# Building from the ground up.....



## david85 (Nov 12, 2007)

I am still a newbie here, so please be gentile, I hope this is the correct forum for this discussion.

I am planning to build an electric car from the ground up, the idea is to combine as much of the best technology as possible and I'm hoping to get some imput, ideas, or just opinions. The idea is to sell these cars, if the prototype is a success, and there is interest in it.

The solectria sunrise seems to be the closest example of what I have in mind, and if it ever becomes available as a glider, I would definately consider using it as the platform.

Structure

I want this car to be as light as possible, so composite is the preffered material. For cost reasons, carbon fiber will not likely be used for the entire structure, but instead will be used in structurally stressed areas (its my understanding that the sunrise was built with this in mind), although if cost permits, I will use more carbon and kevlar. I also will try as much as possible to use foam core double wall construction. The idea is to use high impact foam in areas like doors, pillars, fenders, and bumpers to act as impact protection, foam has a unique ability to absorb energy in a controlled and consistent manner, but it will also keep wind noise down (engine noise will not be a problem ). I am also considering adapting a mustang fastback replica f/g body to custom chasis, I thought of using a kitcar body, but I am after a four seat car with a hard top. I want opinions here, would you rather have, classic muscle car, or arodynamic cruiser?

Drive system

My first choice would be a wheel motor setup, and there are a few available out there. Some use an integrated planetary, while others can perform well with zero gearing. Since I am after as long a range as possible, efficiency is the first priority, so I figure a 3ph AC system is best. DC brushless is also good, but I am conserned about having expencive and powerfull magnets in the wheels which are likely to get knocked around once in a while, and AC motors tend to be less costly to build. Wheel motors would easily make the car Awd with effective regen braking as well.

Second choice would be a central motor either at the front or rear of the car, or even both ends, at the expence of weight and potential battery storage, what would you folks figure? front, rear, or all wheel drive (with awd sacrificing some range)? I am in canada, so cold weather operation will be a factor. I'm leaning more towards an AC motor here too, while a DC brished motor will be much cheaper to buy, AC has a wider RPM range, higher efficiency, and is easier to operate with regenerative braking.

The transmission would probably be a fixed ratio in the case of a central motor, since this car will not be built for much faster than 80 MPH. However I want this car to have power to spare for those who want to keep up with traffic. A central motor will also mean moving parts like CV shafts, so this is not something I like, but for now I won't rule anything out.

Suspension

Since this car will not be built to compete with the tesla roaster, I fugure 4 wheel McPherson suspension is the best choice, since it give satisfactory handling, while at the same time spares as much interior space as possible. Front and rear components, as well as side to side components will be made interchangable as much as possible. I am toying with the idea of using an air ride suspension, since there isn't much weight penalty, and it would offer a ride quality to match the quietness of the car, but it also gives a certain tunability as well. Since this is pure electric car, 50/50 front to rear weight distribution seems like a good idea, and I will aim for that.

Steering

Not much here, but I am wondering if I should bother with powersteering, since the car will hopefully weigh 2000lbs or less, and range is the priority here.

Batteries

Hmmm....Well, there are some choices these days. Lead acid is not my first one, and frankly, I would not like using them. 

Nickel cadmium are still kicking around, but overall are just not good enough to justify the cost, weight, and relatively short life.

Nickel Hydrides are better, but they could be difficult to get, and again are rather heavy for their energy strorage. BUT, they do have fairly a good track record powering the OEM Rav4s, so I would consider using them (assuming a supplier will actually sell them).

Lithium Ion seems to be the one invention of our time that could kill off crude oil AND the hydrogen fuel cell, and there are many variants to choose from, although, not all of them are actually available to some one like me.

The first gen lithuim batteries are a safety consern for me, and also have a short calender life, so I will preffer to avoid tesla motor's solution.

Lithium Iron Phosphate seem to hold promise for safety, price, and cycle life, but can ThunderSky be trusted? If any of you have had used these batteries, please share your experience, because as it is right now, they seem to be the best bang for buck in terms of performance and cost.

Electrovaya is a canadian company that has made its living on notebook computers and batteries for them, but has also pioneered a "super polymer" battery, which they deployed in a converted vatara. They claim to have broken the 300wh/Kg barrier, and are still making improvements. Unfortunately, I can't get a reply to any of my Email inquiries, and thus far cannot make a fair assessment of how siutable this battery may be, but if you believe their claims, it can deliver everything from hard accelleration, to cold weather operation, to the holy grail of the electric car, *LONG RANGE!!*

Lithium sulphur is one of my personal favorites, because they have achieved an impressive energy dencity as well, and unlike electrovaya, they do answer Email inquiries, even if their technology is 5 years away, and has been for a while now, hmm......we shall have to see. They claim to be at the 350Wh/Kg mark now, and are within reach of 600 in the "near furure", but 300 cycles are as much as they are willing to claim.

The nannosafe battery is also a good performer, how can you argue with 15 000 100% DOD cycles? (with only a 15% capacity loss) But as with other pioneers, they don't seem to be too keen on dealing with small fry like me, but if I can ever get a price, and (heres some REAL wishfull thinking) if its reasonable, then I would definately consider using them. Being able to offer an unlimited distance 15 year waranty has a certain ring to it. After all, electric cars are more reliable than ICE powered cars.

Final thoughts

Well, first of all, sorry for the long post.

The overall idea here is not to build a car as cheap as possible, but to make something that can fill the gap between the testa, and the low speed NEVs that like to tie up traffic. But more importantly, to remove the last remaining stigma that electric cars have, limited range.

Time will tell if I can ever do anything about this, but for now I'd like to know what you all think.


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## david85 (Nov 12, 2007)

Hmm....23 views and zero replies, did I go too far???

The idea here is to start a discussion on what we hope for in an electric car, surely some one has something to add here.


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## pandaran (Nov 13, 2007)

I'm still in the research phase, so I don't have much to add to all of this yet, but it's nice to see some opinions and comparisons on different battery types. 
My chief concern at the moment _is_ the money factor. Gas prices are going up and up, and it makes me angry that I am being forced to pay for them when there are viable alternatives that should cost less.
However, it's really exciting to see someone doing research into improved range! At some point in the future I would definitely like to go entirely EV (unless an even better alternative pops up in the meantime). I'm very interested if you could post information on the price ranges for the different battery chemistries whenever these companies get around to responding to you! Maybe you could even put it in the wiki.


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## Mr. Sharkey (Jul 26, 2007)

david85 said:


> Hmm....23 views and zero replies, did I go too far???


Um, well, we're kind of overwhelmed thinking about building from the ground up. Maybe the forum needs a new section: DIY Electric Car Factory!


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## david85 (Nov 12, 2007)

Thats what I was afraid of. What I put fourth is my interpratation of the ideal electric car, and some ideas to make it possible. But that doesn't mean we can't discuss more basic aspects of the idea by themselves. 

The idea here is to further the knowlage of the technology, and in that respect, I think everyone here can contribute, even if its just to comment on the idea.

pandaran,

I have been in the reasearch phase off and on for the last 8 years, and I still have a lot to figure out, for now this is just a side project of mine, but I am begining to see the potential for something real here (technology as well as market acceptance). Cost is big obstacle for me too, but for now my car is just an idea.

