Torqeedo Outboards?

[nestawayboats]

Ian, is it ok to partially charge a Torqeedo battery on a regular basis?

Lithium batteries of this chemistry have very little in the way of "memory effect", so it doesn't matter much what state you charge them from, nor what state you charge them to. You don't have to flatten them before charging, nor fully charge them before use.

The more important effect on longevity is how you store them in the long term; unlike lead acid batteries this type "prefers" to be stored partially charged. In fact the Epropulsion battery self-discharges to about 80% after a couple of months, if it's been left in a higher state of charge than that.

Both types "lose" between 2 and 4% per year just by existing (as do all batteries), and whether it's 2 or 4% depends mostly on how they're stored - because they spend more time in storage than being used. So if you're putting one of these batteries away for more than, say, a month, ideally run it down a bit first, to somewhere between 50 and 80%. They also prefer not to be very hot or cold, but in the UK that doesn't tend to be much of an issue.

Ian Thomson
Nestaway Boats

 

[ghostlymoron]

Surely the major disadvantages of a torqueedo are price, endurance and recharging. If you can put up with short trips, have plenty of dosh and a recharging system, they're are great. Otherwise, petrol is superior.

 

[oldharry]

Surely the major disadvantages of a torqueedo are price, endurance and recharging. If you can put up with short trips, have plenty of dosh and a recharging system, they're are great. Otherwise, petrol is superior.

Does anyone make a 'poor mans version' of the Torqueedo, probably using a conventional car battery to power it but capable of giving realistically usable performance in a dinghy? The cheaper 'trolling motors' seem to me to be just that, a troll; for all their thrust claims they are usually pretty gutless when the going gets at all tough and you actually need the sort of power the Torqueedo produces. Is there no half way house with electric outboards? Environmental considerations (including the smell in the boot of my car) appeal, but like many eco friendly solutions, the cost of a Torqueedo is prohibitive for the amount I would use it.

 

[Bouba]

Lithium batteries of this chemistry have very little in the way of "memory effect", so it doesn't matter much what state you charge them from, nor what state you charge them to. You don't have to flatten them before charging, nor fully charge them before use.

The more important effect on longevity is how you store them in the long term; unlike lead acid batteries this type "prefers" to be stored partially charged. In fact the Epropulsion battery self-discharges to about 80% after a couple of months, if it's been left in a higher state of charge than that.

Both types "lose" between 2 and 4% per year just by existing (as do all batteries), and whether it's 2 or 4% depends mostly on how they're stored - because they spend more time in storage than being used. So if you're putting one of these batteries away for more than, say, a month, ideally run it down a bit first, to somewhere between 50 and 80%. They also prefer not to be very hot or cold, but in the UK that doesn't tend to be much of an issue.

Ian Thomson
Nestaway Boats

Thank you very interesting!

 

[Aeolus]

Surely the major disadvantages of a torqueedo are price, endurance and recharging. If you can put up with short trips, have plenty of dosh and a recharging system, they're are great. Otherwise, petrol is superior.

Presumably you include smelly, polluting, noisy, more difficult to store, more difficult to start, heavier and more dangerous amongst petrol's superior characteristics.

 

[RupertW]

Surely the major disadvantages of a torqueedo are price, endurance and recharging. If you can put up with short trips, have plenty of dosh and a recharging system, they're are great. Otherwise, petrol is superior.

Price - absolutely a disadvantage - if price is important then I wouldn’t have gone for it. Recharging is easy even with 3 or 4 return trips a day of half a mile each way - the domestic battery bank is far bigger than the Torqueedos so inverter on and 10% an hour into the battery with not much impact.

And as we are rarely near a petrol station I don’t want to rely on a bus or a taxi to find one every now and again when I can effectively use sunlight as fuel.

 

[Bouba]

And a Torqeedo’s charge can probably be stored longer than modern petrol can

 

[pvb]

Price - absolutely a disadvantage - if price is important then I wouldn’t have gone for it. Recharging is easy even with 3 or 4 return trips a day of half a mile each way - the domestic battery bank is far bigger than the Torqueedos so inverter on and 10% an hour into the battery with not much impact.

And as we are rarely near a petrol station I don’t want to rely on a bus or a taxi to find one every now and again when I can effectively use sunlight as fuel.

I just charge mine direct from the boat's 12v batteries, using a DIY charging lead. I made the lead from an old laptop charger (the Torqeedo manual gives the dimensions of the plug).

