Packed Up: A123’s battery cells (above) have been integrated into a T-shaped pack engineered by the German firm Continental.
In all lithium-ion batteries, electricity is generated when lithium ions shuttle between two electrodes while electrons travel through an external circuit. In Chiang’s early experiments with lithium iron phosphate, the parts of the material that contained lithium would separate from those that didn’t as the lithium ions moved in and out of an electrode. That changed the crystalline structure of the material, and its performance deteriorated. But, Chiang discovered, when the particles of lithium iron phosphate are small enough–and the electrode has been modified, or “doped,” through the addition of other metals–the material’s crystalline structure changes far less. As a result, the lithium ions can move in and out faster, without degrading the material. Altogether, Chiang found that the modified material charged and discharged faster than ordinary lithium iron phosphate, and it lasted longer, too.
Extraordinary though the new battery material seemed to be, Chiang realized immediately that it wasn’t ideal for portable electronics. There didn’t seem to be a ready market for light, compact batteries that delivered large bursts of power. Hybrid vehicles, a natural fit, were only beginning to appear on the market. What Chiang didn’t know was that a major power-tool company was working quietly on a new generation of cordless tools, and it was having trouble finding a battery that would meet its needs.
In 2003, representatives of Black and Decker met with Fulop and A123’s CEO, Dave Vieau, and told them that they wanted to make cordless power tools that would perform better than tools plugged in to the wall. A123’s material seemed like a perfect fit. In short bursts, it can deliver more power than a household circuit. And it had other features that would be attractive on a construction site. It could be recharged quickly (to 80 percent of capacity in 12 minutes or less), and unlike batteries made with lithium cobalt oxide, it could survive harsh treatment without catching fire.
That, at least, was the theory. When Fulop and Vieau first met with Black and Decker, they had only a model of a battery cell, half a gram of material, and a PowerPoint presentation. What Black and Decker needed was a company that could produce millions of batteries. “There was a lot of emphasis on the material, but what we had to learn how to do is to engineer the complete cell,” Chiang says.
Within a year of signing its initial agreement with Black and Decker, however, A123 had produced a commercially feasible battery. By November 2005, its first products were coming off assembly lines in Asia. In less than three years, the company went from building a demonstration battery the size of a coin to building 50-meter-long coating machines and 28,000-square-meter factories run by hundreds of employees. By 2006, customers were buying its batteries in a new line of professional tools sold by Black and Decker. In short order, A123 was manufacturing batteries at the rate of millions a year.