How to choose best Marine battery 2024

The best deep cycle battery is heavy-duty and valuable. If you have a solar panel system, a recreational vehicle, or any deep cycle battery application need, you must have it. However, it’s uneasy about picking the right one for your situation, especially for beginners. In this case, you might find it difficult and time-consuming to choose the right one for you.

The dual-purpose marine battery is a combination between a deep-cell and a starter battery, and is comparable to a motorbike battery in design. Internally, dual-purpose batteries feature a construction that allows them to be deeply depleted while also serving as starter batteries.

If you want to save money and space, consider replacing the deep-cycle and starter batteries with a dual-purpose marine battery, which can power both the engine and the appliances. Because it cannot deliver the same depth of discharge as a deep cycle battery or the same cranking amps as a starter battery, it is only suggested for medium and small boats with short voyages.

What Is A Marine Battery?

A marine battery is a specialized type of battery designed to provide power for marine applications such as boats, yachts, and other watercraft. These batteries are specifically engineered to withstand the harsh marine environment, including exposure to water, vibrations, and extreme temperatures. Marine batteries are essential for powering various electrical systems on board, including navigation lights, radios, fish finders, and trolling motors.

Marine batteries are different from automotive batteries in terms of construction and performance. While both types of batteries use lead-acid technology, marine batteries are built to deliver a steady amount of power over a longer period of time, whereas automotive batteries are designed to provide a high burst of power for starting the engine.

Different Types Of Marine Batteries

There are several types of marine batteries available in the market, each with its own unique characteristics and applications. Let’s take a look at some of the most common types:

Flooded Lead Acid Batteries: These are the most traditional and widely used marine batteries. They are affordable and offer good performance. However, they require regular maintenance, including checking and refilling the electrolyte levels.
AGM (Absorbent Glass Mat) Batteries: AGM batteries are maintenance-free and provide excellent performance. They are sealed, which means they can be mounted in any position without the risk of acid leakage. AGM batteries are highly resistant to vibrations and have a longer lifespan compared to flooded lead acid batteries.
Gel Batteries: Gel batteries are similar to AGM batteries in terms of maintenance-free operation and resistance to vibrations. However, they have a slower charging rate and are more expensive than AGM batteries.

What Battery Ratings to Look For

Starting functions: the amount of power available for cranking a starter is measured several ways.

CCA vs. MCA: The two common power measurements are CCA (Cold Cranking Amps, the number of amps a battery can deliver for 30 seconds at 0°F while maintaining its voltage above 7.2 volts) and MCA (Marine Cranking Amps, similar but measured at 32°F instead of 0°F). The reason that MCA are 20–25% higher than the CCA is because batteries work better at higher temperatures.

Reserve Minutes indicate how long a battery can sustain a load of 25 amps before it drops to 10.5 volts. A battery rated at 150 minutes can operate a 25A load for 2 1/2 hours (at 80°F). Starting batteries aren’t used to handle loads for long periods, so reserve minutes are less critical.

Size: Engine size, type, and ambient temperature determine what size cranking battery you need. High cranking power (and a larger battery) is required for cold temperatures, diesel engines, or large and high compression gas engines. The first sizing criteria is to meet the minimum CCA (if any) stated by the engine or boat manufacturer. If a Group 24, 550 CCA battery worked well for five years, we’d recommend replacing it with a similar model. If, however, it cranked too slowly or failed after a season or two, we’d suggest that you look for a battery with a higher CCA or MCA rating.

Deep cycle functions: Battery capacity measurements are commonly expressed in Amp-hours (Ah) and Reserve Minutes. Amp-hours measure the total amount of energy that a battery can deliver for 20 hours at a constant rate of discharge before the voltage drops to 10.5 volts. This means that a 200Ah battery can run a 10A load for 20 hours. The reserve minute rating is the number of minutes that a battery can run a 25A load until dropping to 10.5V, just like with starting batteries. A Group 27 deep cycle battery with a rating of 180 reserve minutes will run a 25A load for three hours. House loads range from 5A to 25A or more. Amp hours is generally the more relevant measurement for house banks.

Longevity: Battery manufacturers measure longevity by discharging full batteries at a temperature of 80°F until their voltage drops to 10.5 volts. The batteries are recharged under controlled conditions, and the process is repeated until the battery fails to hold half of its rated capacity. This measurement, called cycle life, shows how many discharge cycles a battery provides over its lifespan. This ability to cycle repeatedly is what differentiates deep cycle batteries from starting batteries, which can’t withstand more than a few deep discharges before they begin to fail. If nothing else, cycle life provides a baseline for comparing one battery to another.

