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Discussion Starter · #1 ·
For my solar boat project (Login • Instagram) I'm searching for two identical, used EV drivetrains. Nissan Leaf, Renault Zoe or such would be good - lower voltage systems would be welcome, but are not a must.

The more complete the drivetrain is, the better (motor, inverter, gear reduction, electronics, throttle etc.
 

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Among mainstream regular road cars (rather then Neighborhood Electric Vehicles in the U.S. or quadricycles in Europe), almost all will run at nominal pack voltage of about 360 V. The Mitsubishi Outlander PHEV isn't a pure battery-electric EV, but the rear drive unit is essentially a normal EV drive unit of about the right power level, and the system voltage is only 300 V (80S @ 3.75V/cell).

Are you looking for a continuous power rating of 50 kW per unit, or only a peak output at that level? While automotive engine power ratings are for essentially continuous duty, automotive electric motor ratings seem to be for a peak of what may be only seconds, with continuous output (limited by cooling) of perhaps half that peak.

Do you really want the whole gearbox for this application? They will all have an unwanted differential, and the gear reduction ratio will result in an output speed which is very low for a propeller, unless you're running an enormous prop. I do understand wanting to avoid the need for a separate reduction gearbox or custom reduction drive (such as a belt system).
 

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Discussion Starter · #3 ·
Hi,

at cruise speed, each system outputs less than 10kW. But for storms/strong currents, some extra (continuous) power would be good. Leaf is 80/40 I believe, ACP Gen 3 is 150/50. Those are probably in a good range.

Desired RPM range is 0-1300, since I do have quite large propellers with four blades.
 

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Hi,

at cruise speed, each system outputs less than 10kW. But for storms/strong currents, some extra (continuous) power would be good. Leaf is 80/40 I believe, ACP Gen 3 is 150/50. Those are probably in a good range.

Desired RPM range is 0-1300, since I do have quite large propellers with four blades.
You'll definitely need a gear reduction box to keep the RPMs that low. Most production EV motors are designed with a peak RPM of around 8-12k rpm, so you'll likely need at least an 8:1 gear reduction. If you keep the drive units intact with the original gear reducer, and find a way to "lock" the differential, that would probably work fine.

It sounds like a pair of LEAF drive units would probably work pretty well, but as brian_ said, you'll need a system that is ~360v nominal (96s). You might be able to run a lower voltage (maybe even as low a 200v?), but keep in mind that by running a lower voltage, you'll also be decreasing the power you can put through it. If you want to keep the system voltage lower, you'll likely need to go with some off-the-shelf motors, such as a HyPer 9 (38kw continuous, 88 peak).
 

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at cruise speed, each system outputs less than 10kW. But for storms/strong currents, some extra (continuous) power would be good. Leaf is 80/40 I believe, ACP Gen 3 is 150/50. Those are probably in a good range.
Thanks for the power requirement clarification - that looks promising for EV units, since any car needs substantially more than 10 kW continuously to cruise at highway speed.

Desired RPM range is 0-1300, since I do have quite large propellers with four blades.
The speed range is lower than I would have guessed, and a promising match for the complete drive units.
 

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Discussion Starter · #6 ·
You'll definitely need a gear reduction box to keep the RPMs that low. Most production EV motors are designed with a peak RPM of around 8-12k rpm, so you'll likely need at least an 8:1 gear reduction. If you keep the drive units intact with the original gear reducer, and find a way to "lock" the differential, that would probably work fine.

It sounds like a pair of LEAF drive units would probably work pretty well, but as brian_ said, you'll need a system that is ~360v nominal (96s). You might be able to run a lower voltage (maybe even as low a 200v?), but keep in mind that by running a lower voltage, you'll also be decreasing the power you can put through it. If you want to keep the system voltage lower, you'll likely need to go with some off-the-shelf motors, such as a HyPer 9 (38kw continuous, 88 peak).
I've talked to someone who has previously used a Leaf drive system on a boat by welding the differential - looks like he'll help me out there, which is great.

The high voltage I've accepted as something I won't get around. 96S is what I'm currently looking at.

HyPer 9 looks great, but I'm only using second-hand components for this project, and couldn't find one of those. Also, they're about twice the price of the Leaf system, while the latter will make it easier to find spare parts when cruising around the world, so I'll likely go with that.
 

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For my solar boat project (Login • Instagram) I'm searching for two identical, used EV drivetrains. Nissan Leaf, Renault Zoe or such would be good - lower voltage systems would be welcome, but are not a must.

The more complete the drivetrain is, the better (motor, inverter, gear reduction, electronics, throttle etc.
Hello Lichtenstein.

I can ship you two ready made and tested Nissan Leaf drivetrains with open source PCB installed.

Let me know if it would be of interest.

I run a side business apart from my job at Candela Speedboat.

/ Victor Norberg
 
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