How to Charge a Deep Cycle Battery?

deep cycle battery

Deep cycle batteries are great choices for applications where you need to store the charge for longer times and then have the battery slowly discharge. Deep cycle batteries provide a steady current over a longer period of time and that makes them great options for powering electronics. They are widely used in residential and industrial power systems to store electricity. They are the batteries you use with your inverter or UPS, and also sometimes in vehicles such as RVs and boats. 

While deep cycle batteries feature a lot of different functionalities, they are compatible with a wide range of systems and thus they can also be charged in different ways. But before we talk about charging of deep cycle batteries, let us look at the different charging stages that deep cycle batteries have.  

A deep cycle battery generally gets charged in three stages.the initial step is the bulk charge phase when the most amount of current is sent to the battery. After a while when the battery is mostly charged, the charging moves onto the absorption stage where the battery gets charged slowly until the battery is almost completely charged in which case it moves on to the trickle charge stage which is mostly done to maintain the battery charge at a 100%.

Keeping batteries properly charged is crucial if you want to get the best out of them. Batteries tend to get wasted if you leave them uncharged. A process called sulfation takes place in drained batteries that can affect their performance making them weaker and unusable.

The time taken to charge a battery depends on two factors. The capacity of the battery generally rated in Amp-Hours and the current rating of the charger itself. For example, a charger rated at 10amps will charge a 100AH battery in almost 10 hours. However, this does not mean that you can randomly pick the highest rated charger to charge your batteur. In fact, by doing so, you can end up damaging the battery altogether. Different battery types have different chargers and it is recommended to pick a charger carefully.

There are various types of chargers for deep cycle batteries. The most commonly used is the electric charger. Inverters and UPSs have built-in circuitry to automatically charge a discharged battery. But such sophisticated chargers tend to be expensive. Simpler chargers are also available that only charge the battery when prompted. You can select a suitable charger functionality based on your requirement and personal preference. 

Other than that, car batteries can also be charged using your car’s alternator. Although it is not recommended to use a deep cycle battery for cranking the car. You may have an additional deep cycle battery in the car to power additional electronics that the alternator can easily charge.

Lastly, one of the better and economical ways to charge a battery would be using a solar panel. 

12V solar panels can be used to charge batteries. Although, a charge controller is needed to monitor the amount of electricity flowing into the battery. Most charge controllers also have built in functionality to detect if the battery is fully charged and switch to trickle charging automatically. But again, such charge controllers are also quite expensive and we only recommend them if you need a powerful, robust and sophisticated system. 

One last thing you need to remember before getting a charger for your deep cycle battery is that not all chargers are compatible with all battery types. So be sure of your particular battery type if you are considering getting a new charger. 


In this article, we have discussed the various ways for you to charge your deep cycle battery. We hope you found the article helpful.