battery short term storage question 3-6 months

[8milimeter]

My system will be unattended for usually 3 but up to 6 months.
My plan is to use a 365 day timer to charge every 90 days for a specified time period.
? How long should I charge (four) 12v 100ah in parallel with a 10-15 amp charger.
? which if any 110V 10-15 amp charger will let me adjust the max voltage to 13.2 V (70%)

 

[chrisski]

Because of your Avatar, I'm asuming you have lithium built from cells. Details will help.

I have not found a cell manufacturer answer for storing lithium cells built into a battery.

I decided to store mine at 50% charge, disconnected from everything except the battery monitor and BMS. I would have disconnected the battery monitor except it is wired before the switch. I was storing from heat which got to 105 F in the battery compartment.

I stored mine from April of last year to October with no issues. The year prior was four months.

IMO, the risk is less storing disconnected at 50% than having a charger hooked to it. I've had a trickle charger fail on a smaller lead acid battery and came back after several months to find it dead.