Battery and Solar woes

[Qwazert]

Long read, so grab a coffee...
Rockwood Mini-Lite 2306.
We’ve had this generic 100W flexible solar panel which has served us well for several years now. I hate drilling holes in the roof of my RV to pass wires through, so we simply toss the panel onto the roof when we arrive, and make connections to the controller and batteries. When not in use, the panel travels inside the RV between two mattresses, to keep it safe.
I coupled it with a 10Amp PWM controller that I had purchased from a different solar vendor a few years prior. This controller is adaptable for flooded or AGM batteries, but was set for flooded, as that is what we’ve always used. The controller has minimal user-interface (other than setting the battery type) and the only display you have is two green LED’s to indicate proper connection, and when the batteries are “fully charged” it will blink a green light to show “full”. As I mentioned, this setup has served us well for the past several years.
Last year, I needed to replace the batteries in the RV as they were over 6 years old and one of the terminals was starting to show deposits, meaning that gas was leaking through somewhere. I replaced them with a pair of Trojan T-105’s.
We do a mix of dry and full-hookup camping over the summer months, so either the solar panel or the on-board charger is keeping the batteries at the ready...according to the LED display on the controller or the one inside the RV.
Things started acting up on this last trip; after a couple of days of sunny skies, we had a few days of rain which meant the batteries wouldn’t get full power from the panel, but enough to keep the interior indicator showing 100%, and the green LED on the controller blinking. As soon as dusk fell, the indicator would show about 80% and would drop to 40% when running the water pump. This wasn’t normal, so I looked into the battery connections...definitely not perfect, but not bad enough to cause this. Cleaned them up but the results didn’t change. Luckily my buddy had a hygrometer, so I tested the individual cells...reading around 1230...only about 75% “fully charged” contrary to what my solar charge-controller was telling me.
The next few days gave us some more sun, so I monitored them carefully. According to the T-105 data sheet, the OCV of each battery when fully charged should be 6.37 yet even when I was able to achieve this reading through use of the solar panel...the hygrometer would still only indicate about 75 - 80 % charge. I use a high-end FLUKE multi-meter, in case there’s any concern about my tool-of-choice.
By contrast, my buddy also has the T-105 batteries and his OCV is around 6.9 and the hygrometer shows fully-charged.
When we arrived at the “full hookup” site the following week, the converter/charger in the RV went wild, as it struggled to charge the batteries. After about 4 hours with the fan running full blast, it finally quieted down and the batteries seemed to catch up and recuperate to full charge....or so I thought.
Checking them with the hygrometer again...only 80% charge even though the OCV was 6.6V now. By now, I’m starting to question whether this hygrometer is accurate, so my buddy takes it over to his rig and checks his batteries...100% charged.
At this point, I’m wondering if my converter/charger is defunct, so I pull out the manual and run through the troubleshooting guide. According to it, the output terminals should read 13.6 with the batteries disconnected...it only reads 13.2....half of which is 6.6...sound familiar?
I usually carry a spare car battery for Emergency use and even it shows between 1220 and 1230 on the hygrometer after being “charged” on the solar panel.
So it looks as if I have several issues at play here. One is the charger in the RV not putting out enough and the other being the charge controller from the solar panel also giving me bad intel.
I could use some advice/feedback....

[Vintage465]

EMD360 wrote:
It’s kind of fun to find this stuff out. A new 220 watt panel is now quite reasonable and that cheap controller is obviously inaccurate and could be replaced. Renogy makes a reasonably priced one and so does Grape Solar. A separate battery monitor would be a good idea too. I also changed out the WFCO for PD but I added lithium batteries. More power for fewer amp hr rating. Can be discharged 80% and the electronic monitor just turns them off if they get that low. Also turns off charging if it’s below 32° but they still release power. Insulating the battery compartment helps with this. We camped in the cold this spring and had no issues.
You will be glad you had issues because now you are more knowledgeable. I would have removed them for a deep charge too. You could even take them to an Auto Zone and they will do a deep charge and cell test for you. I was a terrible battery user for years. Now I don’t worry about it.

That's how I was...A terrible battery user. I killed so many batteries I think I actually made a noticeable differenct in Californias economy. Now I've had the same set for 4 years.....that's a record for me....heck it was a record when I hit 18 months!

