ePropulsion electric outboard, EFOY methanol fuel cell hook up

Electric boat motor manufacturer ePropulsion and methanol fuel cell company EFOY announced at Germany’s Interboot boat show that they are cooperating on a system where the fuel cell can be used to extend the range of the motor.

EFOY is the brand name of consumer fuel cell products from SFC Energy, which also makes fuel cells for defense and industrial customers as well as things like special coils and transformers for electron microscopes.

ePropulsion is one of the world’s leading manufacturers of electric outboards and pod motors. The announced electric motor / fuel cell initiative is specifically for use with their Spirit 1.0 PLUS  outboard.

Methanol fuel cell acts as generator in hybrid system

The general concept is no different than an electric hybrid boat where a diesel generator is used  to ‘top up’ the charge in the batteries when required. In this case, though, the electricity is generated not by burning diesel fuel, but through a chemical reaction between a cartridge of methanol and oxygen from the air.

The EFOY brand was first introduced in 2010 with their  ‘Comfort’ series for use in things like RVs, campers, boats and as auxiliary power sources or generators for cabins and other remote buildings. They currently have a hybrid system with fuel cells and their own lithium-ion batteries, but it appears this is the first time they have worked with someone else’s batteries.

When ePropulsion’s Spirit 1.0 PLUS was introduced earlier this year, the big difference between it and the earlier Spirit 1.0 (no PLUS) was a new 48V battery replacing the previous  40.7V unit. Since 48 is a much more common battery voltage than 40.7, it would make sense that the PLUS is more compatible with the EFOY system.

Presumably the thing that needs to be coordinated with ePropulsion is getting the fuel cell and battery to communicate with each other so the fuel cell knows when to supply energy and when it doesn’t need to.

How a methanol fuel cell works

This is all good stuff, but what exactly is a methanol fuel cell, and how will it work with an electric boat motor?

The EFOY cell uses Direct Methanol Fuel Cell technology. It works somewhat similarly to a battery in that there are two electrodes – a positive cathode and a negative anode – and these facilitate the chemical reaction that generates the electricity. Remember, though, that a fuel cell generates electricity and a battery stores it.

Methanol, also known as methyl alcohol or occasionally ‘wood’ alcohol, has the chemical makeup CH₃OH: four parts hydrogen, one part oxygen and one part carbon. A sealed cartridge of  methanol is inserted in the fuel cell, the fuel cell draws oxygen from the air, the reaction is initiated and the output is electricity, some waste heat, and water vapour with what EFOY describes as ‘a little’ carbon dioxide. So while it is not entirely a zero emission generator, it is a lot better than using a generator that burns gasoline/petrol and diesel fuel.

Now why would you want one attached to the battery of your electric boat motor? In a word, energy density, meaning how much energy can be packed into how much weight, or volume of a substance. If you’ve read any of the Plugboats articles about solid state batteries, you’ll know higher energy density (i.e. lower weight batteries) is important for electric boats.

Gasoline/petrol can hold about 13 times as much energy as a lithium ion battery in the same amount of weight or space, diesel about 14 times as much, and methanol is somewhere in between, about 7 or 8 times the density of li-ion. Another consideration for a boat is the size and weight of the actual generator/fuel cell. The EFOY 70w system weighs 6.9 kg • 15 lbs with dimensions of 448mm x 198mm x 275 mm • 18″ x 8″ x 11″ (not including methanol cartridge).

Provides another 300Wh during a 4 hour trip

When it comes to performance, the press release announcing the ePropulsion/EFOY cooperation says “If boaters are traveling at medium speed with 300 watt and the EFOY fuel cell feeds approximately 75 watts during a four-hour trip, an additional 300 Wh are available. In this way, the fuel cell range extender function will provide another hour of travel – an increase of 25 percent.”

It appears at this writing that the cooperation is in the initial stages, but both parties seem excited about the possibilities. Danny Tao, founder and CEO of ePropulsion said “We are very pleased about this cooperation with SFC Energy. Together we will resolutely grasp the opportunities with our innovative solution.” To which  Peter Podesser, CEO of SFC Energy AG, added “Everyone benefits: partners and sailors – but most of all the environment.”