LiFePo4 battery upgrade. What effect will it have regarding TV charging?

CapnArt

I'm upgrading to a Lithium battery, and I've been unable to determine whether I need to make changes to the TV-Trailer wiring. Possibly a DC-DC charging module?? I'm hoping some one can provide T@g specific experience, or a definitive answer. Thanks.

JamesDow

No special changes needed. For my 2018 I needed to swap wires for battery to SAE solar plug. When just plugged into shore power, my converter charged lithium battery to around 84%. If plugged in with a draw (Norcold refigerator) it will charge up to near 100%. The difference is getting the converter to automatically switch to other charging modes. As for DC-DC charging module. I found no need with my 2012 Toyota RAV4. I gain about 11% battery state of charge per 200 highway driving miles. I did put an inline switch between my TV and trailer to be able to easily disconnect between the batteries. This is occasionally used when I am connected for an extended period with the TV not running. Could also just disconnect the 7 pin TV/trailer connector wire.

My 100 watt solar suitcase can get things daily to 100% with good sun.

Bottom line, do the battery change and use it for a bit. Even though I have a home battery charger with a lithium switch I never have a need to use it.

Changing over to a lithium battery was by far my best mod.

Search this site for a lot more information.

Best of luck.

GulfCoast

I second what @JamesDow said. I didn't bother to run a charging circuit from the TV and we've found that we don't miss having it. With a load, the stock converter in our 2017 T@G takes the LiFePo4 battery to 100%. And the solar panels have been able to keep up with our needs when we're not connected to AC power.

MrGneissGuy

I third it as well. I added a LiFePo battery on our 2015 T@G last year without changing anything else. Without load, I can only charge to the upper 80% range on shore power. With a good sunny day the solar panels can top it off pretty quickly.

I got a Renogy with a Bluetooth module and was able to confirm by the app that the TV provided charge while driving.

normaandchris

While I can’t “fourth” this, I certainly appreciate the question and answers. We need to change our lead acid battery in our T@G and have been going back and forth with what to do. Most use is on shore power, but we have been forced to do 12V battery only and our small refrigerator (Massimo) doesn’t work for too long on the battery alone.
These three comments make me more comfortable with getting a LiFePO4 battery and maybe not charging while driving (2019 GMC Canyon), letting the battery power the refrigerator, and then going back to shore power (or our small solar setup if not available) to bring it back to 14V or so.
Searching this and other sites certainly opens up a cavernous rabbit hole on this subject, that’s for sure.
Chris

SueBHunny

I did exactly what @MrGneissGuy did. The LiFePo battery with the solar suitcase meets all of my needs. And I'm almost never plugged in.

JamesDow

Below is a Youtube video testing a BougeRV 30quart fridge with a 100 amp hour Chins lithium battery.

Results = 102 hours.

This matches my experience (I get a little better), but I usually never drop below 20% state of charge.

https://youtu.be/jc9qnPqmsHo

GulfCoast

Refrigerator power consumption is strongly related to the thermostat setpoint and ambient temperature. There's usually not much to be done about the outdoor temperature, other than avoiding sun on the galley. But using the highest thermostat setpoint tolerable will make a lot of difference.