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This guy's building a nice homemade inverter/controller for a Prius A/C compressor:

http://www.diyelectriccar.com/...

Absolutely correct. Most electric cars (if you're keen, check out www.diyelectriccar.com) run at least 72V in a series string of at least 20 lithium-ion cells, and some run over 250V. Charging is done using a state-of-the-art high frequency AC/DC switching power supply with power factor correction, so that charging efficiency is maximized. For any given power transfer, double the voltage means half the amps, and that cuts the resistive power losses to 1/4, so it's always worthwhile to maximize the operating voltage within the bounds of the electronics (and safety considerations).

So, if you could help providing additional advice and information, it would be awesome.

How did this make the front page of /.? It's not news or even a vaguely new idea.

Converting an SUV, or just about any fossil fuel vehicle to an EV is well understood. There are kits available for a good number of cars.

There's a lot of information here: http://www.diyelectriccar.com/forums/ read it all. It will explain how to choose a good donor vehicle. An SUV might work, but choose a light one, preferably aerodynamic. Small (S10,ranger,etc.) pickup trucks are popular because you have carrying capacity for batteries (often under the bed).

Adding a range extender is extremely difficult, depending on how you do it. A generator charging the batteries is easy, but hopeless ineffiicient (and you need a big generator). Driving the wheels with either the existing engine, or the electric motor is do-able, but non-trivial and either solution has the weight of the electric drive-chain plus batteries and the fossil fuel drive chain.

If you really want some advice, convert a small car, or SUV to all-electric and develop a "pusher" trailer with a diesel or gas engine that you can hook up for longer journeys. There are already DIY and commercial plans for such trailers.

$50,000 is also excessive. Conversion kits run about $10K, add $10K of Lithiums, $20K if you choose something heavy and want a realistic range. Even if you start with a $10K donor your still not at $50K.

there is a common misconception that it's necessary to have a large ultra-expensive highly-polluting rare-earth-metal battery pack. you don't. the conditions for not needing a $25,000 battery pack (worth stealing) are as follows:

* the vehicle weight must be under 550kg (400kg EU Category L7E is perfect)
* low-rolling resistance tyres are essential
* you must be happy with a top speed of 60mph and a top cruising speed of about 55mph
* the frontal area of the vehicle must be no more than 1.5 sqm
* the drag coefficient must be 0.30 or less
* the full drivetrain efficiency must be no less than 80%

under these circumstances, which are perfectly reasonable for most peoples "commuting" needs, you can get away with putting in an off-the-shelf 240/120V AC 5kW or 6kW Diesel Generator and a "Fast Charger" with about 50 Amp output, and that is enough to keep the batteries continuously "topped up" or in fact just to directly drive the Electric Vehicle.

if you try to go BEYOND these circumstances (even putting in a 700kg vehicle) then you get into trouble, because the "Range Extender" now has to be an 8-10kW Diesel Generator, which now weighs 250kg not 100kg, doesn't pull the same level of fuel economy as a 5-6kW Generator (which work out at about 1 Litre per hour), and the exercise is a complete waste. so you have to stick to those conditions, and the maths works out very very well. almost... "too well", to the point where it's hard to believe the MPG figures.

the maths, principle and links to various sites is here: http://lkcl.net/hybrid_electric_vehicle/design_principle.html

and there's a discussion here:
http://www.diyelectriccar.com/forums/showthread.php/why-there-no-board-generatorsi-p261099.html

which if you look back about a week, you'll find a link to a LibreOffice spreadsheet where you can play and plug in your own "vehicle" line and confirm the maths i did, above.

the point is: *if* you do this sort of thing, then yes, large battery packs become irrelevant: you can treat that $500 lead-acid battery pack as a disposable (recyclable) item, and yes, you could even consider running the diesel generator to plug back into the National Grid. personally i think that'd be a bit of a waste of perfectly good Diesel, i'd say, but you could do it.

Sure! My sig points to my website, which contains not only Contraction Timer, but my EV Conversion Diary.

For guidance, I'd recommend the EV Discussion List (if you prefer email) or the DIY Electric Car Forums (if you prefer a web forum).

My car took about three years, all told. That includes out-of-state work by my brother, waiting on a custom part (that I probably should've just gotten machined locally), and local assembly. It also includes all the days we couldn't work on it: I've got three kids, so it wasn't even an "every weekend" project for me. More like two days a month.

If I were doing it again, and had the time to dedicate to it, I could finish a conversion in a month of effort after receiving all the necessary parts.

It should also be noted that advanced skills are not necessary. My car was built with no tools beyond a saw, a screwdriver, a drill, and a wrench. (Well, there was a big-ass wire cutter.) A ten-year-old designed the battery pack wiring.

After I become a self-sufficient millionaire, I intend to design and build my own AC motor and controller. THAT will be a serious outlay of work and skill acquisition.

Has anyone mentioned DIY Electric Car?

Lots of EV conversions. Folks have been building hybrids themselves but not as many as pure EVs.

Stay away from lion-ev. Haven't seen any good results from people dealing with lionev or Ken Curry

http://www.google.com/search?hl=en&q=Ken+Curry+fraud&btnG=Google+Search
http://www.google.com/search?hl=en&q=lionev+scam&btnG=Search

http://www.diyelectriccar.com/forums/showthread.php/evdl-lionev-7699.html
http://austinfarm.org/homegrown/downloads/lionev.txt
http://bulk.resource.org/courts.gov/c/F3/461/461.F3d.452.05-5173.05-5090.html

Also stay away from Spark-EV
http://www.autobloggreen.com/tag/spark-ev/

They're still driving gas cars!!

Go electric - www.diyelectriccar.com

There are too many politics involved with the oil industry and electric cars, so we choose to build our own. http://www.diyelectriccar.com/