[QUOTE=jjue1979;4521285]I think that people were using 16V batteries (before LiFePo4 became popular) because they would sustain a higher voltage, especially with the improperly sized wires. With proper wiring size, even a 12V AGM can keep the voltage above 12.0V for longer periods of time, since dropping below 12V is the problem for a lot of electronics (even dropping below 12.5V is a problem for some car ECUs). Today's LiFePo4 batteries with proper wiring will definitely stay about 12.0V until the battery is just about dead.[/QUOTE

I rigged my boats electronics and used the proper gauge wire, you are correct about this, I have been running the Garmin for a good 6hrs on a 17ah lithium, so Im sure a 50 or 65ah 12v will suit me well.