Hello, I have installed a 500a b/t smart shunt. I have a new 100ah LiFePo battery. Each day the smart shunt shoes the battery jumping back to 100% soc, at around 9am. This morning it had dropped to 77% overnight, then the sun got on the solar panel with the Victron mppt 100/20 and suddenly the soc reached 100% immediately. Have I got some settings wrong? Screen shot of history today and of settings.
Image Caption
@JonR have a look at this how to set up your BMV video.
Peukert factor is too high, charged voltage too low, and tail current should be lower. Charged voltage is your main issue. This should be set .1 volts below abs voltage.
The peukert is exactly what the video says, and certainly what victrons setup instructions say, and with the others. What do you suggest they should say?
In my experience the peukert for lifepo4 is actually closer to 1.01 but it partly depends on the size of the bank and the highest current draw expected. The charged voltage however is the cause of your problem. 13.2 is right around resting voltage for 12v lifepo4, and if you have solar this can cause premature full SOC calibrations. I don't know what your battery manufacturer specs for charging voltages but certainly 13.2 is way to low. Most people are comfortable with 3.45 to 3.55 volts per cell max charge voltage which would be 13.8 to 14.2. definitely don't go higher than 3.65 per cell. Say for example you set the abs volts to 14, then you want charged voltage set at 13.9 and tail current for lifepo4 can be set at 1%. If you set tail current too high and charged voltage too low you are not allowing any time for balancing at the top end.
