePo4 batteries and am haven't looked back

Curiosity got to me and I looked up Lifepro4. Holy battery Batman! The 100Ah is over $1k and some go to $2700. EEEEKS!

[Retired JSO]

I’m not a mechanic so I don’t mess with much. We own a 2018 Cardinal. When not traveling, it is plugged in 24/7 and still using the original 2 no name batteries.

[bbells]

Are you using interstate marine batteries or true deep cycle batteries? If marine that is about how they work

[Papadave]

I was at Costco checking out some great prices on batteries and I think they were interstate. The clerk said that those were the “one year warrantee” ones. I asked how long they might last and he replies “one year if you are lucky” I assume they are prorated over that period. Like most of you, I have been comfortably getting 3 to 5 years out of a group 27 “Marine grade “deep cycle. I question whether you can do that these days. I would have to guess that they’re importing lower quality batteries and slapping a sticker on them. Working with lead and sulfuric acid probably has less regulations in other countries.

[MNtraveler]

Originally Posted by Chaplain Kent

I have just burned up another pair of expensive batteries. I always thought the switch by the door was a battery off switch but no it is not. The switch turns off all 12 volt even with the converter running and plugged into shore power. What use is a switch like this? I am now trying to take out the waste can cabinet floor to see how this is wired. Is it possible to make that switch a real battery shut off?

Leave that switch on until you put the unit in storage. And then you will aos need a "real" disconnect switch to take every possible load off the batteries, even those that bypass the so-called "on/off" switch.

With that switch off you cannot use the 12V system in the RV, i.e., lights, 12V fans, 12V TV if it's 12V, etc. So just leave it on. That isn't the issue.

Over charging might. be the issue. Requires testing and troubleshooting.

Our 2016 has its original batteries installed in 2015 (for model year 2016) and we're about to put it into our 7th full season. They still charge up to full and give good usage.

[MNtraveler]

Originally Posted by jd4010

Curiosity got to me and I looked up Lifepro4. Holy battery Batman! The 100Ah is over $1k and some go to $2700. EEEEKS!

That'll be the day . . .

[MNtraveler]

Originally Posted by MR.M

The converter should supply 12V right to the 12V fuse panel . look for burnt 30 or 40 amp fuses on panel and on converter you should not need battery if on shore power . check the voltage from the wires are the converter and where the wires go to the fuse panel.

Even when on shore power all 12V lights and accessories are powered off the batteries and the converter continues to replenish the batteries, so it's a continuous live circuit. If you turn "off" the batteries, the 12V system will go down inside the unit.

[mnoland30]

Interstate does sell a 12v "deep cycle" marine battery. They are expensive, at around $180. They are a dual purpose battery, not exactly what you want for an RV. You can buy two 6v golf cart batteries for around $90 each and wire them in series. They are miuch better than a dual purpose battery. If you're going to boondock, definitely buy a battery monitor with a shunt. It tells you exactly what is going into and out of the battery. You will know in short order what is wrong. Solar panels with charge contoller will help to keep your batteries from being discharged too far. It also gives the slow chage that batteries need to get the last 10% of charge.

One cell going dry, does sound like a warranty issue to me.

Check out this link for voltage and state of charge information.
https://www.rvtechlibrary.com/battery/bat_volts.php
The problem with just using a voltmeter is that the only accurate measure is when the battery is rested for a few hours. Measuring while under load, or soon after will underestimate the voltage, and measuring right after charging will overestimate.

[moose074]

Originally Posted by Papadave

I was at Costco checking out some great prices on batteries and I think they were interstate. The clerk said that those were the “one year warrantee” ones. I asked how long they might last and he replies “one year if you are lucky” I assume they are prorated over that period. Like most of you, I have been comfortably getting 3 to 5 years out of a group 27 “Marine grade “deep cycle. I question whether you can do that these days. I would have to guess that they’re importing lower quality batteries and slapping a sticker on them. Working with lead and sulfuric acid probably has less regulations in other countries.

I have never been to a Costco, but I assume they are a lot like Sams. When I go to Sams, wal mart even an auto parts store. I go fully prepared. Especially now days, oriellys required a knowledge test it was like 20 questions very basic 10 years ago when I worked there part time. The manager gave it to me said she would be by to help me with it shortly. I was done with it in less than 5 minutes, she claimed I was one of the few at the time that passed without help. We now have an oriellys in my home town so no driving. It’s a good chance that when I go in there needing help there isn’t going to be anyone that can except to go through the motions of tapping keys. My experience at big retail is the same occasionally there will be a knowledgeable person but rarely. They are taught enough to get thru the shift if you will. Like my manager from oriellys said those that have the knowledge to work there and want to work are making $25-30 an hour in the oil field not looking for a $8 hour job

[JimM2109S]

Originally Posted by jd4010

Curiosity got to me and I looked up Lifepro4. Holy battery Batman! The 100Ah is over $1k and some go to $2700. EEEEKS!

There are many LiFePO4 100Ah batteries made by quality manufacturers that can be bought for under $400 each. William Prowse on YouTube has probably fifty or more videos where he has made independent tests on various brand and size lithium (LiFePO4) batteries. Two of the lesser cost brands that he has recommended are Chins and AmpereTime, both available on Amazon. Note that these lesser cost lithium batteries usually do not include a low temp cuttoff, 32F, and charging a lithium that is at or below 32F will damage the battery. They can still power loads down to about 0F but should not be charged at temps below 32F.

Also consider the life of a lithium battery. They are good for an estimated 4,000+ cycles at up to 80% discharge, probably 10x that of an AGM/Flooded Cell battery. They are basically a "buy once, cry once" purchase.

[TitanMike]

Originally Posted by jd4010

Curiosity got to me and I looked up Lifepro4. Holy battery Batman! The 100Ah is over $1k and some go to $2700. EEEEKS!

Yes, some can be expensive but there are a lot of selections at lower prices.

When I bought two Battleborn's for $1600 total. That was in 2019 and have no expectation of replacing them before 2035, if even then.

Today the prices are down to as low as <$400 for a 100 ah LiFePo4 battery. Not much more than a premium AGM battery at twice the weight and half the usable power.

[TitanMike]

Looks like I type slower than Jim[emoji16]