The LEAFs Mighty Mite Motor

[ELROY]

I was installing my HID foglights this weekend and was surprised at how small the actual motor is. Even with its water jacket, etc, the whole unit is less than a foot long.

Also, I know many people have been discussing getting different wheels that are lighter than the originals. So I decided to weigh the stock wheel and tire. 40lbs, 5.6 oz on a postal scale. So if going to a 17" wheel and tire, it is really easy to gain weight, when you should strive to be no heavier than stock.

And finally, the HID foglights reduce power draw from 55watts for the halogens, to 35 watts for the HIDs. They are so much brighter. Our foglights tend to aim right towards the ground, so not a strong glare for oncoming traffic. They definitely have a lot of spread out light in general, lighting up the sidewalks and lawns of the houses,etc. Big difference. The ballast is very easy to mount, and other than that it just intecepts between the harness plug and the bulb.

 

[adric22]

yeah, I have been amazed how small the motors are in production EVs and hybrids. Because anyone who has built a custom EV will tell you the generic motors are much larger for the same or less performance. Of course, they tend to be DC, air-cooled, and use brushes.

 

[jopickens]

Where the LEAF has a 3 phase, AC, brush-less motor routed through ~8:1 gear reduction?

 

[TickTock]

Yeah, brushless motors are really pretty cool. Unlike brushed, DC motors, the coils are on the outside so it is much easier to move heat away enabling you to push a lot more current through a lot less wire. We used 18hp brushless motors for a battlebot and those were just a little bigger than a D-cell battery (we used a 20:1 reduction ratio). Didn't have any problems keeping the motor cool (enough). (but the motor controller was a different story...)

 

[rawhog]

Details on the lights you used please.

 

[LKK]

I'm amazed the Leaf's motor is smaller than the 3 hp motor in my table saw!

 

[GeekEV]

We used 18hp brushless motors for a battlebot...

Which bot? Any I might have seen on TV?

 

[caffeinekid]

Not much larger than the one in my dryer. This is one of my favorite subjects to teach inquiring young (and older) minds about- how much mass can be moved with such a relatively small electric motor. So many interesting elements of science and engineering involved.

On a related note, Tesla is brilliant IMO for displaying theirs in their stores.

 

[adric22]

On a related note, Tesla is brilliant IMO for displaying theirs in their stores.

Yeah.. Tesla's drive system is really interesting how the motor and the inverter/controller are all crammed into essentially the same unit. In many ways that is a good design, although it might be irritating if you ever need to replace the controller. Of course, I'm not a fan of rear-wheel drive, which Tesla is using. While it may look cool when peeling-out, it really is inferior in my opinion for handling, especially in wet or low traction conditions. I'm not sure if they could have still had their "frunk" with front-wheel drive, though.

 

[cwerdna]

Of course, I'm not a fan of rear-wheel drive, which Tesla is using. While it may look cool when peeling-out, it really is inferior in my opinion for handling, especially in wet or low traction conditions. I'm not sure if they could have still had their "frunk" with front-wheel drive, though.

Most sports car drivers (former one myself) would disagree w/you about RWD with respect to handling, at least in dry conditions. They would refer to FWD as WWD (wrong wheel drive). Problem w/FWD is the car ends up being front heavy instead of having a more balanced weight distribution and you have the problem of the front wheels doing too much: propelling the car, steering it and doing most of the braking.

You'll notice that most good sports cars and sport sedans/coupes are RWD and some are AWD. (Examples: Porsche's line of sports cars, Corvette, Nissan 370Z, Infiniti G37, Miata, Mustang, "Toyobaru" BRZ/FR-S, Acura NSX, BMW 1 and 3-series, Mitsubishi Evo, Subaru WRX, etc.)

Also, when you accelerate, the rear squats due to weight transfer and on RWD car, those are the driving wheels, so that aids w/traction as well.

I'd taken my former 255 hp Maxima (FWD) and 287 hp 350Z (RWD) to the drag strip before. The Maxima would spin its wheels if floored, yielding not the best times. It was better to accelerate w/the gas pedal partway down and then floor it, once I started moving. My Z didn't have such issues w/traction.

I wish the Rav4 EV were RWD.

Yeah, I doubt they could have their frunk, or much of one if it were FWD.

 

[davidcary]

Now I don't personally know what Elon was thinking but could you imagine the Tesla with AWD? He wanted to build the best car in the world (which it isn't) but you can't come close without AWD.

There would be no debates about beating an M5 - with the torque and AWD, the M5 would have needed 1/2 mile to catch up.

 

[adric22]

You'll notice that most good sports cars and sport sedans/coupes are RWD and some are AWD. (Examples: Porsche's line of sports cars, Corvette, Nissan 370Z, Infiniti G37, Miata, Mustang, "Toyobaru" BRZ/FR-S, Acura NSX, BMW 1 and 3-series, Mitsubishi Evo, Subaru WRX, etc.)