If I can help with your project (or anyone else who is whatching) by sharing my reasearch, I will post more detailed info here on some of the technology I have mentioned as time permits.

Should I start with batteries first? Range seems to be the most consistent problem with electric cars. 




(I will also bring ICE powered range extenders into the topic later on if thats OK with everyone)


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## Greenflight (Sep 13, 2007)

Check out www.rqriley.com, if you haven't already. They sell plans for a bunch of cool DIY cars and stuff. Most of them have foam core/fg/cf bodies (I definitely think that's the way to go for a custom car). You might get a few construction ideas looking at them. And BTW, go for aerodynamic cruiser. Muscle cars are cool as classics, but that's a little too retro for my taste!  

I'm thinking power steering is kinda pointless for a car in this size range... Maybe some kind of variable ratio manual steering?

And yeah, definitely keep us posted on what you find out as far as battery pricing. We're all waiting with bated breath.

Good luck. Not a lot of folks have built custom electrics. It'll be interesting to see what you come up with!


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## pandaran (Nov 13, 2007)

david85 said:


> (I will also bring ICE powered range extenders into the topic later on if thats OK with everyone)


If you're talking about PHEVs, I'm very interested in that! For my first conversion I'm going to keep it as cheap and simple as I possibly can, since I have no mechanical background and very little electric (I know! What am I getting into?!), but the idea of an electric car with possibly diesel or biodiesel as a backup is intriguing. I've seen a little bit about it, but haven't had the time to read the articles or blogs in depth.


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## EricN (Oct 18, 2007)

I am currently in the middle of building a replica of a GT40 from scratch. I spent years designing the frame in AutoCad, I have spent $$$$ on engine and transmission parts and put many hours into building the molds for the body. I will tell you the one thing you are going to run into trouble with. By the time you get anywhere, something new is going to come out and you are going to change your original design and go with it. This will happen over and over again. Unless you find a semi-built kit car to work with or something that is able to take hundreds of hours of work out of the solution, your technology will be out of date before the car even looks like a car and there is no way to design for what has yet to be discovered. Unless you somehow have a way of building it really quick, you might find it a project that never gets anywhere.


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## zibko (Nov 9, 2007)

Thanks for sharing your dream list David. Why to try reinventing the wheel? Most of cars these days are nice already. Variety is here and everyone can find something to suit needs or budget at the moment of purchase. The only part we do not like is IC engine. 
What is the point of building whole car from scratch anyway? There are few corporations on the planet doing that for decades. Let’s concentrate instead on what they can not or don't want to do so far - long range EV.


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## david85 (Nov 12, 2007)

*Greenflight,*

thanks for posting that link. In fact I have seen that website before, and while I am not a fan of 3 wheelers, their XR-3 hybrid is an impressive car none the less, and I recomend anyone interested in this topic check out that website.

Some basics about the XR-3

Air bag suspension, and I think it is Awd (2 front wheels are diesel, single rear is electric)

foam/composite construction, mainly hand carved (eeeeek, lots of messy work) ontop of of a steel "tunnel" frame (extremely strong, but still very light).

Diesel engine in the front, and electric powertrain in the back (this is a parrallel plug-in electric hybrid)

1300 lbs curb weight (very nice)

125 MPG with diesel power alone, up to 225 with mixed diesel electric driving (this is their claim, so I take it with a grain of salt, but I think its possible)

If this car had 4 wheels, I would consider buying one, but I might just steal some of their ideas instead.

Here is some info on the diesel engine that is recomended http://www.dieselenginemotor.com/kubota/supermini/page5.html. But I can't help but wonder why not use a VW diesel, it would have to be much cheaper and get at least as good economy (and more power).

*panraran,*

I'll just go over some of the basics first.

There are two basic types of hybrids (in theory, either one could be a plug in): 

The most comon is parrallel, this is what the prius and insight use. Usually, it is an adaptation of a conventional powertrain, such as the addition of an electric motor/generator to an automatic transmission that can give what the industry calls "launch assist" as well as some regenerative braking. This setup rarely results large improvements in fuel economy, because all of the same moving parts that the car would normally have are still there, like the automatic transmission, and in the case of the prius, the electrics basically do nothing once on the highway (this is why the WV TDIs get better MPGs). By toyota's example our 1956 fergason tractor is a hybrid, becuase it can propel itself a few feet with the starter (no neutral safety switch).

The other kind is the series hybrid, the chevy volt is supposed to a series hybrid (I'll believe it when I see it, after seeing what GM did to the EV1). A series hybrid is basically an all electric car that has a genset built into it. This has the advantage of getting rid of many of the heavy moving parts of a parrallel hybrid (transmission, driveshaft, and possibly even the differential). In this configuration, the batteries are always powering the electric motor, which is always driving the car by itself. When the battery runs low, the generator kicks in and keeps you going. This allows you to get away with a smaller (hopefully more economical) ICE to run the generator, which no longer has to propel the car up steep inclines or up to speed at the onramp. In theory, this car can also double as a backup generator for your house. I preffer series .

A simple way to think of the difference betwwen series and parallel, is that series is based on a pure electric car, a series is based on a ICE powered car.

In theory, any electric car can be converted to series hybrid, the trick is finding a powerpland compact enough that can still meet the cars average Hp requirements.

*EricN,*

I would be very interested in learning more about your project. I have some experience with polyester and glass fiber, but never tried something as big as this before. How did you get the shape? the GT40 is not an easy shape to make from scratch.


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## david85 (Nov 12, 2007)

zibko said:


> Thanks for sharing your dream list David. Why to try reinventing the wheel? Most of cars these days are nice already. Variety is here and everyone can find something to suit needs or budget at the moment of purchase. The only part we do not like is IC engine.
> What is the point of building whole car from scratch anyway? There are few corporations on the planet doing that for decades. Let’s concentrate instead on what they can not or don't want to do so far - long range EV.


Most cars are heavy being made out of steel, which will kill some range no matter what battery is used, so even with the best batery, overall performance will still be better with a lighter platform. I'm shooting for the moon here, but time will tell if its actually possible in the end. 

Oh, and I can't stand rust, since it does rain a lot where I live.


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## EricN (Oct 18, 2007)

david85 said:


> *EricN,*
> 
> I would be very interested in learning more about your project. I have some experience with polyester and glass fiber, but never tried something as big as this before. How did you get the shape? the GT40 is not an easy shape to make from scratch.


I pulled molds off of a body. I will tell you right now if you are planning on building your own body it better be so you can sell it because to make the molds is about 4 times the cost of actually buying a body already done, plus you have to deal with storing them. I was lucky because I had the help of a buddy who owns a fibreglass shop who is also wanting to build one and maybe sell too so the mold was a viable option. Also, the mold took a year from prep of the body to copy all the way to actually making a mold. Now the molds still need to be prepped and ready to actually use, probably another 6 months. It would definately be better to find a kit car and modify it, but if you have the ability and time, start from scratch, that is what I did,,,,, 6 years ago.


