If the batteries are charged, and no loads taking power, it would be normal to have 110v on the solar pv input side. It just means the charge controller isn't letting current flow through, so the pv modules output their open circuit voltage (voc)
Your low voltage disconnect suggests that the batteries aren't full. Maybe your charge controller is staying in Float, and the rebulk voltage is too high?
Are you using custom voltages or preprogrammed ones? Does the tristar have a setting for lithium? I have one in the basement running, but I don't remember anything about lithium settings. I have lead.
Also, what is your low voltage disconnect set at?