Deep Cycle Marine Battery: Working and Benefits

A deep-cycle marine battery is the kind of battery that you can discharge and recharge with ease. You can measure discharge by the capacity removed from the battery. The depth of discharge indicates how much battery capacity you used in one discharge. These batteries are useful for golf carts and RVs. But based on their design, you can use deep-cycle marine batteries for boats and yachts only. And you must have to maintain the batteries to maximize their lifespan. You must check the voltage and fluid level of the batteries right after charging them.

Let’s look at what a deep-cycle marine battery is, how it works, and benefits the users.

What is a Deep Cycle Marine Battery?

If you are unfamiliar, these batteries look more like car batteries at first glance. But they are quite different. These lead batteries provide power for longer periods of time. They also run well until they discharge up to 80%. It is the time when you have to recharge them. Though you may discharge the battery up to 80%, manufacturers recommend not to let it go below 45%. Otherwise, the battery’s health will be affected, which is not what a user wants.

Deep-cycle marine batteries are different. They don’t discharge as fast as other batteries. For example, if you use a simple battery, it’ll discharge by 2 to 5% with a single use. But these batteries last longer than usual and have more incredible lifespans.

Types of Deep Cycle Batteries

Following are some of the types of deep-cycle marine batteries:

Flooded Deep Cycle Battery

It is the most common type of deep-cycle battery. These batteries are cheaper as compared to others. But you have to maintain them quite often. For example, you will have to add distilled water to its electrolyte to make it work in an efficient way.

Gel Batteries

This battery requires you to add gel to its electrolyte. That makes it more dense and thicker. As a result, it prevents the battery from any leakage.

Sealed Deep Cycle Batteries

People also call these maintenance-free batteries because of various reasons. You don’t even need to add distilled water to this battery. It is the reason why you can maintain them with ease. But, a sealed deep-cycle marine battery is an expensive option.

Lithium-ion Batteries

These batteries are the most recent type of deep cycle batteries. They have various applications in different fields. Also, their performance is better than traditional lead-acid batteries. They have lesser weight and a longer lifespan than the latter. Also, you can discharge them without damage, which is not the case with most batteries. But they are expensive if you compare them with lead-acid batteries.

Absorbed Glass Mat Batteries

These batteries have a glass mat for absorbing the electrolyte. That is how the even distribution of the electrolyte occurs throughout the battery. It helps to increase the lifespan of these deep-cycle batteries. All these types of deep-cycle batteries are in use at the moment. You may also use them for household and business purposes.

Components of Deep Cycle Marine Batteries

Some of the batteries mentioned above have identical components. But the important ones for deep cycle marine batteries are:

Lead Plates

It is an active part of the battery. It reacts with electrolytes to produce power or electricity.


The case’s primary purpose is to hold all the components and protect the battery. Without casing, the battery may get exposed to environmental conditions, affecting its lifespan.


It is a mixture of water and the king of chemicals, i.e., sulphuric acid. It carries the reaction between lead plates by conducting electricity. 

Benefits of Deep Cycle Batteries

Whenever you plan to buy a battery, the only thing you think of is what you will use it for. Also, you see what specifications the product is having which can benefit you. Here are some of the applications and advantages of deep-cycle marine batteries:

Suitable for Variable Conditions

These batteries prove to be useful even in conditions when the temperature is high. But, the type of battery may vary depending on the conditions. For example, if the power need varies, a VRLA battery will work well since its sealing is fine. So there is no chance of damage to any of the inside components. It also ensures a longer lifespan of these batteries.

Apart from that, you can also make VRLA batteries work in any orientation. Even though you should install them in the right way, they will work even if you don’t do so. This benefit makes people choose this option.

Stationary Equipment

If you don’t use your yacht quite often, it remains stationary most of the time. Under such circumstances, you must use a flooded deep-cycle battery. These are also the most common types of deep-cycle batteries. They are cost-effective as well, and you can find them with ease. It is a significant advantage of them over any other battery.

If you don’t use your yacht quite often, it remains stationary most of the time. Under such circumstances, you must use a flooded deep-cycle battery. These are also the most common types of deep-cycle batteries. They are cost-effective as well, and you can find them with ease. It is a significant advantage of them over any other battery.

You can only use the battery upright since it uses a liquid electrolyte. You may also use them in applications where you can charge them with ease. At times, marines remain underwater for more extended periods. So it becomes difficult to charge these batteries. Or if they malfunction at any instant, there is no way you can replace them. So, be careful when choosing to use these deep-cycle marine batteries.

Maintenance Capability

Most batteries need regular maintenance. This is a hectic and complex part of their usage. So, it would help if you chose options that need less or no maintenance. And since you have to charge batteries so often, you must also take good care of them. And if you cannot do that, you must buy the ones that need no maintenance.

One of the examples of a deep cycle battery is the one in your phone. You charge your phone once and use it all day long. Also, you instruct the battery when to use it by unplugging the charger. Some users only charge the phone when dead, which is not a good practice. Playing within safe limits is a better option. You must do the same to a deep-cycle battery.

Precautions Before Using a Deep Cycle Marine Battery

You must take specific precautionary measures before using a deep-cycle marine battery. Here are some of them:


Safety should always be your top priority before using or handling anything. Before troubleshooting a battery, you must know what hazards are there. For that, you must wear proper personal protection equipment. Also, you have to remove metallic objects if you have worn any. To get an idea about the accurate reading, charge the battery to its full. If it’s impossible, allow it to rest for an hour or so after use.

Look for Damage!

It’s not a big deal to find out the problem with your battery. But you have to look carefully for it, and you don’t need extraordinary skills either to do it. You can detect any problem by checking the following:

Leakage Issue

If you use a flooded battery, a leakage will indicate the case is not healthier. You can operate the battery even with a damaged casing. But that is dangerous since it can cause the whole battery to deteriorate. So, if you find any leakage, rectify it in the first place.

Dirt Accumulation

During inspection, don’t forget to check for dirt accumulation at the top of the battery. This accumulation doesn’t let the equipment work. You may have observed the same in the case of solar panels. Whenever the dust accumulates, panels don’t come in contact with sunlight. As a result, their efficiency decreases.

In this case, dirt may cause the battery to discharge itself when you are not using it. For that purpose, you must keep removing dirt or any corrosive particles from time to time. It is important to increase the efficiency of the equipment.

Loose Terminals

You may end up witnessing short circuits if there are any loose terminals or connections. So, if you find loose terminals, tighten them.

All these preventive measures are essential since they don’t let you experience any mishap. There is always a chance of anything happening at any moment in electrical circuits. And you can’t even stop that once it has occurred. So, safety is your top priority. And you have to keep it in mind.


Deep-cycle marine batteries have various advantages over conventional batteries. They use electrolytes to conduct electricity. Therefore, they’re suitable for various applications. This includes EVs, golf carts, and boats. All you need to know is when to charge and operate it. Leave the rest on the equipment.

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