Marine Batteries vs. Car Batteries – Comparison Review [2019]

All batteries are not created equal.

Learning the ins and outs of marine and car batteries can help you better understand the way your vehicles and boats function and will give you the knowledge to make an informed purchase at the end of the day. 

This article will walk through some info on both batteries and our favorite picks in each category. 

Comparison Chart of the Best Marine Battery and Car Battery


Our Rating


​Vmaxtanks Vmaxslr125 AGM Deep Cycle 12v

Vmaxtanks Vmaxslr125 AGM Deep Cycle 12v 125ah SLA rechargeable Battery for Use with Pv Solar Panels,Smart chargers wind Turbine and Inverters

Best Marine Battery

​Odyssey 65-PC1750T Automotive and LTV Battery

Odyssey 65-PC1750T Automotive and LTV Battery

Best Car Battery

What is a Marine Battery?

A marine battery is one that is used to power a boat or trolling motor. They are commonly named or considered interchangeable with “deep-cycle” batteries. However, they are different. Marine batteries are used to start a boat’s engine, and once switched on, provide power to devices on the boat.

They typically will provide a short, higher intensity jolt of energy to start the watercraft, and as it is left on, will release a more gradual supply of energy that can be used to help appliances on the boat to function. The majority of marine batteries are dual-purpose, meaning they perform more than one function for the watercraft. 

Marine Battery Models

There are several different marine battery models to be aware of. Although some are much more commonly used than others, they all have their own advantages and disadvantages associated with them. Reading through the descriptions can help you decide which battery will be best suited for your personal needs. 

Flooded Battery

A flooded battery is one of the most commonly used on the market today. They’re versatile and come in all kinds of shapes and sizes. They function with the help of lead plates, a sulfuric acid electrolyte, and plate separators. They are unsealed and release gasses through external vents. Acid, steam, and condensation also flow through the vents, which need to be maintained regularly. They are often considered not as durable, but damage and corrosion can easily be combated with consistent maintenance. 

Gel Battery

Gel batteries are another popular model. They are sealed and use silica to convert sulfuric acid into a jelly-like substance. This new goo is used as the electrolyte in the equation. Gel batteries cannot be exposed to super high amperage, as it can cause internal damage over time.

The jelly can become scarred, creating a pocket within the gel, which paves the way for eventual corrosion. Although the internal construction is stronger in comparison to some batteries, it doesn’t have the overall power capacity that others have, as it can quickly fail when exposed to high amperage. 

Absorbed Glass Mat (AGM) Battery

AGM batteries are fairly new to the battery world. They consist of a fiberglass separator, lead plates, and an electrolyte. Capillary action is used to hold the electrolyte in place and create a physical bond. The capillary action keeps the liquid within the fiberglass plate.

The design is packed very tightly, making it very resistant to damage through the way of impact. The internal resistance is also very low, which has a plethora of benefits, including less charging time, increased power voltage, and less heat loss overall. 

What is a Car Battery?

A car battery is the power system used to start your car. Their main role is to provide the power to the engine to start up a car, but after that task is done, they do very little. For this reason, they’re called a cranking or starting battery.

A car relies more on the engine for power— once the vehicle is on and running, the engine provides the power to the electrical system and also charges the battery at the same time. 

Car Battery Models

There are several different battery models commonly used in cars. The battery you use will depend heavily on the style of your vehicle and your personal needs and wants for the tool. Each style has its own pros and cons associated with it, but familiarizing yourself with the overall functions of each can help you decide which battery would be the best pick for you. 

Starting, Lighting, and Ignition Batteries

The majority of batteries used in vehicles will fall under the starting, lighting, and ignition category. The primary task of these batteries can be gleaned from their name— they provide power to start a vehicle and give additional power to help your lights, radio and ignition function properly. They have a shallow charging cycle, which means they can only provide power in very small bursts of time. 

Deep Cycle Batteries

Deep cycle batteries are those that have more power over time than a starting or cranking battery. They are designed to provide sustained power rather than a short burst here and there, which makes them more suited for vehicles that require a continual power source aside from the engine. They work properly and reliably until they reach about 80 percent power. Although they can be run beyond that, it is recommended to recharge at that point to extend the life cycle of the battery. 

Valve-Regulated Lead-Acid Batteries

Valve-regulated lead-acid batteries were created to require less maintenance than a traditional battery. They don’t require water to be regularly added to the cells, a quality that is fairly uncommon when it comes to vehicle batteries. They are fully sealed, so they can’t be serviced, but rather have to be fully replaced if there is an issue. The two common types of VRLA batteries are absorption glass mat (AGM) batteries, which deliver high power in short bursts thanks to quick reaction time and gel cell batteries, which use a silica-based electrolyte as a power source.

Wet Cell (or Flooded) Batteries

Wet cell batteries get their name from the liquid that is used to create the battery’s electrolyte. It combines lead, water, and sulfuric acid. These models are often a much cheaper alternative to other batteries, but some aren’t as high-quality construction-wise. They also must be maintained regularly to replace any electrolytes that have been lost but are fairly easy to service. 

Lithium-Ion (Li-ion) Batteries

Although these are far and away the least common batteries because they are incompatible with many styles of vehicles, lithium-ion batteries have become much more popular in recent years. Cars like hybrids and electric cars use these batteries because they can store a significant amount of energy and are very lightweight, the perfect combination for eco-friendly vehicles. However, there is a huge drawback to these batteries as their lifespan is not up to snuff compared to the other styles on our list. 

Marine Batteries vs. Car Batteries - Similarities and Differences

Car and marine batteries share many common features but are also separated by all kinds of differences. Though it may be easy to slot them into the same category, there are many major differences when it comes to design and functions.