Importance Of Choosing The Right Marine Battery

Choosing the right marine battery is crucial for the performance and reliability of your boat’s electrical system. Here are some key factors to consider when selecting a marine battery:

Battery Capacity: The battery capacity, measured in ampere-hours (Ah), determines how long the battery can provide power before needing to be recharged. Consider the power requirements of your boat’s electrical systems and choose a battery with sufficient capacity to meet your needs.
Battery Type: As discussed earlier, different types of marine batteries have different characteristics and performance. Consider factors such as maintenance requirements, lifespan, and cost when selecting the battery type that best suits your needs.
Charging System Compatibility: Ensure that the marine battery you choose is compatible with your boat’s charging system. Using an incompatible battery or charger can lead to inefficient charging and reduced battery lifespan.
Durability and Safety Features: Look for marine batteries that are designed to withstand the harsh marine environment, including features such as vibration resistance, corrosion resistance, and built-in safety mechanisms to prevent overcharging and short circuits.
Manufacturer Reputation: Consider the reputation and reliability of the battery manufacturer. Look for brands that have a proven track record in producing high-quality marine batteries.

Battery Tips for Best Performance

No matter what kind of battery chemistry you choose, follow the manufacturer’s recommendations to get the best performance. Note: The following recommendations apply to flooded, gel and AGM batteries.

Stay with one battery chemistry (flooded, gel or AGM). Each battery type requires specific charging voltages. Mixing battery types can result in under- or over-charging. This may mean replacing all batteries on board at the same time.
Never mix old batteries with new ones in the same bank. While it seems like this would increase your overall capacity, old batteries tend to pull down the new ones to their deteriorated level.
Regulate charge voltages based on battery temperature and acceptance (manually or with sensing) to maximize battery life and reduce charge time. Ensure that your charging system is capable of delivering sufficient amperage to charge battery banks efficiently. This generally means an alternator with an output that is 25% to 40% the capacity of your entire battery bank.
Keep batteries clean, cool and dry.
Check terminal connectors regularly to avoid loss of conductivity.
Add distilled water to flooded lead acid batteries when needed. Keep them charged. Leaving them in a discharged state for any length of time will damage them and lower their capacity.
Clean corrosion with a paste of baking soda and water.

FAQ

Are dual-purpose marine batteries any good?

Marine Dual-Purpose Batteries combine the performance of a starting with deep cycle battery, making them a viable alternative for smaller boats with limited space. They can execute the functions of both beginning with a deep cycle battery, although they aren’t as efficient as individual batteries.

What’s the difference between a dual-purpose battery and a deep cycle battery?

Deep cycle batteries, for example, are designed to tolerate multiple discharges and recharges, whereas cranking batteries are not. As a result, a dual-purpose battery falls somewhere in the middle. Many are unable to withstand entire discharges (discharge beyond 50 percent of usable capacity).

Which boat battery has the greatest life span?

When seeking for the longest-lasting marine batteries, consumers should be aware that AGM batteries, such as Brava batteries, can live up to three times longer than flooded lead-acid batteries.

What is the life expectancy of a dual-purpose battery?

Here’s how it’s done… When it comes to boat batteries, how long do they last? Depending on how well you care for your marine batteries, they can last anywhere from 2 to 5 years.

Is it possible to utilize a dual-purpose battery to power a trolling motor?

A dual-purpose battery can start and turn over the engine while also delivering enough energy to keep your trolling motor running constantly. Dual-purpose batteries, as the name implies, can be used for both functions. When combined with a trolling motor, they will deliver outstanding results.

What is the difference between a Marine Dual Purpose Battery and a Marine Single Purpose Battery?

Traditional deep cycle and starting batteries are both performed by dual purpose marine batteries. Over the course of a full day of fishing, these batteries should be able to start the outboard engine and provide enough juice to run the equipment.

What is the best way to charge a dual-purpose marine battery?

Check to see if your 12-volt constant current charger is switched off. Connect the red, positive terminal to the positive side and the negative, black terminal to the negative side. Bulk charging is the first phase of charging, during which you keep the charger amperage constant while the voltage of your battery rises.

What is the best way to store a marine battery for the winter?

Remove the batteries and store them somewhere cold and dry where they won’t freeze. (It’s best to use on wood surfaces in garages or storage buildings.) Ideally, charge batteries in stages or once a month. Self-discharge is avoided, and the lifespan is extended.

Is it possible to use a trickle charger with a marine battery?

Because trickle chargers do not generate excessive heat, they are ideal for maritime batteries. The battery heats up during a typical charge.

Is it AGM or gel in a deep cycle marine battery?

One crucial aspect to remember is that Lead-Acid batteries are employed in all deep cycle applications. This covers ordinary flooded, gelled, and sealed AGM batteries. They all use the same chemistry, but the plates, for example, are built differently.

What amperage should my boat battery be charged at?

Charge at a voltage of roughly 14.6 volts at a rate of up to 20% to 40% of the battery capacity in amp hours (gel: 14.1 volts). A 200 amp-hour battery, for example, would be charged at 40–80 amperes.