Killacycle - electric drag racing motorcycle and world record holder
Scotty Pollacheck astride the world's quickest electric motorcycle powered by $12,000 of A123 Systems M1 lithium-ion batteries. Despite pushing the batteries to the boiling point of water and sucking 4000 watts/kg of power from the pack, the team has yet to replace a single cell, proof these batteries are different in a big way.

The Secret of the Killacycle's Success

Killacycle owner and team manager Bill Dube shares the secrets of the world's quickest electric motorcycle.

By Bill Moore

What's it like to go from zero-to-sixty in 1.4 seconds?

Fifty-four year-old Bill Dube doesn't know. He turned over that job to young Scotty Pollacheck, who is half his age and has ice water in his veins.

Instead, he gets his thrills these days dreaming up ways how to make his record-holding Killacycle a bit quicker, endlessly tweaking, continually experimenting with a motorcycle that started life as a highly-modified Kawasaki but long ago left its Japanese origins far behind. According to the effervescent Coloradan, who has been building electric cars for decades, Killacycle is never the same machine from one race season to the next, and often between races.

But as excited as he is talking about the Killacycle, he simply can't contain his enthusiasm for the secret ingredient that makes 150+ mph quarter mile speeds possible: $12,000 worth of A123 Systems M1 lithium ion batteries.

"These are the batteries," he says emphatically.

He should know, he's destroyed more than his share of more conventional batteries over the years, pushing them to their limits and then some, leaving them smoking hulks at times.

Bill began my education into battery technology by first explaining the "positives" of A123's 26650 cells. They are:

  • Specific power -- He claims the bike is pulling an unbelievable 4000 watts/kg! At the end of a quarter-mile run, the custom-built battery pack consisting of 880 cells is the temperature of boiling water, 100 C/212 F.

    "Everything works better when hot, " he teases. Before a run, the team warms the battery up to 75 C. Pollacheck, who weighs wet somewhere around 125 pounds (56 kg) also spins the 10 inch-wide rear tire until it smokes, making it super sticky for added traction.

  • Safety -- In his view, A123's iron phosphate-based lithium ion chemistry is the safest he's ever worked with. He asserts you can drive a nail through the cell and it will leak a small amount of organic solvent. Other, higher specific energy lithium ion batteries will burst in to flames, he told EV World.

    "Drop a wrench on it, and nothing happens."

  • Cycle life -- Given the abuse Killacycle heaps on the A123 cells, you'd expect that the company, which supplies the cells to Dube's team for promotional purposes, would have to ship them a constant stream of replacements. They don't. In the 18-months that Killacycle has been using A123 cells under the most extreme conditions imaginable, Dube had yet to replace a single cell.

    Dube's single negative is that he wishes the batteries had more specific power compared to other off-the-shelf, laptop-type batteries. Still, he's satisfied, telling me in a follow-up email that they are a "bottomless pit of energy". And the Killacycle is surprisingly efficient, consuming a mere 80 watts per mile in ordinary driving; a number that jumps to 300 watts at 150 mph.

    He told EV World that he has discovered over the months that the actual performance of the cells exceeds the value of the company's spec sheets. He pointed out that A123 claims the cells have a cycle life of 1000 discharge/recharge cycles at a C10 rate (complete discharge in 6 minutes time). In the fine print, the 1000 cycles is determined at the point when the batteries have lost 5 percent of their storage capacity. Dube pointed out that the typical battery specification sheet uses a 50% loss of capacity as the demarcation point. Extrapolating that to A123, he believes their cells are good for 10,000 cycles. He has found A123 very conservative in their specifications numbers.

    "This battery is bullet-proof. It's Mr. Fusion," he said referring to the power source of the fictional Delorian time machine in the Back to the Future film triology.

    Dube explained that A123 chose his team to support with batteries because he and his team mates had demonstrated they knew how to "care and feed" for the batteries by developing their own battery management system or BMS. He estimates that including the BMS system, the battery pack would cost in the neighborhood of $40,000 to have someone else assemble.

    In addition, the Killacycle team would not only give the company the kind of exposure it wanted to demonstrate its battery's capabilities, but also provide it with detailed performance data.

    The combination of 'Zilla controller, Advanced DC motor, and 880 A123 cells, resulted last year in a 8.76 quarter mile and an unofficial 152.7 mph. The closest other electric cycle's best performance is 12 seconds for the quarter mile. In fact, Dube contents that Killacycle is quicker than two-thirds of the rest of the field, including the gasoline-powered bikes.

    The team is preparing for its assault on the official electric motorcycle speed record in Phoenix, Arizona, which it missed last season when it blew its motor on its fastest run and couldn't repeat the necessary second run within the specified time limit. And that run was only one of many it had made that day, vividly demonstrating the resilience of the batteries, if not the motor.

    While Dube plans to continues pursuing more electric motorcycle speed records, he's also thought about taking on the Pikes Peak hill climb, a grueling, twisting race up mainly gravel roads. That will likely take a different kind of bike, probably one with all wheel electric drive so he can take better advantage of regenerative braking to recapture the bike's energy.

    For Dube, who drives his converted, NiCad-powered VV rabbit 28 miles to work every day, it's definitely the hare who wins this race.

    Team left to right: Derek Barger - Fabrication, Steve Cicioro - BMS and electronics design, Scotty Pollacheck - Driver, Bill Dube' - Owner, Crew chief

    Times Article Viewed: 31254
    Published: 23-Mar-2007


    blog comments powered by Disqus