I have an IP22 12 volt charger configured with 250 AH of LiFePO4 batteries, and a smartshunt. I configured the charger for a long-term storage situation to keep the battery terminal voltage at 13.20 volts (about 50% SOC) while I am away in Europe. Upon installation of the charger, I noticed the output current from the charger was continually pulsing, but I attributed that to the 2 amp static load on my bus.
Now that I'm 7,000 miles away, and monitoring the VRM portal, I see that the charger is continually outputting 6 amps in pulses that raise the battery terminal voltage to 13.25 volts, and then charging stops until the terminal voltage drops to 13.18 volts (this is a normal LiFePO4 battery hysteresis range for charge/discharge at a SOC of about 50%). The pattern repeats about every 10 seconds, or about 9,000 times per day. My previous charger would just output 13.20 volts to support the static load, and not pulse-charge the batteries.
I am concerned about degrading the LiFePO4 batteries from memory effect brought on by shallow charge/discharge cycles. There will be millions of those cycles before I can physically access the system again. Am I worried about nothing?
The below graph doesn't show the true frequency of the cycles that repeat every 10 seconds, but it does show the voltage and current ranges:
