Well I've gone and done it. I pulled my group 27 marine yesterday evening to move it to the boat in preparation to catch some spec's ahead of the storm blowing in today. I use this battery on my trolling motor as well as the camper. I thought I had my battery disconnect switch off for the last six weeks or so but I left it on. My WFCO boiled out my 6 1/2 year old battery (date code 06/10). She lived a good, long life but I murdered her.Now I'm here with the day off, not going fishing with some time on my hands. I decided to fabricate an inline charger timer. A PCB mounted in-line between the pos cable and battery. This is just to maintain the battery, not charge it when depleted. I'm thinking program it to charge 1 hour every 24 hours. I reach out to the WLA battery experts here. Is 1 hour on, 23 hours off a good profile to maintain without harming my new not yet purchased group 27 marine hybrid or can you recommend a better profile? I have been leaving it on for 2 days and off for 5 but after so many years that's getting old. I'm looking for a better way without replacing the WFCO.

My single mode charger boiled out one of my batteries in about three weeks. This was only putting out 13.6VDC...Now I have a smart mode PD9260C Converter/Charger which puts out smart mode charging DC voltages...This does the 14.4VDC - 13.6VDC - 13.2VDC and once every 19 hours will run about 15 minutes putting out 14.4VDC...I use to watch my batteries after installing this unit but always found them in good shape...It does everything automatic now when I leave it running off of home shore power...Here lately however I have been doing a complete disconnect on my stored batteries and if they start out being fully charged then and reading 12.7 or so VDC just sitting there they will very slowly start dropping their charge.Over the winer months it will take a couple of months for them to get from the 12.7VDC to the 12.5VDC readings. When I see that I will connect the batteries and turn on the PD9260C converter/charger again to bring them back to their full 100% charge again...I have one GP24 battery setting here in my radio room that has been sitting here in a box disconnected and reads 12.6VDC and will occasionally flicker down to 12.5VDC... I can switch in my standby 600WATT PSW Power Inverter and it will run a couple of 120VAC emergency lights for hours... This is my last good GP24 12V 85AH battery from my original battery bank here.I am currently in the planning stage to redo my trailer battery bank using two groups of T105 6V batteries in series to give my a good 450AH capacity 12VDC battery bank... Just about got my metal battery box all drilled out and fitted with BLUE SEA Switches, meters, and lug terminals components for monitoring and distributing my 12VDC power requirements. Waiting for money to purchase my Trojan T105s Batteries from a local golf cart dealer here where I live... This will all mount on my trailer tongue area in a 58-inch Torklift Battery box with top slide where my older 12VDC interstate set in plastic battery boxes... Gonna be a Perfect Fit within the one inch welded on Battery tray angle guides...Roy's imageRoy Ken

Thanks for the reply RoyB but I'm not sure this answers my question.My concern is stratification and scaling. As mentioned, I have been applying a 13.6V - 13.8V charge (whatever the WFCO feels like doing that day) for 2 days and removing it for 5 days and repeat. I would equalize them about every 6 months or so. This seemed to work fine for years but I don't know of a method to gauge or quantify stratification or scaling. It appeared to not be an issue with this profile.Would a 1 hour on 23 hour off profile cause long term issues with stratification or scaling? Or anything else?How long does your last GP24 battery in your radio room go between charges?

2112 wrote:My WFCO boiled out my 6 1/2 year old battery (date code 06/10). She lived a good, long life but I murdered her.I've read this claim before but I'd sure like to know how a WFCO that is supposed to bulk charge @ 14.4 volts but never does can possibly "boil out" any battery that has been regularly checked for proper fluid level and not excessively discharged. :h 6 1/2 yrs service is pretty darned good for any battery so I'd have serious doubts your WFCO was in any way able to "boil out" your battery ... more likely it died of old age and because it had stratified from not being properly bulk charged. My own Interstate G27 which up until last fall had only ever seen a WFCO is now 9 yrs old and still going strong.

I'm reaching out to the WLA battery experts again.I have been charging my battery one hour a day for a few months now. It's set up to charge from 5am to 6am every morning. The thought being it would be better to give the battery a little bump during the cooler morning. When it first kicks on it draws 1.8 to 2.2A but quickly tapers down to about 0.5A and holds that for the hour.Am I seeing this correct? Should I give my battery a little taste when it's cool or during the heat of the day? Cool is a relative term. Our low is 75-80 and highs in the upper 90's.Thanks

