Electric Motor

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.

Our Battle Born lithium batteries work amazing in an electric motor application while offering similar benefits. Battle Born Batteries require no maintenance or venting while offering two to three times more power, and weigh in at a fraction of lead-acid or AGM options. We offer batteries that will prove to be reliable enough to sail away with the power needed for water getaways, big or small. Go clean, green, and quiet with Battle Born.

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.

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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 ?

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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.

electric boat motor battery


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.

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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!

Are you thinking of making the switch to lithium batteries for your electric boat motor? Do you have any questions about lithium batteries and electric boat motors? Give us a call today at (855) 292-2831.

Why choose Battle Born?

Last 10 Times Longer than Lead Acid

Even after 3000 – 5000 life cycles Battle Born Batteries retain 75 – 80% of their original capacity. For most users, it will take 10 to 15 years to reach this amount of life cycles.

2 to 3 times more power

Our batteries will supply you with two to three times the power in the same physical space of a lead acid battery.

Charge 5 Times Faster

With a high charge rate of half of your total bank and short absorption times, your batteries will charge in a fraction of the time of a lead acid. This faster charge rate allows you to use your generator less which means less fuel consumption, less noise, and less pollution.

High Discharging Capabilities

Our 100 Ah batteries provide a continuous 100 amps of power, surge of up to 200 amps for 30 seconds and even higher loads for a ½ second.

Efficient and High Performance

Our batteries have virtually no internal resistance and will not heat up or swell when charging or discharging. We also have a real power rating so whether you’re using 1 amp for 100 hours or 100 amps for one hour, you will receive the full amount of power your batteries are rated for. With a very flat discharge curve, power remains much more consistent with Battle Born Batteries even at a low state of charge.

Environmentally Safe and Non-Toxic

One lead acid battery can contaminate acres of municipal waste, but Battle Born Batteries are not toxic and are made with the safest lithium chemistry on the market. This allows you to place them anywhere in your rig whether it’s under a bed, a dinette, or even a small enclosed area without the fear of our batteries “off gassing” like lead acid.


Our batteries are ½ to ⅔ the weight of a standard lead acid battery with more deliverable power.

Maintenance Free

Battle Born Batteries have a built-in management system to help protect you and your investment in the batteries in any strenuous situations such as high/low temperatures, high/low voltages, current surges, and short circuits. They also can be placed in your system with zero maintenance, so you no longer have to worry about adding water to your batteries or cleaning corroded terminals. Our batteries also have a very slow self-discharge rate so they can be left in storage for over a year without requiring you to hook them up to a trickle charger.

Customer Service 

We employ a team of USA-based experts at Battle Born Batteries to help with your customer service, sales and technical needs. Our industry-leading team utilizes clear communication via phone and email, along with product knowledge and problem-solving skills to assist with any questions you may have along the way. Whether you’re looking to upgrade your batteries, a complete power system or anything in between our team can provide the expertise needed to guide you through a lithium conversion. Feel free to contact our team at (855) 292-2831 or [email protected]. 

10-Year Warranty

We believe in our batteries and we want you to believe in them too. That’s why we ship every battery out with a 10-year warranty. If you have a problem, we want to fix it as quickly as possible so you can go on your next adventure!

Excellent Solar Systems

Battle Born Batteries allow you to take full advantage of solar by creating fast charging and fully sustainable power systems with a variety of applications.

Are my charging devices compatible with your batteries?

To determine whether your devices are compatible with BB batteries, take a look at the manual for each component and look at the specifications. If the specs in the manual match up with the Charging voltage: 14.2-14.6 V and the Float voltage: 13.6 V or lower, they are compatible with our batteries.  

If you can adjust settings (such as a custom profile) on your devices to various charging and float voltages, then simply change the settings to match ours.  

You are also more than welcome to give us a call at (855) 292-2831 or contact us at [email protected]. 

How do I know what size cables to use with my system?

When considering cable sizing there are a few factors to consider.

First, what is the size of the load you are powering with the battery bank?

Second, how far away from the battery is the load? You can do voltage drop calculations to see if you need to step up your cable size.  

