question

I have been doing exactly that in our motorhome for the last 7 years of fulltime travel with an Argo Diode 120A unit solely to slightly lower the alternator voltage to our 300Ah 4 cell LiFePO4 battery.

It drops the maximum output from 14.4V to 14.1V with the added benefit of reducing the stress on the 100A rated alternator from 85-90A to 70-80A and despite all the naysayers no smoke yet.

The voltage drop obviously remains virtually the same with 1 or 2 diodes in parallel and the current handling should be better but they may not share it equally usually due to the fractional forward voltage drop differences.

Dear scubadoo, thank you for your answer. I'm using these Argo Diode Battery Isolators only as "one direction current only"-units to be able to combine AGM-batteries with lithiums. Both types of batteries have their own Argo Diode Battery Isolator. When not using the outputs in parallel, to be able to use the full 2 x 160 Amp, I need to split the charge and connect both types of batteries with two cables in stead of one cable (of course, with one cable, it isn't the whole 2 X 160 Amp but I can do with less than that in my vanlife camper).