The 110Ahr Lead acid buffer batt isn't available capacity for normal use. It is kept fully charged and acts as a load to keep the alternator stable. A LiFePO4 batt has more usable capacity. 80% of the rated capacity, vs 50% for Lead acid, without seriously degrading the Lead acid life. The 110AHr capacity of each Lead Acid is only when new and degrades, depending on number of deep discharges and recharges. It will carry on losing capacity, till it is so low you get fed up and replace it, which will soon be less than a Lithium one. I'd say about 200Ahr of Lithium is equivalent, or better than 3x110 of new Pb Acid batts. A 105Ahr Li will still be good when the 3x110Ahr Pb acids have much less usable capacity.