Here is an easy reference chart: 
Wire Cable Guide
As a rule of thumb, you can use these numbers as a guideline.

-4 AWG wire approximate max rating is 157 amps DC
-1/0 AWT wire approximate max rating is 291 amps DC
-4/0 AWT wire approximate max rating is 456 amps DC

How do I protect against a high voltage spike back?

When current is flowing and abruptly stopped or interrupted, there is a potential for a high frequency voltage spike or pulse. Normally this voltage spike is an unwanted feature, as it tends to damage MOSFETs or other solid state switches and relay contacts.

Alternator Protection Device

An alternator protection device, also known as a snuffer, is meant to protect a vehicles alternator if a spike is created. This device gives the spike a route to safely discharge without risk of damaging the alternator.

Issues such as loose wires, blown fuses or a running engine switching off can be some common sources of a voltage spike. The alternator protection device is a costeffective way to protect a very expensive part of your vehicles charging system.  

Sterling Power makes a 12 and 24 volt alternator protection device that can be installed on all vessels utilizing an alternator as a primary charging source.

What type of inverter do I need?

Selecting an inverter can be confusing. The varying styles and qualities available in stores and on the internet don’t make it any wasier.

What does an inverter do?

One of the primary functions of an inverter is to take direct current (DC) power and invert it into 120 volts, for using appliances through a wall receptacle, or directly from the inverter.

Many all-in-one units allow a pass-through from shore power or genset, a high amperage DC charger and transfer switch.

What else should I consider?

We recommend inverters that have a “pure” or “true” sine wave as the “modified” or “square” wave inverters are harder on components. They also cause more heat and can lead to damage to sensitive electronics over longer periods of time.

Victron, Magnum, Xantrex, ProMariner and Mastervolt are some examples of high quality units that are used in many marine systems.

One of the most important things to consider is your maximum need in wattage at any given time. Take a look at the wattage specifications on your devices and consider which of these you will be using at the same time and add them together.

For example, If your power need is 1600 watts then round up to a 2000 watt inverter. When choosing an multi-function inverter, consider how much of a maximum charge you will require for your bank of batteries.

Upon request we will program your Victron inverter charger for the number of Battle Born batteries in your bank at no charge.  

Does my inverter need to be in a ventilated area, so it doesn't overheat?

Many inverter manufacturers recommend that you have some space around inverter sides and the top or bottom for air flow. This will allow the internal fans to circulate air within a compartment and properly cool your inverter when necessary. 

Please check your specific manufacturers recommendations and user manuals for further details.  

Do I need a shutoff switch for your batteries?

Battery switches or “master disconnect” switches are a common item in RV or marine systems. They are used to cut all power from a battery bank and the connected loads.

These devices are very versatile and can be used in any circuit when performing maintenance or an emergency shut down. Very often you will see placement of these switches between inverter(s) and a bank of batteries.

Below are some of the most common styles:

Single on/off

3 position – used to shut off or switch from one bank of batteries to a second

4 position – used to shut off, switch from one bank to a second or combine the two

Do I need a BIM or a battery to battery charger?

Battery Isolation Manager

The battery isolation manager (BIM) is typically used in motorized systems with 3 or more Battle Born Batteries. Lithium batteries tend to pull a lot of power off your alternator, which over time could cause it to overheat.

The BIM works on a duty cycle. It charges your house battery bank for 15 minutes, then taking 20 minutes to rest so your alternator can take a break and never has the opportunity to overheat. 

Battery to Battery Charger

Battery to battery chargers are typically used in applications where you have 1 or 2 Battle Born Batteries. This is because our batteries have a recommended 50 amp charge rate per battery. If your alternator is applying a higher amperage to your batteries than the recommended charge rate, you will need to limit the amperage.

The battery to battery charger will limit the amperage coming off your alternator and will apply a safe charge to your batteries. 

Both devices will properly isolate your lithium batteries from your starting battery. 

How many solar panels do I need to charge my batteries?

Answering this question can depend on the amount of space you have on your vehicle and how fast you want your bank to charge. 

As a general guideline we recommend 200 to 250 watts of solar per 100 amp-hours of battery. This will give you the ability to charge from nearly empty to full in a six to eight-hour time frame.

