Solar Not Charging Lithium Battery

[scorz77]

Hello all! I recently switched over to LiTime 140AH lithium battery as well as their lithium-compatible solar control charger. In doing so, I had it wired at the dealership. The solar panels are not charging the battery at all, and the solar control charger isn’t even sensing that there are solar panels on the roof. The dealership is saying that the control charger is faulty and that I need to replace that. When I reached out to LiTime’s customer service, they are saying that the solar panels need to be replaced. Conflicting stories are making me not trust either source. Has anyone had a similar issue when switching over to lithium where the solar panels are no longer charging the battery?

Given, my trailer came with 150 total watts of solar being able to charge the original group 24 deep cycle battery (one 100-watt panel + one 50-watt panel). Now that my lithium battery is 140AH, I know that I need to upgrade my solar to at least 300 W to effectively charge it. But I pulled the fuse out of my 12 V refrigerator so that way the 150 W solar panel would charge the battery when not being used. I’m driving my trailer to storage as we speak and will be leaving it there until Memorial Day weekend when I’ll be using my trailer again. My fear is that I will go to pick this trailer up in two weeks and the battery will be completely dead.

My trailer is a 2022 Gray Wolf 26DBH travel trailer. Any and all help would be greatly appreciated!

 

[bikendan]

Pics of how the dealer wired the batteries might help.
Pics are often more helpful than descriptions.

 

[scorz77]

These are the only photos of I have of the setup. I attached a picture of the wiring on the roof for the solar panels. The solar panels are the originals that came with the trailer when I bought it from the dealership in 2022. Only the battery and solar control charger are new.

Pics of how the dealer wired the batteries might help.
Pics are often more helpful than descriptions.

 

[scorz77]

These are the only photos of I have of the setup. I attached a picture of the wiring on the roof for the solar panels. The solar panels are the originals that came with the trailer when I bought it from the dealership in 2022. Only the battery and solar control charger are new.

 

[Aussieguy]

13.6 is good for a battery
Use the buttons to scroll through screens to try and find the solar power being produced panel

With a full battery you should see voltage at the panels but very few amps if any going to battery

You should see around 20 v for yhe panels

If you got multimeter use it to confirm panels are producing volts

To check amps turn on as many 12v devices you can at once and watch the screen
It should start showing some amps being used


That controller is huge 60amps
You could put 800w of panels onto it
Work out what is the biggest panels you can fit on the roof….. but do NOT MIX panel sizes unless you consult a knowledgeable person

Look at a minimum of 2 x 200w panels
4 would better

Mixing panels you can easily lose a lot of panel production

Also look at residential panels they use higher output volts
I got 2x 370w panels and they work great at powering all my 12v including fridge and furnace working at same time

 

[Boomerweps]

Seperate issue from no charging at all:
Two different sized panels do not always play nice together.
Are they in series or parallel? They look like a parallel adapter was used.
In series the voltages add up, but the lower amperage is the most the stronger panel will put out, I.e., lost watts.
In parallel, the lowest voltage will be used by both panels, the amps will just add together, again, lost watts.
Watts are volts times amps.
You need to find the voltage and amp rating of each panel to determine the best way to connect them.
Replace the 50 watt panel with a matching 100 watt or better still replace them both with a 200 watt panel and be happy

 

[scorz77]

13.6 is good for a battery
Use the buttons to scroll through screens to try and find the solar power being produced panel

With a full battery you should see voltage at the panels but very few amps if any going to battery

You should see around 20 v for yhe panels

If you got multimeter use it to confirm panels are producing volts

To check amps turn on as many 12v devices you can at once and watch the screen
It should start showing some amps being used


That controller is huge 60amps
You could put 800w of panels onto it
Work out what is the biggest panels you can fit on the roof….. but do NOT MIX panel sizes unless you consult a knowledgeable person

Look at a minimum of 2 x 200w panels
4 would better

Mixing panels you can easily lose a lot of panel production

Also look at residential panels they use higher output volts
I got 2x 370w panels and they work great at powering all my 12v including fridge and furnace working at same time

I already left the trailer in storage so I’ll have to go back and check out what the controller screen shows as I scroll through it. Hopefully, the battery isn’t completely dead tomorrow afternoon when I’m able to go check it out.

I’ll surely take some roof measurements and fit as many panels as I can going forward. I’d surely like to get at least 300 W worth of panels, but I’ll go more if I can fit the panels. I’d love to be able to boondock for a long weekend without having to run my generator for 8+ hours a day.

 

[scorz77]

Seperate issue from no charging at all:
Two different sized panels do not always play nice together.
Are they in series or parallel? They look like a parallel adapter was used.
In series the voltages add up, but the lower amperage is the most the stronger panel will put out, I.e., lost watts.
In parallel, the lowest voltage will be used by both panels, the amps will just add together, again, lost watts.
Watts are volts times amps.
You need to find the voltage and amp rating of each panel to determine the best way to connect them.
Replace the 50 watt panel with a matching 100 watt or better still replace them both with a 200 watt panel and be happy

I already left the trailer in storage so I’ll have to go back and check out what the controller screen shows as I scroll through it. Hopefully, the battery isn’t completely dead tomorrow afternoon when I’m able to go check it out.

I’ll surely take some roof measurements and fit as many panels as I can going forward. I’d surely like to get at least 300 W worth of panels, but I’ll go more if I can fit the panels. I’d love to be able to boondock for a long weekend without having to run my generator for 8+ hours a day.

I never even thought about this. I guess that’s because this is how came right from the dealership when I bought it. I’ll be replacing them, for sure, with at least 300 W of solar, but definitely more if I can fit them on the roof.

