Bullet 24RKS batteries

[btallon]

Hi all, I have a 2017 Bullet 24RKS with dual batteries. My first TT. I've had it about 9 months now. Here is my issue. The batteries last less than a day of almost no use. At best with everything turned off but the fridge - which is on gas - I only get a day or two parked in storage. Even overnight when nothing is on but the furnace they are full at night and dead in the morning. The batteries were new when I bought it 9 months ago. Is this normal? Do you think I have a battery issue or is something draining them? And if so, how can I find out what.

[JRTJH]

Take the batteries to almost any auto parts store (AutoZone, NAPA, etc) and they will load test them for you. Leaving any battery on an RV while in storage will often result in a "dead battery in a week". Repeated discharges to that state will shorten any battery life and/or completely destroy any battery in just a few months. So, while the batteries are "only 9 months old" depending on their "terms of service" they may be "dead beyond any hope".

Get them charged, checked and go from there.

[sourdough]

If you've had the trailer for 9 months letting things run, especially the furnace, and discharge the batteries repeatedly, without any maintenance, refilling the water etc. I would bet you just need to buy 2 new batteries and begin a regular mtce. program for them.

As John mentioned, you can have them load tested at a local parts store but even then, not knowing what kind of mtce. has been performed, the performance of the batteries may have been compromised and they can still test OK from my experience.

[btallon]

Maybe I should have said this earlier but this has done this from the start. This isn't a recent development. I have put water in them when they run low. And to be clear I don't let the furnace run all the time. That was only an example of one night where it drained completely with only the furnace running . In storage generally nothing is running But once in a while I will leaveThe refrigerator on if I'm using it 2 weekends in a row.

[JRTJH]

I believe that others have posted something like this:

If a battery is discharged to its "completely dead stage" (0 VDC) that single event can reduce the battery's functional lifespan by 85%. What that means is that if it happened only one time, your battery that "should last 5 years" could only last 15% of 5 years, or 9 months instead of 60 months.

If you've allowed it to discharge to 30% a couple of times, 50% a few times, but only that once was it completely dead, well, you can imagine that 15% could be reduced to significantly less than the "expected 9 months"....

[Logan X]

I didn’t see if someone else mentioned this already, but your trailer will always be drawing “phantom loads” from the battery, even if everything is off. If you have stored the trailer with the batteries connected, with no charge going to them, they are most likely dead and not coming back.

The good news is it’s not that expensive of a mistake and lots of people have made it, including me.

My suggestion is to not let the batteries get below 60% state of charge and use a quality battery monitor to know what your state of charge is.

Good luck!

[Customer1]

Something you may not be aware of is draining the batteries. It is going to take some detective work. Batteries last years, not months.

You aren't using the breakaway as a parking brake are you?

[btallon]

Something you may not be aware of is draining the batteries. It is going to take some detective work. Batteries last years, not months.

You aren't using the breakaway as a parking brake are you?


No, I am not. Thank you.

For the others, I'm not sure, other than disconnecting them, how to keep the batteries from discharging when they discharge overnight (and always have). I understand what you're saying about not letting them get to 0, but not sure how to stop that if they discharge so quickly.

[sourdough]

No, I am not. Thank you.

For the others, I'm not sure, other than disconnecting them, how to keep the batteries from discharging when they discharge overnight (and always have). I understand what you're saying about not letting them get to 0, but not sure how to stop that if they discharge so quickly.


What are you doing with the RV/batteries? Why are they connected and running all the time if you aren't using the trailer? Can you connect it to power so the converter can charge the batteries? If not, why can't you disconnect the batteries and put them on a battery tender?

Whether they were new or not 9 months ago, by your description I would highly doubt that they are in very good shape now.

[flygrimm]

Seems to me that the original question is why do the batteries discharge almost completely overnight. Been doing this since new.

My trailer has a single battery and will discharge in 4 or 5 days if left disconnected from shore power. There is always something running even with all the usual things turned off.

Several things run even when the trailer is dark. The converter, CO2 detector, radio and a few other things I can't think of right now.

I would charge the batteries and take them to Auto Zone or some other such place and have them checked. They have to be fully charged for this. If they check out OK or not I would then hook up the batteries (original or new) and hook up an ammeter between the positive cable and the battery terminal and see what your drain is. It should be a pretty small number. If not then I would start pulling fuses one at a time until the suspect circuit is found. There may be a defective unit of some kind or even a short.

Stuart

[German Shepherd Guy]

Hi btallon.
Sounds like your batteries are kaput.

As John said have them load tested, and then most likely replace.


As for the drain.... Not easy to find. There are a few "phantom" loads in a new trailer but unusual for them to drain a set of batteries overnight. So that makes me believe your batteries were bad from the git-go. Maybe dealer had left them drained too many times, whatever.


After getting new batteries you might want to consider a dis-connect. This is the one I use but there are many types and all do the same thing.


https://smile.amazon.com/Ampper-Battery-Disconnect-Isolator-Vehicles/dp/B07JZ9NDH2/ref=sr_1_5?crid=RCL9CHWCYR9J&keywords=battery+disconnect+switch&qid=1571051826&sprefix=battery+dis%2Caps%2C1145&sr=8-5


That way there is no drain on the batteries when not in use.


Good luck. Hope that helped.

[SteveSykes]

One thing no one has suggested, with the batteries fully charged from shore power, insert an ammeter in-line with the positive battery cable. Unplug shore power to see what the current draw is. Compare that number with the capability of the batteries. That will tell you how long you can operate just from batteries.