Many factors can change this calculation and you are invited to call at (855) 292-2831 or email us at [email protected] if you would like to discuss in greater detail.  

What size of Victron solar charge controller do I need?

Many RVer’s run into trouble in deciding which solar charge controller to choose and there are many specific models with different voltage and amperage ratings.  Which one is right for your application?   

Victron’s standard “Blue Solar” model is a set and forget controller without readouts or internal Bluetooth.  If you would like a Bluetooth version with all viewable information via the “Victron Connect” application from your mobile device, then the “Smart Solar” version is your best choice.   

Second, decide how many watts of panels you want in your solar array and take a look at our compatibility table to determine the product that best fits your system, here.  

Upon request we will program your Victron solar charge controller for the number of Battle Born Batteries in your bank at no charge.   

Are your batteries waterproof?

Battle Born Batteries are sealed and can handle being in a moist environment. Our batteries, just like any electric device, should not be submerged in water.

Upon request and as an upgrade to our standard battery, we will add a waterproof seal, giving added protection from moisture and more extreme marine environments.

How much do your batteries weigh?

Battle Born Batteries are 1/5th the weight of a traditional lead acid battery when matching the same usable capacity. This can result in a significant reduction in gross vehicle weight, not to mention being easier to load, install or move if necessary.

BB10012 and BBGC2 (12 volt 100 Ah) – 31 pounds

BB5012 (12 volt 50 Ah) – 17 pounds

BB5024 (24 volt 50 Ah) – 31 pounds

How do I size a li-ion battery bank for my system?

Sizing a battery bank for an off-grid or mobile power system can get complicated if you don’t have all the information you need to make the right calculations. You will need some basic information to get started.  

You will need the maximum and continuous draw – in amps or watts – of the devices you want to power. These are usually found somewhere on the device on a sticker or plate that shows the amps and volts of that device or the power in watts. 

As an example, let’s just say that our system needs to run 10 amps at 120 volts for 3.5 hours.  

10 amps x 120 volts = 1200 watts of power.  

1200 watts x 3.5 hours = 4200 watt-hours of energy.  

Next you need to convert 4200 watts-hours to direct current (DC) amp-hours. For our example, we will use a 12 volt battery bank.  

4200 watts-hours / 12 volts = 350 DC amp-hours of battery energy needed for our sample application.  

Also, the battery needs to be able to deliver 1200 watts/ 12 volts = 100 amps of power.  

We will use the 100 amp-hour Battle Born battery to build this system.  

350 amp-hours / 100 amp-hours = 3.5  

We would need to use four 100 amp-hour LiFePO4 Battle Born Batteries to power this system. 

Can I charge my batteries using the alternator?

Very often the alternator will charge lithium batteries at the proper voltage (14.2 to 14.6 V), but we recommend not to exceed a 50% charge rate, this means a max of 50 amps for each 100 Ah battery.

An example would be a high 220 amp alternator putting out its full charge to the electrical system. An alternator charging the starter battery, running the electronics in the vehicle, and if wired with thick enough cables, might have around 150 amps leftover to charge your Battle Born Batteries. In this instance, three of our batteries would be a good match for the alternator’s charge. 

Some things to consider when connecting a starter (lead acid) battery to a lithium battery bank:

  • 2 lithium batteries or less, you will probably want to use a battery to battery charger such as the Sterling product on our website:
  • Higher amp units charge the batteries faster. These devices will not only regulate the charging current but also replace your existing isolator.
  • For 3 or more lithium batteries connected to a starter battery we recommend our Li-BIM.

These are generalities, but if you give us the amperage of your alternator, the model of your isolator, and how many lithium batteries you are planning to use, we can give you a better suggestion as to what you may need. Call us at (855) 292-2831 or contact us at [email protected]. 


Are there any temperature restrictions on Battle Born Batteries?

Battle Born Batteries protect themselves from charging in cold temperatures and won’t accept a charge once the internal cell temperature drops to 24°F. At this point they will continue to discharge even down to -4°F. At this temperature we recommend no longer pulling power to avoid damaging the batteries.