[EMD360]

It’s kind of fun to find this stuff out. A new 220 watt panel is now quite reasonable and that cheap controller is obviously inaccurate and could be replaced. Renogy makes a reasonably priced one and so does Grape Solar. A separate battery monitor would be a good idea too. I also changed out the WFCO for PD but I added lithium batteries. More power for fewer amp hr rating. Can be discharged 80% and the electronic monitor just turns them off if they get that low. Also turns off charging if it’s below 32° but they still release power. Insulating the battery compartment helps with this. We camped in the cold this spring and had no issues.
You will be glad you had issues because now you are more knowledgeable. I would have removed them for a deep charge too. You could even take them to an Auto Zone and they will do a deep charge and cell test for you. I was a terrible battery user for years. Now I don’t worry about it.

[Vintage465]

Qwazert wrote:
Long read, so grab a coffee...
Rockwood Mini-Lite 2306.
We’ve had this generic 100W flexible solar panel which has served us well for several years now. I hate drilling holes in the roof of my RV to pass wires through, so we simply toss the panel onto the roof when we arrive, and make connections to the controller and batteries. When not in use, the panel travels inside the RV between two mattresses, to keep it safe.
I coupled it with a 10Amp PWM controller that I had purchased from a different solar vendor a few years prior. This controller is adaptable for flooded or AGM batteries, but was set for flooded, as that is what we’ve always used. The controller has minimal user-interface (other than setting the battery type) and the only display you have is two green LED’s to indicate proper connection, and when the batteries are “fully charged” it will blink a green light to show “full”. As I mentioned, this setup has served us well for the past several years.
Last year, I needed to replace the batteries in the RV as they were over 6 years old and one of the terminals was starting to show deposits, meaning that gas was leaking through somewhere. I replaced them with a pair of Trojan T-105’s.
We do a mix of dry and full-hookup camping over the summer months, so either the solar panel or the on-board charger is keeping the batteries at the ready...according to the LED display on the controller or the one inside the RV.
Things started acting up on this last trip; after a couple of days of sunny skies, we had a few days of rain which meant the batteries wouldn’t get full power from the panel, but enough to keep the interior indicator showing 100%, and the green LED on the controller blinking. As soon as dusk fell, the indicator would show about 80% and would drop to 40% when running the water pump. This wasn’t normal, so I looked into the battery connections...definitely not perfect, but not bad enough to cause this. Cleaned them up but the results didn’t change. Luckily my buddy had a hygrometer, so I tested the individual cells...reading around 1230...only about 75% “fully charged” contrary to what my solar charge-controller was telling me.
The next few days gave us some more sun, so I monitored them carefully. According to the T-105 data sheet, the OCV of each battery when fully charged should be 6.37 yet even when I was able to achieve this reading through use of the solar panel...the hygrometer would still only indicate about 75 - 80 % charge. I use a high-end FLUKE multi-meter, in case there’s any concern about my tool-of-choice.
By contrast, my buddy also has the T-105 batteries and his OCV is around 6.9 and the hygrometer shows fully-charged.
When we arrived at the “full hookup” site the following week, the converter/charger in the RV went wild, as it struggled to charge the batteries. After about 4 hours with the fan running full blast, it finally quieted down and the batteries seemed to catch up and recuperate to full charge....or so I thought.
Checking them with the hygrometer again...only 80% charge even though the OCV was 6.6V now. By now, I’m starting to question whether this hygrometer is accurate, so my buddy takes it over to his rig and checks his batteries...100% charged.
At this point, I’m wondering if my converter/charger is defunct, so I pull out the manual and run through the troubleshooting guide. According to it, the output terminals should read 13.6 with the batteries disconnected...it only reads 13.2....half of which is 6.6...sound familiar?
I usually carry a spare car battery for Emergency use and even it shows between 1220 and 1230 on the hygrometer after being “charged” on the solar panel.
So it looks as if I have several issues at play here. One is the charger in the RV not putting out enough and the other being the charge controller from the solar panel also giving me bad intel.
I could use some advice/feedback....

I get scolded now and then for saying this but.....seeing you as an RV owner and somewhat do-it-yourselfer, I think it's beneficial to get over "hating drilling holes in your roof". There are so many great products to make this very do-able and leak free that I consider "not wanting to drill holes in the roof" a non issue now days. I think all of us on this forum are better craftsmen than the people that built our coaches and we have the same or more products at our disposal than the builders. I've modded my solar on the roof of my RV and just took my time doing everything I wanted to and did it carefully with zero issues and we've been in some serious rain and storms too. Saying all this becuase I now have a solar system that easily keeps up with the four 6v golf cart batteries. No tilting, no setting out panels, no following the sun.......and of course no shade for my campsites!...when possible. I have this easy solar life 'cause I got over punching holes in my roof.

