Quicksilver

n 1974 Mike Corbin set the Electric Motorcycle Land Speed Record at Bonneville with “Quicksilver”- a bike that, in 1972 set the previous Land Speed Record running lead/acid batteries.  The 1974 record of 165.397MPH  stood for over 30 years. 

The bike was running silver-zinc batteries (thus the name).  Now, you may have never heard of silver-zinc chemistry, or you may think it’s a long-lost ancestor of the current lithium battery we all run today.  Well, you’d be wrong.  Silver-zinc is a well known chemistry, it’s still in use, and to find the poster child for sliver-zinc chemistry you’d have to go to outer space.  Mars, to be precise.  Yeah, we’re talking the batteries in the Mars “Curiosity” Rover, and yes, Yardney is still around.

Take a look at their website, here.  Yardney is into lithium chemistry too, but look at these numbers for silver-zinc, here, on their datasheet.  Here’s what jumps out:  Wh/lb ratings of anywhere from 43 to 69.  For reference, an average LiFePO4 prismatic cell is around 30-35 Wh/lb.  Back in ’74, they represented a 8x “more available power” advantage over lead.

Here are the specs I could get:

• Silver Zinc Batts by Yardney
• System Voltage: 120 v , 1200 amps
• Charged with industrial off board charger
• Motors, starter motors from A-4 fighter plane, bought military surplus.  Intermittent duty, Series wound DC , silver conductors
• LOA: 9’6″
• Weight: 772lbs (935 lbs with rider)

Oh, the controller?  How about this:

• Three stage magnetic contractors , with a spring loaded giant knife switch for shut off.   A 250A fuse in parallel bought time for knife to clear without arc.  The magnetics could not survive the opening arc.

To which I responded, “holy shit”.  To which Mike responded, “That’s what I said…”

The bike was the first electric vehicle raced with battery technology beyond simple lead/acid.

Source: The Electric Garage: The Corbin Quicksilver