Insulated battery boxes, heating blankets, and placing your battery bank inside your RV will help keep the temperature stable. On the high end of temperature range, the batteries will shut down once 135°F is reached.

Do I need to install all of my batteries at the same time, or can I add additional batteries later?

Lead acid battery manufacturers will state: “do not mix old and new batteries. Doing so will reduce overall performance and may cause battery leakage or rupture.” They also recommend replacing all batteries within a bank at the same time.

A partially used lead acid battery will drain energy from a new one, reducing the total amount of battery power available.

This is not the case with Battle Born LiFePO4 batteries. You can add new batteries to your original Battle Born bank up to two years down the road without damaging, reducing lifespan, or harming them in any way. 

When docking for an extended period of time, what do I need to do to protect my batteries?

The best way to store our batteries for an extended period is to fully charge them and then disconnect them from everything. Removing the negative lead from the battery bank is also recommended. 

The batteries do not need a trickle charge or maintenance while stored. They will only lose around 2 – 3% of their charge per month. If possible, we recommend storing them in a temperature above freezing.  

Storing batteries in subzero weather (-15°F or lower) has the potential to crack the ABS plastic and could lead to a greater loss in charge. In some cases they can lose much more than the expected 3% monthly loss.  

If you are storing your entire system, we recommend the use of a  battery guardian, which will help protect your batteries by disconnecting them from parasitic loads once they reach a voltage of 11.5 V. 

Can I use your batteries in cold cranking applications?

Our battery is designed as a deep cycle storage battery and doesn’t offer the cold cranking amps most applications require for starting.

Multiple batteries connected in parallel can be used in an emergency situation, but prolonged use in starting applications can result in diminished capacity or damage to the battery’s management system. 

The continuous discharge rate of our batteries is 100 amps, 200 amps for 30 seconds and higher loads for ½ second. Cold cranking applications typically exceed 200 amps which will cause our batteries to shut off.

What is the maximum amperage I can charge my batteries at?

Our batteries allow a charge rate of 50 amps for each 100 Ah battery. For more than one battery, you can simply take the entire Ah of the bank and cut the number in half.

For example, three 100 Ah Battle Born Batteries total 300 Ah. Cut this number in half and you have your maximum recommended charge rate of 150 amps. 

What does "drop-in replacement" actually mean?

Our batteries are drop-in replacements for typical lead acid batteries. This means that our batteries are designed to fit like a normal Group 27, 31 and GC2 battery in your bank.

This, however, does not mean our batteries are plug and play. Our batteries still may require specific components and programming to run your application.

To figure out if your components will work with our batteries, give us a call at (855) 292-2831 or send us an email at [email protected].

How long do Battle Born Batteries last?

As an update to this video, our batteries come with a 10-year warranty (8-year full replacement manufacturer’s defect warranty and 2 years prorated).

They are designed to last 3000 – 5000 cycles, at which point the battery will still hold 75 to 80% of its energy capacity.

Are your batteries designed to handle vibration?

Our batteries are assembled and constructed with the highest quality components available. They are designed to withstand vibration and keep working for thousands of cycles.

You will need to check your connections from time to time (as with any kind of battery) to make sure they maintain good contact from cable to battery. 

Why is my battery registering a voltage between 0-5 volts?

If your battery registers between 0 to 5 volts this means that its in low voltage disconnect mode. This happens if the battery has been drained of capacity and is protecting itself from further discharge.

At this point you will need to apply a direct 12 V source such as the alternator via the starter battery or by connecting it to your starter battery with jumper cables until you see the voltage reaches 10-10.5 V.

Some inverter chargers will also bring the batteries out of low voltage disconnect. 

Check out our Customer’s Systems!

About Sailing Uma

Sailing Uma consists of Dan and Kika, two architects who wanted to sail the world and experience plenty of adventures! Their boat “Uma” is a 1972 Pearson 36 that has an electric motor. They chose an electric motor was because it best fit their sailing style.

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About Learning the Lines

Randi and Jordan from Learning The Lines have a 1978 Endeavour 32′ Sailboat named SV Freebie. This 100% electric cruiser is powered by the sun via 600W of solar.  They chose an electric motor was because they wanted to have zero fossil fuels aboard.

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