I'm not so sure that an automotive battery is the answer. 14.8 volts is a fairly high charging voltage. I would recommend you review the following document.

A GUIDE TO BATTERY CHARGING

An excerpt from that is "Although a battery is called a '12 volt' battery, its voltage varies from about 12.6 volts down to 10 volts when it is discharging and can rise to 15 or 16 volts during charging. It is very important, however, to limit the maximum battery voltage during charging otherwise the battery will be damaged. The battery voltage should not exceed 13.8 volts for long periods and 14.4 volts for short periods (8 hours maximum)"