Marine Battery vs. Car Battery: Key Differences You Need to Know

When shopping for a battery for your boat, you might be confused between marine battery and car battery. It's natural to consider the readily available and often cheaper automotive power units, but understanding the distinct differences between these two types of batteries is crucial. It can significantly impact the performance and safety of your vehicle, whether it's on the road or the water.

In this blog post, let's dive into why marine and car batteries are in two different sections of the store and what makes each one unique.

How Are Boat and Car Batteries Different?

When you browse online shopping stores and offline supermarkets looking for batteries, you may find that marine batteries and car batteries look similar, but they are designed for different purposes and have distinct differences. Here is the brief of their differences:

Automotive Batteries:

• Purpose: Primarily designed to deliver a quick burst of high power to start the engine.
• Lead Plates: Contains more, thinner lead plates for a higher discharge current.
• Design: Optimized for brief, high-energy output followed by recharging from the alternator.

Marine Batteries:

• Purpose: Built for dual functions—starting the engine and powering onboard electronics.
• Lead Plates: Equipped with thicker, sturdier lead plates for prolonged energy discharge.
• Vibration Resistance: Designed to withstand vibrations and shocks common in marine environments.
• Terminals: Feature specialized terminals suitable for marine applications.
• Types: Available in various forms—Starting or Cranking, Deep Cycle, and Dual Purpose (Starting and Deep Cycle) Battery.

The Full Comparison of Marine Battery vs. Car Battery

1. Purpose

The primary difference between marine batteries and car batteries lies in their intended use. Car batteries are designed to provide a high burst of amperage to start the vehicle's engine and power the electrical systems while the engine is running. Once the engine is running, the alternator takes over, keeping the battery charged and powering the vehicle's electrical systems.

Marine batteries, on the other hand, are required to perform a broader range of tasks. They not only need to start the engine but also provide power for various onboard electronics such as lights, pumps, GPS systems, and fish finders. This means they must be capable of sustaining power delivery over extended periods without being recharged as frequently as car batteries. The ability to handle these diverse tasks makes marine batteries indispensable for boat owners.

2. Construction

The internal construction of a car battery includes more, thinner lead plates, which maximize surface area to allow a higher discharge current. This design is ideal for delivering the quick burst of energy needed to crank the engine but is not suited for deep discharges or sustained power delivery.

Marine batteries are built with thicker and more robust lead plates to endure the constant vibrations and harsh conditions found in marine environments. The thicker plates also allow marine batteries to discharge energy over a longer period, making them better suited for continuous use. Additionally, they are also designed to resist the effects of constant motion, vibration, and rough sea conditions.

3. Capacity

Marine batteries are designed to have a higher amp-hour (Ah) capacity compared to car batteries. This allows them to provide a steady stream of power over an extended period, making them suitable for powering various electrical equipment on a boat. Car batteries, on the other hand, have a lower amp-hour capacity since they are primarily used for short bursts of high-power output to start the vehicle's engine.

4. Maintenance

Marine batteries often require more regular maintenance due to the harsh conditions they are exposed to, such as frequent charging and discharging cycles, as well as exposure to moisture and saltwater. Car batteries, while still requiring maintenance, are not subjected to the same level of wear and tear as marine batteries. This makes the durability and safety of marine batteries more demanding.

5. Starting vs. Deep Cycle

Car batteries are typically designed as starting batteries, which means they are optimized to deliver a quick burst of energy to start the engine. They are not intended for deep discharge cycles. In contrast, marine batteries are often used to deep cycle, meaning they are designed to withstand regular deep discharges and recharges without affecting their performance or lifespan. This makes them ideal for powering multiple electrical devices on a boat over an extended period. Additionally, marine batteries also including starting batteries and dual-purpose batteries.

• Deep Cycle Batteries: Designed to provide a steady amount of power over a longer period, ideal for running electronics and trolling motors. Redodo Group 24 Deep Cycle Battery and Group 31 Battery are ideal options, they can also be used in RVs and home energy storage.
• Starting Batteries: Provide the initial burst of power needed to start the boat's engine. Redodo Marine Cranking Battery provides unmatched cranking power for fuel-powered outboard motors up to 135hp.
• Dual-Purpose Batteries: A hybrid that offers both cranking power and the ability to handle deep discharges, suitable for boats with limited space. The Redodo Dual-Purpose Marine Battery is engineered to deliver reliable cranking power and sustained deep-cycle performance for all your boating needs. 

MCA vs. CCA Ratings of Marine Battery

One of the key identifiers of a marine battery is its Marine Cranking Amps (MCA) rating, as opposed to the Cold Cranking Amps (CCA) rating used for car batteries.

Cold Cranking Amps (CCA)

CCA measures the battery's ability to start an engine in cold temperatures (0°F/-18°C). This is crucial for car batteries, especially in colder climates where a high CCA rating ensures reliable engine starts in freezing conditions.

Marine Cranking Amps (MCA)

MCA is measured at 32°F (0°C), a temperature more typical of marine environments. Since boats are rarely used in sub-zero conditions, MCA provides a more relevant measure of a marine battery's starting power. It's important to note that while MCA ratings are higher than CCA for the same battery, they are not directly comparable due to the different testing conditions.

Redodo 12V 140Ah Dual Purpose Marine Battery delivers an impressive 900 CCA and 1200 MCA, providing unbeatable cranking power and dependable deep-cycle performance.

Is Marine Battery Better Than Car Battery?

Marine batteries aren't inherently better or worse than car batteries, they are designed for different applications and built accordingly. When consider choosing a battery for your boat, there is no doubt that Marine batteries are the best choice. Using a marine battery in your boat is essential for safety, reliability, and performance. Marine batteries are built to withstand the unique challenges of the marine environment, providing the necessary power for both starting the engine and running onboard electronics. By choosing the right marine battery, you ensure that your boat is ready for any adventure on the water, all season long.

Can I Use a Car Battery in a Boat?

While it might be tempting to cut costs and use a flooded automotive battery to start your boat, it's not advisable. Automotive batteries are not built to withstand the tough conditions that boats face, and they would not be a smart choice, likely leading to more frequent battery replacements.

The most crucial factor to consider when buying a new battery for your boat is whether it meets your boat's requirements. Marine batteries are available in various designs to cater to your boat's needs and are specifically engineered to handle the challenging marine environments, making them the obvious choice for a replacement battery.

Learn More: Marine Battery Group Size Chart & Guide

Conclusion

In conclusion, while marine batteries and car batteries may appear similar at first glance, their differences in construction, purpose, capacity, and maintenance make them distinct from each other. It is essential to consider these variations when choosing a battery for your specific needs, whether it be for your vehicle or marine vessel. By understanding these variations, you can select the right battery that will effectively meet the power demands of your car or boat, ensuring optimal performance and longevity.

Explore Redodo Lithium Marine Battery now to ensure your boat is equipped with reliable, long-lasting power! If you have any questions about selecting the right battery for your boat, feel free to contact us by service@redodopower.com.