[JRTJH]

Most automotiive batteries have thin plates and relatively wide gaps between the plates. This allow them to discharge rapidly and to supply a large amperage for a short time. They are designed to discharge PARTIALLY and to be recharged before complete discharge (intermittent use) Their purpose is to provide large energy bursts needed to start cars/trucks, etc.

Most Deep cycle batteries have thicker plates and the plates are closer together. This allow them to have more plates in a specific sized area and to provide sustained discharge over a longer period of time and to discharge more completely before needing recharge. The plates, because they are thicker, don't warp as easily and will stand up to the heat/collection/discharge of electrons with more durability. Their purpose is to provide lower level energy for sustained periods of time. (Still, it is not recommended to discharge deep cycle batteries beyond 40-60%)

12 volt deep cycle batteries have 6 cells in a 6x7x11" (approximate) container. so each individual cell is about 6x7x0.8" 6 volt deep cycle batteries have 3 cells in about the same size container (or even larger). so each individual cell is about 6x7x1.8" (nearly 2 times thicker). That means the cells in 6 volt batteries are significantly larger, usually capable of storing more energy than a smaller cell size found in 12 volt batteries. Since the 6 V battery is designed to deliver low level energy for a long time, the plates can be closer together and still dissipate the heat generated by converting potential energy into electricity within the cells. ie: the ability to cool the battery is not as critical as in the automotive battery.

Sort of like a D cell battery will provide more energy than a AAA cell battery will provide, but both are 1.5 volts. The larger size cell allows for increased storage capacity.

There are other significant differences such as heat dissipation, recharge capability, plate construction, durability, etc, but essentially, 6 volt batteries have larger cells and can provide more energy per cell than most 12 volt batteries. HOWEVER, if an "ideal situation" where the 12 volt battery were exactly double the size of the 2 individual 6 volt batteries, so that the individual cells within the batteries were all the same size, the energy capability would be essentially the same between the 12 V setup and the 6 V setup. BUT: In that "ideal situation" The 12V battery would be able to provide a higher burst of energy than the 2 6 V batteries could provide (as was just described in the previous post) mainly because of the difference in plate thickness between the two differnet construction techniques.