Virus

If there is any electro / and mechanical (engineers) guys around here that have some free time between The family, Christmas, and New years arrangements, I would like to pop a question.

(( Please lets not make it a political mudslinging contest or some thing, look at the matter/question at hand and come up with a –YES it can work and get down to do it (how many stator, how thick, how wide etc,) or –NO it won’t work and we leave it. Looking at the soaring price of fuel and the dependability of the people on their respected governments for the demand and supply thereof at a (their) price . . . we all know the rest.))

Myself with absolute zero back ground in these fields, (but being an optimist that usually find a light in every tunnel) have been pondering this thought for almost 6 years and would like to hear some theories and the feasibility of modifying a standard production car to run similar like a Hybrid (like the Toyota Prius and the like) or maybe just straight electrical.

iaw. with the standard petrol engine in place (or removed) BUT with the brake drums, calipers and disks removed and replaced with a custom made electrical pancake type motor and electronics. That can be standard fitted to most cars, yours and mine. 90% of people driving, especial in towns, do not use the boot area and can be modified to fit batteries, etc.

I know there are, and I have followed numerous conversion projects on the web, including the Tesla Electric car (absolutely awesome) , also there is a Mini Cooper running to the above spec (four pancake motors, with astounding specs), all out of reach to the general public, unless you do it as a home groan project, of which there are plenty of on the web and some with good results.

With the current advance in battery technology surely this becomes more than just feasible.

The question is: Would it not be more beneficial / economical fitting 4 pancake motors with control electronics, that will power the vehicle, be used as a braking system and regeneration of power, than fitting a singel big motor, like in the home groan project.

Thanx

Virus

Nigel Goodwin

I don't think battery technology has advanced anywhere near far enough yet?, and certainly the battery costs aren't really very feasible.

I would suggest to make it really viable it needs a 'quantum leap' in stored energy technology - probably a minimum of ten times the power/range for only a tenth of the cost - battery size/weight dropping to a tenth would be a good idea as well. Needless to say it should also be reliable, and have a good live expectancy. But currently petrol is so much more efficient at storing energy.

I would also suggest that converting existing vehicles isn't a good idea either, they are far too heavy - you need a chassis/body specifically designed for the vehicle, made from modern hi-tech low weight materials (carbon fibre being one obvous choice).

But 'pancake' motors may well be a good idea, but again it's more new design than conversion.

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Virus

Nigel

Ok just to put some weight behind my thoughts.

Have any one watched the movie “How killed the electric car “ ?, I think it is a must for every road user.
At this site you can watch snippets of the movie.
http://www.sonyclassics.com/whokilledtheelectriccar/

Some revues and critiques http://www.rottentomatoes.com/m/who_..._electric_car/

If you can get the movie, special the part where Alan Cocconi mentioned that his T-zero can do 300 miles on 1 charge at 70 miles an hour using only 6800 commercially available laptop lithium batteries.

If they replaced these batteries into the EV1, the batteries would outlast the car itself.

Go to the Tesla car site and see how big the power pack on that car is, compared to the performance spec. This is not what I am suggesting a high power performance vehicle.

http://www.teslamotors.com/design/under_the_skin.php
The motor only weighs 70 pounds.

With even half of their spec you should be able to get a viable alternative for a normal commuter vehicle.

Virus

Nigel Goodwin

I wouldn't use 'only' and '6800' in the same sentence!

Assuming only $50 each, that would be $340,000.

I would also presume the claimed 300 miles at 70mph is on a track, and not general road use? - where it would most probably be a much shorter range? - but to be fair conventional cars are often specced in a similar way.

I'm not trying to be negative, I just think that the required technology is a fair way in the future yet! - other concerns are obviously lights and heater/air-con - both of which would add additional loading.

What you need is a 'Shipstone' - for those who read one of my favourite authors!

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audioguru

A company makes an electric car in Quebec, Canada. It is powered from two 12V batteries, seats two people, has a top speed of 35mph and a range of 80 miles. It is too small and slow to be licenced in Canada but it is sold elsewhere. I think it is just an expensive golf cart.

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Uncle $crooge

Virus

Just to feed your eye on.

T’zero
http://www.acpropulsion.com/tzero/lithium-ion.htm

Mini
http://www.pmlflightlink.com/archive/news_mini.html

Virus

Virus

Just to feed your eyes on.

