Well, I said I was going to do it and we finally got the prototype built.

We just built a 600 cranking amp, 11.5 A-hr, battery that weighs just 3.7 pounds. I've been testing it in my GMC van for the past week here in the Denver Winter. It snaps the van right over every morning without a problem. The van cranks faster than it did with the standard lead-acid battery.

It is smaller than the Odyssey 680 so it fit in the same battery box with a couple of foam blocks for spacers.
The battery has four status LEDs that tell you the cell balancing electronics are working OK. We are using A123 Systems M1 cells with our own custom battery management electronics. The A123 Systems cells are proven to be the safest Li-Ion cells on the market. No problems with fires (like laptop cells) because the chemistry they use is completely different.

The battery can be damaged by running it completely flat (like leaving the master on) and holding the battery below 8 volts for a long time. It can also be damaged by charging it over 15.0 volts. It will likely still function after such abuse, but it won't be nearly as good as it was originally. If you don't abuse it, it should last you for many years.

I think we will be in production in about a month, maybe two.

Specs:

3.7 lbs
600 cranking amps
11.5 amp-hr
Approximate maximum dimensions: 3" wide, 5" long, 7" tall (including terminals)
Charging voltage = 13.8 to 15.0 volts (anywhere in this range is OK)
Nominal voltage = 13.2 volts (Just a touch higher than your typical lead-acid, so it spins the starter a touch faster.)
Cell cycle life rated at 2000 cycles (80% DOD, 90% capacity remaining) 10,000 cycles (80% DOD with 50% capacity remaining) @25 C
Cell specs: <http://www.a123systems.com/html/products/ANR26650M1specs.pdf>http://www.a123systems.com/html/products/ANR26650M1specs.pdf
Maintenance free
No heavy metals (iron-phosphate type cells)

At this time, we estimate the retail price will be $595. (Yeah, I know this is not cheap, but this is the state-of-the-art battery technology so the parts to make it are not cheap.)

Here is a picture of the prototype. We have it in a clear Lexan case so we can keep an eye on it. The production battery will have a smaller opaque case with a clear top lid (terminal end.)
http://www.killacycle.com/photos/aircraft-battery/Prototype1InVan.JPG


We have been racing these cells in the KillaCycle for about a year, so we know _all_ about them.
<http://www.KillaCycle.com>http://www.KillaCycle.com (Be sure to watch the movie clip.)


Bill Dube'
<mailto:bike@KillaCycle.com>bike@KillaCycle.com



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