 

[larry2c]

It's hard to tell but in the picture of your charge controller it looks like there is only one lead coming in from your panels to the "solar in" connection points... (far left of the controller no + line in?)

 

[scorz77]

It's hard to tell but in the picture of your charge controller it looks like there is only one lead coming in from your panels to the "solar in" connection points... (far left of the controller no + line in?)

Sorry for the poor photos. That’s the thing, there are lines going into the far left port. There’s 6 ports, all 6 ports have lines going into them. The current panels charged the previous lead acid deep cycle battery I had with the old Waaree solar controller. But they don’t seem to even register a connection to the new solar controller or new lithium battery. My assumption it either wasn’t wired correctly at dealer when they installed the new controller for me, or the panels (150 W total) aren’t producing nearly enough to charge the 140AH lithium battery.

 

[Aussieguy]

150w of panels is not a lot and they are laying flat. You probably only getting 80 to 90w out of the panel

That controller can handle about 800w
Of panels
Look at your roof and get as much solar as you can up there

The picture showing 13.1 and the battery symbol indicates it found your battery

Use the buttons to scroll the screen to the panels section that shows watts being produced

 

[Aussieguy]

PS

The 2 wires to the lightbulb symbol is a load…. Where do those wires go?
What is getting powered as it shares the panel output…. There may be no power left for charging the battery as well

 

[mnoland30]

If you don't have a multimeter, get one. They are $7 at Harbor Freight. Pull the two wires from the panels and see if you're getting voltage. That will tell you if your panels are working.

Next, replace the solar panel wires (make sure polarity is correct), then pull the two wires going to the battery. Check the voltage at the controller where you just removed the two wires. You should be getting around 13.4v for a charged battery, and 14.25 for a depleted one.

If the panels are working, and you're not getting voltage out, then it is your controller.

If both panels and controller are working, check the wiring to your battery.

I assume you have a 12v fridge. If it were me, I'd put a switch near the controller to turn off all of the loads coming out. You might want to try disconnecting the load wires and see if that changes anything.

Let us know how it goes.

 

[scorz77]

Here are the photos of all the screens as I scrolled through. The battery was at 13.2 volts, and not plugged into shore power or hooked up. What strange is that it was in storage for the last two weeks, not hooked up to any power at all. When I checked the battery life via the app and Bluetooth connection, it was reading 99%. Given, I unplugged the 15 amp fuse that powers the refrigerator, but I’m still surprised to see that the battery stayed at 99% over two weeks. I thought that the solar was actually working, but the controller isn’t registering them. Because when you look in the photos, the solar panel wattage reads 0.0.

 

[scorz77]

It's hard to tell but in the picture of your charge controller it looks like there is only one lead coming in from your panels to the "solar in" connection points... (far left of the controller no + line in?)

Here are better photos of the lines going in. They seem to be fully connected.

 

[tomkatb]

On their best day. Not often in the Midwest. A 100 watt panel on the roof can produce 25 amps. Your daily usage with a compressor fridge is likely 100 amps or so.

So do not expect much. But, on a sunny day your meter should be well above. 14 volts.

Use your meter on that controller. First two is the solar panels. Second two are the battery. Should only read after the sun goes down. Or you are reading the charge current. Not the battery.

So far not any usable data. No idea what the meter is measuring. Nor time of day. Recording readings every three hours on the two sets of terminals with a meter will answer most questions. Also after dark.

 

[Aussieguy]

I am not seeing any indications of the panels on the controller.
Look at the manual it show screens different than yours

Found the manual here…

https://cdn.shopify.com/s/files/1/0667/7220/5788/files/LiTime-48V60A_MPPT_-US_EN.pdf?v=1744188926

You might try downloading the Bluetooth app it might be easier to use

Disconnect the panel wires and use a multimeter to check voltage
It should be around 20 v … if not you need to get on roof to test panel connections


If you don’t have a meter … get one
Cause trouble shooting is almost impossible without one

 

[scorz77]

On their best day. Not often in the Midwest. A 100 watt panel on the roof can produce 25 amps. Your daily usage with a compressor fridge is likely 100 amps or so.

So do not expect much. But, on a sunny day your meter should be well above. 14 volts.

Use your meter on that controller. First two is the solar panels. Second two are the battery. Should only read after the sun goes down. Or you are reading the charge current. Not the battery.

So far not any usable data. No idea what the meter is measuring. Nor time of day. Recording readings every three hours on the two sets of terminals with a meter will answer most questions. Also after dark.

Before I left for work this morning, I cycled through the screens again. Lo and behold, the symbol for the solar panels is actually showing up on the screen. That is the first time I’ve seen that. I have my trailer plugged in at home now on a standard exterior outlet from my home, using an extension cord and a 15A-to-30A adapter to plug into the trailer. Nonetheless, I’m not 100% sure why the symbol for the solar panels is now showing up. I did not check with a multimeter. I’ll do that today when I get home from work, before taking off for our MDW trip.

 

[Aussieguy]

If it is night time…. Panels are not producing any power and possibly the controller can’t detect the panels

for power going to battery
If the “LOAD” wires is powering something there may not be any power available to charge battery

Find out what is connected to the “load”

You only got one panel …. It may be only producing a very small amount of power
Disconnect the load and then see if anything power going to battery

 

[tomkatb]

Create a sheet with three columns.

Time, voltage battery, voltage solar.

Record with a voltmeter on contacts at the controller. At 1200, 1500, 1800, 2100, 2400 hours. Take a picture of the screen.

Answer will be obvious.