T’zero
http://www.acpropulsion.com/tzero/lithium-ion.htm[/url]

Mini
http://www.pmlflightlink.com/archive/news_mini.html[/url]
http://www.pmlflightlink.com/[/url]
http://www.pmlflightlink.com/motors/hipa_faq.html

Virus

Audio
How dificult can it be to build/modify a system to work ?

Virus

Just to feed your eyes on.

T’zero
http://www.acpropulsion.com/tzero/lithium-ion.htm[/url]

Mini
http://www.pmlflightlink.com/archive/news_mini.html[/url]
http://www.pmlflightlink.com/

Virus

Audio
How dificult can it be to build/modify a system to work ?

audioguru

How many experienced engineers worked full-time and how many millions of dollars were spent to produce the prototype car?

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Uncle $crooge

Nigel Goodwin

I think they had one on Top Gear tonight (the 2007 series finale), they drag raced it against a Mustang!

They then radio controlled it, put wider wheels on, and filled it full of more batteries - it then (supposedly) beat the Mustang. I won't spoil the rest of you, except it was voted the worst 'car' of all time!.

__________________
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Super_voip

The t'zero looks like it has come to an end, only 3 made and the last one was 6 years ago. Even the website isn't being updated.

Virus

YE

Pity about the Tzero, (they don’t make Tzero’s any more . . ., but why just can a good concept, why can’t you and I build our own, does it have to be al glamour’s and Hi-tech. ) but if one look at the AC propulsion site, that technology (electronics, etc.), was used in the EV1, is now used in the Tesla car and others. etc.

http://www.acpropulsion.com/vehicles/others.htm

The PML company calls them self’s “ innovators “, maybe 10 years from now we will one day say, “ yep, we thought about it once.”

Maybe they (PML) will think of making a general DIY kit product for the general public. That can be fitted to most cars, not with the spectacular specs as a Tesla or T’zero or their Mini.

For a year and a half now I am following a bunch of guys trying to replicate a Steven Mark’s Power TPU, these guys just dug in, and believed that it can work and with some success. Well suppose they get it to work, everybody that said they were nut’s, will have a different song to sing. Which is more feasible, build a TPU and wish it would work or build on current proven technology.

And Guy’s hope you and the family al have a blessed Christmas, well a quite one is also OK.

Have a blessed season.

Virus

Oznog

Well, specifically what you asked about was using the brakes to power a generator when stopping the car. This is called regenerative braking. It substantially improves range during in-town start-stop driving, but is of no use on the highway. Be aware that aero drag gets more and more substantial and that's the enemy in average driving more than the energy lost in braking. They don't use separate motors. The drive motor acts as a generator when stopping. The Prius does it already. AFAIK all hybrids and serious tech electric cars do it already.

It is problematic in that the power surge is large- and many batt technology simply cannot accept say a 300 amp charging current! For example, lead-acid batts, you put the maximum 14.6V on a partially discharged 100AH batt and it may draw 75amps. You let the voltage rise to 19V to try to force 300A into it and it'll boil off water rapidly into hydrogen and oxygen, create an explosion hazard and the battery will need to be topped off later, but probably won't actually make the batt charge any faster.

So there are limits to how hard you can use the regen braking, more than the batts can take will have to be burned off in a large resistor or just use normal brake pads to stop the vehicle faster.

4 "pancake" motors are not inherently more or less efficient. A simple big DC motor capable of quite a few HP at 90% efficiency can already be had off-the-shelf at a reasonable price. So there's not a HUGE amount of gain possible here. The gains to be made are in storage capacity.

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I thought what I'd do was I'd pretend I was one of those deaf-mutes.

Oznog

EVs are NOT slow. Right now amateurs are building EVs with quality lead-acid batts and they accelerate quite fast. Might only get 20 mile range for a simple design, others who know what they're doing can get a good bit more.

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I thought what I'd do was I'd pretend I was one of those deaf-mutes.

Oznog

Sadly, no. Lithum batts may brag about being able to recharge many hundreds or thousands of times, but the real problem is that they have a limited calendar life. Several years at best and they lose much of their charge capacity, regardless of whether they're cycled or not! This is the beast that haunts the designer. Even the large cells designed for EV prototypes face this problem. Some technologies claim to be able to achieve a far longer calendar life but it's not clear whether it will actually make it to market and it will take a few years to even verify the claims in the field.

Having many small cells presents enormous charge balancing issues that are almost insurmountable for normal use. Failure to exactly manage charge in lithium batts will rapidly degrade them at best and at worst will cause a fire.

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I thought what I'd do was I'd pretend I was one of those deaf-mutes.