Batteries will last a lot longer. A typical warranty is 5 years but you can get 7 or 8 years of productive lift from a battery. If you are not doing the above a battery may only be productive for a year or two and then it is under performing, with all the attendant unnecessary time, labor and expense, for the last few years it is in use. You incur the consequences of increased charging, lost productivity and unnecessary electricity and labor expense to keep them inservice.