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Discussion Starter #1 (Edited)
I am trying to build an EV.

I want a top speed around 150 - 175mph
I am going to construct most of the car from Carbon Fiber
I want the car to plug into a regular U.S. 110v socket
I would like to use Li ion batteries.
I also want a range of 200-250 miles
i would also like to implement Regenerative Braking

I have the carbon fiber under control but everything else i would like some of your help figuring out.:confused::confused:

Thank You,
Jeff H.
 

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Hi Jeff,

That sounds like a fun (expensive!) project.

Achieving speeds like that is not impossible in an EV, BUT... your vehicle will need to be very light (sounds like it will be), very aerodynamic, have very low rolling resistance, and you'll need very high voltage to achieve that sort of performance.

Having said all that, the amount of lithium batteries needed to propel the vehicle to a 200-ish mile range at typical freeway speeds will probably last just long enough to accelerate to 175 mph before needing to be recharged.

The faster you go, the more energy you pull from the pack. For example, if you drive 40 mph and want to go 80 mph, the air resistance on the vehicle will quadruple even though the speed only doubled. To go the next step from 80 mph to 160 mph, it will quadruple again. As such, each time there is a doubling of speed, there is a 4x increase required to reach and sustain that speed. This is why a Bugatti Veyron requires a 1001 horsepower engine, otherwise it would never reach its top speed of about 256 mph. It will likely consume 4x the fuel to go 256 mph than 128 mph.

Your goals are not impossible, are not cheap, and sound like a heck of a lot of fun. Please let me test drive it when it's built. :) I love fast cars.


Edit - one last thing I forgot to mention. Today's cars using lead acid batteries take as much as 10-12 hours to charge from a 110v socket, depending on depth of discharge and overall capacity. Those same cars typically do less than 40 miles range when they require that long to charge. If your car can do 200 miles per charge, then a standard 15a 110v socket may require 50 to 60 hours to recharge from "empty".

The more volts and amps you can feed the charger, the faster you can 'fill up.';)
 

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That project is possible if you cut back the top speed and range dramatically. Build it for a top speed of around 75mph and you might find that the range will be around 100 miles or more.
 

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Discussion Starter #4 (Edited)
With the top speed mabye only like 20-35 miles at tops speed, how would i recharge it faster. after i make the first one i would like to sell these so, i liked the socket because everyone has them but if it would take 50-60 hours lol, how would i recharge in 3-5 hours?

What kinda of electronics would i need to control this monster, all i know is i like fast italian style sports cars an they have to be light as shit so, every thing else is greek to me.

Thanks for your help and your patients

Kitty i know it can be done, im trying to model my cars profomance around the Tesla, but i want it to be competitive too.
 

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I already answered the question about how to charge faster. :)

The more volts and amps your circuit can sustain the faster you can pump energy back into the batteries - at least to the point of sanity for your battery type.

In the US, everyone has at least single phase 220v feeding their homes. Stuff like your clothes dryer, oven/range, water heater, etc run at these voltages typically. Most houses are fed with about 100a or more at 220v, so it would be no issue really to charge at 220v 30a if your charger and batteries supported that. That would "fill-er-up" about 4x as fast, give or take, again depending on if your batteries can take that fast of a charge.

It may be possible to make a car do 170 mph for 20 miles, but that would be a LOT of battery weight (even with dense LiFePO4 batts), and to get the type of acceleration one would expect with a vehicle that can do that, you're going to need batteries that can discharge fast enough to supply that much power.

Most EV conversions, and even those that are built from the ground up have horsepower ratings of less than 200 HP peak with less than 50 HP continuous. Neither of those figures will get you to 170 mph, even likely with a very slippery aerodynamic design with low weight. Take for example the Ferrari Enzo- since you brought up italian supercars and carbon fiber :) It produces 651 HP peak, and weighs under 2800 lbs.

LiFePO4 batts are lightweight, but I wouldn't be surprised if you needed 2000 lbs of them to accelerate to 170+ mph with any italian supercar-like swiftness and stay there for 20-25 miles. And 2000 lbs of LiFePO4 batteries will set you back the cost of an italian supercar. ;)
 

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Discussion Starter #6
What if i went down to like 125-140.

I dont want to duplicate the tesla but i would like to resemble its power and efficiency, and perhaps only going about 15-25 miles at top, but i would want it to be able to withstand 60-70 for a bit.

