How will i know when my battery is full

[highwayman]

Hi folks
I want to fit a smart shunt but have to tell it if my batterys are full or flat apparently.
Thing is how will I know ???
I've no gauge of anything else to tell me apart from my smart mppt controller which is currently showing
13.77 v 4.90 amps going in from my solar panel and is in Absorbtion mode.
Does anyone have any ideas please. ??
Cheers nige

 

[Badknee]

If it’s smart enough it should know and then dissipate the excess leccy I would think like the regulator in the alternator does.

 

[autorouter]

If you have a smart mains charger, when the battery is 100% full it switches from absorption to float charging. The smart MPPT controller will do the same, except that obviously the supply side depends on the sun, so might stop and restart several times. So if the charger is in float mode then the battery is 100% full.