Because starter batteries are primarily used to start a vehicle’s engine, most are rated in Cold Cranking Amps (CCA). CCA is defined as the number of amperes a battery can deliver at 32°F (0°C) for 30 seconds while maintaining at least 1.2 volts. In other words, the higher the CCA rating, the stronger its cranking ability (and the opposite is also true). There is no direct correlation between a battery’s CCA rating and its amp-hour storage capacity. Starter batteries use thin plates to achieve low internal resistance and maximize surface area, allowing for maximum current flow.

While starter batteries are primarily designed for starting engines, deep cycle batteries are built for continuous power. They are commonly used in marine, golf cart, and industrial equipment applications. Instead of being configured for high-energy bursts, their purpose is to provide maximum capacity. This increased amp-hour capacity comes from using thicker plates, making them ideal for deep cycling and long cycle life. Although designed for deep discharges, taking these batteries below 80 percent DoD (depth of discharge) can still shorten their lifespan.