The Epropulsion Spirit XS - A Horse for our Course?

[Graham W]

Here's what Torqeedo says:
"Risk of death from lithium fire!
Death or severe physical injuries may result.
■ A lithium fire cannot be extinguished using water; if possible, smother the fire with sand.
■ Use water to cool the battery and to prevent the fire from spreading.
■ Move the battery to a position in which it causes the least amount of dam-
age possible."

There are also warnings about explosions due to formation of oxyhydrogen gas (after being submerged), fatal electric shocks and even death from electromagnetic radiation (avoid the kill switch if you have a cardiac pacemaker).

The ePropulsion manual doesn't use the word fire once, as far as I can see. And there are very few risk warnings compared to Torqeedo, presumably because the latter is owned by a large corporation with an impressive legal department. ePropulsion does however have one instruction that we should all take to heart "Do not leave the outboard in the water while the boat speed reach 35km/h."

[Sea Simon]

Interesting, thanks!

At any sailing competition/event SI's NOR etc usually stipulate that i need an appropriate fire extinguisher, due to my petrol outboard. Sometimes a fire blanket too?

I think i will have to propose that battery powered craft  also carry appropriate means to extinguish?
A couple of large buckets of wet sand ought to do the trick.....
Both to make the batteries safe, and negate any weight reduction advantage! ?

In my current world, work and domestic, (pun intended) the only interaction I have with energy dense batteries is the new range of 36v portable tools. Very impressive capabilities, but he 'elf n safety crowd don't seem to have caught up with the tech yet?

[MarkDarley]

Simon,
Nestaway tells me that the Eprop battery floats, is entirely submersible and waterproof. If it goes in the water you just rinse with fresh and plug it back in.  That is not the case with their remote batteries.
I especially asked as I was interested in carrying an extra battery in our flooding lockers which are part of the righting action for the BR.  They said, absolutely no problem.
Mark

[Peter Cockerton]

Epropulsion UK called me the other day after I left some feedback on one of their questionnaires regarding a 3 bladed prop option for the Spirit 1. They are not currently looking to develop this option but may look at it in the future along with a new design of engine better suited to the outboard wells used on a number of the Swallow Yacht designs, it should be available mid 2021 (some conversations with SY I believe have taken place on other matters as well)

He is however looking at modifying an existing 3 bladed prop from a 3rd party supplier and has ordered one himself to understand the changes and kit required to possibly offer us a solution. The prop shaft on the Spirit 1 is only 10mm and on the plastic props I have looked at they fit a 12mm shaft, also the shaft is quite short and again the prop I have ordered and tried to modify required the front and back of the prop to be cut down to get sufficient shaft through the prop to attach the locking nut (I am still waiting though for the prop which is suggested on the forum post to arrive from Amazon.

Peter C

[Graham W]

Interesting stuff.  Matt has tried to incorporate Torqeedo gear into his boats in the past and been unimpressed with the results.  He even said several years ago that if he wasn't designing boats, he'd be designing electric motors to take on Torqeedo.  So the fact that he's talking to ePropulsion (and that they're looking at a 3-blade idea) tells you that they're a lot more responsive to ideas and to their customers.

Torqeedo's batteries are supposed to be waterproof too, so the oxyhydrogen explosion risk is a puzzle.  Unlike ePropulsion's, they definitely don't float.

[Graham W]

I'm going to wait for the next version of the Plus battery before deciding whether I need a spare.  The speed with which eProp introduce new products probably means that we won't have to wait too long for an even higher capacity version.  I don't expect that they'll change again from 48V as it fits with too many other things that they're doing.

[Graham W]

Here's a question for those of you proposing to keep your Spirit battery somewhere other than on top of the motor:  given the size of the power cable terminations, how are you threading them through any bulkheads that you encounter and how are you sealing the resulting hole(s) up afterwards?  I can't see any possibility of dismantling anything at either end of the power cable to pass it through a smaller diameter bulkhead hole; and the same issue faces any cable gland that you use to seal the hole up afterwards.

[Sea Simon]

Sorry, I don't mean to keep banging on about it, but..

