E-meter, We Love to Hate it! [RE-wrenches]

[R. Sparks Scott]

	I may be answering my own question here, someone tell me if I'm right:

	Overall battery efficiency must take into account not only Ah of
consumption, but terminal voltage during charge/discharge to provide Kwh
readings which can be compared.
	Example:

	In my EV, (using greatly rounded-off values), 45 Ah of consumption at a
terminal voltage of 100 VDC = 4.5 Kwh. Recharging the batteries puts back
approx 46 Ah at ***125 VDC*** = 5.75 Kwh. 4.5 / 5.75 = .78 or 78%
efficiency. This is a lot closer to the 80% figure that I have always
understood was correct for L/A batteries.

	Obviously, to get an accurate calculation, one would have to log the
actual terminal voltage over the entire charge/discharge period, no easy
task, especially in an EV, where the terminal voltage ranges from 90 - 130
volts over that period. Sounds like a job for a micro-controller and analog
input device.
	Too high tech for me, I gotta go rake leaves....

	-S

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