2112 wrote:I thought I had my battery disconnect switch off for the last six weeks or so but I left it on. My WFCO boiled out my 6 1/2 year old battery (date code 06/10). She lived a good, long life but I murdered her. Is 1 hour on, 23 hours off a good profile to maintain without harming my new not yet purchased group 27 marine hybrid or can you recommend a better profile? I have been leaving it on for 2 days and off for 5 but after so many years that's getting old. I'm looking for a better way without replacing the WFCO.As one who has owned countless WFCO converters I doubt (as I said earlier) it had anything to do with "murdering" your battery. With adequate fluid there's little chance any WFCO could "boil out" any battery as rarely does a WFCO ever achieve it's advertised 14.4 volt bulk charge rate. None of mine ever have and is the reason I now instead use a stand alone CTEK charger that will. I'd say you killed it yourself by allowing parasitic draw to destroy the battery, perhaps also by not maintaining a proper fluid level in each cell. If you intend to keep using your WFCO to maintain your new battery I'd forget that timer nonsense, just plug the trailer in 24/7, and allow it to do it's job but anytime you're not plugged into shore power disconnect the battery. FWIW, my current Interstate G27 is now 10 yrs old, still maintains a full charge, and until about a year ago has seen nothing but a WFCO to maintain it. :B

Battery Storage Charge Profile | Good Sam Community

18 Replies

2112
Explorer II
Jun 25, 2017
I built this using bench parts on hand other than the board. I had to design and have it fabricated for $12.

time2roll wrote:
Seems like a rather high tech crutch. What do you do when you want to use the RV? I use it almost every day as my man cave. It's plugged in 24/7. The slides operate with it in place. I see ~1A quick reverse current spike when the slide motor energizes. This indicates to me the WFCO regulation briefly drops below the battery 12.7V

It's easily removed by loosening 2 nuts. I'll remove it when travelling.

Fully charged and disconnected, the battery is fine for 4 to 6 months. After equalization this battery measures ~12.6V in about 4 weeks of sitting disconnected. Does this comment still apply?
time2roll
Nomad
Jun 25, 2017
Seems like a rather high tech crutch. What do you do when you want to use the RV?

Fully charged and disconnected, the battery is fine for 4 to 6 months.
Could get a real Battery Tender brand charger but I would put that money toward a converter that works.
westend
Explorer
Jun 25, 2017
Gotcha!
That is a cute little tender board. Where does a guy get one of those?
2112
Explorer II
Jun 25, 2017
Thanks for your time.
I was thinking maybe it would be advantageous to charge it during the heat of the day.

I think Time2Roll could be right. It most likely shorted out and fried. It was totally dry and had a black crusty substance in each cell. I have not seen this before. Mine usually just stop holding a charge.

I'm going to see how long I can keep this one alive before needing to reset the clock with new batteries. I really don't want to move up to AGM's, replace my converter or install solar at this time. I'm happy where I am.

Here is the timer I built for it. It provides me a piece of mind. Now I can pretty much set it and forget it for some time without worrying about it.
westend
Explorer
Jun 24, 2017
2112 wrote:
I equalized and checked the water at Easter. That's the last time I used it. It's been on this timer since then.
As long as it gets a charge every day, you're golden.
2112
Explorer II
Jun 24, 2017
I equalized and checked the water at Easter. That's the last time I used it. It's been on this timer since then.
westend
Explorer
Jun 24, 2017
2112 wrote:
I failed to mention this isn't about a new battery. I'm nursing my last battery. The 4yr old OEM Continental 24 that came with the camper.
If there has been any interruption in battery maintenance, I'd suggest you do an equalization charge, fill the cells with distilled water, and follow along with your daily periodic charge schedule. At the short duration and low amps that you are doing in the charge cycle, it shouldn't matter what time or temperature you do the periodic charge.
If you're able to keep a charge voltage of under 13.6 V and are able to keep an eye on the electrolyte levels, you could keep a charge on the battery continuously. Batteries like that sort of thing. :)
2112
Explorer II
Jun 24, 2017
I failed to mention this isn't about a new battery. I'm nursing my last battery. The 4yr old OEM Continental 24 that came with the camper.
2112
Explorer II
Jun 24, 2017
time2roll wrote:
Most likely that old battery developed a short in which case 13.5 volts will boil it out quickly. That is very possible. Thanks

Although my WFCO did get stuck in boost mode a couple times subjecting the battery to 14.4 volts for over 12 hours. Could have happened to you also. Life is better without the WFCO. Mine seems to be stuck at 13.8V
time2roll
Nomad
Jun 24, 2017
Replace the WFCO with Progressive Dynamics or IOTA converter. If you do not charge with a generator then a PowerMax Boondocker is also good.

Most likely that old battery developed a short in which case 13.5 volts will boil it out quickly. Although my WFCO did get stuck in boost mode a couple times subjecting the battery to 14.4 volts for over 12 hours. Could have happened to you also. Life is better without the WFCO.

Also consider 100+ watts of solar. Works for storage, off-grid, in transit as long as the sun shines.