Are there any good third-party battery alternatives for the ePropulsion outboards?

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Derek01

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I'm in the process of going fully electric on my boat. The ePropulsion X-Series looks good, but their OEM batteries are way over my budget. ePropulsion claims you have to use their batteries, but I'm looking for a workaround. Has anyone successfully paired these motors with a third-party LiFePO4 battery? Any brand recommendations would be greatly appreciated!
 
What is the voltage of their battery packs?
 
You need to reverse your thinking. All the complicated stuff is in the batteries, BMS, and controller. The motor and prop are the easy part. The question should be is there an aftermarket propulsor that will work with the battery-BMS-charger-controller system I am interested in. That is what you are buying when you buy an integrated system. It's not like with lead batteries.

With lead batteries, we basically have the original open-source commercial standards of 6V, 12V, 24V 36V and 48V options. Most everything within a voltage class is plug-and-play if correctly sized for power and operating location. If you are one of the companies on the bleeding edge of small marine LiFePO4 battery propulsions systems, you really want to make sure that that doesn't happen to your system any time soon. So you take an active roll in making sure it doesn't and it can't.

For instance, here is a link to Honda's NMEA parameter group code list. This is why you can monitor a Honda outboard with some other display. https://cdn.powerequipment.honda.com/marine/pdf/misc/nmea2000_pgn_list.pdf

See if you can get such a list from ePropulsion. NMEA's updated electric propulsion codes are basically for monitoring screens. They aren't intended to support plug-and-play interoperability among brands of motors, controllers, BMSs, chargers and batteries.
 
Thanks for your information. Do you know what brand of lithium battery can be used for these NMEA Outboard Motors?
 
philSweet said:
You need to reverse your thinking. All the complicated stuff is in the batteries, BMS, and controller. The motor and prop are the easy part. The question should be is there an aftermarket propulsor that will work with the battery-BMS-charger-controller system I am interested in. That is what you are buying when you buy an integrated system. It's not like with lead batteries.

With lead batteries, we basically have the original open-source commercial standards of 6V, 12V, 24V 36V and 48V options. Most everything within a voltage class is plug-and-play if correctly sized for power and operating location. If you are one of the companies on the bleeding edge of small marine LiFePO4 battery propulsions systems, you really want to make sure that that doesn't happen to your system any time soon. So you take an active roll in making sure it doesn't and it can't.

For instance, here is a link to Honda's NMEA parameter group code list. This is why you can monitor a Honda outboard with some other display. https://cdn.powerequipment.honda.com/marine/pdf/misc/nmea2000_pgn_list.pdf

See if you can get such a list from ePropulsion. NMEA's updated electric propulsion codes are basically for monitoring screens. They aren't intended to support plug-and-play interoperability among brands of motors, controllers, BMSs, chargers and batteries.
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Thanks for your information. Do you know what brand of lithium battery can be used for these NMEA Outboard Motors?
 
Derek it is not so much about brand with batteries, as specification. For example if a motor requires up to 50 amperes at 96 volts, then your battery needs to be able to supply that. How long it supplies this for equates to range, similar to fuel capacity with a diesel.

Also batteries can be connected in series to provide higher voltages, so 2 X 48v, 8 X 12V, etc, could be connected to run your motor at 96V until they run out of power.

The ePropulsion team have decided on a proprietary solution where for whatever reason they require their batteries to be used. There might be a thermistor feeding battery temps to the computer, or something equally trivial, to justify their horribly exorbitant battery pricing.

I think you've come in with the wrong questions, because of course any battery of adequate output will run their motor, but will probably void warranty if not approved

Having spent the majority of my life dealing with manufacturers of marine equipment, things are rarely as presented, and I am highly suspicious of why purchasers are being heavily coerced into using their batteries.

How about telling us what you have currently, what you hope to achieve after converting to electric propulsion (speed, range, etc), and how much you are prepared to drop into this particular hole in the water?

Somebody might be able to show you how to reach your goals without the expensive proprietary overhead.
 
Derek01 said:
The ePropulsion X-Series looks good, but their OEM batteries are way over my budget.
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Then I'm afraid you're in the wrong game. No manufacturer is going to offer you something significantly cheaper. Doing it yourself is possible, but in the best case scenario it's gonna cost you about half the OEM price, and you have to really know what you're doing to replicate all the features of the OEM offer.

That's the nature of electric propulsion, even if the electricity is free you have to pay for the fuel tank up front. Internal combustion is the other way around, the tank is free, but the gas isn't. The difference is that you can pay for the gas in installments as you use it, instead of buying 1500 gallons when you buy the engine.
 
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Rumars said:
That's the nature of electric propulsion, even if the electricity is free you have to pay for the fuel tank up front. Internal combustion is the other way around, the tank is free, but the gas isn't. The difference is that you can pay for the gas in installments as you use it, instead of buying 1500 gallons when you buy the engine.
Click to expand...

Now this statement is an excellent way of describing the main difference between electric and internal combustion propulsion, and easy for anybody to understand - thank you Rumars, I shall take note of it, and no doubt use it in the future (with credit to you).
 
Quality of batteries can vary greatly, despite whatever the warranties may be. Individual cells are not clones when manufactured, they are tested and graded with poor or low performance cells often used to make low price batteries, which don't last their advertised Cycles. How to collect on a 10 year warranty when and Company is no longer in existence, has changed name to avoid liabilities, or is unresponsive in Asia? Testing agencies have found huge differences at least in most small batteries which are made in Japan, which are generally better, -than those with a big price advantage made in China.
Electric power has an advantage in that generally it can be converted more easily and more efficiently to just about any other kind of energy. Also Electric Power allows for low-cost self-sufficiency. It's easy and Fairly reliable for someone to make with their own purchased simple devices utilizing solar, wind or other sources. Oil based energy sources make someone particularly vulnerable to outside forces because of the thousands of steps involved from Discovery, Drilling, refining and finally getting to the petrol. So I guess once someone has paid up front for say solar cells and batteries, the cost of electric energy is free. But I think that grid energy is underpriced and is in the process of skyrocketing, because of the unrelenting increase in demand. JMHO.
 
Have very limited experience with Li cells .
But this is not secret knowledge.
I have been using LiFePO4 for 15 years. Still working . Fridge couple of hours. Headway 15AH.
More practice and the Devil stops being scary.
These are high-energy batteries and you need to think a little more about them.
Marine applications require special safety solutions.
I remember this US boat with a transplanted Nissan leaf battery/engine.
I hope everything is O.K.
 
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