In the following section, we’ll walk through some of the things that they have in common and the differences that set them apart.


Below are the main differences:

Created to Handle Different Settings

Think about where you’ll be using a marine battery versus one made for a car. A car will generally be traveling on smooth, paved roads whereas a marine battery will be subjected to potentially rough seas and a lot of bumpy waters. Therefore, marine batteries tend to incorporate more structural enhancements to avoid cracks or other damage that can result from bumpy seas.

Power Capacities

The major difference you’ll see between a marine battery and a car battery are the power capabilities. Because a car battery’s main function is to start a car and provide a small amount of power to low-functioning features, there’s really no need for it to have sustainable power over time. In comparison, a marine battery is the main power source for several features within a boat, so it must reserve power to help those functions.

Internal Construction

Because marine batteries and car batteries are designed differently to perform different functions, the internal make-ups do differ slightly. In general, marine batteries have much thicker internal lead plates which allow them to provide a sustainable source of energy. They’ll also have larger, bulkier internal housings in order to protect them from bumpy seas, as aforementioned in the first bullet point.

MCA versus CCA

One of the other distinctions that sets marine batteries apart from car batteries is their “amp” ratings. Marine batteries use MCA, marine cranking amps, rather than CCA, cold-cranking amps, which is standard for automobiles. MCA is tested right at freezing point rather than below (which is used for CCA). This is because it is pretty unlikely that a pleasure boat will be heading out into subfreezing temperatures. 


Below are the main similarities:

Basic Functionalities

When it comes down to it, a battery is a battery. Regardless of whether it is a marine or a car battery, they provide the same basic function to the motorized vehicle they’re working for; power. One of the reasons it may feel tempting to stick a car battery on your boat is because of this commonality, but don't be fooled— although they both work as a reliable power source, boats and cars are fundamentally different and require different power capacities. 

Chemical and Structural Make-ups

Batteries are storage units for power. Whether they emit that power in a short burst or gradually over time, they have chemical and structural makeups that make that possible. Batteries are made up of two lead plates, an anode, cathode, lead oxide, and an electrolyte (either a gel or a liquid).


As you could probably glean from previous sections in this article, both car and marine batteries utilize similar designs. Gel or flooded batteries can be used in both automobiles and watercraft, as can dual-purpose batteries— it really depends on your vehicle and the functions you’re hoping to perform. 

Top Pick Between a Marine Battery and Car Battery

Now that you know the basic similarities and differences between marine and car batteries, we’ll walk through our favorite models in each category. The following products are batteries that have been tried and tested for effectiveness and come out on top in the eyes of reviewers. 

Best Marine Battery Overall:
Vmaxtanks Vmaxslr125 AGM Deep Cycle 12v

Vmaxtanks Vmaxslr125 AGM Deep Cycle 12v 125ah SLA rechargeable Battery for Use with Pv Solar Panels,Smart chargers wind Turbine and Inverters


  • Charges up quickly
  • Dependable performance
  • Battery life lasts a long time
  • Durable construction and design
  • Puts out a great amount of power


  • Some quality control issues
  • Loses battery capacity over time
  • Pretty heavy, not easy to transport

What Recent Buyers Report

Those who purchased this deep cycle marine battery were, for the main part, pleased with its performance and power output. Although it is very heavy, reviewers wrote that it had enough power to handle the many devices that come along with a watercraft. Buyers also appreciated the durable construction and design and the fact that it was consistently reliable. 

Why it Stands Out to Us

This battery earned the top spot on this list because it provides serious power and consistency that an angler can trust. Although it may take a bit of brute force to get it onto a boat, once in place, it does its job reliably well. 

Who Will Use This Most

This deep cycle battery is the perfect choice for watercraft-users who want a consistent power source with long battery life. While we wouldn’t suggest bringing this dense, heavy battery onto a dingy with a trolling motor, boats with a little more weight capacity should be able to handle this battery with ease. 

Bottom Line

Considering the only real issue with this marine battery is the weight, it is pretty clear that we have a winner on our hands. Providing a steady stream of power output and reliable performance over time, this deep cycle battery would be a great choice for any angler with a watercraft.

Odyssey 65-PC1750T Automotive and LTV Battery


  • No risk of spilling
  • Durable construction
  • Long-lasting battery power
  • Virtually no maintenance required
  • Very versatile in terms of performance


  • Very heavy
  • Pretty spendy
  • Doesn’t fit all cars, check before purchasing

What Recent Buyers Report

Car owners who purchased and reviewed the Odyssey battery were very enthusiastic about the product’s performance in their vehicles. Although this is an investment, buyers thought it was well worth the money due to its versatile power capacity, durable construction, and low-maintenance design. This is another battery that is on the heavier side of the scale, so be aware of that before purchasing.

Why it Stands Out to Us

We love that this car battery is versatile. Not only does it provide the sprint-like cranking power for starting up an engine, but it also functions similarly to a deep cycle battery, which provides a more “long-distance runner” power capability. This vehicle battery truly showcases the best of both worlds.

Who Will Use This Most

This high-powered battery would be a great fit for those driving a vehicle that needs quite a bit of power, like a truck. It’s reliable, consistent, and can handle the output that a bigger car or truck needs. But really, this is a pretty good fit for any car owner who doesn’t want to put a lot of maintenance time into their battery.

Bottom Line

Overall, the Odyssey battery is an awesome choice for car and truck owners alike. With the power capacity of a stallion and a great amount of versatility, this is an easy recommendation for any vehicle owner. 


Hopefully, this article gave you the tools and tips needed to understand the differences between marine and car batteries. Although they may perform similar functions, confusing the two can result in a major inconvenience for you. Knowing the similarities and differences can help you make an informed choice moving forward. 

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