Lithium and Solar Upgrade +

[Karl404]

I’ve recently added 300 A-hrs of battle born lithium batteries, about 400 W of solar panels, 100 V solar charger and a 3000w inverter/charger to our 2021 Axis. (All victron components). We are two weeks into a trip and things are working pretty well so far.

I was a bit hesitant to overhaul my new RVs entire electrical system as a DIY project. I relied heavily on explorist.life videos and bought his detailed diagram. I’ll post some pictures at some point as parts location was the trickiest part of the install and might be interesting to those who might take on this project.

Question for those who might have done a similar project. I’ve got the RVMaster controller that now doesn’t tell me anything about my batteries/power and the victron apps that only control the power systems. I’d like to figure out a single control system. Anyone successfully integrated the two?

[DavidEM]

Sounds like you have a DC compressor fridge and need the amps from solar and the amp hour capacity of the Li batteries for dry camping.

Where did you put your three batteries. I replaced the OEM batteries under the step of my new Axis with two 100Ah AGMs, but no more will fit under there. The likeliest locations are in the long storage compartment aft and the small one forward of the step.

The BMPro RVMaster display and controller node are not compatible with any other DC additions unless you are into rewriting the BMPro code.

I use an inexpensive Amazon purchased shunt based battery monitor to see how many amps and amp hours I am using. It has been very useful in figuring out how the BIM 160 works and doesn't and how the WFCO converter doesn't work so well. I am replacing the WFCO with a Progressive Dynamics 9260.

See:https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1. Victron makes one for more $$.

David

[Karl404]

Our fridge can run off propane and we still leave it on propane unless plugged into shore power or during a really sunny day when the batteries are mostly charged.

I put the batteries, bus, and solar charge controller in the storage compartment under the bed on the drivers side. The inverter/charger is in the adjoining rear storage compartment. The under step compartment may become shoe storage.

I’ve got a Victron battery monitor and came to the same conclusion that it doesn’t play with RVMaster.

[DavidEM]

OK, surprised you need all of that solar power and batteries with an absorption fridge like mine. I use about 35 amp hours daily as long as i don't run the furnace.

You might want to check out your BIM 160. It is underneath the hood on the driver's side near the wheel well. It was wired incorrectly by Thor. Judge on this site pointed this out to me. See https://www.thorforums.com/forums/f1...0-a-26220.html

When I flipped the wires back and forth from A to B the isolator immediately engaged and the chassis alternator charged the coach batteries even when my 200 Ah AGM batteries were mostly charged. Before I flipped them it would only charge when the batteries were down to 50%.

How you make this work with Lithium batteries is another story. You may overload the chassis alternator with the low charging impedance of the Li batteries. Precision Circuits makes their Li BIM 225 which supposedly cycles the connection off and on to put less stress on the alternator. It is a direct replacement for the Thor installed BIM 160.

A better solution may be a DC to DC charger.

David

[Karl404]

I’ve got the BIM 225 sitting in a box at home. I ran out of time before we needed to leave on our current trip. I did disconnect the existing BIM. Thanks for the heads up on the wiring. I’ll make sure I don’t repeat Thor’s mistake when I replace the BIM.

[DavidEM]

That will be a long wiring run from the BIM location to where you put your new battery bank. The OEM wiring to the under the steps location is #2 wire. I would also use #2 for the new wire run, but it will be much longer probably twice as long which is good in a way because the additional voltage drop will limit the current that the fixed voltage alternator can put out.

The OEM wire doesn't have a breaker or fuse at the coach's battery to protect the circuit but I would put a 200A fuse near the coach batteries.

David

[Karl404]