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## david85 (Nov 12, 2007)

EricN said:


> I pulled molds off of a body. I will tell you right now if you are planning on building your own body it better be so you can sell it because to make the molds is about 4 times the cost of actually buying a body already done, plus you have to deal with storing them. I was lucky because I had the help of a buddy who owns a fibreglass shop who is also wanting to build one and maybe sell too so the mold was a viable option. Also, the mold took a year from prep of the body to copy all the way to actually making a mold. Now the molds still need to be prepped and ready to actually use, probably another 6 months. It would definately be better to find a kit car and modify it, but if you have the ability and time, start from scratch, that is what I did,,,,, 6 years ago.


Very VERY, interesting, as it so happens, I was considereing using a GT40 (kit) at one time, the original location of the large fuel tanks on both sides make it a tempting conversion platform (and thats before you consider the space where the V8 and tranny normally go) due to the potential space for batteries. But getting replies to my inquiries proved difficult. I would be very interested to see how it turns out.


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## pandaran (Nov 13, 2007)

david85 said:


> *panraran,*
> 
> I'll just go over some of the basics first [...]
> 
> A simple way to think of the difference betwwen series and parallel, is that series is based on a pure electric car, a series is based on a ICE powered car.


Series is definitely what I'd be interested in in the long run. It makes me feel safer. I'd hate to think of running out of "fuel" out in the country somewhere with an EV! Especially since they take so long to charge! (I wonder how the Tesla charges so much faster than the other cars Rob posted in his blog, when it uses the same type of batteries. http://www.diyelectriccar.com/blogs/2007/11/six-major-preproduction-electric-vehicles-compared.html)

Have you seen the drop in kits that convert the Prius to optional electric drive? http://www.electric-cars-are-for-girls.com/plug-in-hybrids.html
Waaay out of my price range, though.


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## Greenflight (Sep 13, 2007)

Not to go off topic, but an interesting note about the Prius is that it's sold in Europe with an EV mode. i.e., you can press a button and the car will operate purely off the batteries, without running the engine. It's got a very short range, but can be used to avoid starting the engine just to move the car across the street.

In the US, the car is sold with the full capability of using EV mode, only without the button. So all you have to do is populate an empty cavity in one of the ECM connectors, and run it to a switch on the dash, and run the other side to ground. Voila, an electric car with a one mile range. There's about a million articles on the web that show exactly how to do this.

Now, I'm guessing that once this is done (cost: $4?) it's a simple matter to add a few batteries (maybe 8 or so lead acid, figure around $700) and a charger (maybe $400 or more, depending on what you use) and probably voltage and amp gauges ($100?) and this should provide an adequate plug-in hybrid. The range probably wouldn't be outstanding, maybe 10 or 20 miles depending on how many batteries were used, but this is plenty to cut down on gas costs for a lot of people! As long as you keep the voltage similar (parallel the new pack with the old, or something like that) the car should be able to handle it OK. So, you should be able to convert the Prius to a PHEV for around $1300 or so. Or at least, having never done it myself, that's my guess.  

Okay, I'm done, back to topic.


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## mattW (Sep 14, 2007)

Only problem is they run at 288V I think, so thats 24 batteries, then you have to work out which string is going to give you more current (because the existing pack has barely any Ah so you want most of it coming out the lead ones, i don't know exactly how it works but its to do with the internal resistance). Apparently the 1st gen prius is experiencing some reports of battery failure (10 years old). You could just buy one of those dead ones for cheap and completely replace the battery pack with good old lead at a much higher capacity. That would be much cheaper and easier than trying to match a tiny Lithium pack to a giant lead one.


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## pandaran (Nov 13, 2007)

So people are giving up on them and selling them for cheap just because the battery got old?  That's one of the weirder things I've heard lately.


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## david85 (Nov 12, 2007)

There are many other options other than just lead acid battereies. I have seen several examples of prius conversions, one that comes to mind is one I saw on the evening news. They were able to access the OEM NiMh batteries an that is what they fitted to the upgraded prius, but ofcourse it was not cheap. The car had a range of ~30miles and a limited top speed in all electric mode (still fast enough for city driving).

Apearently its possible to get a conversion kit for the Rav4 as well, you have to admit, it is at least a little ironic. since toyota stopped offering their own EV Rav4 (although toyota did not have much of a choice, leagally).

pandaran, about your comment about there being more than just one type of lithium batteries....

From what I have seen, there are about a dozen different chemisties, that are under active developement, or already in use, its basically an arms race for the ultimate battery. Each one of them having their own unique advantages, and not all of them are restricted from the general public.



......This does bring cost into the picture though, thundersky batteries are available to anyone who wants them (lithium iron phosphate), and volume discounts are up to 40%, but it remains to be seen how reliable they are.

I'd like some opinions here, what is more important to the rest of you, affordability, or performance and long range? (within reason, ofcourse)


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## pandaran (Nov 13, 2007)

Will I get smacked if I say both? 

Affordability is important to me, but if the battery's life made it more affordable over an extended period of time, as opposed to replacing the cheap ones more frequently, I'd be willing to fork out a little more at the beginning. Especially if it would get me longer range, too!


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## houseoffubar (Nov 18, 2007)

pandaran said:


> Series is definitely what I'd be interested in in the long run. It makes me feel safer. I'd hate to think of running out of "fuel" out in the country somewhere with an EV! Especially since they take so long to charge! (I wonder how the Tesla charges so much faster than the other cars Rob posted in his blog, when it uses the same type of batteries. http://www.diyelectriccar.com/blogs/2007/11/six-major-preproduction-electric-vehicles-compared.html)
> 
> Have you seen the drop in kits that convert the Prius to optional electric drive? http://www.electric-cars-are-for-girls.com/plug-in-hybrids.html
> Waaay out of my price range, though.


 I suspect that despite the chart showing 110volt charging that the 3.5 hour time for the Tesla it is actually 220v. The Tesla holds significant amounts of energy, that is simply not possible to charge that fast using a 15 or 20 amp 110v outlet


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## david85 (Nov 12, 2007)

No, that doesn't quite qualify for a smack, I'd preffer getting it all as well.

There are compramises in battery chemistry, and more expencive batteries can deliver better life,

But this really comes down to bit of a dilema with getting an electric car. EVs can easily outlive most any other ICE powered cars, but despite being simpler, and having fewer moving parts, the purchace price is still higher. This is why I went all out with the idea of building an electric car, since making one cheap enough to compete with a civic is just not realistic, I may as well build one to last (or at least try).

Lithuim cells have come a long way in the last few years, but frankly, its too soon to tell how long many of them can live, because in most cases, they are still within the theorietical shelf life.

But this is an interesting read: http://www.lionev.com/Battery_Pricing.html

If you havent heard of LoinEV.com yet, they are aiming to convert the hyndai santa fe, accent, and ford ranger to electric for sale to the general public, but they will also sell battereies (and BMS) to anyone whoe wants them (minimum order is 10KwH). They are still quite new, and it remains to be seen how succesfull they really are, but I sure hope they can pull it off.

