Solar in RV with lithium battery question

[airborne spoon]

I am installing a 200w solar panel on my trailer and I'm getting a 40A MPPT charge controller that will charge a 200Ah lithium battery.
I know i need to have a lithium specific charge controller coming off the solar panel. But what about for the power that comes from the main inverter when I'm plugged into shore power? Its made to charge a lead acid battery so does that mean a need another charge controller to go from that 12v line to the battery?

 

[dhrivnak]

If you go with a “drop in” replacement like BattleBorn or Renogy you should be fine. I use a Renogy lithium in my ALiner. 100% more storage At 1/3 the weight. I just adjusted the voltages on the Windy Nation charge controller I use.

 

[airborne spoon]

If you go with a “drop in” replacement like BattleBorn or Renogy you should be fine. I use a Renogy lithium in my ALiner. 100% more storage At 1/3 the weight. I just adjusted the voltages on the Windy Nation charge controller I use.

They call them drop in replacements but they aren't because they charge to different voltages than a lead acid battery and if you just drop it in and carryon like normal it shortens the life of the battery considerably.

You have a different controller than the one I'm looking at (BougeRV 40A MPPT). And adjusting the voltage is the correct thing to do but that still doesn't change power coming into the battery from the shore power side. That line is the same as the out line from the battery, my battery has 2 wires and that's it there is no secondary line for charging the output is the same as the input.
When i get the solar hooked up there will be an additional line input from the solar controller but the main line going to the breaker box is still there and that's how it charges off shore power, so logically it would seem i need to cut that line or add a second inverter.

 

[glide]

I am installing a 200w solar panel on my trailer and I'm getting a 40A MPPT charge controller that will charge a 200Ah lithium battery.
I know i need to have a lithium specific charge controller coming off the solar panel. But what about for the power that comes from the main inverter when I'm plugged into shore power? Its made to charge a lead acid battery so does that mean a need another charge controller to go from that 12v line to the battery?

You absolutely need a new charge controller to charge the Lithium batteries from shore power.

BattleBorns and the like are NOT simply drop-in replacements as advertised.

Your existing controller may already have a setting to charge lithium depending on your year and model.

 

[dhrivnak]

They call them drop in replacements but they aren't because they charge to different voltages than a lead acid battery and if you just drop it in and carryon like normal it shortens the life of the battery considerably.

You have a different controller than the one I'm looking at (BougeRV 40A MPPT). And adjusting the voltage is the correct thing to do but that still doesn't change power coming into the battery from the shore power side. That line is the same as the out line from the battery, my battery has 2 wires and that's it there is no secondary line for charging the output is the same as the input.
When i get the solar hooked up there will be an additional line input from the solar controller but the main line going to the breaker box is still there and that's how it charges off shore power, so logically it would seem i need to cut that line or add a second inverter.

Actually just the opposite in my experience. Lithium can charge to a higher voltage so using the default lead acid charger you get about 80% capacity which is still 60% more capacity than a lead acid. When boondocking on solar we go to 100%. Four years in and looking good. Has lasted longer than the initial lead acid.

 

[airborne spoon]

You absolutely need a new charge controller to charge the Lithium batteries from shore power.
BattleBorns and the like are NOT simply drop-in replacements as advertised.
Your existing controller may already have a setting to charge lithium depending on your year and model.

i read the manual and also took it apart and looked around there isn't anything anywhere about the mention of lithium so i think its not made to support it, its a WF-8735

Actually just the opposite in my experience. Lithium can charge to a higher voltage so using the default lead acid charger you get about 80% capacity which is still 60% more capacity than a lead acid. When boondocking on solar we go to 100%. Four years in and looking good. Has lasted longer than the initial lead acid.

I made a 7 pin trailer connection for the tesla but i don't connect the 12v line off the car to charge while traveling, (I don't want the parasitic drag on the 12v tesla battery) I'm going to be using the solar and shore power to keep my battery charged up. And I'll also be using shore power to charge the tesla so i cant be waiting all day for the battery to charge before i can plug in my car.

While traveling the fridge will be drawing 12v power from the battery and its not a bunch but if its hot and i open the cooler a few times to make lunch at a supercharger or something it could draw up to 30-60Ah in a day depending on what setting the fridge is on according to the manufacturer

 

[dhrivnak]

i read the manual and also took it apart and looked around there isn't anything anywhere about the mention of lithium so i think its not made to support it, its a WF-8735

I made a 7 pin trailer connection for the tesla but i don't connect the 12v line off the car to charge while traveling, (I don't want the parasitic drag on the 12v tesla battery) I'm going to be using the solar and shore power to keep my battery charged up. And I'll also be using shore power to charge the tesla so i cant be waiting all day for the battery to charge before i can plug in my car.

While traveling the fridge will be drawing 12v power from the battery and its not a bunch but if its hot and i open the cooler a few times to make lunch at a supercharger or something it could draw up to 30-60Ah in a day depending on what setting the fridge is on according to the manufacturer

I connected the 12v in our Volt, Model 3 and RAV4 Prime. Over 45,000 miles towing and have never had an issue save the one time I forgot to switch the fridge to propane and depleted the battery in both the trailer and the Volt. But borrowed an extension cord and the trailer converter kicked on and charged both the Volt and the trailer.