[StirCrazy]

Qwazert wrote:
I guess we all have a different idea as to what constitutes "camping"...to me, it has always been about minimising. The "hard-sided tent" affords us a dry place to sleep and store our gear, that's all...otherwise I would have bought a 30 ft with 2 slides and parked it at a KOA. Our next trip is for 12 days in the BC Interior with no hookups.

I do that all the time in my 40 foot 5th wheel. thats the size I ended up with to get the layout I needed so the kids and grandkids could come on trips with us. never have to worry about power even if I do use an electric coffee pot insted of the perculator. only time I get plugins is when we use it as a hotel in vancouver for the kids sports. saves 150 a night min haha.

[Qwazert]

Well a "cargo trailer" wouldn't be my cup-o-tea either. We still enjoy the finer points when connected to shore-power; A/C (or furnace as required)...blender...toaster...etc. but when boondocking or "in the wild" we manage without the luxuries, but still appreciate the Queen bed, the refrigerator and freezer. A shower tent outside for personal hygiene and a drying rack on the truck for towels and such.
Yeah...it can look pretty "trailer park" at times, but I don't go camping to impress people.

[Gdetrailer]

Qwazert wrote:
I guess we all have a different idea as to what constitutes "camping"...to me, it has always been about minimising. The "hard-sided tent" affords us a dry place to sleep and store our gear, that's all...otherwise I would have bought a 30 ft with 2 slides and parked it at a KOA. Our next trip is for 12 days in the BC Interior with no hookups.
Our trailer is a 2016, so it already has LED interior lighting. The tap-lights are just a courtesy so that you don't wake the other person, when making a trip to the loo in the middle of the night.

This morning I checked the SG on the Shumacher-charged battery; 1.277....right where it should be, and the OCV is 6.5 after letting it sit overnight.
The NOCO-charged battery still needs some lovin' as expected...she'll go on the Shumacher until her readings jive with the other...then they're back into the RV and we'll call the rescue mission a success.
Next challenge is figuring what to do....use our second existing solar panel, or buy another flexi-type...

Nothing wrong with "minimizing" but you could have bought a cargo trailer far, far cheaper, tossed a couple of cots in it and called it good which is as minimal as you can get without a tent. On top of that would not needed solar and batteries. That is essentially what you are using the more expensive RV as.

If your RV has electric available while at home, plug it into shore power and the converter would have done the charging work for you. Even the WFCO converter you have would have eventually recharged both batteries and eventually they would equalize together. The key with WFCO is you need to remove every parasitic draw. Those draws are enough to prevent the WFCO from switching modes. A simple bit of rewiring to allow a switch to disconnect the loads via your fuse panel.

Getting a battery from 90% to 100% charged takes considerable amount of time at very low charging rates and that can be shortened if you have a larger charger which is capable of sustaining a higher output voltage and amperage. Those little portable things cannot sustain a high enough voltage and amperage compared to the battery size. Those chargers are designed for small car and lawnmower batteries (40Ahr or less).

The larger capacity of the battery, higher the charging current will be needed.

While a 100W (5A worth of charge) panel may have marginally worked for say a group 24 or Group 27 battery (60Ahr and 70Ahr respectively) it isn't enough for a 215Ahr battery as your T105s.

One of the main keys to keeping your battery happy and healthy is to put back as much of the energy used as fast as possible. Each time you draw the battery down some, that needs to be put back in as soon as possible.

[ewarnerusa]

For reference, we have 280 watts of solar mounted fixed and flat on the roof routed to a Morningstar PWM controller charging 2x6V GC batteries in series. We only boondock and power is usually never an issue for our long weekend warrior style of camping. I'd say we are moderate power users, we run an inverter and use some gadgets but no high draw items. Occasionally a 300 watt electric rice cooker.

[Grit_dog]

Your converter s ucks. I didn’t believe they were that bad until we got (the same model as yours) in our newer camper. Notice you’ll never see actual 14+V charging out of it. WafCO converters are just not good unfortunately.
Get a new quality converter or add a good charger (for less $ than replacing the converter) and then think about upping your solar game if your charging doesn’t keep up with use.
JMO. Happy camping!

[2oldman]

Qwazert wrote:
I guess we all have a different idea as to what constitutes "camping"...to me, it has always been about minimising.

Fine for you, but I can't imagine not taking a hot shower every day, having internet, watching TV in the evening and coffee and toast in the morning... on batteries.