They are one of the few sources of prices on advanced battereies, and you can see the difference between low purchace price vs high performance and long life (if you navigate the website, you will find well detailed price lists on differend chemistries, and systems)

These guys are also pushing the limit in warantee as well, the two high end batteries are offered with a 7 year coverage, or lifetime coverage if you buy the BMS (battery management system) as well. In the case of lifetime warantee, it qualifies for replacement when the cells can no longer return 50% of rated capacity.

Personally I would be tempted to go with the high end battery, even though it could cost $30k and up, but thats just me. Although I would probably go off the deep end, and try to fit a 100Kwh pack in the car (in theory, that could mean a 1000 mile range, you don't want to know how much a 100Kwh pack would cost though).


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## pandaran (Nov 13, 2007)

XD Woo! 1000 mile range? I love it!! 

So, $373 per KWh is the cheapest lithium battery pack on the market according to them. That means if my hypothetical car weighs 1000kg, then I'd get a little over 3 miles from one battery pack. Is that right? And then you have to add in the weight from the batteries, motor, and whatnot, too, right? (So many numbers to take into consideration! My brain hurts!)


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## david85 (Nov 12, 2007)

The distance you can travel is based on many factors (weight and drag mainly), but it is possible to estimate by calculation.

Using your example, it would mean a distance of 3 miles per kwh of energy consumed. In the case of the solectria sunrise, it was equipped with a battery pack that could store up to 21 kwh's of energy, so 21 kwh x 3 miles per kwh = 63 miles of range of that example. (lionev's minimum order size is 10 kwh)

In reality though, the sunrise was documented returning a range of 375 miles under favorable conditions, but If I were to take this and run with it, we could get a range of 1780 miles with a 100 kwh pack (if we assume that it can deliver 17.8 miles per kwh of energy, and that the car weighs the same).

Now for the reality check. 

The solectria sunrise was a light (for an EV) and arodynamic car, and under more realistic urban traffic conditions, 300 miles of usable range was also observed. At 60 MPH, the range was reduced to 200 miles. Heres some more info in the sunrise: http://en.wikipedia.org/wiki/Solectria_Sunrise If anyone else has some info on this car, please chime in.

Weight of all those batteries are also of some consern, as the heavier the car gets, the less miles per kwh's (MPKs) it returnes (same applies for higher speed), simply fitting them all in could also be a challenge. But this is where it comes back to energy density of the battery itself, since we are getting close to having batteries that allow us to have our cake, and eat it too.

In the case of the lithium sulfur battery shown here: http://sionpower.com/technology.html

A 100kwh battery would only weigh approximately 286 Kg or about 630 pounds, and we still have to consider the wieght of the battery case(s), wiring and electronics. (Sion battery = 350 wh/kg)

But with such a long range, why would anyone really need more than 300 100% discharge cycles (theorietical service life of this example would be half a million miles)?

And before you ask, I have no idea what the projected price of sion's lithium battery will be if it ever gos into mass production, but its still nice if we dare to dream sometimes....


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## david85 (Nov 12, 2007)

*I have some updates to report.*

I have been in contact with a lithium polymer battery builder for the last week. Their product is the same one that was used in the Impreeza EV race car mentioned on annother thread.

Kokam (korea) is the authorized manufacturer of these cells (older, cheaper LIon are also available), and *they will sell to the general public.* Some of you may be aware that kokam is already well know as a supplier of lipo cells for high performance RC batteries. (If you see an electric RC plane climb strait up like a rocket, chances are it is powered by kokam cells)

The cost is still not very good compared to lead, but lithium polymer batteries could yield a lifespan of up to 10 years, and they are zero maintainence. The cost, as verified from two sources is at U$1600/kwh.

To give a basic picture of what that would be for a real car, the sunrise had a battery of 21kwh, so $1600x22= $33600. Not cheap I know, but the sunrise had a range of over 300 miles as documented on several ocasions (with heavier batteries) if the size of the battery would be scaled down to the size that most conversions have, the cost would be more comparable. BMS is extra. The estimated weight of such a battery would be 126 Kg or 276 lbs (again, BMS would raise that slightly).

In addition, the cost of the battery continues to come down, and discounts are available for high volume purchaces, I have yet to verify how much these discounts are, but as some one from ProEV.com told me via Email, the more you get, the better the price. There has already been a cooperative purchace of thundersky batteries, and this could be a way to get these at a lower price.


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## RevDon (Nov 21, 2007)

Falcon EV is now selling wheelmotors! Take a look, they'll give you something to think about

http://www.falconev.com/


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## david85 (Nov 12, 2007)

Could be promising, so far most wheel motor builders seem to think that they are worth their weight in gold, and once again the chinese save the day. I'll have to keep an eye on this, maybe they can be ordered in a larger size, I've got to find some specs on these things........


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## gregb (Dec 3, 2007)

Hello first post,

So with the talk on battery power and weight, can we calculate what the weight to power is of batteries commonly used for ev's and compare it with the weight to power of the lithium batteries? Then do a cost comparison to figure what will be the better buy.

I expect either there is a chart somewhere (which would help me look at battery comparison) or this question will be overlooked.

Love the forums


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## david85 (Nov 12, 2007)

gregb, welcome to the forum, I've only been here for about a month myself.

There are many charts out there on the internet, but I stopped paying attention to them a couple of years ago, things are moving too fast for such info to stay current.

The standard for costing a battery is typically in terms of $/wh, watt hours being the measure of the energy storage potential

To get the $/wh rating of a battery you really have to get prices from the battery supplier directly, which is not a problem with lead acid, since they are available at the retail level all over the place. Getting prices for nickel, lithium or other more advanced batteries can be challenging though, since many of them are still at the development stage, and most would rather not reveal their prices to some one other than a mega automaker.

And then it gets more complicated when volume pricing comes into the picture. I suspect lead acid is still the cheapest of them unfortunately, if purchace price is your main consern.

The only prices that I have been able to verify so far, are related to lithium batteries, since they are my personal favorate for this project (hence thats what gets most of research focus). I'll post what I can for now

Kokam/worley cells:

Energy density: 160 wh/kg (varries by cell application)

*Cost: $1.60/wh* (this is for lithium polymer, not the older lithium ion)

cycle life: 800-1200 @ 80% DOD

calender life: ~10 years (no proven tests, just the claim (expect a minimum of 5 years)

a123 Lithium Iron Phosphate spiral cells:

Energy density: 108 wh/kg

*cost: : ~$0.85/wh*

cycle life : over 1000 @ 100% DOD

callender life : unknown, lithium iron phpsphate is only a few years old, but it should perform better than the older lipos

There are many other factors to consider, but these are the ones you want to look at when figuring out overall cost of ownership. hope that helps.

If some one else wants to chime in with some data from their EV, please feel free to do so, prahaps we can compile the data later on a different thread.


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## david85 (Nov 12, 2007)

Chiba, Japan? wow, this *is* a global forum!

