Originally Posted by dannc
Because LiFePo batteries can take a huge amount of power quickly, I wonder if one can size the battery bank with one or two alternators that would properly load the main engine at anchor.
How much charging current capacity do you want? 800A, say? That would be a lot. (I suppose you could put together an 800A 12V system using belt-driven alternators but it wouldn't be cheap.) It would give you a 4C rate for a 200Ah LiFePO4 bank, or 2C for a 400aH bank, which they are supposed to be able to absorb. But that is only about 10 kilowatts, or around 13 horsepower... not really a load on a typical trawler propulsion engine.
The theoretical advantage of high charging rates for LiFePO4 cells is hard to realize in a marine application, IMO.