 

[pvb]

Both types "lose" between 2 and 4% per year just by existing (as do all batteries), and whether it's 2 or 4% depends mostly on how they're stored

I think you meant to say per month. Torqeedo say 3.6% per month in optimal storage conditions.

 

[RupertW]

I just charge mine direct from the boat's 12v batteries, using a DIY charging lead. I made the lead from an old laptop charger (the Torqeedo manual gives the dimensions of the plug).

What rate to you get into the battery per hour - I get about 50 wh/hr by inverter and have been told direct 12v much slower.

 

[pvb]

What rate to you get into the battery per hour - I get about 50 wh/hr by inverter and have been told direct 12v much slower.

No idea, but I'm not in any great hurry. After using the Torqeedo I just plug the battery in to charge and leave it overnight.

 

[ghostlymoron]

20 miles range is approx five hours..........in a dinghy? That's a long time.

I like the idea of the Torqueedo, but it would have to change significantly before I would consider one. I'm not particularly interested in speed, but I would need a moderate increase in range, a significant reduction in price and a significant reduction in charging time. If it could give me close to 20 miles range with recharge in a couple of hours and all at a price premium of no more than 50% over a 2.5hp outboard from a decent manufacturer, then it would be a definite option, but without those improvements, it is just impossible to justify.

 

[Alan S]

What rate to you get into the battery per hour - I get about 50 wh/hr by inverter and have been told direct 12v much slower.

50 Watt hours per hour? That's a strange way of saying 50 Watts! ☺

 

[RupertW]

50 Watt hours per hour? That's a strange way of saying 50 Watts! ☺

Miles per hour per hour is not miles

 

[maby]

20 miles range is approx five hours..........in a dinghy? That's a long time.

My primary use of the outboard is providing support for my wife and others windsurfing and paddleboarding. I may be buzzing around the bay or harbour for a significant time. Admittedly, 20 miles is very much the upper limit, but once the battery is flat, it aint going anywhere for quite a few hours, so I do want some spare capacity.

 

[Alan S]

Miles per hour per hour is not miles

Energy is measured in Watt hours (Wh)
1 Wh = 1 Watt x 1 hour.


50 Wh per hour is 50 Watts x 1 hour ÷ 1hour
The hours cancel out leaving you with 50 Watts.

It's not equivalent to miles per hour per hour, that would be 50 miles ÷ 1hour ÷ 1hour.

 

[grumpy_o_g]

50 Watt hours per hour? That's a strange way of saying 50 Watts! ☺

Not really - it's saying that it takes one hour to put 50 watt hours in the battery. You can't put it in any faster but you can take it out a lot faster unfortunately. If you are drawing 200 watts it'll only 15 minutes to empty it (in other words one hours charge will give a certain number of minutes at full throttle but a lot more minutes at half throttle).

 

[Bouba]

My primary use of the outboard is providing support for my wife and others windsurfing and paddleboarding. I may be buzzing around the bay or harbour for a significant time. Admittedly, 20 miles is very much the upper limit, but once the battery is flat, it aint going anywhere for quite a few hours, so I do want some spare capacity.

That is exactly what I do! Apart from wanting no petrol aboard the mothership, my wife wanted a quiet motor so I could accompany her without ruining her day.
In reality the main purpose is to take the dog to the beach for his walks. Dogs don’t have a problem with electric but can be scared of a noisy outboard. Plus you don’t have to get the dog to make room while you pull start it.
I have a 2.6m aluminum rib, with the Torqeedo. The boat is put on an off the mothership with a derrick (that I electrified and now uses remote controls). I have a generator for recharging, and a solar panel (this summer I will (finally) fit my inverter which will give silent charging). I am extremely happy with this setup (and say so every time I use it!). But I don’t get the speed (perhaps 4.5 knots flat out) or range (probably single figures but I’ve never flattened the battery to find out) that you people get. But I do have a tiller extension, that I’ve never fitted (a big job!) so weight distribution is probably my main problem. But like I say I wouldn’t go back to petrol unless I wanted to go waterskiing (which I don’t)

 

[ghostlymoron]

Is it only me that finds the term 'mothership' a bit pretentious when a applied to a sailing yacht?

 

[Bouba]

Is it only me that finds the term 'mothership' a bit pretentious when a applied to a sailing yacht?

I deliberately used the term because I’m a motorboater and I didn’t want any animosity from a mainly sailing forum so I used a gender neutral term it was only to obfuscate not to deceive