The nanosafe batteries are similar in energy density to NiMh, according to altair's claims. This page shows the performance graph: http://www.altairnano.com/markets_amps.html

You are correct that phoenix motor cars is using these batteries, and more recently, these guys in the UK have jumped in too. http://www.lightningcarcompany.com/

The lightning car has the potential to set a new standard in every way imaginable, by using PML's wheelmotor (Hi-Pa drive) powertrain, the car will possibly have the best overall performance in terms of traction as well as accelleration and braking.

And then there's the eliica supercar, I'm betting you have heard of it.......(don't think they are using the nanosafe battery, but it is still direct drive with lithium batteries)

But as far as altairnano's batteries go, I can't find much in the way of pricing or even projected long term cost. The best estimates I have seen so far are purely speculative and assumes that the technology will be heavily subsidized. The cost for the battery pack per truck is thought to be somewhere between $40k and $80k USD. Its not out of line if the cost can be driven down, this is still a very new battery after all.

EDIT: PS, I don't even know if they will sell them to end customers.


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## david85 (Nov 12, 2007)

If you don't mind my asking, where are you getting your hub motors? I have had a helluva time trying to contact potential suppliers of suitable motors, PML Flightlink was so far the only one that took us seriously, but the cost was just too high for this application(~90K USD).


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## david85 (Nov 12, 2007)

PML has revealed agreements with lightning and volvo after we contacted them, so it doesn't suprise me that they are less open now, I doubt I would get a reply again. BluWav is annother company that has a good product (USA), although they use an integrated planetary to step up the motor torque. Its a nice little package, and includes a disc brake, and the back of the motor is already designed to accomodate ball joints, so it would be easy to mount on just about any car, but they too don't seem interested in answering inquiries. But if your just still looking, you might find this usefull.

http://www.wavecrestlabs.com/products-motors.php

Even here in canada there is a wheel motor company (TM4), but they were almost annoyed with me for inquiring.

Its getting to the point that I will either have to consider goint to a central motor (like the tesla), or designing my own wheel motor. I don't quite understand what the big deal is, its not like hub motors are a new idea.

Asside from the shape, liquid cooling seems to be the key to getting large amounts of torque out of a relatively small package (along with different internals to favor lower RPMs).


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## david85 (Nov 12, 2007)

Lexus said:


> Interesting Read on there Motors
> 
> Features, Functions and Benefits : (Four motors on a 3,000 lb vehicle)
> Acceleration performance: 0-60 mph in 5.0 sec
> ...


Haha, yeah thats pretty much what they told me when I contacted them, and they got sturn when I tried to explain that this was not going to be a one off, and then they sent us PML's web address oh well.....(google wheel motor and TM4 are usually first on the list)

But about the bluwav motor, while the max output is lower than say the Hi-pa drive (45kw vs 120), the gradability is MUCH better than any hub motor configuration that I have seen thus far. PML quoted us on a motor that was only rated for 14% grade. I wonder if it might even be possible to build a off road rock crawler with bluwav's design with so much torque available.

I have a feeling that the eliica may have a similar vulnerability. I observed a drag race between it and a gasser (long live Utube!), and the gasser had the edge off the line since it apearded to have more torque available at the wheels. But ran out of HP further down the track and was overtaken by the EV.

BluWav's claim of low cost is what makes me hopefull that I may still get though to them later on, soposedly they are in the midst of some sort of restructuring, so who knows what is going on right now.


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## david85 (Nov 12, 2007)

If you use a brushed DC motor in a 10:1 fixed gear ratio, then you might run out of RPM. A 3 ph AC motor however, will run at 9000 all day without any of the problems of brush arcing. I remember reading that the solectria "tranny" is available with a fixed ratio of as little as 5:1, which could work better for a brushed DC motor.

If you don't end up with enough accelleration, you could always put one motor at each end of the car.

As a footnote, I am almost positive that this is the powertrain that ZENN and Dynasty are using in their NEVs.


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## david85 (Nov 12, 2007)

Lexus, I hope you take this the right way, but I think you might just be as cazy as I am.

I never saw MR all the way through, so this is the first time I have ever seen this car. I find it neat that a company like lexus has to go to an independant prototyping shop to develope something as advanced as this.

Long live the CNC machine is all I can say, with a big enough machine, some urethane foam, and some imagination, the sky's the limit.

Have you decided on the type of composite yet? I can see that the lexus concept use a steel frame. Whats interesting about the eliica, is that there is still lots of room left for more batteries, I'm betting that lithium batteries are a little cheaper than when the eliica was first built. Would you happen to know the capacity of the battery they used?

If you don't mind using a current design, the UK seems to be very competitive for kitcars, and the prices tend to much lower than in the USA.

If you were to look at the ford GT40, it has lots of room for batteries in saddle position, similar to the Tzero, but there is still room behind and in front of the passenger compartment.

300k range is very reasonable, if you keep the weight down and use an aerodynamic shape. Lithium polymer batteries seem to still have the edge in terms of energy density. heck, if the sunrise could do it with Nimh batteries, the results with lithium batteries should be exellent.


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## david85 (Nov 12, 2007)

Lexus said:


> There is a Aussie back home making the GT90 all from drawings as there is now way in the world you can get your hands on the Ford GT90
> 
> 
> 
> ...


 
I tend to be old school when it comes to car shapes, but I have to say, I like what they did with the seats, unlike the norm, these have an elegant low profile to them, the narrow backrest could also spare some extra leg room if there is a back seat. nice interior overal (is that a touch screen I see?).

I'm thinking that a space frame might work for me too, but from what I have seen in F1 racing, all composite can still be very safe and strong, while at the same tme it can greatly simlpify the overall design of the vehicle. The chassis can be made in one piece now, and have all the reinforcing exactly where it has to be (as opposed to having to wield in gussets, for example).

I work with aluminium for a living right now, and its a very nice material, but I am drawn to composite becuase you don't have to cut, stretch, or wield it to get the right shape. just a thought, I have a feeling the structure will be the least of our worries though.


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## david85 (Nov 12, 2007)

What is really neat about using LCD screens is that you can change the overall feel of the interior of the car without having to hack anything. Some drivers may preffer oil pressure gauge, others are good with a warnng light, for example. Instead of just having a "check engine light", the computer can be set to alert the driver to the exact problem or condition. More information can automatically be turned on for a "sport mode". If you don't like where the climate controls are, move them.

And since everything is programable, you could design the car to automatically reset to the personal settings of different drivers, prahaps via thumb scanner, or voice activation.

It probably wouldn't cost very much either, LCD screens are much cheaper than they used to be. If you wanted, you could have touch screens across the entire dash to to control all of the car's systems.

Maybe thats all going too far, but it would be a car out of this world if high tech is what you're after. The level of integration you could put in the car is literally unlimited, and just about all of this stuff is available off the shelf (unlike hub motors ).


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## david85 (Nov 12, 2007)

Wait a minuite, IZA? why didn't I ever hear about this? I reminds me a LOT of the sunrise, and seems to emply much of the same design features, except it uses hub motors and looks better.

548km x 0.611 = 334.8 miles, so the performance is on par, but as I mentioned earlier, in this thread, range drops considerably as the speed is increaced, the sunrise was onlu good for about 200 miles (327km) at 60 mph, but thats still good enough for the real world, in my view.

