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Old 12-24-2008, 08:25 AM   #3 (permalink)
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I ran over the calculations a while back when I picked up a Paseo (fairly similar car) with a siezed engine. Here is what you need to look at.

It will take roughly 450 Wh to keep you going 60 mph. I know its not 55, these were my numbers. This is also a bit conservative of a number.

450 Wh * 45 mile range till batteries are totally dead = 20250 Wh battery pack capacity

20250 Wh * 2 = 40500 Wh pack so you don't go below 50% pack charge to retain good battery life

140 Ah * 12V deep cycle battery = 1680 Wh per battery This is a bit optimistic of a number. I've been told you won't get that much Ah out of a battery when discharging it as fast as you do in an EV.

40500 Wh desired pack capacity / 1680 Wh per battery = 24 batteries

These batteries weigh roughly 78 lbs a piece, so you're looking at adding 1872 lbs in batteries to the vehicle.

Now, you still have to find a 96V or better controller which is gonna cost you a fair amount (anything abouve 72V seems to go up fast). You also need a way to charge those 24 batteries.

Kinda sucks to run the numbers. I know I didn't like it, but thats what it is. I wish I had a job closer to home. I'd do it in a heartbeat.
Current project: A better alternator delete
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