Batteries/solar not holding up, troubleshooting help please

[twvette]

I have no luck getting batteries to hold up it seems. Had a couple different RV's and different setups too (wet cell, lifeline golf cart, gel deep cycle batteries)and none have ever held up well.

Anyways, here is what I have now:
- Onan 5500 gen
- Iota DLS-45 converter
- Three Optima Bluetop D31M (less than a year old)
- Large solar panel (or maybe it is even two combined together?)
- Shell Solar RV 20 solar controller /monitor
- Only camp in AZ so almost always get great solar

Worked great in beginning but seem to be on downward spiral. I now can't get through even a mildly cold night (mid 40's) of heater use only without them dying. I have had to run the generator much more even with the solar system to get/keep them fairly charged whereas before the solar panel would generally give me full recovery from typical day and night use.

Here are some observations:
- I previously got 13.4 volts or higher when running the generator but now only see 13.0, and settles at about 12.7v a little while after shutting off generator
- When shutting off generator I never get much more than an "OK" status on my monitor whereas as before I would typically be at "GOOD" or a few LEDs above at least for a while
- Connected an automotive style battery charger after charging with generator for a while and it also claimed the batteries were fully charged.

Here are some questions/concerns:
- Is the solar system overcharging my batteries slowly killing them?
- I do not have the Iota IQ4 smart charge option as far as I can tell, perhaps this will help? Seems like a long shot as had this in previous RV and did not see any real improvement but maybe would prevent Onan 5500 from improperly charging gel batteries this time around?
- Generator/Iota DLS-45 issue in general? All my RV's have had this same setup
- Is the Shell Solar RV 20 junk or good? I did not purchase or install this system.
- Can anyone tell from pics below which solar panels I might have? I have no clue on make/model/output and no markings on them even underneath!
- Maybe I am leaking back power through the solar panels at night?
- Would putting an ammeter inline help figure this out? Maybe a Doc Wattson http://www.rc-electronics-usa.com/ammeters/rv-battery-monitor.html
- How to test my batteries to see if they are still good? Maybe only one battery is bad?







Thanks for any help!

[Harvey51]

Or use less electricity. It will be useful to watch how much is used by the various devices using the ammeter or amp-hours on a battery monitor. We often go 3 days without any charging in summer on 2 batteries.

[Golden_HVAC]

Hi,

I agree with the posts above, the panels are TINY! I had a pair of 45 watt panels, probably larger than those, and gave them away, they just don't produce much power. They now charge a small electric wheelchair battery (retired from the wheelchair, so condition not to great of one) and run a dozen or so 24 LED 5050 panels, each use about 0.15 amps. So perhaps 2 amps total load to light up my buddy's house. It worked great in the summer, when there was 14 hours daylight, and only 6 hours to run the lights. In the winter, it does not work so well. ..

My 120 watt solar panels will put out about 35 AH daily each. My RV uses about 35 AH just to run the propane leak detector, CO detector, and refrigerator each day.

What I found is if I have removed a total of about 120 amp hours from my 4 golf cart batteries every night, the 70 amp charger/inverter can put out 45 amps for the first 30 minutes, and will taper to less than 30 amps within 1 hour. At that point, I will shut off the generator, and expect to receive about 90 AH all day, sometimes I don't get that many amp hours, but most of the time I do.

If I end a long week of camping and still am -100 AH, then that is not a problem, because I stop camping, and the solar will fully charge it the next few days. I try to avoid running the generator mainly to save fuel, but also because I love the quiet solar system, and hate the Onan generator noise.

I have a E-meter and a shunt that carefully measures the amp hours going into and out the battery bank. This is similar to a "Trimetric" meter.

So my suggestion is to add a couple more solar panels. SunElec.com sells them for close to $1 per rated watt. 100 - 150 watts is my suggested size. Larger than 150 watts, and finding real estate on your roof becomes really difficult.

You should also consider your options on the 120 volt charger. It seems like it is coming out of 'absorption charge' to quickly, and switching to a 13.2 volt holding charge rate to soon. What brand converter / charger do you have? What is it's amp rating?

When running your Onan, what output voltage are you getting? 110 or closer to 120 volts? Some chargers do not work well with a generator that only puts out 110 volts.

Good luck!

Fred.

[MEXICOWANDERER]

KILL IT! IT'S MULTIPLYING!

[MEXICOWANDERER]

This is where an AMP HOUR METER makes it's bow. It will display simple checking account balance numbers that verify

OVER DISCHARGING

INADEQUATE RECHARGING

in such a simple and easy to understand format that it does not need a Gyro Gearloose nerd to interpret the numbers. Use and misuse needs to be displyed to and understood by the user.

"Gee the batteries are not recharging enough" or "oh my god, I am draining them dry" is a hell of a lor better than "Huh? What the hell?"

Amp hour meter install FIRST without question.

[full_mosey]

Hi twvette;

I have been using AGMs since 2009 and I have two Optima D34M that will start their 6th year this coming Jan.

Your Battery specs are on pp 5-6, mine are on pp 7-8. You have a 225AH battery bank. That ought to be plenty for a day's use.

I agree with pianotuna about the lack of adequate charging. Your batteries are in danger of being permanently damaged by sulphation.

The 12.7V you say represents a 75% charged AGM. Don't be fooled by Voltage charts for flooded batteries! A fully charged Optima like ours will read 13.1V 24 hours after a full charge. Mine are older and only read 13.04 the last time I tested them. That means disconnected and after 24 hours resting.

