A couple of weeks after my ill-fated attempt to test-drive the
plug-in car in Washington, I’m outside the headquarters of
battery maker A123 Systems in Watertown, MA. Out front is the
shiny, aggressively styled GM Volt. The car is there because GM
has selected A123 as one of two companies that could end up
providing the battery technology for the Volt. A123 makes a new
type of lithium-ion battery. Lithium-ion batteries, which are
now used widely in laptops and cell phones, pack a lot of energy
into a small space. They take up just one-sixth the space of the
lead-acid batteries used in previous types of electric vehicles,
and they weigh one-sixth as much. They also take up less than
half the space of nickel-metal hydride batteries, the kind used
in today’s conventional hybrids, while weighing just a third as
much. But the type of lithium-ion battery that’s used in laptops
and cell phones has problems, including the occasional tendency
to overheat and, in rare cases, burst into flame. Troubling as
this instabil