EV drivetrain availability?

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Talkiet

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#207631 5-Jan-2017 22:06

For a long time I have wanted to build an electric racing car, or at least electric kart. In about 8 months I'll be in a position where I can actually start on it (Garage in new build will be large enough to allow this sort of foolishness!) but have a bunch of things I need to learn first...

I'm not concerned about chassis design or suspension or brakes etc. What I don't know there I can learn - there's a lot of well established material on it, and my time maintaining my 7 and helping dad build his put me in a reasonable position there.

Powerplant and drivetrain however are where I have a vacuum of anything like a concensus in established circles. I have thought of these options...

A) Take the wimpy way out and just use a bike engine... Pros: Easy, lots of bang for buck. Cons: Not cool, no performance reverse.

B) Get a wrecked Leaf and use the drivetrain from that... Pros: Should work just fine, good performance. Cons: Not sure how much of the system could be cut off/removed while still having it work. I don't want a flash dash, I don't want ABS or VDC...

C) And here's where I am after information really... Are there locally available "kits" or shopping list options for buying just the powerplant and drivetrain for an EV? ie. Get this motor, this charge controller, this set of batteries etc. (Like http://www.electricmotorsport.com/ev-parts/motor-drive-kits )

The other thing would be that if I end up going for option A, I'd try and make the rest of the chassis and drivetrain reasonably agnostic of the engine... So perhaps it starts with a bike engine and box, but en electic system could later be grafted on to the tailshaft...

Anyone done anything like this? I'd also consider buying a pre-made chassis so suggestions welcome there as well.

Cheers -N

ps. No intention of going road legal.

Please note all comments are from my own brain and don't necessarily represent the position or opinions of my employer, previous employers, colleagues, friends or pets.

RUKI

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#1699138 5-Jan-2017 23:32

If testing traction batteries for your project will be required I may be able to help you with that on my Analysers in Auckland.

Couple of companies I know in USA do EV conversions. Everything though is sourced from within USA and my quick estimate - $15K USD excluding delivery to NZ does not worth the efforts when you can just buy used working EV from Japan for that money.

There are already at least 3 Leaf wrecks in NZ and I can get you in touch with the owners, but Leaf is complex and it's systems are integrated into 3 CAN BUS. I have built virtual one from Leaf computers at some stage. Reverse engineering CAN bus to eliminate /emulate missing parts will take so much time and does not worth the efforts. I looked at using Leaf on-board charger at some point - cheaper to buy of the shelf or built your own than make that one working standalone (USA EV / Leaf Gurus, who took part in LeafSpy Development are of the same opinion).
FYI - if you interested here is my brief video of what's inside Leaf on-board charger. I did not comment it - as it is straight forward for EE and I made it purely when we were discussing possibility of reverse-engineering it: Dismantling Leaf On-Board Charger

Aredwood

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#1700398 9-Jan-2017 05:06

How crazy do you want to go? http://www.metricmind.com/products/gx629-81-ev-transaxle-assembly/

Definitely cheaper just to get a crashed Leaf and mod the chassis. Unless you are going to go homebrew. And get a big old DC motor from an elevator. Or maybe one of the old Wellington trolley busses? And use 30 or so 12V car batteries wired in series. With control based on a really big rotary switch and lots of resistors. Such a car would be excellent for doing burnouts, but not much else. As resistive control with no regen braking is very wasteful of power. And 30 lead acid batteries will be very heavy. Just hope you never get a short circuit. As 400Volts DC at thousands of amps in a short circuit will do some very serious arc welding. And completely vaporise whatever caused the short circuit.

Sidestep

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#1700447 9-Jan-2017 10:04

Not exactly an EV (more like a Golf Cart on steroids) but I have an E-Gator left. Might make an electric cart?
Just sold it's twin for $1,000 a few months back to a guy who was going to part it out & keep the drivetrain for a project.

48V DC motor, 400A controller, Auto Taper/shut off charger. Does about 30km/h forward, 10km/h in reverse as is.
Has 8 Trojan 6V batteries. The weight of them is the problem with these things.
Still carried 2 people and a load of soil in the tilt tray no problems.

This one was parked when the key broke off in the ignition 2 years ago. Batteries were fully charged then.

Talkiet

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#1700455 9-Jan-2017 10:09

I'm not after a small runabout or 'fun' kart... Performance wise I'm after something like this...

https://www.youtube.com/watch?v=cZGV5fImxDk&t

I already have a pretty quick road legal toy (0-100k in just over 4 sec) so I am after something ludicrously fast now (think 0-100 in 2.5 seconds type quick)

The more I look into this the more it looks like the only feasible (affordable) approach is a very powerful bike engine in a glorified kart chassis... That's ok though - that's probably going to give the biggest bang for buck ;-)

Cheers - N

Please note all comments are from my own brain and don't necessarily represent the position or opinions of my employer, previous employers, colleagues, friends or pets.