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The difference between deep-cycle and starting batteries lies in the lead plate construction. Deep-cycle batteries have solid lead plates that are much thicker than the sponge lead plates in starting batteries. The sponge construction in starting batteries provides more surface area, which results in more cranking amps. Cranking amps are the amount of current a battery can produce at 32 degrees Fahrenheit. The more cranking amps a battery has, the easier it is to start the engine.
Starting and deep-cycle batteries are designed for different applications and conditions. While both may be used in boats, starting batteries should be used for starting the engine whereas deep-cycle batteries provide fewer cranking amps.
Batteries that are to be used in boats are usually hybrid batteries, a combination of deep-cycle and starting batteries. Their construction incorporates both thicker plates than traditional starting batteries, but the plates are also porous to produce more cranking amps.
Golf Cart Batteries
Electric golf carts need a steady source of power that lasts for long periods. This is achieved by using deep-cycle batteries that are designed to be 80 percent discharged and then fully recharged repeatedly.
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Golf cart batteries are deep cycle batteries. Marine batteries are a hybrid combination of a deep cycle & starting battery.
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