When Should I Use a Deep Cycle Battery?

Our topic today is deep cycle batteries. Deep cycle batteries are batteries that are designed for discharging and recharging such as in RV application, golf cart, floor scrubber, or electric vehicle. Deep cycle batteries as a rule should not be discharged below 80% depth of discharge. So, if a batteries rated at 100 Amp Hour as a rule we should not remove more than 80 Amp Hour from that battery or we're going to damage the battery and we're not going to get as many cycles out of it. 
 
Ideally, a deep cycle battery should not be cycled below 50% depth of discharge. This is when we're going to get our maximum number of cycles. So, as a rule of thumb, the deeper you discharge a battery the less cycles that it's going to deliver. So, in applications such as off-grid or off-cottage applications typically we size a battery bank to 50% depth of discharge so that we get the maximum number of cycles out of that battery. 
 
In mobile applications, such as RVs and other things like that, it might not be possible to size that battery bank so that you only run it to 50% depth of discharge because we're going to have to add more batteries. Deep cycle batteries are rated in reserve capacity minutes or Amp Hour. Reserve capacity minutes is a measurement of how many amps the battery will deliver. Amp Hour, on the other hand, is a rating over (typically) a 20-hour period. So, if a battery is rated at 100 Amp Hour that means it will deliver five amps for 20 hours. 
 
Internally, deep cycle batteries have thicker plates than starting batteries. Thicker plates are a result of batteries requiring more cycling. So, every time we discharge that battery, or we discharge that plate, we shed a microscopic amount of active material off the plate. So, essentially if we have a thicker plate, we should get more cycles out of that battery because it's going to handle active material shedding better. 
 
Deep cycle batteries can be used in starting applications but they deliver less power. They deliver less power because they're not built for starting. They're built to deliver a smaller amount of pure power over a long period of time unlike a starting battery that's designed to deliver a big burst of power over a short period of time. 
 
So, for more information on deep cycle batteries and lead-acid batteries, visit us at cdnrg.com. And, check out our video on this subject here: https://goo.gl/UMG8MX

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