Could the Li batteries with stand that 4x faster chargining? No chance you know the cost or where to find the cost of li batteries?

i would like 275-300 peak hp, but i dont care as long as it hits my speed fast, like 3-5 sec, less than 5 is way beter though.

What kinda of electronics would i need to control this monster?

any ideas where i could purchase a motor, or any thing else i may need?
 

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Discussion Starter #8
Jafo, thank you for that web site.

The motor im thinking of useing is that AC 150 on the web site Jafo gave me, how ever i have no idea what half the things this thing does, do.

OPERATING PERFORMANCE
Voltage 336 - 360 V nominal, 240 V min, 450 V max
Current 580 A max (drive), -200 A max (regeneration)
Torque 220 Nm, 0-5,000 rpm (drive), 85 ft-lb max (regeneration)
Power 150 kW max 7,000-8,000 rpm, 50 kW continuous
Efficiency (shaft power out / electrical power in)
91% peak ( 50 kW, 9,000 rpm)
86% road load (8 kW, 8,500 rpm)
>93% recharge (240V line, 10 kW)
------------------------------------------------------------------

Motor
  • Four-pole induction, high frequency design with inverter-controlled magnetic flux.
  • Dimensions*: 12" dia x 15" long (305 mm dia x 381 mm long)
  • Total weight: 110 lb, 50 kg (incl cooilng blower)
  • Maximum rpm: 12,000
  • Insulation: Class H, double-insulated
  • Cooling: Forced-air with variable speed pwm control
  • Sensors: Winding temp, tachometer
the whole thing is at http://www.acpropulsion.com/technology/gen2.htm

wish i knew more about EVs lol
 

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I think you'll need to go AC to accomplish what you want. Take a look at the AC article in the Wiki. It's a work in progress, but it will give you an idea of what few options are out there.

One of the motors on the Wiki is an AC Propulsion unit. That's the company that built the drive system for the Tesla. They're probably the best around. Perhaps the motor that was suggested above will do what you want it to and a lower price though. I seem to recall that Ac Propulsion wanted 20,000K for their system and that they do not sell to hobbyists.

As for the batteries, I would recommend Elite Power Solutions - because they're in my home town and I want to help them out :) They supply LiFePO4 batteries specifically for EVs. They also supply a custom battery management system (BMS) and charger to suit your specific needs. The BMS actually includes a touch screen LCD. How cool is that?!

You'll want to go with a pretty high voltage battery pack (or pack for short). The system that I'm planning will use a 648V pack. That sounds high, but that's 460V RMS which is a very common voltage for a 3-phase industrial AC induction motor.
 

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Discussion Starter #12 (Edited)
wow thanks, i had you till you hit that last paragraph lol.
i dont want to be a hobbyiest, i would like to make this and have it be the flag ship for JHaak motors.
Edit: would this work for my battery needs or would i need 2? or perhaps the 160-80 wich only seems to me to be 2 times as expensive and 2 times as big...
http://elitepowersolutions.com/products/product_info.php?cPath=1_17&products_id=41

Edit 2: the motor you linked is the one that i linked XD

Edit 3 lol: I really wanted an LCD screen, i wanted mine to show bat lvl volts and what not.
also i want to make the instrament panel a tv type thing with computer gauges, how ever i want it to move and be in front of me before i go making it look pretty

edit 4: http://elitepowersolutions.com/products/product_info.php?cPath=16&products_id=43 on there does that mean that i get 160ah for 288, for some reason i find this hard to belive...
 

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As for the batteries, I would recommend Elite Power Solutions - because they're in my home town and I want to help them out :) They supply LiFePO4 batteries specifically for EVs. They also supply a custom battery management system (BMS) and charger to suit your specific needs. The BMS actually includes a touch screen LCD. How cool is that?!
You need to find out if they'll give you a discount for referrals! Or maybe a couple bucks per post where you sneak in their company name. ;)
 

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Discussion Starter #14 (Edited)
im deciding to go in a diffrent direction,

I want a top speed around 65-70
I am going to construct most of the car from steel and aluminum with probably fiberglass body
I will use Li ion batteries from this link
http://elitepowersolutions.com/products/product_info.php?cPath=1_17&products_id=39
Good links for some motors would be good
I also want a range of 200miles
I would also like to implement Regenerative Braking
anyone know a good way to raise capitol? unfourtunatly my blood isnt quite as rich as id like it lmao.
i want it to look sporty and worth the money lol.
I also dont want to use more than 200wh/m

think if i played my card this could sell for 50-55k? looking to spend about 35k.
 
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