Skip to content

⚡️Up to 80% OFF! --> Over 40% OFF for New Arrivals

Cart
0 items

ブログ

Using a Car Battery for a Trolling Motor Explained

by chenli fang 16 Jun 2025 0 Comments

In the world of small boats and fishing adventures, many users wonder: Can you use a Car Battery for your trolling motor? In this comprehensive guide, we’ll dive deep into the pros, cons, risks, and best practices of doing so. Using a Car Battery for a Trolling Motor might seem like an affordable and convenient option, but there are important factors to consider to avoid damaging your equipment or being stranded on the water. Read on as we explain everything you need to know about this topic.

battery operated camping heater

Why the Interest in Using a Car Battery for a Trolling Motor?

When boaters and anglers first look for a power source for their trolling motor, the Car Battery is an obvious candidate. Many already have spare Car Batteries or can access one at a lower cost than a deep-cycle marine battery.

The Convenience Factor

A Car Battery is easy to find and relatively cheap. Since most car owners replace their battery every few years, there’s often a used but still functioning Car Battery sitting around.

The Cost Advantage

Marine deep-cycle batteries can be expensive. In comparison, reusing a Car Battery for a trolling motor seems like a budget-friendly alternative.

The Curiosity of DIY Enthusiasts

Those who enjoy DIY solutions often experiment with using a Car Battery for a trolling motor, especially for short or light-duty trips.

Key Differences Between a Car Battery and a Deep-Cycle Battery

Before using a Car Battery for a trolling motor, it’s essential to understand how it differs from a proper marine battery.

Purpose and Design

Car Battery: Designed to provide a large burst of current for a short time (engine starting), then stay topped up via the alternator.

Deep-Cycle Battery: Built to provide a steady flow of current over a longer period, designed to be deeply discharged and recharged many times.

Internal Construction

A Car Battery has thin lead plates that maximize surface area for quick energy bursts. In contrast, a deep-cycle battery has thicker plates for long-duration power delivery.

Cycle Life

Car Battery: Tolerates shallow discharge but degrades rapidly if deeply discharged frequently.

Deep-Cycle Battery: Specifically engineered to handle deep discharges and longer cycle life.

>>See also Common Questions About Charging a 12 Volt Battery in a Prius

Can You Use a Car Battery for a Trolling Motor? Pros and Cons

Pros of Using a Car Battery for a Trolling Motor

Availability: Many people have access to a spare Car Battery.

Cost Savings: No need to invest in a new marine battery immediately.

Convenient for Short Trips: If your outing is brief and light on power consumption, a Car Battery can suffice.

Cons of Using a Car Battery for a Trolling Motor

Limited Battery Life: Using a Car Battery for this purpose will drastically shorten its life.

Risk of Being Stranded: A deeply discharged Car Battery may fail unexpectedly, leaving you stranded.

Not Designed for the Task: The discharge profile of a Car Battery is not suitable for trolling motors.

Potential Damage to Trolling Motor: Inconsistent voltage delivery can cause issues with motor performance.

Understanding Battery Ratings When Considering a Car Battery for a Trolling Motor

If you’re still considering using a Car Battery for your trolling motor, pay attention to the following battery ratings:

Cold Cranking Amps (CCA)

CCA indicates how well the Car Battery starts an engine in cold temperatures — irrelevant to trolling motor operation.

Reserve Capacity (RC)

RC shows how long the battery can deliver 25 amps before dropping below 10.5 volts. For trolling motors, higher RC is better.

Amp-Hour (Ah) Rating

Ah rating determines how long the battery can deliver a specific current. While Car Batteries generally have lower Ah ratings than deep-cycle batteries, this is the most relevant number for trolling motor use.

Best Practices When Using a Car Battery for a Trolling Motor

If you must use a Car Battery for a trolling motor, follow these best practices to minimize risk and extend battery life.

Limit Depth of Discharge

Try not to discharge the Car Battery below 50% state of charge. Use a battery monitor or voltmeter to track voltage.

Short Trips Only

Plan your outings to last no more than a couple of hours. The Car Battery simply isn't built for prolonged use in this application.

