You didn’t say how you are determining state of charge…Determining SOC with lithium (LiFePo4) batteries can sometimes be problematic due to what is an uber flat voltage discharge curve, and I would think that running a CPAC is mission critical…Do you have a lithium capable SOC (state of charge) meter such as a Victron Smart shunt, or a BMV-12 or equivalent?? …If not, then it’s gonna be difficult for you to know what your true SOC is - voltage alone may not be telling you the whole story…
Outside of that, when your battery is undergoing a charge, you’ll need to see a voltage at the terminals of somewhere around 14.2 to 14.6 v and holding to achieve a full charge, yet this will occur prior to a passive internal cell-balancing regime which can usually take (depending on number of less than full charge battery cycling) say another 15-30 min or so - this phase can be readily monitored on your SOC meter via intermittent amps vs volts until holding at near zero amps (assuming no load)…After this, it is best to discontinue longer term charging to avoid the possibility of dreaded dendrite formation that may occur due to such overcharging…
3 tons