2022 Montana Inverter Charger for Lithium

[K2 Camper]

I have a 2022 3761 FL and I want to change the lead acid batteries to lithium. Is my rig inverter charger compatible with lithium or do I need to change it to be compatible with the lithium batteries? How can I tell if my rig is ready to just add the lithium batteries?

[K2 Camper]

I think I found my own answer in the owner's manual. It says the following:

If equipped, the Power Center/Converter Charger has a Dip Switch to change battery charging capability from Lead Acid Batteries to Lithium Batteries. Please refer to the manufacturer's instructions for care and operation. If your Power Center/Converter Charger does not support charging Lithium Ion Batteries, the maximum charge a Lithium Ion battery can receive is approximately 80% of the total battery capacity.

Aftermarket all-in-one or stand-alone converter chargers are available in place of changing your Power Center/Converter Charger. Consult your dealer for more information on making sure your batteries are sized properly to meet
your specific camping needs.

[Carl n Susan]

If your converter is Lithium capable, there will be a small switch by the green blinking light to switch from LA to LI. It changes your charging profile to lithium


OPTIONAL OUTPUT MODE SWITCH:
The optional OUTPUT MODE SWITCH sets the converter output to either a constant 14.6VDC with the Charge Wizard® disabled (switch in ‘LI’ position) or a nominal 13.6VDC with full Charge Wizard® function (switch in ‘LA’ position). ‘LI’ mode is intended for use with lithium batteries with a BMS requiring a constant converter output. ‘LA’ mode is intended for use with lead/acid batteries where the Charge Wizard® will optimize battery charging.
NOTE: The OUTPUT MODE SWITCH should only be switched when new batteries are installed.
Verify battery type before adjusting the output mode switch.

[Todd & Mary]

We have a 2021 3761 FL. There is a small switch in an opening by the flashing green light on the converter. If you shift it to the other position, it will be setup for lithium.

[jdvier]

I have a 2011 3400RL. I am thinking about converting to lithium batteries. Due to the age of the unit will I need to replace the inverter?

[Carl n Susan]

Originally Posted by jdvier

I have a 2011 3400RL. I am thinking about converting to lithium batteries. Due to the age of the unit will I need to replace the inverter?

Yes, you will have to change the CONVERTER (you don't have an inverter)

[Daryles]

Originally Posted by jdvier

I have a 2011 3400RL. I am thinking about converting to lithium batteries. Due to the age of the unit will I need to replace the inverter?

Not necessarily...
I installed lithium batteries 3 years ago. My converter is NOT lithium ready however by using the "Charge Wizard" button (next to the green flashing light) I can get the lithium batteries to about 90%. I added solar panels later and the MPPT is set to lithium which tops them off.
I like to operate them between 20 and 80%.
They will last longer. I charge them to 100% when boondocking.
Good article on lithium batteries. If you run them between 20-80% they will last longer than your rig...

How to find happiness with lithium batteries
https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/

[bcrvman]

Originally Posted by K2 Camper

I have a 2022 3761 FL and I want to change the lead acid batteries to lithium. Is my rig inverter charger compatible with lithium or do I need to change it to be compatible with the lithium batteries? How can I tell if my rig is ready to just add the lithium batteries?

If you will also be installing an Inverter, make sure it is an Inverter/Charger and then totally disconnect your existing built in converter, and I mean TOTALLY at the converter supply side so it does not waste power, turning off it's breaker does not do that. I have no idea how many LiFePO4s you plan to get, but if it's 4 or 6 then the new Victron Multiplus II is the best solution. Obviously you will also want the Battery Monitor and the CERBO + Display option
Here is the Inverter/Charger link, the other parts can be found close by.
https://www.victronenergy.com/invert...lus-ii-2x-120v