Electric Boat Motor Setups with Battle Born Lithium-Ion Batteries

In comparison to conventional outboards, electric yacht motors and sailing motors require less maintenance and offer fewer distractions during your time on the water.

An electric motor offers an alternative that does not rely on fossil fuels and will allow your vessel to be entirely powered by renewable energy. Modern electric motors can provide the same speeds as a gas or diesel outboard without the smell of exhaust, disturbing engine noise, or unplanned mechanical issues.

Learn more by calling our support and tech team at (855) 292-2831 or reading below.

What Is an Electric Boat Motor?

There are several different types of electric boat motors. In general, an electric boat motor is a way of powering your boat that doesn’t rely on loud, expensive, and smelly fossil fuels. Most of the electric boat motors you’ll find on the market today are trolling motors. These are small electric motors that are designed for maneuverability at slow speeds.

There are also faster electric outboard boats intended for recreation and even some high-powered fully electric yachts. One of the most common electric motor applications is in sailboats for docking and powered maneuvers. Check out Battle Born ambassadors: Sailing Uma who operate a sailboat this way.

How Big of an Electric Motor Do I Need For My Boat?

The size of your electric motor will depend on what you are trying to accomplish. Trolling motors are designed for low-speed operation and maneuvering a boat. Trolling motors are measured in pounds of thrust and the general rule of thumb is 2lbs thrust for every 100lbs boat weight.

For sailboats and cruising boats, power is in horsepower and motor size is best determined by the motor manufacturer. In general, sizes range from 5Hp for a boat under 25 feet to 70Hp for a 50-foot sailboat.

Motors for speedboats are a relatively new market and are running much higher powers. Like electric cars, these boats usually need to be fully designed to take advantage of the electric motor from the ground up and retrofits are not easily available as of yet. But, we anticipate they will be very soon!

Suggested Reading: Lithium Technology Spurs Electric Boat Innovation ?

How Long Will an Electric Boat Motor Last?

You can calculate how long your electric motor will run by figuring out the amp or watt draw and comparing it to your battery size. Of course, the bigger the battery the further you can go. Consider a 12Hp motor that draws 5Kw (5000 watts) at full load. This is around 100 amps at 48V. Thus a 100Amp hour 48 volt battery will run this motor at full speed for 1 hour.

The range will greatly depend on the size of the boat. A 12Hp motor on an inflatable boat might do 20 miles per hour and go 20 miles while on a large sailboat you might only go 5 miles.

What Kind of Battery Do You Need for an Electric Boat?

We highly recommend lithium batteries for electric boat motors. Compared to older lead-acid technology like flooded cells or AGM, lithium provides much more power in a much smaller and lighter package. Lithium also has the advantage of not being degraded from high power draws and can recharge quickly and without damage. Other battery tech needs to fully recharge each time or battery damage will occur.

As for the size of the battery, you’ll need an electric outboard boat motor entirely depending on the motor’s voltage and amp draw needs. Trolling motors typically operate at voltages of 12V to 36V. Larger motors might operate at 48volts or even higher. The higher the voltage the lower the current for the same motor, so higher voltages equal smaller cables and more power.

Can I Use a Lithium Battery to Start My Boat?

Lithium batteries are designed to be discharged to almost full capacity and recharged thousands of times, but they’re not necessarily designed to be starting batteries. This is why we don’t recommend using your electric motor’s lithium battery to start your boat. You will have an easier time if you use a separate battery as a starter.

Can I Convert My Boat To An Electric?

Most mechanics or individuals with knowledge about motors can convert a boat with an internal combustion engine to an electric one. For example, Sailing Uma, a YouTube channel that follows a couple who travels the world in their electric sailboat, removed their non-working diesel engine and converted it to an electric one.

To convert to an electric engine, you’ll need a compatible electric motor and power bank. Many companies create electric engines, and you can even find some companies with engines that will recharge your batteries as you move through the water. Do your research to find the right one for your boat.

For your power bank, the best option is lithium batteries. They’re more efficient, and Battle Born lithium batteries charge five times faster than standard lead-acid batteries. So, whether you’re charging while docked, using a generator, or using your regenerative engine, your lithium batteries will require less time, fuel, and energy to recharge.

How Do I Choose a Lithium Battery for an Electric Motor?

First, you’ll need to identify the voltage of your motor (i.e., is it a 12V, 24V, or 36V system). Then, determine its amp draw. For 12V motors, the amp draw is usually equal to the pounds of thrust.

Finally, choose a battery with a greater continuous discharge rate than your motor’s amp draw. This prevents your motor from asking for more power than your battery can supply.

Are Lithium Batteries Worth It for an Electric Boat Motor?

Should you invest in lithium batteries for your electric boat motor? Without a doubt. Lithium batteries are energy-dense, maintenance-free, and take up less room than their lead-acid counterparts. Not to mention, they have longer lifespans and can handle frequent discharge cycles. Because of all these factors, they are truly the best marine batteries on the market. We wouldn’t power our electric motors with anything else!