From: lektwik via EV <email@example.com>
>96V = Slug
Not necessarily; but in this case, probably correct.
Here's my guess: A 6v golf cart battery has an internal resistance of about 5
milliohms (0.005 ohms). A 96v pack has 16 of them; so the resistance is 0.005 x
16 = 0.08 ohms. Let's say the Zilla limits voltage to 72v (i.e. it won't pull
the pack below 72v). Then the most current you can get is I = V/R = (96v-72v) /
0.08 ohms) = 300 amps.
In practice, the resistance of the pack is a bit higher due to the wire and
connectors. So a 200a max current is probably the most you can draw from the
golf cart batteries before their voltage under load falls to 72v.
Now, if you had a different kind of batteries with less internal resistance, or
a controller that would cheerfully pull the battery voltage even lower, you'd
have a lot more current, and peppier performance.
For example, my old ComutaVan had a 72v pack of golf cart batteries, and a
contactor controller. It would cheerfully pull 1000a from the batteries, and
spin the tires if you "floored it" from a dead stop. I tried a Curtis 1221 400a
controller; and it was *worse* than the contactor controller for accelleration,
because it never came anywhere near 400a due to voltage sag.
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