380 Watt Solar Panels and Lithium Upgrade on T@B 360

Trailpixie

I am preparing for my first spring outing with my Black Canyon T@B 360. The  solar system remains a bit of a mystery to me. Sitting in my driveway here in Maryland the solar panels aren't keeping the system topped up to 100%. The only way to stay charged is the shore power. My previous T@320 with 200 watts solar and 300ah of AGM batteries was easily kept charged in winter without shore power. I had that for five years. My new camper is sitting on the north side of my house so it doesn't have direct sun, but it does have full exposure to the sky. This should bring in more than the 15-88 watts that the system says it is providing.

The dealer has told me that because the lithium system needs to run the battery heater, the solar panels can't keep it charged. To me, this means that the lithium upgrade makes the T@B 360 less effective as a camper for the cooler shoulder season because the solar system can't keep up with the battery heater.

What am I missing? Is there something wrong. I do have experience with solar panels and with T@Bs, so I don't think I am crazy, BUT I haven't worked with lithium. 

RTWCTS

@Trailpixie, unless you are experiencing extreme cold you shouldn't need to run the battery heaters to charge your batteries. Just how cold is it in Maryland? My 400 has a switch to turn the heaters on and off. Assuming the battery switch is off too, I wouldn't think you'd even need to recharge sitting there dormant. 

Edit to add: You'd only need to use the heaters when trying to charge below freezing. The internal electronics should shut down an keep the battery from charging if the temp is too low. At that point you'd turn on the heaters.

Trailpixie

what state should I leave it in when it is parked?

pthomas745

The battery heaters in the newer trailers with the Battleborns use 1.8 amps per battery when they are running. Your solar panel should easily replace that amount of power.  (Well...maybe not overnight...so check to see if your heaters are running!)

The point of a battery heater gets sort of lost in the shuffle when lithium batteries and cold weather get mentioned.  If a lithium battery....the cells...inside the battery case.....reach a temperature below freezing, attempting to charge them will permanently damage the battery.  (Not the air temperature...the temperature inside the battery).  Many lithium batteries have a "low temperature charging protection" circuit (inside the battery attached to the battery management system) that will cut off any charging going to the battery when the inside the battery is less than 32F.  Even with the charging cut off, the battery can be used to provide power.

The trick with the way the battery heaters are wired in the earlier versions of the Tabs with these heated batteries is: the heater switch is wired directly to the battery.......and the battery switch has no bearing on whether the heaters work or not.  Since the heaters are connected directly to the battery, Battleborn points out in the literature on these that if you have a Victron Shunt, the amp hours used by the battery heaters are NOT counted by the shunt.

Sounds like this another episode of "Funny Things Dealers Make Up On The Spot".

When you say your "lithium batteries are not showing 100 percent?"  Can you show us your Victron app status page?  Have you looked closely at your Battery settings page and made sure you are set up to charge lithium batteries with the solar?  (We have seen many many trailers from the dealer incorrectly set up).

Since the 360 is new, anything you can show us about the battery setup will be useful.  You may have a different model of battery or a different wiring setup for the heaters.  This is a thread from a couple of years ago that discusses the battery wiring and the wiring for the heaters to the battery heater switch.  It would be really good to know if this setup is different in the 360. 

https://tab-rv.vanillacommunity.com/discussion/17546/on-a-2023tab-400-what-is-the-small-red-wire-coming-off-the-positive-battery-terminal