[Qwazert]

I guess we all have a different idea as to what constitutes "camping"...to me, it has always been about minimising. The "hard-sided tent" affords us a dry place to sleep and store our gear, that's all...otherwise I would have bought a 30 ft with 2 slides and parked it at a KOA. Our next trip is for 12 days in the BC Interior with no hookups.
Our trailer is a 2016, so it already has LED interior lighting. The tap-lights are just a courtesy so that you don't wake the other person, when making a trip to the loo in the middle of the night.

This morning I checked the SG on the Shumacher-charged battery; 1.277....right where it should be, and the OCV is 6.5 after letting it sit overnight.
The NOCO-charged battery still needs some lovin' as expected...she'll go on the Shumacher until her readings jive with the other...then they're back into the RV and we'll call the rescue mission a success.
Next challenge is figuring what to do....use our second existing solar panel, or buy another flexi-type...

[Gdetrailer]

Qwazert wrote:
You've obviously hit the nail on the head.
My problem is that I didn't think that adding "better" batteries would create a problem....if I knew then, what I know now....

Looks like some more panels are in my future.

It isn't the fact of adding "better" batteries, it is about adding more battery capacity in Ahrs which then leads to you to using more of that capacity well past what you were before without really knowing you are.

Without doing an exact energy audit to fully understand how much you are using vs how much you are able to harvest you are just taking a blindfolded shot at a distant target.

Personally, adding an additional 200W of solar will result in you not needing to resort to using a bunch of battery powered flashlights using expensive drycells.. Dump the drycell flashlights, replace the incandescent bulbs that may be in your RVs light fixtures with LEDs.. You get much better lighting and the side result of dropping the cost of drycells you waste money on (doesn't take long to spend $50 on drycells now days). Most flashlights use inferior quality LEDs which have far less lumens per watt and pretty poor color rendition.

Additionally adding more solar may even allow you to take luxurious baths (even if it is a 5 minute "Navy bath") inside your RV assuming you have a tub or shower..

As it is right now, basically your using your RV like a hardsided tent.. Not my cup-o-tea. When I camp, I like to make use of the nice facilities that are built into the rig..

[StirCrazy]

Qwazert wrote:
You've obviously hit the nail on the head.
My problem is that I didn't think that adding "better" batteries would create a problem....if I knew then, what I know now....

Looks like some more panels are in my future.

to give you an examble I am running a 24v 325watt split cell panel on my camper with a MPPT controler that supported two 6V batteries like you have, and it works great (this year I upgraded to LFP batteries though).

On my 5th wheel I am running three 160 watt 12V panels on a PWM controler servising four 6V batteries. while th 5th wheel works great and I never have to worry about plugging in, unless I want to run the bar fridge, the margaretaville and the ice machine :B the 480 watts of solare on it doesnt give me as many charging amps as the 325 watt panel on the mppt controler, and thats just a factor of the efficiency of the panel and the way a mppt controler works.

In the camper in vancouver at the end of june, I was getting 1.2amps of charging at 6:20am and by 8am I had 8 amps. on a good day I see 22-24 amps for the peak hours.

one of the biggest things is to get a programable controler so you can set it up to match your batteries, every manufacture has slightly different peramiters they want. and I always say get the biggest panel you can reasonable aford. my 325 watt on the camper cost me 200 bucks which is very reasonable. the 5th wheel is getting the 160's upgraded to three 350watt or larger. I also say to find a 24V split cell design as they are way more efficient in low light so where we live it benifits us a lot. and last your controler. when I buy a trailer/5th or what ever, before it leaves the lot the WFCO is taken out and replaced by a progressive dynamics charger. to many issues with WFCO as other have said, I have had three of them fail on me in 5 units I have owned. the last two didnt fail because they were taken out and replaced before I took the units haha.

oh and don't worry about having solar and show power at the same time, I alway do when im at home.

any questions feel free to ask or PM me if you don't want to ask in public I am sure any of us would be happy to help.

Steve

[wa8yxm]

PWM controllers work by turning on and off. MPPT controllers work by kicking voltage up and down as needed (Buck/Boost) from what I understand... Maximum Power Point Transfer is what MPPT means. This results in a faster re-charge"

A pair of T-105's is around 230 amp hours a 100 watt panel is good for perhaps 80 amp hours a day TOPS.

[Qwazert]

You've obviously hit the nail on the head.
My problem is that I didn't think that adding "better" batteries would create a problem....if I knew then, what I know now....

Looks like some more panels are in my future.