Frequent Recharging

Immediately recharge the Car Battery after use. Leaving it in a deeply discharged state will cause sulfation and permanent capacity loss.

Keep an Eye on Voltage

If your trolling motor starts losing power or the battery voltage drops below 11 volts under load, stop using it to avoid permanent damage.

When Using a Car Battery for a Trolling Motor Makes Sense

Occasional Use

If you use a trolling motor infrequently and for short trips, a Car Battery can be a temporary solution.

Testing or Backup

A Car Battery works fine as a temporary backup or when testing your trolling motor setup.

Budget Constraints

When funds are limited, and you're just getting started, using an available Car Battery is better than not going boating at all—just know its limitations.

When You Should Not Use a Car Battery for a Trolling Motor

Long Fishing Trips

Avoid using a Car Battery if you plan to spend all day on the water.

High-Power Trolling Motors

If your trolling motor is rated for 55 lbs thrust or higher, it will draw too much current for a Car Battery to handle effectively.

Remote Locations

Don’t rely on a Car Battery when boating in remote areas where a battery failure could leave you stranded.

Choosing the Right Car Battery for a Trolling Motor If You Must

If you decide to use a Car Battery, choose wisely:

Prefer higher capacity Car Batteries (higher RC and Ah ratings).

Use newer batteries in good condition.

Avoid old or worn-out Car Batteries with degraded performance.

How to Transition from a Car Battery to a Proper Marine Battery

While a Car Battery can get you started, moving to a deep-cycle marine battery is the best long-term solution.

Benefits of Deep-Cycle Marine Batteries

Designed for trolling motor loads.

Longer lifespan under deep-discharge conditions.

Consistent performance across entire charge cycle.

Recommended Battery Types

AGM (Absorbent Glass Mat) batteries: Maintenance-free, long-lasting.

Lithium Iron Phosphate (LiFePO4): Lightweight, very long cycle life (best for serious users).

Tips for Upgrading

Evaluate your typical usage pattern and select an appropriate Ah rating.

Invest in a smart charger suitable for your new battery type.

Properly dispose of your old Car Battery through a recycling program.

>>See also Complete Guide to Hoverboard Lithium Batteries One Stop Solution

Maintaining a Car Battery Used for a Trolling Motor

If you continue to use a Car Battery, proper maintenance is critical.

Regular Charging

Always charge the Car Battery fully after each use.

Voltage Monitoring

Monitor battery voltage before, during, and after outings.

Cleaning and Inspection

Regularly clean the battery terminals and check for signs of corrosion or swelling.

Storage

Store the Car Battery in a cool, dry place and keep it fully charged when not in use.

Final Thoughts on Using a Car Battery for a Trolling Motor

In conclusion, using a Car Battery for a trolling motor is possible, but it comes with trade-offs and risks. A Car Battery is not the ideal power source for trolling motors, and you should use it only for short trips, occasional outings, or as a backup.

If you want reliable performance and longer trips, investing in a proper deep-cycle marine battery is the smart choice. However, for those just starting out or experimenting, a well-maintained Car Battery can help you get on the water without breaking the bank.

Is a Car Battery Right for Your Trolling Motor?

Using a Car Battery for a trolling motor is a viable short-term solution with clear limitations. Understand the risks, follow best practices, and consider upgrading to a deep-cycle battery as soon as your budget allows. Whether you’re fishing in calm waters or testing your boat, always prioritize safety and battery maintenance to avoid problems on the water.

In your journey to power your trolling motor effectively, remember that while a Car Battery can work, the right battery can transform your boating experience.

battery operated camping heater
Prev Post
Next Post

Leave a comment

All blog comments are checked prior to publishing

Someone recently bought a
[time] ago, from [location]

Thanks for subscribing!

This email has been registered!

Shop the look

Choose Options

Recently Viewed

Edit Option
Back In Stock Notification
Compare
Product SKURatingDescription Collection Availability Product Type Other Details
this is just a warning
Login
Shopping Cart
0 items

Before you leave...

Take 20% off your first order

20% off

Enter the code below at checkout to get 20% off your first order

CODESALE20

Continue Shopping