Let's get those babies charged. 🙂

HTH;
John

[pianotuna]

Hi,

3 amps corresponds to about 36 watts. 5 is more like 60 watts.

Under charging still applies as you don't have enough solar wattage to fill the batteries. AGM do require higher voltages--but as I said before check with the maker.

Fully charging is going to take far more than 3 hours. Only two ways make sense to do so. Shore power, or enough solar.

[twvette]

Thanks everyone. Here are some answers/input:

- Already have IQ4 purchased so will get it installed for next trip
- Good excuse if nothing else to add more solar so I will start looking into that.
- Use the RV once to twice a month for weekends primarily and sits in storage with solar charging active (no shore power charges) and all other 12V turned off with the main 12V switch
- Only ran them dead once maybe twice but very low many times now
- I typically get a little over 3 amps of solar charge and have seen up to 5 amps briefly. Does this correlate to what wattage panel I likely have? Again, I cant find any markings on it and bought RV used so clueless.
- I have seen voltage a bit above 13V previously but never above 12.7 after a long generator charge.
- I was getting spoiled with the solar so have been leaving the inverter on to power portable satellite and TV with a good amount of TV use so it makes sense not getting a good deep charge during the day
- I store/use in high elevation for summer use and desert in winter so temps are usually 40-50's for lows and 60's to 80's for highs

Does the undercharging theory still hold even when it sits weeks in storage with no use with the 3 amps or so providing charging or does it just need a long high amp charge?

One of my main concerns is that I use to get 13.4V with generator running now only 13V. What explains this or is there an adjustment on generator/converter I need to do?

[pianotuna]

Hi,

What the results indicate is chronic under charging of the battery bank.

How often have you depleted them to "dead"?

How many watts of solar are there?

What is the ambient temperature this time of year?

Optima batteries are not often used for deep cycle storage. Why? Because of the spiral design there is a lot of "empty space" that a more tradition grid and paste design fills with lead. That means the Optima per unit of volume used (not the actual cells but the foot print) is considerably lower.

At this point, what may be needed is reconditioning or equalization of the batteries. That is much more difficult with the AGM format, so I'd be writing to Optima to ask for their specific advice. I'd also do one battery at a time.

If you don't wish to take the "risk" of equalization, at least find out what Optima recommends for a maximum charge voltage and tweek the existing equipment to provide that during charging.

Another strategy would be to spend 168 hours on shore power to see if that will return the lost capacity. Do the research necessary to find out the best voltage for doing that.

With such a small amp-hour capacity battery bank, I'd recommend leaning towards 150 watts per 100 amp-hours of capacity. I think the Blue tops are about 85 amp-hours each, so the solar system needs to be approximately 400 watts. The bare minimum would be approximately 160 watts.

[time2roll]

Are you full time? Or what happens in storage?
You definitely need the IQ controller.
Need to display the array current on controller to get charging amp readings.
What is the highest voltage you have seen from solar?
Looks like maybe 30 to 50 watts solar and that is not much for camping although probably adequate for storage.

[BFL13]

You do need the IQ4.

AFAIK Optimas are AGM, not "gel"

You seem to be suffering from undercharging by not getting the batts high enough in SOC with the gen running to then leave the rest to the solar at this time of year. The IQ4 will let you get higher in SOC for the same generator running time as without it.

That causes "progressive capacity loss" where each incomplete "cycle" leads ever downward in capacity. You need a truly full charge followed by an "overcharge" (called a "conditioning charge" with AGMs) to restore your batts to good health.

Your solar is likely ok, but you need more (" quality" gen time this time of year--IQ4- before letting the solar do the rest before it gets dark.

[groundhogy]

Here are some questions/concerns:
- Is the solar system overcharging my batteries slowly killing them?
This one seems possible to me. Your generator should be booming
those batteries compared to the panels. If the gen cant get the
batteries up to full charge, I suspect the batteries are getting
damaged or need distilled water.
On my boat, I got hit with lightning and it took out the diodes in my alternator (how I charged them with motor). Not sure how onan generators work. My batteries boiled and died.


- Maybe I am leaking back power through the solar panels at night?
Any good solar charge controller should not let this happen.
They should only let charge flow to the batteries from the panel.


- Would putting an ammeter inline help figure this out? Maybe a Doc Wattson http://www.rc-electronics-usa.com/ammeters/rv-battery-monitor.html
I think this device, if I remember correctly is for tiny currents?
Your panels will be lots from the looks of them. Like 5-10 amps maybe.

The solar panel manufacturer and partno. should be on the back of the
panel I think. You can look up partno. on internet.
But, I think they should be like 15 to 25 volts dc if you disconnect
their wires and put a voltmeter on them (panel in sun).

- How to test my batteries to see if they are still good? Maybe only one battery is bad? Need to test under BIG load. Take to store?

and.... I never heard of using batteries to make heat....
making heat takes lots and lots of energy. Energy that batteries
don't have. Maybe that's how the batteries are dying.

Most people use fossil fuels to make heat.
Theres a reason that no one can replace gasoline or diesel or propane.
A teaspoon of that stuff has a lot more energy than anything else. Its not even close.

So most people use a propane heater, electric heater (hooked up to
power company), or diesel/kerosene, or even a coal stove. lol.

gh