I just saw "Who Killed the Electric Car," and as a result one of the first things I did when I got home was that I checked out:

http://www.teslamotors.com/

Y'all should too.

 

It's a Lotus Elise with an electric drivetrain instead of the Toyota 1.8L 4-cyl engine.

It's going to look awesome, go fast as hell, and be so expensive that I'll never be able to buy one

 

Or risk being crushed . . . for no good reason.

Bob Wilson

 

Part of me wants to applaud companies like this for trying something innovative. Another part wants to smack myself on the head and say, "this **** again?" Most of these guys just sit on designs, concepts, and models, for years. The only ones who go for a ride are the VCs.

 

What do the Viet Cong have to do with this?

Oh. Venture Capitalists? Nevermind.

 

Lotus made a concept electric Elise back in 1998, the Zytek Elise.

It was stupidly fast, faster than the gasoline version, and they said they would put it into production as soon as they thought the market was ready for it. Seems they think the American market may now be ready.

 

I've 'day dreamed' about what it would take to make my own, electric vehicle and came up with this approach based upon starting an NHW11:

1) Remove the 1500 cc ICE
2) Install an electric clutch operated, ICE shaft to transaxle (100 ft lb rating)
3) Couple the transaxle pump to MG2 (ring gear of PSD)
4) Replace the hybrid vehicle ECU with a single-board, suite of ucontrollers
5) Write the software
6) Integration test using existing battery pack and ECUs
7) Assemble second battery pack in area formerly holding ICE
8) Add phase-change cooling to transaxle using radiator for condensor
(a liquid hydrocarbon, propane or butane)
9) Separate inverter cooling loop from transaxle loop
10) Integrate system

NOTE: At speeds above 42 MPH, the ICE shaft will have to 'clutch' open to prevent over-rev of MG1. This reduces available HP to 40 above 42 MPH.

NOTE2: Fixing the planetary spider gears would allow MG1 operation in parallel with MG2 and remove the 42 mph speed limitation. Due to current limitations, it would reduce low-speed accelleration but it would improve the top-end.

Expected specifications, from 0-41, the vehicle will have about 65 hp with an impressive amount of low-end torque (current limited by inverter.) It should cruse up to 70 mph on the 40 hp MG2. But if MG1 is configured to run in parallel (locked spider gears), the vehicle should reach speeds in excess of 100 mph.

Bob Wilson

 

If I follow, then, you're saying have no engine, simply the two elecrtic motors working together. The "clutch" is then a method of locking the planet carrier in place, similar to how many automatics shift, or letting it freewheel. Interesting idea, you also have the advantage of still having variable ratio by controlling which path (MG1, MG2) the most power takes at low speed, which should be good for low speed climbing. Your second battery I presume would be rated for steady discharges, and the original hybrid pack would act as it did before, for surges of peak power.

 

You've got the major parts correct. The "clutch" has to do with the Prius transaxle MG1 gearing in the CVT part of the transmission. If the engine is off and the car exceeds 42 mph, MG1 can over-rev and potentially fall apart. By opening the "clutch" on the former ICE shaft, it can free-wheel and keep MG1 speeds within the safety range. Unfortunately, MG1 won't be able to add power above 42 mph.

The other approach is to 'lock' the spider gears in the planetary gear carrier (spot weld.) This effectively ties MG1 to MG2 with a 1:1 gear ratio. Now MG1 won't over-speed but it has no gear ratio to provide low-end torque. Effectively, the car becomes a split-motor, 65 hp, electric vehicle. As long as the startup torque (starting up a hill) is not exceeded, it should work quite nicely. Experiments with reverse suggest MG2 is fully capable of handling many grades already.

The second battery can be any chemistry and I would use a computer controlled, DC-to-DC converter to handle the loads. It would be entirely practical to use a 'primary cell' battery (one without a recharging capability) that could be wrenched down for replacement. Then the 'primary cell' could be refurbished outside of the vehicle. Alternatively, it could be an array of Li or air-metal cells. The options are much wider than you might believe since this second battery only has to provide 'distance' power.

My preference remains for an air-metal cell that generates an inert metal oxide. As for storage of the oxide, there would be this empty fuel tank and the space wasted today for the exhaust system. Mechanical screws could easily move the oxide to the vehicle storage areas. Later it could be blown out by compressed air for subsequent reduction back to metal, outside of the vehicle.

Bob Wilson

 

I don't understand the engineering talk very well, but the reports that it's based on the Lotus are said to be untrue rumors in more recent press reports. But I guess we'll all find out Wednesday.

It does look like a Lotus under its covers, though.

As for only VC's driving it, I'm of the impression they're trying to bring it in at a price way under the $600,000 Venturi: http://www.venturi.fr/us/fetish/specs/specs.php3