# Long Range Conversion Wanted



## dtbaker (Jan 5, 2008)

ouch, 100 miles at highway speed REQUIRES probably a nice aero donor car, high quality controller, and 144v worth of 200sh LI battery pack.... which is gonna get expensive! Doable, but expensive.

You're looking at $11k just in batteries (48*200*1.1) plus a solid $9k in everything else...


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## madderscience (Jun 28, 2008)

A vehicle with the range you need is possible, but you will have to revise your budget expectations. 

In order to get real world day-in day-out 100 mile range, you must have a good sized lithium battery pack. Lithium is not cheap. 

If I were building a 100 mile commuter I would find an early (2000-2006) honda insight ideally, or some other very small aerodynamic 2 seater. It should be able to achieve around 200Wh/mile battery-to-wheels (or 5 miles per KwH) at around 55mph on level ground. then, you will need about 20KwH of usable battery pack capacity to do 100 miles. So, you are looking at something like a 156v, 200AH battery pack, or about 45 200A lithium cells. The best price I know of for lithium is $1.10/ah excluding shipping, tax, BMS, etc. so you are looking at around $10K just for the battery. Add another 6 to 8K for everything else.

If you were to use a truck, yes you can carry more weight but it will be considerably less efficient (300 to 400 wh/mile battery to wheels) and so you will need to scale up the battery pack size, motor and controller and everything else to compensate. Only do it if you NEED the extra cargo space.

Good Luck.


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## Woodsmith (Jun 5, 2008)

Hiya.

For my commute I am looking at 32 miles at 70mph with half a mile of 30mph at each end, each way and no recharge, for my conversion and I have gone with an MR2 as it is fairly small and slippery if I take the wing off the back and do some body mods. 

I am looking at using either 40 x 200ah LiFePO4 cells to just about get that range and speed. I have the space and can just about get 50 x 200ah if I find that the range is too short. That still works out in the £10k+ range for cost of batteries.


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## killerformula (Nov 23, 2009)

Thanks for the replies so far, I realize this sort of thing is probably pretty common knowledge around here so I appreciate the perspective.

I'm not absolutely sure I can count on a recharge at work, but if I could that would certainly help reduce my battery needs it sounds like. Of course, then if I get an agreement that I can charge at work and somebody makes a stink about it, I then loose the efficacy of a car I've spent thousands designing on the expectation that I can recharge my batteries remotely. It feels pretty risky.

The whole commute is not at 70 mph. THe entire length is about 45-50 of which about 8 are freeway. The rest is maybe 50 mph? I'm guessing that's not going to help me much...

K


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## m38mike (Dec 27, 2008)

killerformula,
Do you have the option of avoiding that 8 miles of interstate and keep your travel speeds at 50 or below? That will save significantly on the battery power you'll need to carry. Especially if you use a light truck. Power needed goes up exponentially as speed increases. 

Just my 2 cents.


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## Bowser330 (Jun 15, 2008)

m38mike said:


> killerformula,
> Do you have the option of avoiding that 8 miles of interstate and keep your travel speeds at 50 or below? That will save significantly on the battery power you'll need to carry. Especially if you use a light truck. Power needed goes up exponentially as speed increases.
> 
> Just my 2 cents.


I concur with m38mike, high speed DIY EV driving can drain your AHs, driving at 50 the whole way would increase...

Another way to see it is that if it takes your truck/car 10kw (15hp) to maintain a speed of 50mph, then a battery pack that is 10kwh (kilowatt-hours) could power you 50 miles for one hour, so a 15kwh pack would be needed to get approx. 75 miles....


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## m38mike (Dec 27, 2008)

killer,
on getting a charge at work, I'm in the same situation you are. I can't charge at work because it's a federal office. But I approached the private business next door about buying electricity from them each day I drive my EV in. They actually got excited about the idea. I figured that I will draw about $0.75 worth of juice in a work-day charge. So we agreed that I would pay them $1 for each day I plugged in. They were very happy to support an EV that way. So I bring a 100 foot extension cord with me to plug in when I drive to work.

Talk with other businesses within walking distance of your work. I'll bet you can find one that would be happy to support your EV.


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## gary k (Aug 19, 2008)

Push the recharging at work - it'll bring your cost within budget and help promote EV's. There is so much momentum for this right now that any place should provide EV charging, including a Federal building (especially federal). If you get a "no", keep pushing it up until it gets to somebody that has a clue as to what we are trying to do on the planet Earth - energy independence and sustainability. Get your local EAA chapter involved with the city or whatever else it takes to keep pushing it - it's very important. We need to get charging stations everywhere just to increase awareness and let people know that charging is here and EV's are coming. Get someone else at work interested in EV's so you have more people asking. It is so simple to put a 120 GFI outlet to help our country and reduce pollution that there is no excuse. Don't make me come down there and talk to them ;<}

Good luck with the EV build - go for it! You'll be able to upgrade to lithium or better down the road and your vehicle will get better with age.


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## Bowser330 (Jun 15, 2008)

m38mike said:


> killer,
> on getting a charge at work, I'm in the same situation you are. I can't charge at work because it's a federal office. But I approached the private business next door about buying electricity from them each day I drive my EV in. They actually got excited about the idea. I figured that I will draw about $0.75 worth of juice in a work-day charge. So we agreed that I would pay them $1 for each day I plugged in. They were very happy to support an EV that way. So I bring a 100 foot extension cord with me to plug in when I drive to work.
> 
> Talk with other businesses within walking distance of your work. I'll bet you can find one that would be happy to support your EV.


Be careful about putting your extension cord on public property. You don't want anyone to sue you because they tripped on your cord.


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## Voltswagen (Nov 13, 2008)

m38mike

A 100 ft extension cord has a significant drop in voltage.
I used a 14 gauge one at a car show for my 10 amp 120v Quick Charger. It took nearly twice as long to put 20% into my pack compared to charging in my garage with a 10 gauge 8 foot cord.

Here is a little article on extension cords and voltage drop.
As you will see....as the amps go up.....the drop increases.
At 10 amps on a 100ft 14 gauge the drop is 6.1v only 5% right?
But as some EE could perhaps explain it better than I....the effect on the charger is magnified. And colder weather increases the drop.
http://home.mchsi.com/~gweidner/extension-cords.pdf


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## david85 (Nov 12, 2007)

My car *MIGHT* be able to meet those requirements when its done, but I can'd say until I roll that trip odometer over 160 kilometers for real.

My cost is over $20000USD before misc parts and shipping, so I'm sorry to say its not going to happen on a $6000 budget. If you can recharge at work it would help, but even then, thats not going to be easy on $6k and still have something that is highway capable.


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