Upgrade to Lithium

[Lloydt512]

2022 3121RL Legacy with 400i solar. I’ve read all I can find about upgrading to Lithium batteries but I still have a new guy question. On the Converter Charger should be a switch to select between Lead Acid and Lithium. Where is the Converter Charger? I think it may be behind the panel cover on the circuit breaker panel near the stars, but not sure. Also read that the Victron
Smart Solar Charge Converter has a selector switch, with Position 7 used for Lithium batteries. I think I’ve found this converter in the basement storage area but have not looked for the selector switch. Planning to make the upgrade in 2 days so trying to get prepared. Thanks for your help.

[Daryles]

Yes, the removable/upgradable converter is integrated into your circuit breaker panel (circled in red) held in by two screws.
Yes there is a "FLA" (flooded lead acid), "Li" (lithium) switch (circled in yellow). You must remove the cover to see it.
Download the manual from Progressive Dynamics. You model number is on a white sticker on the cover
Example PD4575K18LS8

You can download the manual for your solar MPPT from Victron. Also download the Victron Connect app to your phone and pair them together. Then you can control the MPPT and BMV-712 (battery monitor) from your phone.

[Lloydt512]

Thanks Daryls. Exactly what I needed.

[Lloydt512]

Daryles, thanks again, couldn’t figure how to correct the spelling

[214skier]

Is it just as simple as installing the batteries and changing the switch from FLA to LI?

[AZ Traveler]

Originally Posted by 214skier

Is it just as simple as installing the batteries and changing the switch from FLA to LI?

That's it. If you don't have a lithium capable converter you can still use lithium but they will only charge to 80% or so.

[RMcNeal]

Can you use the bulk rate on the charge wizard to get it any higher than 80%?
I'm also considering lithium when my GC-2 6 volts give up. My converter doesn't have the lithium switch.

[Daryles]

Originally Posted by RMcNeal

Can you use the bulk rate on the charge wizard to get it any higher than 80%?
I'm also considering lithium when my GC-2 6 volts give up. My converter doesn't have the lithium switch.

Yes, you can use the "Charge Wizard" to boost the batteries to almost 100%.
Last summer we spent three months dry camping in the Canadian rockies at Banff and Jasper NP.
The tall trees blocked the solar panels so we had to run the generator. Generator hours were 8-9:30 am and 5-7pm. I set the Charge Wizard to boost mode to get the most I could into the batteries as quickly as possible. It worked very well.
I can't find the link to PD Charge Wizard functions but here is a copy FYI.


The Charge Wizard Operation
While the built-in Charge Wizard automatically determines which operating mode is best suited to recharge or maintain optimum battery condition, the Wizard Mode Button allows for manual override and has indicator light(s) to indicate the mode of operation.
NOTE: The Green LED on the left refers to the Charge Wizard - the Red LED on the right was for the Charge Sentinel (supplied on converters built prior to year 2000)
BOOST MODE – Indicated by green LED remaining on. The output voltage is 14.4VDC to rapidly recharge the battery up to 90% of full charge.
NORMAL MODE – When the battery is between 50% and 90% charged, the green LED will flash once per second. When the battery has reached
90% of full charge the green LED will flash 2 - 3 times per second. In this mode the output voltage is 13.6VDC and the*converter*is safely completing
the charge of the battery.
STORAGE MODE – Indicated by green LED flashing every 6 - 8 seconds. In this mode the output voltage has been lowered to 13.2VDC, the RV
battery is fully charged and the*converter*is maintaining the charge.
MANUAL BUTTON - The manual button has been provided to allow the operator to temporarily override the*converter*(not recommended) or to
verify the*converter*is operating properly. For manual operation, Press and Hold the button. The indicator light will soon remain “ON” indicating Boost
Mode. Continue to hold the button and the light will blink rapidly indicating the*converter*is in the Normal Mode. Continue to hold the button until the
light blinks slowly indicating the*converter*is now in the Storage Mode. After the manual button is released the*converter*will stay in the selected mode. When the battery charge status changes, the*converter*will return to the automatic mode of operation after 4 hours to prevent damage to the battery.

[214skier]

Originally Posted by AZ Traveler

That's it. If you don't have a lithium capable converter you can still use lithium but they will only charge to 80% or so.

Great news, my converter has the LI switch. I ordered a set of batteries. My use case is this--we will need to run a few lights in the evening and service the furnace fan overnight until we can turn the gen on in the AM. Do you think that is realistic goal?

[Daryles]

The furnace draws about 12A.
How long it will run on batteries depends on the outside temp, the temperature you set on the thermostat and the battery capacity you have.
For example FLA batteries have only 50% usable capacity (down to 12vdc approximately) before you begin to deplete their capacity (shorten their lifespan).
So a 100Ah FLA battery will run the furnace about 4 hours continuously before dieing.
Lithium batteries you can run all the way down, although I don't recommend it. I try to stay between 10-90%.
A pair of 100Ah Lithium batteries should get you through the night.

Excellent article on Lithium batteries
Just be aware of using them at freezing temperatures.

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

[214skier]

I really appreciate the great advice.

[2Wanderers]

How do you handle Lithium batteries when it gets down to or below freezing?

[Daryles]

Originally Posted by 2Wanderers

How do you handle Lithium batteries when it gets down to or below freezing?

Using (discharging) lithium batteries at or below freezing temperatures is no problem.
However, CHARGING a lithium battery who's internal temperature is at or below freezing will destroy the internal chemistry of the battery cells.
MOST newer lithium batteries have built in BMS (battery management system) which will prevent charging at freezing temperatures. Check the manufacturer data specs before you buy.
I made battery heaters using RV holding tank heating pads.

https://www.montanaowners.com/forums/showthread.php?p=1255190#post1255190

[Lloydt512]

Installed Lithium batteries in my 2022 3121RL today and what should have been an easy job turned into real chore. Could not get the cover off the battery box. And yes you guessed right, I have not checked the water in the batteries since we purchased last August. I tried once but gave up when I couldn’t get the cover off. We had to cut the corner off the cover where it was trapped under the hydraulic reservoir. What a poor arrangement. Looks like the batteries were installed then the reservoir was bolted in on top. Only other difficult task was setting the Solar Charge Controller to position 7. Hard to see the tiny switch under the controller. Thanks to those who provided help.