Battery size was 28.8 kwh, 30 kwh seems to be the magic number, although a reduction in weight would help, 1573kg is not very light for a compact.

So what ever happened to the IZA????































What I like about the aproach that the sunrise takes, is that the structure, bellypan, and all the mounting locations and compartments can be moulded into one single piece. But space frame can be advantagous too, repairing collision ramage can be a lot simpler when you can take the body off.


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## david85 (Nov 12, 2007)

I think I'm ready to call this one. When it comes to DC permag brushless VS multi phase AC brushless, AC is the winner.

The main reason is manufacturing cost, but even efficiency seems to be comparable, operating range is better, the motor won't eat your steel tools if you take it apart (magnetic field is on only while motor is running), easier to scale up, etc, etc...

rasertech has a very nice motor design, but so far, like many others, the technology seems to still be restricted, so who knows if it will ever be available to you or me.

The small diameter is very impressive considering the max torque, as for the high horspower, I'm betting that comes from a high maximun RPM. Full load efficiency is also very good. Yes, a very nice toy....(I want it )


Heres a list of battery companies, tech, and some prices in case you haven't already found this:

http://www.plasticlabels.ca/index_files/compareEVbatteries.htm

I've got my money on thundersky for now.


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## Guest (Dec 7, 2007)

Yep the Thundersky looks good ... I like the Ultracapacitor ... Need to read up on them more but!


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## david85 (Nov 12, 2007)

I'll have to wait and see with EEstor's hypercaps. They don't even have a website up yet, and all sorts of rumors are flying around right now.

When you think about it, there is a lot of potential IF they can solve the energy density issue, But I remain skeptical, there is a disadvantage to having such a low internal resistance. I got a nasty shock from taking apart disposable cameras once, I shutter to think what a capacitor big enough to power a car would do to my hand  (not that 140-300+ volts should really be handled with bare hands).


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## david85 (Nov 12, 2007)

*I have annother battery update.*

LionEV responded to My Email enquiry. Their lead time is ~28 days, for new orders.

Heres are the highlights of their top of the line battery:

7 year waranty, extended to lifetime with their BMS installed.

$1,040.00 per kwh


The next battery down in price has a 1-5 year waranty, and is less than half the price of the top of the line, and is 25% heavier. There is an even cheaper one, but the waranty only goes up to 3 years.

The chemistry they are using are lithium polymer, and lithium iron phosphate.

Looks like these guys are for real, can't wait to hear from them come the new year. Hopefully some of their glider conversions will be on the road by then.


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## david85 (Nov 12, 2007)

Yes, they are still quite pricy, but these batteries, at least in theory, could last long enough to pay off. But the sunrise EV got close to 400 miles (on a test track at low speed) on only 22 kwh worth of battery, and it was a heavy battery.

Now if you were to actually squeeze 50 kwh worth of lithium batteries into a car like the sunrise or IZA, well, umm like you said, holy crap batman. Ive got my sights set on 1000 miles.

By contrast, the cheepest ones would only cost $18 650 for 50 kwh (plus BMS).

http://www.lionev.com/Battery_Pricing.html

Thundersky on the other hand, could be close to $10 000 for a 50 kwh pack (again, plus BMS) with the maximum volume discount (very big volume!), but now we are approaching a price that is comparable to lead acid, but at less than half the weight, and zero maintainence. All costs I listed are in US $$.

I am going out on a limb here, but I think the "battery problem" has been solved.....

http://www.thunder-sky.com/order_en.asp


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## david85 (Nov 12, 2007)

Folks in north america are spending that much for NEVs that can only go 25 mph with a range of 30 miles (if they can even get them). If mitsubishi wanted to sell those things, in this part of the world, it would probably kill off about half of the compact and subcompacts on the road.....

So this car has a motor in each wheel?


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## david85 (Nov 12, 2007)

Darn, I was already thinking of how I could tear into that car for the parts.

I think you might have the right idea for ising the solectria transaxle, it would result in less interior space, but in reality, battery size will have more to do with cost than actual room in the car. 

Have you though about using an ICE powered range extender? I have seen one example that used a sterling engine once.


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## david85 (Nov 12, 2007)

Lexus said:


> Seen ICE push Trailers for EV .... I will not touch


Uhh, yeah, diddo. What I meant was an integrated generator setup. But I forgot that japan isn't as "wide" as this continent, or australia for that matter.

Just found annother potential supplier of transaxles/motor assemblies, and they have a power edge over the solectria version (1400 lbs of torque VS 900). No idea what the cost is yet.

http://www.enovasystems.com/index.cfm?section=Products&linkID=2

Specs at the bottom of page.


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## david85 (Nov 12, 2007)

having never lived in a big city, and spending most of my driving hours(and i do mean hours!) towing above 110 kph, I can't see myself in a car like this, but I can see how there would be a place for them for short run commuting. But then again, I learned to drive in a 5000lb fullsize pickup, so maybe I am a little biased in that way.

This isn't actually my truck, but mine is basically identical to this.

http://s45.photobucket.com/albums/f88/srercrcr/Ford F150/?action=view&current=FordF15083.jpg

As a trades person, there isn't much of a choice for me as far as size goes....but I do draw the line at burning gasoline, this one is propane (I believe aussies call it gas, while americans call it LPG), and my other truck is diesel, never owned a petrol powered vehicle, so far, so far, so good. But I am thinking of converting my propane truck to plug-in hybrid....

If you are looking for electric powresteering pumps, these guys have them too, along with other components. http://www.canev.com/

As it turns out, ENOVA may be defunct, my emails bounced back as "indeliverable", and is was the same story for their distributors too. Maybe they are just having an off day....


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## pandaran (Nov 13, 2007)

*rofl* Apparently the forum won't let me stack quotes, but I love your angry emote, Lexus.

Anyway, this thread has been busy!



Lexus said:


> I am building a Replica of this ....
> 
> 
> 
> ...


I don't have a whole lot to add to what's been said, but I had to say that this car is beautiful!

The LCD touch screens sound pretty cool, but high tech displays in cars make me nervous. I think back to when I was a kid and my dad had a Lincoln with a digital display. Those things always ended up burning out, and then you were stuck with no speedometer. Not good!

In any case, I hope you guys are also adding a lojack or security system into your cost and weight calculations! o.o


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## Ioku (Sep 27, 2007)

I have been following this tread sense it started and love you idea of building a car from the ground up, I also like Lexus’s idea of building a replica Lexus 2052 Minority report was a cool movie and the 2052 is one of my favorite sci-fi cars. 
I like how you are thinking of using wheel motors I am big into awd and I think this would make for the ultimate awd system, but like you said wheel motors are expensive and hard to find, so why not just use 4 small motor and connect each one to an axel with gears. This wouldn’t be as space saving as wheel motors, but it would make for less unsprung weight and allow for gearing. I added a basic drawing of my idea.


