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There is a common misperception that charging one's battery banks faster is better or worth throwing more money at. Here are some reasons it is not always true:
Lead batteries have a maximum amount of current they will accept, typically C/3 for AGM and C/5 for flooded. So if you have 100Ah of AGM the most it will want to take is something like ~33A. Installing 50A-100A of charging capacity won't help the battery.1)
Lithium batteries can slurp up current wildly, but shouldn't for their own health. Lithium lasts longest in sub-C use (ie, less than 100A for a 100Ah Li bank). C/2 (50A) is a more common limit to keep from stressing them. In commercial examples the BMS will limit current to protect the cells. A small DC-DC charger can help protect bare cells from their own greediness.