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Old 08-01-2017, 10:11 PM   #5 (permalink)
Ecky
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ND Miata - '15 Mazda MX-5 Special Package
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Electric motors are a dime a dozen. More of an issue is the battery and controllers.

This is a pretty cheap lithium cell:

https://www.ev-power.eu/LiFePO4-smal...u-case-CE.html

To get 144v, you'd need 45 of them in series, which comes out to about $1100. A controller might cost you nearly that much too, though I admittedly don't know much about that market. You'd be able to get 20 amps of assist for 1 hour taking the battery from full to flat, which you probably shouldn't do if you want it to last. That's approximately 3.5HP of power, after losses. 45 in series could support about 35HP of assist for 10 seconds, or ~10HP continuously, which would last about 15 minutes if you're leaving 10% capacity at either end. If you wanted 30HP continuous, you're looking at around $3000 in batteries, minimum, or you risk damaging the batteries from the current draw.

I could guess at how much power your truck needs to move along the highway - probably about 40-45HP, give or take. If you're getting 16mpg and added 3.5HP of continuous assist, it would bring you up to about 17.5mpg, assuming no gains in efficiency from things like staying in 4 cylinder mode longer.

By comparison, my car gets about 90mpg at 60mph. Adding 3.5HP of continuous assist might bring it from 90 up to maybe 130-145mpg. The absolute amount of fuel saved would be the same for both of us though.

Last edited by Ecky; 08-02-2017 at 06:45 AM..
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