Boating and fishing are fun, but manually hauling your vessel with an anchor can be a real hassle.
Getting your watercraft off and on the trailer without damaging the boat or car can be difficult.
Luckily, there’s a solution.
Instead of using a crank handle and muscle power, electric winches are powered by a 12-volt battery and variable speed high gear ratios.
It has two primary functions: pulling the boat onto the trailer and floating it into the water.
There are a few reasons why an electric winch is useful:
- Larger and longer boats are nearly impossible to be manually winched
- Requires a lot of physical exertion
- Eliminates the risk of hull damage
- Lifts and lowers the boat much faster
With an electric winch, you can focus on fishing or relaxing at sea instead of stressing out about manually hauling your boat.
However, most people who learn about electric winches are unsure what battery to use to power the pulley system.
In this article, we’ll cover everything you need to know about using deep-cycle marine batteries for winches.
Table of Contents
What Kind of Battery Do I Need for a Winch?
A winch is similar to trolling motors in that it primarily uses a 12-volt motor. This means you’ll need a 12-volt battery to match the motor’s voltage.
When choosing your battery, you’ll need to consider the battery’s type and battery chemistry.
The battery types are deep-cycle , dual-purpose , and car batteries . Battery chemistry is how the chemical energy is converted into electrical energy.
You can use a lead-acid , AGM , or a lithium battery for your winch. However, when selecting your winch, there are several factors to consider.
Cold Cranking Amps – cold-cranking amps measure how well the battery performs in freezing cold climates. Look for a battery that has a 650 CCA or above.
Reserve Capacity – determines how long a fully charged battery can deliver constant energy, usually 25 amps. We recommend a battery with a reserve capacity of 60 minutes.
Amp Hours – this rating tells users how much amperage a battery can supply for one hour. We recommend an AH rating of at least 70.
Spill Protection – AGM and lithium batteries have spill protection characteristics. The battery holds the acid absorbed by a glass mat to prevent acid from leaking out of the battery.
Can You Use a Deep-Cycle Battery for a Winch?
Yes, you can use a deep-cycle battery for a winch.
Each battery type has its own pros and cons.
Deep-cycle batteries use densely packed active materials and are built with thicker battery plates, enabling the battery to provide sustained power with less current draw over time.
Thus, it can handle regular charging and discharge compared to car batteries.
Conversely, starter batteries used in cars can supply a lot of energy to start the engine but require the car alternator to recharge the battery continually.
Although they are great for winches, they can drain and hurt your car battery in the long run.
As a result, deep-cycle batteries are less affected by full discharges and have more charging cycles, meaning a longer life span.
Deep-cycle batteries work great as stand-alone batteries solely to operate the winch.
They can handle the heavy-duty work cycles that a winch demands on batteries. That’s because deep-cycle batteries can be drained and recharged frequently without significantly shortening the battery life.
How Long Can You Run a Winch on a Deep-Cycle Battery?
The length of time your deep-cycle battery will run a winch greatly varies based on the load you’re pulling, the winch size, and the battery itself.
However, there is a way to calculate the approximate run time.
The formula for the run time of the battery on a winch is as follows:
Duration of Pull = (A/W) x T
A – Battery Amp-hour rating
W – The amp draw for the winch
T – Research capacity of the battery
The amount of amps drawn for the winch depends on how much weight you’re pulling and the size of the winch. Here’s an example of amp-draw based on line pull:
| Line Pull (in lbs) | Amp Draw |
| 0 lbs | 71 amps |
| 2,000 lbs | 169 amps |
| 4,000 lbs | 248 amps |
| 6,000 lbs | 328 amps |
| 8,000 lbs | 413 amps |
| 9,000 lbs | 482 amps |
Let’s say you’re looking to pull a pontoon boat that weighs 6,000 pounds. Your battery AH rating is 120, the amp draw is 328, and the reserve capacity of your battery is 60 minutes.
Time of Pull = (120/328) x 60 = 21.95 minutes
In this example, your deep-cycle battery has a run time of nearly 22 minutes.
How to Run a Winch on a Deep-Cycle Battery?
Wiring a winch with a deep-cycle battery is simple once you know the steps.
- Mount the deep-cycle battery to a secure spot in the back of the truck or trailer. Ideally, place the battery inside a battery box or toolbox
- Connect the positive wire to the positive post on the electric winch.
- Attach the negative wire to the negative ground post.
- Run both positive and negative wires from the winch to the battery compartment.
- If the winch comes with a circuit breaker , it needs to be installed in line with the power wire that runs to the deep-cycle battery
- The deep-cycle battery will need to be recharged periodically with a battery charger to continue pulling.
- From there, you can use the remote to turn on and activate the electric winch.
FAQs
Here is a common question people ask when using a marine battery for a winch.
What Size Battery Do I Need to Run a 12,000 lb Winch?
The size of the battery will depend on the electric winch model.
Most 12,000 pound winches require a battery with at least 650 cold-cranking amps (CCA), giving it sufficient power to operate a heavier winch.
For a 12,000 pound winch, a group size 31 or 48 battery is a great size for winching.
However, you’ll want to check the winch manual to see the recommended size and battery rating needed to power a 12,000 lb winch.
Conclusion
Marine deep-cycle batteries work great for electric winches, especially because they can supply consistent power and last a long time.
Make sure to look for batteries with an AGM or spill-proof design, a high AH rating, high CCA, and the right battery size.
Now you’re ready to hook up your winch and head to the waters!
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