THE DRY ROOM AT SOLID POWER’S
Louisville, Colorado, facility is abrasively
bright, and yet the low, encompass-
ing hum of the fans and chillers is oddly
soothing. It’s here in the humidity- and
contaminant-free production area where
Solid Power produced their first full-size
solid-state lithium-metal battery cells.
The cells, a shining silver contrast to their
surroundings, were a moonshot.
The technology, in theory, sounded too
good to be true: a 10x jump in power (or
10x drop in size) from traditional lithium-
ion cells. Solid Power was aiming for more
modest gains in its first prototypes, but
could still see an 80 percent improvement
in the near future.
Then on August 7, 2021, three engi-
neers donned protective Ty vek “bunny
suits,” entered the dry room, and drew
voltage from the largest protot y pe lithium-
metal battery to date.
Josh Buettner-Garrett, Solid Power’s
chief technolog y officer, monitored from
his office. He felt confident, but a little
apprehensive: “We knew we could make
something that looked like a batter y cell,
but there was still a chance we’d have
a brick.”THE LITHIUM-ION battery that Solid Power
hopes to make obsolete is already a mod-
ern marvel that earned its key researchers
a Nobel Prize. And the preceding lithium-
iodine cells of the 1970s lasted years
longer than existing alkaline-based AA,A A A, or D batteries, thanks to the material’s
unmatched energy density. They were, for
example, an immediate boon for pacemaker
patients, who could now rely on a battery for
10 years instead of t wo. But lithium’s greatest
impact on batteries came with the recharge-
able lithium-ion batteries in the 1990s for
portable electronics and electric cars.
Lithium has been the focus of battery
research for decades because it’s an excel-
lent conductor. Like its fellow alkali metals
on the far left of the periodic table, lithium
has a single outer electron that it easily gives
up, says Jeff Sakamoto, Ph.D., a mechanical
engineering professor at Universit y of Mich-
igan who specializes in solid-state battery
research. “That creates a really high volt-42 January/February 2022