I understand the benefits of RWD under certain scenarios. But I used to have a 1992 firebird and I can't even count the number of times I nearly fishtailed into a ditch because it was wet and I was trying to turn a corner and accelerate. And no, I wasn't even accelerating that hard. Oh, and driving on ICE? forget it. I've never had that issue with front wheel drive. I think for the sports-car enthusiast, fine.. enjoy your RWD. But for the average commuter driving to work everyday, FWD is much better and safer.

 

[Herm]

Perhaps Tesla will develop a smaller motor for their next generation low cost family vehicle.. and then stuff it in the frump of the S.. after all Musk is a fricking rocket scientist

 

[ELROY]

Perhaps Tesla will develop a smaller motor for their next generation low cost family vehicle.. and then stuff it in the frump of the S.. after all Musk is a fricking rocket scientist

The motor is small enough to have in the front and still have a reasonable size frunk. The car could have over 800HP on demand and around 900lbs tq.
And while cruising, still get 70mpe+. There would no need for a transfer case and extra propeller shafts, etc. It could all be balanced electronically. On the other hand, if you look up "electric supercars" on YouTube, you will come across several 800-1000+ electric cars. For some reason, some of them have a 0-60 times in the high 3 second range. Barely faster than the heavy Tesla S 4.1 second achievement. Perhaps the Tesla is the over achiever here. When battery technology gets better, I would love to see what Tesla could do with a twin motor supercar.

On the benefit side..besides no transfer cases...you would do away with huge exhaust systems...fuel tanks and emission systems, etc. There is something wonderfully simple about electric cars. If they truly do double battery efficiency, the gas engine may become a rare thing.

 

[TomT]

That is exactly what the X does in its AWD model. I saw a rolling chassis of it at the opening day festivities they had at the Santa Monica store.

Perhaps Tesla will develop a smaller motor for their next generation low cost family vehicle.. and then stuff it in the frump of the S.. after all Musk is a fricking rocket scientist

 

[TonyWilliams]

I wish the Rav4 EV were RWD.

Yeah, I doubt they could have their frunk, or much of one if it were FWD.

The Tesla Model S and X are both likely to have FWD (with RWD) next year. The Rav4 is just nutty with FWD, and it should absolutely be RWD.

 

[dgpcolorado]

For those of us who live in snow country there is no comparison between FWD and RWD. I drive both and FWD wins hands down. While AWD or 4WD is preferred on snow, FWD cars generally work quite well in snow country. RWD cars are practically worthless on snow.

I don't care about dry pavement performance in the sunbelt or race tracks, I care about safety and traction in slick conditions.

 

[ELROY]

This will give you a better perspective of the engine/trans drivetrain on a RWD V10 Viper. You can see the engine/trans highlighted in dark black.

Now look at how small the engine/drivetrain (highlighted in black) is on the Tesla S. Now you can see what a simple task it would be to put an engine on the front axle too, as far as packaging is concerned. Also note how small the interior space is on the 2 seat Viper. Not to mention it is over 1400lbs lighter than the Model S. Yet Road & Track said that the without doing a clutch dump in the Viper...the Model S will beat it 0-60mph if both cars just romp on the throttle at a slow speed.

Interesting article by Road And Track. After being selected as Motor Trend car of the year. R&T says the Model S is "the most important American car in a lifetime."

http://www.roadandtrack.com/car-reviews/road-tests/road-test-2013-tesla-model-s" onclick="window.open(this.href);return false;

 

[DaveEV]

I understand the benefits of RWD under certain scenarios. But I used to have a 1992 firebird and I can't even count the number of times I nearly fishtailed into a ditch because it was wet and I was trying to turn a corner and accelerate. And no, I wasn't even accelerating that hard. Oh, and driving on ICE? forget it. I've never had that issue with front wheel drive. I think for the sports-car enthusiast, fine.. enjoy your RWD. But for the average commuter driving to work everyday, FWD is much better and safer.

On a modern car with traction control and stability control, the days of fishtailing a RWD car into a ditch are over.

 

[LEAFfan]

This will give you a better perspective of the engine/trans drivetrain on a RWD V10 Viper. You can see the engine/trans highlighted in dark black.

Now look at how small the engine/drivetrain (highlighted in black) is on the Tesla S. Now you can see what a simple task it would be to put an engine on the front axle too, as far as packaging is concerned. Also note how small the interior space is on the 2 seat Viper. Not to mention it is over 1400lbs lighter than the Model S. Yet Road & Track said that the without doing a clutch dump in the Viper...the Model S will beat it 0-60mph if both cars just romp on the throttle at a slow speed.

Interesting article by Road And Track. After being selected as Motor Trend car of the year. R&T says the Model S is "the most important American car in a lifetime."

http://www.roadandtrack.com/car-reviews/road-tests/road-test-2013-tesla-model-s" onclick="window.open(this.href);return false;

Not only did the Model S beat the Viper 0-60, but easily beat it in the quarter mile.