I, too, have changed my RV off-season storage habits since switching to lithium coach batteries.
I now put the USE/STORE switch in STORE mode, rather than using shore power and the converter or an external charger to maintain the batteries. Even though our MH is parked in partial shade, the roof solar maintains the coach batteries daily (except when the solar panels are covered with snow or the cloudiest of days).
An added benefit: the LiBIM225 also, when sensing a sufficient voltage from the coach side, usually in late morning or about noon, also boosts the chassis battery (if it has self-discharged overnight below ~12.6V). If, by chance, the LiFePO4 BMS shuts down because of low temperature, the solar power is fully available for the chassis battery’s use.
My hypothesis: the daily solar cycle is beneficial to the longevity of both the lithium coach batteries and the almost 6-year-old OEM SLA chassis battery.
I have two 6 volt lead acid G.C. batteries with 150 watts of solar on the roof of our 5 th wheel connected to a victron mppt solar charge controller. The batteries remain in the trailer all year long and get very cold in the winter -40 C ~ and remain fully charged. I check for state of charge with a tri-metric battery monitor. Also there is a 4 position battery switch, 1 or 2, both or off.
The battery switch remains off for the winter but solar remains connected. The only hassle with this setup is occasionally sweeping off the snow that covers the panels! It all works very well!
I just found a useful data point: for a FLA battery at 50% SOC, freezing point is -4 F. And since we should never let our batteries go below 50%, I'm good to 0⁰ F under normal useage.
Since going to lithium batteries two years ago, my winterization scheme has changed drastically. I draw the batteries down to 70% (per tech support at Expion360),, shut off the power coming down from my solar panels, totally disconnect my batteries from any connection to the trailer 12v system (with two knife switches on the batteries), and turn off the converter. The only reason we leave the trailer plugged in is to keep our Dish box upgraded when Dish does upgrades. Otherwise it's a major hassle calling Dish to get our system up to date when we decide to take the trailer out. It gets cold here in northern Nevada so I don't want the system trying to charge the batteries when it gets below 32 degrees.
I, too, have changed my RV off-season storage habits since switching to lithium coach batteries.
I now put the USE/STORE switch in STORE mode, rather than using shore power and the converter or an external charger to maintain the batteries. Even though our MH is parked in partial shade, the roof solar maintains the coach batteries daily (except when the solar panels are covered with snow or the cloudiest of days).
An added benefit: the LiBIM225 also, when sensing a sufficient voltage from the coach side, usually in late morning or about noon, also boosts the chassis battery (if it has self-discharged overnight below ~12.6V). If, by chance, the LiFePO4 BMS shuts down because of low temperature, the solar power is fully available for the chassis battery’s use.
My hypothesis: the daily solar cycle is beneficial to the longevity of both the lithium coach batteries and the almost 6-year-old OEM SLA chassis battery.
I have two 6 volt lead acid G.C. batteries with 150 watts of solar on the roof of our 5 th wheel connected to a victron mppt solar charge controller. The batteries remain in the trailer all year long and get very cold in the winter -40 C ~ and remain fully charged. I check for state of charge with a tri-metric battery monitor. Also there is a 4 position battery switch, 1 or 2, both or off.
The battery switch remains off for the winter but solar remains connected. The only hassle with this setup is occasionally sweeping off the snow that covers the panels! It all works very well!
That’s a great setup…
Any comment on FLA batteries freezing even when fully charged?
I researched and wrote an article on that once. I’ll find it and repost later this week.
I just found a useful data point: for a FLA battery at 50% SOC, freezing point is -4 F. And since we should never let our batteries go below 50%, I'm good to 0⁰ F under normal useage.
And thank you, Mike, for your great articles!
Since going to lithium batteries two years ago, my winterization scheme has changed drastically. I draw the batteries down to 70% (per tech support at Expion360),, shut off the power coming down from my solar panels, totally disconnect my batteries from any connection to the trailer 12v system (with two knife switches on the batteries), and turn off the converter. The only reason we leave the trailer plugged in is to keep our Dish box upgraded when Dish does upgrades. Otherwise it's a major hassle calling Dish to get our system up to date when we decide to take the trailer out. It gets cold here in northern Nevada so I don't want the system trying to charge the batteries when it gets below 32 degrees.
So you have added another advantage to my list of advantages for Lithium batteries for RV's. Thanks
PS I hope Don (above) sees your post and stops charging his Lithiums when it it below freezing.
Oops! I just re-read Don's post and noted he has FLA batteries.