WHAT IS THE DIFFERENCE BETWEEN A CAR BATTERY AND A DEEP CYCLE BATTERY?
Both car batteries and deep cycle batteries are lead-acid batteries that use exactly the same chemistry for their operation. The difference is in the way that the batteries optimize their design:
A car battery is designed to provide a very large amount of
current for a short period of time. This surge of current is needed to turn the
engine over during starting. Once the engine starts, the alternator provides
all the power that the car needs, so a car battery may go through its entire
life without ever being drained more than 20 percent of its total capacity. Used
in this way, a car battery can last a number of years. To achieve a large amount
of current, a car battery uses thin plates in order to increase its surface area.
A deep cycle battery is designed to provide a steady amount of current over a long period of time. A deep cycle battery can provide a surge when needed, but nothing like the surge a car battery can. A deep cycle battery is also designed to be deeply discharged over and over again (something that would ruin a car battery very quickly). To accomplish this, a deep cycle battery uses thicker, denser plates.