Battery types are almost as diverse as their applications. Batteries themselves can be found in forms as small as the tiniest devices (like earbuds and hearing aids) up to those measured in acres (like those used for storing solar and wind renewable energy) and defined as landmarks. The charge cycle of a battery matters when we think of these devices. The battery itself provides power to some load (a device that needs power) to perform some work. Small batteries powering small devices that are used frequently have a different cycle from large devices that are used infrequently, and all variations in between make up the different cycles. The way a battery is charged, the way that it discharges to its load, and the battery’s composition of materials determine its performance and lifespan.
Deep cycle batteries have historically been associated with large loads such as marine or recreational vehicle applications. The term “deep” refers to how much it can be discharged. A battery that is deep can typically discharge to half (or more) of its charged state and recover to do it all over again for many cycles. Traditionally this term came to define large size and heavy construction of lead-acid batteries that had bigger components for its battery plates and volume of the battery overall. Devices that need to work all the time for marine applications, power supplies for municipal applications (like sump pumps and traffic signals), and electric-only vehicles (wheelchairs and golf carts) have all traditionally relied on deep cycle batteries to serve them and typically over very long lifespans and associated charge cycles.
Whether you are a traditional user for your marine or recreational vehicle or you are looking at options to store power from your renewable energy system for long periods and powering diverse loads, deep cycle batteries are often the go-to option for years of reliable service. Increasingly lithium ferrophosphate (LFP or LiFePO4) batteries are replacing standard lead-acid batteries as their costs become more comparable due to increased lifespan and decreased weight. When considering your replacement battery for that fishing boat or recreational vehicle, don’t forget to look at all your deep cycle battery options.