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## dbgtwill1 (Dec 11, 2007)

have you considered hemp as a fiber replacement saw it on invent nation used with bambo to make realy strong light bikes 
luck 2 you
\dbgtwill1


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## david85 (Nov 12, 2007)

Back when PML flightlink was more open to inquiries, they filled out an application for our concept. With the car weighing 2000lbs, the 0-100 run time was 5 seconds by calculation, we requested 4 seconds or better, gradability was also dissapointing, and just climbing a ramp in a parking garage would have been a burden. 

The use of neodymium magnets in a DC brushless motor could result in higher torque at the wheel, but for all the extra cost, I am wondering if the better solution is to use a higher RPM motor and step down the speed with gears, such as what BluWav did. But for the cost of having a motor designed for an automotive application, a central motor is very tempting even if wheel motors are still my first choice.


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## rbgrn (Jul 24, 2007)

http://www.digg.com/hardware/These_Guys_are_building_Insane_Electric_Cars


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## rbgrn (Jul 24, 2007)

I posted that. It looked like one of you was planning on doing the GT90. Oops..


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## rbgrn (Jul 24, 2007)

It should be known that I enjoy promoting the work of DIY EVers


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## david85 (Nov 12, 2007)

Lexus said:


> OK ..... Just woke up and read that was like  LOL


Uhh,, yeah me too.... GT 90? compete with tesla? Well maybe, but I'm not exactly building yet, its just ideas for now, and pricing, Looooooooooottts of pricing out of components and systems.............

Lexus, I don't think you are going to need a 50kwh battery if your car is going to be super light, arodynamic, and travel at an average speed of 80 KPH. The sunrise got 200 miles at ~80 KPH with with only 22 kwh, and it was a 4 seater. These batteries are less than half the weight of lead, and that means a longer range for the same amount of energy consumed.

Also, remember that the LFP TS batteries are maintainence free, and are good for thousands of high discharge cycles. One company in the USA is offering a more expencive version of the lithium ion battery that comes with a lifetime waranty. Although for some reason, the japanese do not seem to take kindly to cars that last longer than 15 years.


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## david85 (Nov 12, 2007)

I'm still not sure what shape the car will take, but so far the responce has been very positive toward an high tech approach as opposed to a classic one, though I will admit, I am a sucker for old cars. In all honesty, I would preffer the GT40 classic, but in the end, arodynamics and outside feedback will play a bigger role, since the long term goal is to sell these things. But of course, its whats on the inside that REALLY counts.


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## david85 (Nov 12, 2007)

Well, seeing that we have passed 1500 views, I going to try and push my luck a little.....

One of the biggest problems I am facing, is what should the car look like? I'm going to start post different cars that are appealing to me, Lexus has so far contributed a lot of different ideas, and I'm going to do the same, but I'm hoping others can weigh in with their own ideas as well. This thread has moved on something that is bigger than just my car and my ideas, maybe some others who are following can share in the dream as well.

OK, heres what I've got for now.













1971 toyota celica (we had one briefly when I was really young)










Similar idea, but this is a later 1977 with striking resemblance to the mustang mach 1.










Datsun 240Z.

Both these cars cave a similar profile, and would do reasonably well in a wind tunnel (1977 celica is better for aerodynamics than 1971). They also have a low profile front grill that makes it more adaptable to electric duty.










....and this is the 1969 mustang I mentioned earlier in the thread (reproduction bodies are available for this one).


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## rbgrn (Jul 24, 2007)

Out of those 4, my vote would have to go with the 240Z.


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## david85 (Nov 12, 2007)

As I understand it, Tesla motors developed their own BMS. They have since started a division aimed at engineering battery systems for other companies (I doubt they will talk to mortals like us).

Metric Mind has a pretty good BMS though, not quite as pretty as this, but seems to show all the same info. Also comes with a PC friendly interface so you could integrate it into a more refined display.

http://www.metricmind.com/bms.htm


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## mattW (Sep 14, 2007)

Hey guys just a suggestion; if you have any new topics/questions how bout doing it in a new thread? This baby is already 9 pages and I would hate to be an eager new member having to read through it all to get to what they were interested in!


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## david85 (Nov 12, 2007)

I think you might be on to something there, matt. Lets face it, there are a lot of guts in a car!

I didn't want to start several threads all geared toward the same idea, but maybe that is a better way to go, now that its a little out of hand.

I'm neck deep in an engine overhaul right now (gotta love internal combustion), so time is tight right now, and I haven't had a chance to do as much research as I would like lately.

How would it be if I were to summarize the main points of, say

structure,

suspension,

motors,

batteries,

interior,

Range extenders/hybrid,

and use that as a heading for each part of "building from the ground up" in a separate thread? Then as more info/questions come up, each topic can be more, well, on topic.

Any thoughts or suggestions for how to set this up?


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## SkylineUSA (Dec 27, 2007)

david85 said:


> Similar idea, but this is a later 1977 with striking resemblance to the mustang mach 1.


Its a Boss 302 look I think it will be too heavy. I owned one back in the day, very nice ride.

I am looking into an Elise, since its very light, have you given an all aluminum car any thought as a platform for your car?

By the way, I have totally enjoyed your thread, tons of great info!


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## SkylineUSA (Dec 27, 2007)

Lexus said:


> Mmmm Nissan Hater here ...


I have 3 GTRs, hence the user name But, thats cool.

The wife wants me to convert one to an AWD electric, but after reading your thread, I am leaning towards the Elise.


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## david85 (Nov 12, 2007)

SkylineUSA, thanks for the comments. The skyline is not normally available in canada, so I only found out about it a few years ago, and more recently an importer has started to bring them in from japan. Its an unassuming car at a first glance, but has some frightening potential for horsepower. No doubt lots of local cops are getting anxious with the kind of upgrades they often come with.....

As for the elise, I'm pretty sure the tesla roadster is loosely based on it, sharing the same aluminuim monocock chassis, but having its own skin (although you can see similar curves in both cars). I'm hoping to go fully composite for my car.


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## John (Sep 11, 2007)

Building a car from scratch as an EV is a tremendous opportunity to think outside the box. You no longer have to contend with the shear physical size of a high performance ICE. An EV can be much more flexible with the placement of its heavy components. This is an opportunity to pursue aerodynamic and dynamic ideals and to produce a truly 21st century car that goes faster and drives better than any ICE car ever could and does it with less energy consumption than ever before. The inversely proportional relationship between performance and energy consumption can be broken (or at least made less so) with the right choice of battery chemistry. The best EV will be one designed as an EV from the ground up. Even the Tesla is a conversion of sorts. Take a Lotus Elise stretch it by a few inches fit the EV components clad it in some new carbon fibre panels and that’s the Tesla. Very slick but still a conversion and conversions contain compromises.


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## John (Sep 11, 2007)

The Lexus is so out there I think it might have some real world practical drawbacks. The A pillar is so large and far forward I think it would create a large blind spot right where you would want to see as you negotiated a turn. If you look at the pictures of the gas versions they might have an extra window above the front wheel to alleviate this issue. Aside from this it is very unique and would make a great project. I like the wasted teardrop shape at its core.


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## John (Sep 11, 2007)

Another design I think is noteworthy.















Kia sidewinder


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## ZeffriN (Jan 7, 2008)

omg Datto 240Z looks so tough, I'm in love... I wonder if I can get one here.

