First, I'd like to thank Thingtodo for the excellent description of how to properly connect wires in high-power applications. I'm just not sure of where to get a hydraulic crimper and what the taping procedure is about.
I'm a bit more familiar with some of the EV parameters; I've made a silly detailed spreadsheet of the E*clipse, including aerodynamic stuff, weight removed and where it was, added weight and where it will go, tire diameter, gearing, different motor options, battery pack options, etc etc.
Throwing a couple of numbers into that spreadsheet -
We'll use the 6.86:1 ratio of the MGR, and consider no weight or aerodynamic issues.
26" tires will allow a top speed of 115 mph, based only on the motor rpm limitation. However, reality is aerodynamic drag, friction, etc are working against hp that decreases from mid rpm > max rpm.
The car will be power limited long before 115mph.
Personally, I don't see any use for increasing the tire diameter unless you find a way to dramatically reduce the aerodynamic drag or dramatically increase the power from the motor.
The speed freak in me is the one advocating multiple motors for my project.
Regarding battery weight, and here's a place I've spent ridiculous time searcing for some sort of "optimum"... The lbs/kwh number will directly relate to decisions here.
Consider lithium cells rated at high discharge values. The motorcycle racers and a few top-end electric racecar builders understand this. There are a lot of different pack options because each of the cell listed below have different voltage specs.
Here are some possibilities:
Enerdel 15Ah pouch cells rated at 15C discharge.
NEB 20Ah hybrid super-capacitor rated at 25C discharge
CALB 40Ah cells rated at 12C (torture tested on EV TV)
A123 20Ah pouch cells rated at 30C discharge
Nissan Leaf 23Ah (I think) cells rated at 8C discharge (This is cell, not module data)
If anyone has any more options, I'd love to hear about them.
- E*clipse
Many of the cells listed above are pretty much unobtanium.
Either the cost is ridiculous, or the only way to get them is sponsorship or taking your chances dealing with China. I've decided to go with the Leaf cells because I've found a reasonable source for them and they're pretty close to my performance requirements.
Quote:
Originally Posted by freebeard
You do better at descriptions, and you're starting to see the beauty of the whole thing. The VW transaxle doesn't weigh much more than 100lb. So I have the weight of the motor, a full tank of gas and the shift rod/lever to play with. For planning—how many pounds per kilowatt-hour?
Peak power's in the middle of the rpm band. The Lexus/Highlander probably has 28" tires. So maybe I can build an undervolted (288v) version with 26" tires as proof of concept; and then double the battery pack and go to 30" tires to put it out on The Salt.
Edit: I'm going to hold off on that pre-build thread, since the drivetrain should be available tomorrow. I should decide whether to go with the original thread in Aerodynamics, or start a new one here or in Ecomodder Central. |