Never having seen one of these Epropulsion floating batteries, I'm trying to understand how they prevent a dead short across exposed terminals, say when in a locker, or immersed in sea water?

We have had issues with 36v LiIon power tool batteries left out in the rain, never mind floating!

GW. Take it the warning  "Do not leave the outboard in the water while the boat speed reach 35km/h." hasn't been an issue....so far!?!

[Graham W]

Simon,

The battery has close-fitting dust caps on its sockets that may save it from the worst effects of a dunking.  However, I'm not volunteering to find out.

Ian at Nestaway has confirmed that the solar controller for the Spirit Plus will arrive in early September.  Also, after consulting with the eProp technical bods, he confirmed that I can safely route a charge from my two 26V electric bike batteries through the solar controller.  In the absence of sunshine, this will nearly double the eProp's range, saving me from having to fork out another £800 for a spare battery.

[david]

Hi, I have not seen one of these motors. I did find a video where it is used on a tender. So, if there is anyone else out there, like I was, is wondering,  what this is all about take a look. As they use the motor, you can see how they handle moving it about on their mother boat. Skip to 3.50 to see the motor. (Not that I am a fan of these videos, the hosts can be tiresome. But I did find it informative to see the motor in action).

https://www.youtube.com/watch?v=Fi0S6r7T2wE

[Graham W]

For full exposure to eProp's US marketing department, see this one https://www.youtube.com/watch?v=ns6fSqH3xG0.  The drone shots show somewhere with beautiful clear water - Florida?

[Sea Simon]

Thanks for the video references, very helpful.

I see the battery floating, and the battery/motor power cord......with plastic plug/socket. Guess that's the key?
Rather like the Panasonic Tough Book PCs. I recall a LOT of little rubber bungs to achieve the IP rating.

Of course,  power tool batteries have nothing similar.

Wouldn't want to try floating the battery without the plug/bung in place, but would like to see the video!

Incidentally, strange little green canoe/dory thing being used for the demo. Especially for a guy with a £2500 ish 3hp outboard, and a £90000 ish Tesla X. ?
Wonder why?

[Graham W]

Incidentally, strange little green canoe/dory thing being used for the demo. Especially for a guy with a £2500 ish 3hp outboard, and a £90000 ish Tesla X. ?
Wonder why?

The Gheenoe is made in Florida and is not cheap.  The motor in the UK is £1600.

[Peter Cockerton]

With the boat sailing at 4 knots and the outboard leg lowered I powered up the spirit before heading into wind to drop the main, I inadvertently asked it to go into reverse and it must have a protection device built in when the water flow is turning the prop as reverse request ignored. Didn't try it again at slower speed to see if it would activate with slower water flow induced spinning I'm wondering if this would actually be the case when maneuvering the boat in a tidal area and is it something to be aware off.

My modified 3 bladed prop worked a treat, not an easy mod on the plastic prop i purchased but it came good in the end. If anyone interested in what had to be done to get it to fit please ask.

Peter C

[Graham W]

I used my new eProp on Lake Bala on each of the past three days.  Compared to my old Torqeedo and my Suzuki 2.5hp from long ago, it's wonderfully quiet!

I measured the motor's power consumption with the original blue two-bladed prop and the Plus battery in low wind conditions and came up with the following:

60W = 2kn - 42nm calculated range
220W = 3kn - 17nm calculated range
520W = 4kn - 10nm calculated range
1,000W = 4.7kn - 6nm calculated range

This is with a gaping hole in the outboard well - my old well cover doesn't fit with the new motor and I'll have to make a new improved version.  I suspect that I will get better figures at the faster speeds once I put a lid on the fairly dramatic well turbulence.  It was noticeable that wind on the nose made for significant falls in speed.  Going into an F4 dropped full speed (1,000W) by at least a knot.

Using an electric motor in tidal areas is going to need a different approach to when I had my 6hp Mariner and could blast my way through anything.  Except over short distances, if there's headwind, sail.  And except over short distances if there's no wind, plan to motor with the tide rather than against it.