Otherwise 77 celica looked niced... I think the mustang while an awesome looking car might be too heavy.. they're 1.6 tonne or so aren't they.. I mean sure you can slap in a huge AC motor and it'll move ok, but it'll be pretty tragic compared to what people expect from a mustang....

Huge thread and I admit I didn't read it all, but this is awesome... if I had the resources to go through with it I'd love to do an EV from the ground up, purpose built will surely win the day.

If you don't mind the few extra coins AC motor and controller will cost, it's your best bet I think.. especially if you want regen. Siemans have a watercooled 94kw and suitable controller for around $4-5k USD for the package I believe, last time I looked it was $3k the motor and 1.5 for the controller I think... anywayyyy some motor like that is great because of course the water cooling extends service life, allows you to drive it harder for longer without the controller having to start rate limiting it and means you can use a standard heater  Although in your case, standard might not be much of a motivator...

I'd be interested to see AWD, but I wonder if it'd be possible to link 2 controllers together to drive 2 motors, perhaps less powerful... 50kW each, one for rear and one for front wheels to save the power lost to the drive shaft, and since removing the exhaust components gives you the space for such luxury... however once again I guess this consideration won't apply to you... I dont know much about wheel motors but theres something I don't like about it... having coils and magnets in the wheel where it can't protected from vibration or impact I dunno, I dont like it... but maybe I'm wrong...

Either way looking forward to seeing some designs when you get that far, I love a good project and a ground up build is huge!

PS Oh man that Datto 240Z is so sweet, if I can get those in Aus Im going to have to consider it


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## david85 (Nov 12, 2007)

*Just a quick correction here.*

When I listed the cars (toyo, dats, and ford), I was referring to the appearance, not really to use them as a conversion platform, although that is still possible (mustang conversions have been done before). Most cars from the 70s are going to be on the heavy side, simply because it was expected back then to use thicker steel.

As it turns out I was wrong about bodies being available for the mustang mack 1, instead its the fastback thats available. The repro is completely F/g and (with some elbow grease) can be made into a mono cock structure to be lighter than most any steel bodied donor. The weight savings will come from using light materials.

For the long term, the molds for the car will be made in house, and the car will take any shape I choose, thats why I wanted some feedback for apearence. At close to 3000 views and 10 pages, I think I got the word out. Thanks to everyone who weight in so far, and feel free to keep the conversation going. Time is tight right now, so i might not be able to post as much as I like, but I should have some updates fairly soon.

For motors, I pretty much sold on either a 3phAC drive, or a brushless DC motor. With 3ph AC being available without perminant magnets, not sure about brushless DC.


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## david85 (Nov 12, 2007)

Well, not too much new to report, but I did make an interesting find, another EV motor supplier, and I think they make wheel motors. I haven't tried contacting them, but the language of their website seems to be more open than most.

http://www.solomontechnologies.com/index.html

Cheers.


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## MitchJi (Dec 14, 2007)

david85 said:


> Batteries
> 
> Lithium Iron Phosphate seem to hold promise for safety, price, and cycle life, but can ThunderSky be trusted? If any of you have had used these batteries, please share your experience, because as it is right now, they seem to be the best bang for buck in terms of performance and cost.
> 
> ...


Hi,

Some serious reliability issues with ThunderSky have been reported on the EVDL.

Electrovaya are supposed to be (according to Bricklin who signed a JV with Electrovaya) about 14 lbs per kWh including the BMS on a 1.5kWh module (20 lbs for the module). 

He states they can produce them for less than $400 per kWh but they have yet to do that and they might not be available to individuals. If they are the prices would probably be higher.

The prices on the nannosafe batteries are extremely high. I forget the exact price but (35kWh) was well over $40k, I think something like $80k or $100k.

Mitch


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## david85 (Nov 12, 2007)

Yes, I also heard about electrovaya's contract with bricklin, after starting this thread.....

The only thing that impressed me about nanosafe's battery was the cycle life, energy density is not bad, but nothing to write home about either. Cost certainly has to come down though, the only reason they are scraping by right now is because the product is heavily subsidized.

I am also not sure about thundersky's batteries. I know early ones were unreliable, but are they still having problems? I wasn't able to find much info from recent conversions, possibly because no one wants to risk it. Did read one the odd case of a satisfied customer, but not much to draw a conclusion. Do you have any recent reports?

Thanks for posting.


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## MitchJi (Dec 14, 2007)

david85 said:


> I am also not sure about thundersky's batteries. I know early ones were unreliable, but are they still having problems? I wasn't able to find much info from recent conversions, possibly because no one wants to risk it. Did read one the odd case of a satisfied customer, but not much to draw a conclusion. Do you have any recent reports?


Hi,

Given that batteries are very expensive and problems could take years to develop before I purchase a large battery pack two criteria need to be met:
1. The batteries the company sells need to have a very good track record. A few good reports or a brief period with no complaints is not sufficient in my opinion to purchase an expensive battery pack.

2. I have to believe if there is a problem with quality the company will make it right. Thundersky has done nothing AFAIK to pass this test.

In other words, in my opinion, at this time Thundersky fails both tests.

Mitch


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## dataman19 (Oct 7, 2009)

david85,
Where are you at in your EV car project???...
I am doing the same and have come to the conclusion that operating an EV conversion shop will provide the background and funding to develop an EV Car/Truck Line.
..
My business model involves bulk purchasing to get wholesale (and the resultant retail) pricing down significantly. This will provide for a more economical conversion cost.
..
The experience with the many different customer cars and the conversion results will provide a wide range of performance data to make realistic decisions.
..
I also understand that the UAW and GM are receptive to accepting reasonable offers for their Saturn facility in Spring Hill, TN. Why Saturn? Why not?
..
Saturn is a stand alone facility. they make everything! They have the Plastics Presses to Die cast the entire body panels. Think about this.....
..
Die Cast Body panels are super light weight, they are strong, durable and nearly dentless. Smack one with a hammer and the hammer bounces back.
..
Saturn has its own testing facility and track. No explanation of benefits should be necessary.
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Saturn have their own production models that are ready for EV.
...
Saturn is a US car Maker that is dictated to be liquidated, Why, because Congress said so>>>>>
..
The Auto Maker bailout directs that the auto makers give away the market, close factories, close dealerships and put people out of work - as opposed to the wall street bailout that provided for multi-million dollar bonuses to the execs who caused the problem, or the Bank Bills that provided the financial incentive to foreclose on mortgages and put people out of their homes. But I digress...
...
Maybe we should all kick in about $1K and buy the Saturn plant. Then we could actually produce an electric EV and sell them.
..
Just food for thought
..
dataman19


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## david85 (Nov 12, 2007)

Didn't realize anyone was still reading this thread. You have to remember this is the second thread I ever started after signing up. I agree that detriot and most of the workers there are not helping us very much.

I also agree that starting with a conversion is a good beginning. I've learned a lot so far and would like to push it as far as I can. Range is still the thing that I haven't been able to prove. May not be able to make the range tests this year but my saturn conversion is moving under its own power now. Check the link in my signature for all the details.


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