When space allows, a large frame/case alternator is going to be better suited to LFP banks. They will still need some current limiting/derating & temp protection but they are purposely designed from the ground up, and intended for, driving large loads.


Small case alternators are adapted and modified for driving large loads for longer duration's but large case alternators were specifically designed for this type of duty from the ground up. Small case alternators will require more current limiting/derating to survive LFP banks than will most heavy duty large case alternators.


PHOTO: In this photo we have a large case alternator on a Balmar/AltMount custom bracket driven by a serpentine/rib belt. If you have the room, this is perhaps the best option to go with for charging LFP banks..


Image Courtesy C. Kelley