I would suggest that the problems with the current set of batteries may have been caused by a failure of one of the batteries cells which resulted in a cascade failure rather than one caused by the charger. Certainly have the charging system checked out...but recognize that batteries do fail.
I would suggest looking at the Odyssey AGM type batteries for the future as they can accept charge amperage well in excess of their rated capacity which will result in much faster charge times. The Freedom 25 can supply 125 amps and you can deliver ALL that amperage into ANY Odyssey battery. Thus with a 450 amphour bank 50% discharged and needing a 225 amp hour recharge...you could be fully recharged with the Freedom25 in two hours.
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