At max torque, there is max current - if you're doing a hill start you can be pushing several hundred amps. Many controllers will limit the current - if you want a high current limit, you'll need to pay for it. Also, manual boxes are far more fun.

Another interesting thing is that you don't need a clutch either! Since the rotor in an electric motor is so light, you can use the synchros to change the speed of the rotor, instead of a flywheel. A clutch will make the gear changes faster though, and will be much nicer on the synchros, I imagine.

I think what you're saying is you don't need a clutch because when you release the Go Pedal the motor will freespin with the movement of the car and therefore instead of needing to match the speed of the wheels to the RPM of the engine the gearbox simply engages and brings the motor along with it once the teeth engage.

Having driven a manual all electric EV, I would highly recommend the use of a clutch. Although not necessary, it does make gear changes smoother. But from idle the clutch is not necessary.

A gearbox is useful because although there is losses, under some driving conditions a gearbox will improve range due to a lower amp draw during acceleration. You would want a fairly torquey series-wound DC motors (say Warp 9 or Warp 11) without a gearbox (direct drive, usually only done on RWDs as the diff is fairly integral with a FWD gearbox), and a high current controller (say 1000A Cafe Zilla). However, with a gearbox, a smaller and less expensive and more efficient setup can used. For example, like a 3-phase PMAC setup which can be purchased from the USA (which also has the advantage of being regen capable).

The use of Thundersky 200AH LiFePO4 batteries has become the norm nowadays for acceptable range and weight.

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1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T

Electric motors make big torque, but... Really, is it that much? Is there anyone on the forum who can't - with the correct breaker bars - torque their CV's? That's 150-175Nm on a disc brake front end. That's more torque than almost any Mini motor in the world. The motors in EV's tend to be not that much more than that... And they tend to run reasonably low power outputs. How many EV's are there out there that run higher bhp's/kW's than a decent 1275?

Gearboxes are needed for two reasons. Firstly, acceleration without gearing would be sluggish without reducing the ratio. Even big modern cars with 500-600-700Nm of torque have gearboxes. Yes, that's to make them even quicker, but, given the gearbox is a torque multiplier, if 1st is 3:1, it means that they're putting out 1500-1800Nm at the diff (yes, that's assuming no drivetrain losses, which I realize is fiction). A Mini with 100Nm (75lb-ft) going through 3:1 is 300Nm at the diff (again, ignoring drivetrain losses, but also ignoring that 1st is shorter than that in a Mini). How many electric motors output that, and what sort of battery pack would you need to do that? Secondly, with fixed gearing set up for acceleration, top speed would be very low. Look at the top speed on any EV - they're all pretty low. The motors spin much higher than car petrol motors, but they don't rev to infinity.

My belief is that, if you're going to run an EV, it's better to go A/C. Then you can run regen. You can get big motors more easily. The problem is with controllers. My belief is that, whilst being no cheaper and likely significantly dearer (because of A/C controller cost), the best solution is high voltage/low amperage A/C. Why high voltage? The higher the voltage, the higher the revs the electric motor can run. The higher the volts, the lower the amps for the same power. Which means smaller wire diameters. Which means it's (arguably) less dangerous (current - amperage - is the killer, not voltage).

That said, I think Phill's conversion is very cool, and I'd love an update.

FYI,

Here's a link to a list of threads about classic mini electric conversions:

http://www.diyelectriccar.com/forums/search.php?searchid=520991

Apologies for the dodgy link. That forum is good; once there use the search option top-right.

Just came across a Kiwi doing a conversion and sharing what he discovers along the way:

http://carrott.org/blog/



regards,
Chris.

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2 steps forward, 1 step back

scrap the hole car gearbox idea!
use a CVT (Continuously variable transmission) like the ones they use in golf carts, get the motor to its greatest torque, and keep it at that rpm, and use the CVT to drive off, and accelerate

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1969 Blue Mini K, 1330cc, Weber 45, polished aluminum roll cage, Race seats, 4 point harness, full rewire incorporating 8 fuses, 6 relays and new headlights just needs tyres front shocks and a windscreen til re-register

Here's a more recent blog on Tumblr covering in detail an electric mini conversion:


http://evmini.ca/


Chris.

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2 steps forward, 1 step back

Norwegian Mini Ute converted to LiFe propulsion. Beautifully engineered:

http://www.youtube.com/watch?v=8uG2PQk0OGM

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2 steps forward, 1 step back