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Can You Use a Marine Battery in a Car?

Sep 20, 2024

When your car battery dies, are you considering using a marine battery in your car? Many vehicle owners often wonder if marine batteries can serve as an alternative power source for their vehicles. But is this a viable solution?

In this article, we’ll explore whether using a marine battery in a car is practical, what differences exist between marine and car batteries, and the potential advantages and disadvantages of this option.

What Is a Marine Battery?

A marine battery is specifically designed for use on boats and watercraft. These batteries serve two primary functions:

  • Starting the boat’s engine.
  • Powering onboard electronics like lights, trolling motors, and other accessories.

Accordingly, they correspond to two common types of marine batteries with different purpose:

What Is a Car Battery?

Car batteries, on the other hand, are built to provide a strong initial surge of power to start the engine, and they rely on the alternator to recharge once the car is running. As a result, car batteries primarily function as starter batteries, occasionally supplying power to the vehicle's electrical components, such as brake lights, headlights, and the instrument panel.

Can a Marine Battery Be Used in a Car?

A marine battery can be used in a car, but there are some important considerations:

  1. Fitment: Marine batteries may come in different sizes and may not fit properly in the battery compartment of a standard car. It's important to ensure that the marine battery physically fit in your car’s battery compartment and connect properly to the terminals. Ensure the battery is the right size and securely fits the tray to prevent movement while driving.
  1. Cold Cranking Amps (CCA): The marine battery needs enough CCA to start your vehicle. CCA is a measure of how much power the battery can deliver at low temperatures. Most car engines require around 600-800 CCA, depending on engine size and weather conditions.
  1. Charging System Compatibility: Car charging systems are designed with specific voltage and amperage requirements in mind. Marine batteries might have different charging needs, and using them in cars could potentially cause issues with the vehicle's electrical system.

Key Differences Between Marine and Car Batteries

While a marine battery can be used in a car, there are significant differences in design and function that impact long-term performance.

1. Purpose

  • Car Batteries: Built to deliver quick, powerful bursts of energy for engine startup and are recharged by the alternator once the engine is running.
  • Marine Batteries: Designed to handle both starting and deep cycling. They can sustain power over time to run electronics but are not optimized for constant high-current demands like starting car engines frequently.

2. Longevity and Recovery

Marine batteries are not engineered to handle the high-frequency starts that cars require. Over time, they can wear out faster in a car due to:

  • Frequent High-Current Demands: Car batteries are built for short, strong bursts of power. Marine batteries, especially deep cycle ones, are designed for slow, steady power and may wear out faster in a car.
  • Inability to Recover from Deep Drains: If you leave your lights or electronics on in your car, a marine battery may not recover as efficiently as a car battery. Marine deep cycle batteries are more sensitive to deep drains and may fail sooner if constantly drained and recharged in a car setting.

3. Internal Design

Marine batteries typically have thicker plates than car batteries, which makes them better suited for deep discharges but not for frequent engine starts. Car batteries, on the other hand, are specifically designed with thinner plates to maximize the burst of energy needed for ignition. Their thinner plates result in a reduced ability to withstand extreme conditions compared to marine batteries.

Related Reading: Marine Battery vs. Car Battery

Pros and Cons of Using a Marine Battery in a Car

Pros:

  • Vibration Resistance: Marine batteries are built to withstand constant vibration, making them potentially durable for off-road vehicles or those driven on rough terrain.
  • Emergency Use: In a pinch, a marine battery can work if it fits and meets your car's CCA requirements.
  • Temporary Fix: If you have no other option, a marine battery can get you back on the road temporarily.

deep cycle marine battery

Redodo 12V 100Ah Trolling Motor Marine Battery

Cons:

  • Reduced Lifespan: Marine batteries may not last as long in a car due to the constant high-current demands.
  • Poor Recovery from Drain: Marine batteries, particularly deep cycle models, may not recover well if you accidentally leave car electronics on and fully drain the battery.
  • Not Optimized for Car Use: Marine batteries are built for slow discharges and may not handle frequent engine starts well over time.

Should You Use a Marine Battery in a Car?

If you’re in a bind and need a quick solution, a marine battery can start your car as long as it fits and has enough CCA. But is it a good idea for long-term use? Probably not. Marine batteries are not designed for the specific needs of a car engine. Over time, their performance may degrade faster due to the constant demands of starting the car and recovering from deep drains.

For long-term reliability and performance, a dedicated car battery is a better choice. Marine batteries are best reserved for their intended purpose—powering boats.

If you need a reliable marine battery for its intended purpose, consider Redodo Deep Cycle Marine Battery and 650CCA Marine Cranking Battery. The Redodo 12V 100Ah Deep Cycle Marine Battery is designed to provide steady power for extended use, perfect for trolling motors and onboard electronics, while the 12V 20A Marine Cranking Battery deliver the 650CCA high burst of energy needed to start boat engines efficiently. Both batteries use advanced LiFePO4 technology, offering long-lasting performance, safety features, and excellent durability. Choose Redodo for high-quality marine power solutions built to handle tough marine environments.

marine battery for trolling motor

Conclusion: Can You Use a Marine Battery in a Car?

You can use a marine battery in a car if the battery is suitable and has enough CCA to start your vehicle. However, this is not recommended to do. Because it is not designed for the high-frequency, high-current demands of automotive use, which means it may not last as long or recover well from a deep drain. While this is a useful short-term solution, a battery designed specifically for automotive use is a better choice for long-term reliability and performance.