Steve

[MarkEHansen]

Another thing to consider is the type/size of the batteries being used. Most dealers install the cheap, dual-use marine battery, which is not that great. If you're going to replace the batteries, you may want to consider full deep cycle batteries.

As others have eluded to, you really can't leave your batteries with your trailer while in storage, unless you have shore power connected. You should consider taking the batteries home and connecting them to a battery tender when they are not in use. This will help greatly in keeping them charged and in good condition.

There's a lot to learn about RV batteries, so don't be afraid to ask. Lots of advice/help here.

[Ken / Claudia]

Did you read this yet, get the batteries tested. Replace if bad which is my bet.
If there OK or good keep them. Which ever is the answer regarding that, come back on here for advice. Saying the batteries did that from the start months ago does not matter right at this time. You, me and everyone else on here has no idea if they were good to start with. Let's start now with batteries that are 100% known good. Than many on here can advise on steps to take to check power draws, power issues, storage, charging and maintaining them.
Finally if your replacing the batteries, make sure the salesman knows you need batteries for RV use. If any questions about which batteries are best. That can easily covered on here also.

[Bamabox]

If your batteries are in fact dead, you might want to consider going 2 6V golf cart batteries. Lots of posts on here about that. I did it early this season. 2nd best upgrade after a better mattress :).

[Phil Saran]

One other item not brought up yet is are they Deep cycle RV batteries or car batteries?

On this or another forum one guy bought a TT and the dealer put a car battery in it.

Just something else to check. Plus always top off batteries with distilled water not
tap water.

[GvS]

Once you determined the cause of the batteries not holding a charge you may want to consider keeping your trailer plugged in when not in use if you're not going to pull your batteries. Keeping it plugged in works to trickle charge them and keep them from draining to zero. I rarely replace any battery if its kept on a trickle charge.

[crowbar]

Last time I replaced batteries I went to the 2 golf cart batteries. Took them out in winter and kept them charged up in the garage. Still, to my dismay, after just over a year, they wouldn't hold up more than a day when dry camping. Had them charged up and tested at a shop where I deal and they found that one of the batteries had a bad cell. Knowing that your batteries are only as good as the worst one in the series, I bought another battery as the warranty for this particular battery is only 1 year. Now after another season of camping, I can go for days of dry camping with no problem, even though one of my batteries is still the original (old) one. Sometimes you just end up with a lemon and this could be your experience here.

[skids]

I would be inclined to just replace the bad one also. Too expensive to replace both!

[chuckster57]

I would be inclined to just replace the bad one also. Too expensive to replace both!



If the batteries are different in age, they should be replaced as a pair.


https://www.optimabatteries.com/en-us/experience/2014/04/can-i-connect-dissimilar-batteries-parallel

[tanglemoose]

Batteries should last much longer. If you have a TV there is a small button by the connection inside RV. If that is on, it will run your batteries down.

We have solar panel and have had our batteries 3 years... they don't allow batteries to draw down...

[travelin texans]

I would be inclined to just replace the bad one also. Too expensive to replace both!

You should never mix old with new batteries, the weak older ones will drain the new one. Always replace with matched sets of like batteries.

[skids]

You should never mix old with new batteries, the weak older ones will drain the new one. Always replace with matched sets of like batteries.

Is this true for charging 6v batteries in series and for 12v in parallel?

[JRTJH]

Is this true for charging 6v batteries in series and for 12v in parallel?

Yup.

When you consider it, two 6 volt batteries (3 cells each) connected in series (3+3=6) is electrically the same as one 12 volt battery (6 cells connected in series). Mechanically, they are different because the cells are divided into two "containers of 3" but electrically, they are essentially the same....

So, just a a "single bad cell" can destroy a "6 cell 12 volt battery housed in one container", a "single bad cell can destroy a "6 cell 12 volt battery that's housed in two separate containers"

The difference is, even if you catch a bad cell in a 12 volt battery, you have to replace the other 5 cells...

In two 6 volt batteries, if you catch the bad cell soon enough, you only have to replace the two cells contained in the same box... You "SHOULD" replace the other box of 3 cells, but it may/may not remain undamaged and may/may not remain functional with a replacement of the battery with the bad box....

It's the same as with two 12 volt batteries in parallel. You may/may not get lucky and not see any damage to the other box of cells....

BUT: without regard to "luck", 6 cells in two boxes "interact and can be damaged" if connected in series just as easily as 6 cells in the same box "interact and can be damaged" They also are connected in series.

Having four 6 volt batteries, in series/parallel arrangement would effectively be the same as two 12 volt batteries in parallel. No matter if there are two 6 volt batteries or four 6 volt batteries or eight 6 volt batteries, just like their "12 volt brothers" they all interact electrically and one bad cell can damage the other 5 or 11 or 23 or .... cells in that circuit......

[flybouy]

With multiple batteries and a "single source" for charging all batteries in that battery "bank" should be replaced at the same time. If one battery is defective the charging source "sees" this as one battery and can overcharge the good battery while attempting to charge the bad one. The results will be a weakened or destroyed "good" battery. There's no way to "balance" the charge rate between the 2 batteries without an elaborate, expensive charging and battery isolating system. The cost of that system is only economically viable if you have a solar array or a very large battery back up system with a lot of batteries.
In simplest terms do you replace one shoe at a time or get a new pair?