Battery Failing Prematurely

[Old_Islander]

I bought a 100 amp hour deep cycle battery about 18 months ago, and it seems to be failing. It will only remain above 12 volts in the camper, for about 12 to 14 hours, with normal camper use. When it was new, it would last for 2 or more days. This is without using the forced air furnace, but water pump, lights, (and all the background circuits -- alarms and so forth...) I generally run the happijacs and slide-out with the truck engine running.

I charged -- then disconnected the battery last fall -- in April it was still very close to 13 volts, so it held it's charge well over winter. I'm wondering if I have a short somewhere in the camper that is sucking the battery down?

How do you measure the resistance of the camper's electrical system? I have a pretty good ohm meter, but don't know what settings to use, or what to look for. I guess I'd check the various systems of the camper, by measuring resistance at the battery cables, by removing all the fuses, and then inserting them one by one, and checking resistance for each?

Is there a definitive test for batteries, that will measure their ability to last under load?

Any advice will be appreciated.

[Harvey51]

And get yourself a battery monitor (amp hour counter) so you always know the per cent of full charge on the batteries. The voltage method is tricky, often reading high because of recent charging. I killed my first set of batteries by relying on it. The second set is doing well after 5 years. I have this $25 eBay.ca battery monitor and it works very well. One hundred watts of solar keeps the batteries always over 80% charge.

[red31]

Ya can check exide (natalus) for their recommended charge profile but a normal charge controller set to flooded usually does a good job, use it in storage to maintain.

http://www2.exide.com/Media/files/Location%20Data/Battery%20Charging%20%26%20Storage%20Specs%20%2011...

[Old_Islander]

MrWizard wrote:

After being fully charged at home, the battery will last the first few nights at an unserviced site without losing much charge. I have a Honda 2000i genny, and charge it about an hour a day, via the camper's built in charger (i.e. the genny plugged into the camper's 110 AC system...). Each day, the battery drains faster, until after a week, I'm charging it twice a day. I suspect this isn't enough daily charge to bring it back to a full charge

this is it, you are not giving the battery enough recharge time
it does not come back to full charge and has been slowly sulphating to death

(1) hour per day is not enough with 'that converter'
you have killed the battery
you will do the same with the new battery, unless you use more/sufficient charge time

Okay, thanks. I suspected this... Hopefully a solar panel / controller will be the fix... I'm looking at a 100 watt panel with an IMP of 5.6 amps...

[MrWizard]

After being fully charged at home, the battery will last the first few nights at an unserviced site without losing much charge. I have a Honda 2000i genny, and charge it about an hour a day, via the camper's built in charger (i.e. the genny plugged into the camper's 110 AC system...). Each day, the battery drains faster, until after a week, I'm charging it twice a day. I suspect this isn't enough daily charge to bring it back to a full charge

this is it, you are not giving the battery enough recharge time
it does not come back to full charge and has been slowly sulphating to death

(1) hour per day is not enough with 'that converter'
you have killed the battery
you will do the same with the new battery, unless you use more/sufficient charge time

[MEXICOWANDERER]

"HAPPIJACKS"
In California nowadays that would be flapjacks with a magic ingredient...

Camper jacks in the saner remaining 49

[time2roll]

Fully charged at home? Did you verify with a hydrometer?
I think you may need an equalization charge.

What converter model does the TC have? Have you checked that it charges at 14.2+ volts on the battery at some point?
I suspect you may have a fixed voltage trickle charge that will chronically undercharge the battery. Also extends the run time for the Honda to charge.

100 to 200+ watts solar will certainly make a difference if you are parked in the sun. Can also make up for a poor converter.

[Old_Islander]

Sorry I have not responded to this sooner... much water under the bridge.

It is a MotoMaster Nautilus marine/rv battery -- a Canadian Tire house brand. It was rated 105 amp hours and wasn't cheap. It's warranty was up in April. Canadian Tire can do a full load test, but I couldn't be bothered to remove it, and transport it to the store and back, just to find out what I already suspect -- the battery's days are numbered.

After being fully charged at home, the battery will last the first few nights at an unserviced site without losing much charge. I have a Honda 2000i genny, and charge it about an hour a day, via the camper's built in charger (i.e. the genny plugged into the camper's 110 AC system...). Each day, the battery drains faster, until after a week, I'm charging it twice a day. I suspect this isn't enough daily charge to bring it back to a full charge. I'll almost certainly be looking for a new battery next spring, so we'll have gotten 2 years out of the Canadian Tire battery.

I'm going to invest in a solar panel & controller, so the panel is charging all day long. This will be good for all future batteries in the camper, too.

And I am working on finding out if there is a parasitic draw within the camper's electrical system, that is causing this to happen prematurely...

Many thanks to all for your advice...!

[BFL13]

SoundGuy wrote:

BFL13 wrote:
He said it has Happijacs in the OP.

And I'd bet that most who've never owned a TC would have no idea what Happijacs are. :R

In that case they would have to work for it, and check his profile:

"9' Okanagan Camper (with slide-out) on 2016 Ford F350 Supercab"

"Camper" is confusing though. Was a thread on that a while back, where it turned out it does not only mean a TC. Some folks call their RVs "campers" no matter what they are.

[SoundGuy]

BFL13 wrote:
He said it has Happijacs in the OP.

And I'd bet that most who've never owned a TC would have no idea what Happijacs are. :R

[BFL13]

He said it has Happijacs in the OP.

[SoundGuy]

Old Islander wrote:
We have a 2-way fridge with tiny indicator lights only. No light in storage area. Water pump is tight -- might run for a second or two, every 4 or 5 hours. Not sure what the emergency brake pin is? This is a slide-in camper on a truck.

What make / model of fridge? Does it have a climate control heating element and if so have you ensured it's turned off, for if not it will significantly draw down your battery reserve. You also need to ensure that any other parasitic draws are turned off, in some cases requiring you to install kill switches, such as in a stereo. Obviously, as a truck camper there won't be any brake system break away switch - but that wouldn't have been mentioned if you'd told us this was a TC. :R

[wa8yxm]

No description of RC or of the Converter.

The Emergency Brake pin is the break-a-way cable the plastic pin on the trailer end of the cable.

IF you have a older RV (I see you've been RVing since 1983, I've been doing it since 1978 and some of those older converters were..... JUNK.

you might have a battery killer

Edit 100 amp hours means a Group 27 or 29. or wal-mart's rating on a 24 (Wal-mart cheats on their ratings read carefully)

Most of these are MARINE/deep cycle. not really deep cycle. you treat 'em like a deep cycle (Take 'em down to 50%) they die young

Try a GC-12.. A bit more amp hours true deep cycle.
Or two GC-2 in series (Six volt two make 12) Lots more amp hours and true deep cycle.

[Old_Islander]

MrWizard wrote:
Do you have a 3 way fridge, rare but still around
Fridge on 12v instead of lp will suck a battery like a vampire
Left a light on in the storage bay?
Emergency brake pin pulled out ?
Water pump cycles a lot ?

We have a 2-way fridge with tiny indicator lights only. No light in storage area. Water pump is tight -- might run for a second or two, every 4 or 5 hours. Not sure what the emergency brake pin is? This is a slide-in camper on a truck.

[Old_Islander]

amxpress wrote:
You might consider performing a parasitic draw test on the system using your multi meter.

Thanks for this... Googled 'parasitic draw test' and found a number of sites with excellent instructions for doing this. I'll try it over the next few days.