Hello Folks,
I look forward to communicating with you all.
For a very very long time I have thought about building an electric car. I’ve been recently digging through a couple web sites (White Zombie, Beepscom.com, e-volks, etc…) and I’m starting to get an idea of what I might need. I’ve thought about opening up an electric hot rod shop and begin by building a 27T electric roadster. The roadster could be built as a lakester to save cost and be very aero dynamic, I love lakesters since I’m such a big Bonneville Salt Flat Junkie. The great thing about a roadster is that you don’t need A/C or heat or just about anything else. Rather then buying a motorcycle to save gas it would be much safer and much more interesting to build an electric roadster.
I would be hoping for a 50 mile range at freeway speeds (70 MPH). A car is not a car unless it can drive on the freeway and be used as a commuter. I’m considering 12 Optima Yellow Tops for 144 volts with an additional mini optima for signal/headlights lights. I was looking at the Warp 9 motor rated for up to 196 Volts. The tranny would be a VW transaxle to help simplify installation and drive train. Which controllers should I consider? A track T body/frame with axles wheels is about 800 pounds; add batteries, controller, motor and she should weigh in at around 1800pounds.
Am I heading in the right direction? Is an automotive battery going to survive being charged and drained daily for 3-4 years, or should I look at 6V golf cart batteries that are designed to be drained/recharged?
I think you’re going in the right direction. It may be quite optimistic to achieve 50 miles with yellow tops. I have seen many designs online that get around 10-20 miles per charge out of them and driving at a max of around 60 mph. You’re probably going to have to look into other types of batteries (NiMh, Lithium Ion). They’re more expensive, but it more efficient to buy higher density batteries than to add more lower density batteries due to the weight.
The Warp 9 motor is a pretty good choice. You’ll get some punch out of it and it is quite practical.
I’m not too sure about the controller. There are a few of them out there…but I haven’t gotten around to looking at those yet.
LiPoly is probably too expensive but NiMh might be okay. Are there any reasonably-priced controllers that also have battery management options to keep each cell balanced and cycled? I have an electrical engineer friend who is very good with Linux, I wonder if we could integrate some type of computer to manage both a controller and charger. I little palm that can be unplugged from the car and then reprogramed via PC sure would be cool.
What NiMh are folks using? I need stuff I can buy off the shelf.
I come from the R/C flight, I wonder how cheap I could get the 3.4v 2500m/amp 20C cells for? Imagine 42 ounces/2.6 pounds for 144 volts! How many millamps does something like a yellow top have?
My car is the same weight and has the same componants which you speek of. A Warp9 DC motor, A 156V, 1000A (speed controller), A VW 5 speed tranny. I would look at getting a pack with at least 50-60ah of total capapcity (8KWH). If you have 1800 lbs of total weight, this should be good for 50 miles of normal driving. I have 100AH cells (x50), with the same motor and can stretch it well over 100 miles per charge (if I drive mellow). If I turn it up (amperage), more power is available yet range is reduced. The Warp9 is actually used in many cars which are over 3000lbs. Why push your motor that hard? You are on the right track. I know this from experience.
-Nikolai Sprinkling
