IP 65 500 AMP SmartShunt always returns to 100% SOC

I have a Bioenno 24 volt lithium battery ABS, BLF-2450AS and use it for a MinKota 24 volt Ulterra trolling motor

I have a battery cable that runs from the negative terminal on the battery to the battery minus on the shunt. That is the only cable connected to the negative side of the battery. Everything else that would normally be connected to the batteries negative terminal is connected to the shunt load minus, which is only the trolling motor negative and the charger cable negative. The trolling motor positive, charger cable positive, and the VBatt + are connected to the batteries positive terminal. I measured voltages and was getting 26.73 and 26.63. Later in the day after running the trolling motor on spot lock most of the time, I could see the battery percentage down to 91% in the victron app. As soon as I turn off the trolling motor it returns to 100%. I am at a bit of a loss as to why. Thank you.





You will have to set up the SmartShunt for Lithium batteries.

Have a look at the Manual and video and adjust your settings.

I have included a screenshot of my settings and read the manual. I believe the settings to be correct and don’t know what to change. Thanks for any advice.

Your charged voltage is too low, if you have a current below 0.5% x 50 = 0.25A at the same time as the voltage is above 26.4V it syncs to 100% which happens every time you turn the motor off. Increase your charged voltage to something like 28.0V or 0.2V below your absorption charge voltage.

I have SOC set at keep SOC and changed the voltage to 28 volts as you suggested. That seems to work. SOC showed 79% and stayed that way. Thanks!:pray:

There is a whole FAQ I wrote on this that I should have pointed you too if you want background reading.

shunt battery monitor jumping to 100…

Thanks for help and the additional info. I’m trying to understand this better. I “think “ I am getting good readings now. The trolling motor I use is powered up and down and I don’t want to get into a situation where I don’t have enough juice left to bring it up.