Lion lithium batteries

[mchurch314]

I replace my AGM batteries with two 125ah Lion lithium batteries in my 2019 Montana 3791r. I haven't plugged into shore power yet because a guy told me the stock converter switch may not be smart enough to stop charging them when it hits the upper end of 13volts. Anyone have any thoughts before I plug in and potentially overcharge my new batteries?

[RMcNeal]

I have a 2019 3791RD also. My converter doesn't have a switch for lithium, but as I understand it, it's the other way around. Lithium batteries want higher voltage to fully charge, and my converter won't output that higher voltage so it will never fully charge the batteries without intervention. I've read you can push the mode button on the charge wizard and put it in bulk charge longer so that it could charge them, but I haven't gone lithium, at least not yet, so I don't know for sure. I don't think it will hurt the lithium, just won't get a full charge on the standard charge wizard mode.

[mchurch314]

RMcNeal...thanks for the reply. I accidently posted this question twice. A couple guys on the other thread said the same thing, undercharging is more likely (which will actually increase the batteries longevity). How undercharged is yet to be seen. Where is Charge Wizard located? The button? I'm not sure I have this capability.

[RMcNeal]

On mine, there is a button on the converter inside the camper's electrical panel at the doorway. You should also see an LED light indicating the mode.

[Daryles]

It's the little black button next to the green blinking light.

https://www.montanaowners.com/forums...onverter+reset


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 to prevent damage to the battery.

[mchurch314]

Daryles....thanks for the followup!

[Foldbak]

Dam I was wondering what that was for! Thanks for teaching old dogs new tricks!

[bcrvman]

Originally Posted by mchurch314

I replace my AGM batteries with two 125ah Lion lithium batteries in my 2019 Montana 3791r. I haven't plugged into shore power yet because a guy told me the stock converter switch may not be smart enough to stop charging them when it hits the upper end of 13volts. Anyone have any thoughts before I plug in and potentially overcharge my new batteries?

Well that 'guy' is totally clueless. Lithium and Lead both charge to 14.4 +- 0.2

[allenclme]

Originally Posted by mchurch314

I replace my AGM batteries with two 125ah Lion lithium batteries in my 2019 Montana 3791r. I haven't plugged into shore power yet because a guy told me the stock converter switch may not be smart enough to stop charging them when it hits the upper end of 13volts. Anyone have any thoughts before I plug in and potentially overcharge my new batteries?

I have the same LION batteries. Their headquarters is here and I talked to the factory rep at an RV show and said that the progressive dynamics in my 3820fk won't fully charge the LIONS but it wouldn't hurt them. However, Progressive Dynamics makes a replacement converter charger for lithiums that I plan to get. For now, I only use the lithiums with a portable solar panel for off-grid. I still have the flooded golf cart batteries for on-grid. Kind of a hokey setup until I update the converter/charger.

[PNW Fireguy]

While you are correct that the stock converter will not fully charge the Lion Safaris take splice in realizing that by reducing your max charge setpoint you are increasing the overall life of those batteries. Half full

[RMcNeal]

So the lithium batteries are similar to the lithium batteries in a cell phone, in that ideally charging them to 80-90% and running down to 30-40% is a way to maintain optimal battery life?
I kind of understand the whole "charge cycles" limitation of lithium batteries, but not sure how the cell phone batteries compare to these 12v lithium in an RV.
We do not boon dock and have no use for the additional battery capacity so I haven't gone for lithium and likely never will, but it's good to know info either way.