Assault and Batteries
Researchers at Sandia National Laboratories must hate batteries: They heat them to extreme temperatures, overcharge them, drive nails into them, and generally do whatever they can to destroy them.
The
torture tests are part
of the DOE-funded
FreedomCAR program
that is testing
lithium-ion batteries
for hybrid electricgasoline
vehicles and
plug-in hybrids.
Current hybrid vehicles
run on gasoline and
use nickel-metal hydride
batteries to store
energy for the electric
motor. FreedomCAR
hopes to replace those
batteries with lithiumion
versions that have
six times the energy
density of lead-acid
batteries and two to
three times the energy
density of nickel-metal
hydride batteries.
“Lithium-ion batteries
in laptops and
power tools have greatly improved
over the past few years,” says Peter
Roth, lead researcher for Sandia’s
FreedomCAR battery efforts. “In
fact, they have improved so much
that we expect to see them in hybrids
later this year and possibly
in short-range plug-in hybrids
within two years.”
The researchers test batteries to
determine when and how they can
fail or leak. They also study the
stability of the materials, flameretardance,
high-temperature integrity
of separators between the
cathode and anode, and other
thermophysical properties.
Roth says some of the newer
batteries, like the new lithium/
iron phosphate versions in hand-held power tools, are extremely
resilient and less reactive when
subjected to extreme conditions.
Industry experts predict that
plug-ins that can run 10 miles
using only electricity are two to
three years away while plug-ins
that can run 40 miles are three to
four years away.
The first hybrids using lithiumion
batteries will be on the market
later this year when Mercedes-
Benz launches the S400 BlueHybrid.
After that, it will launch the
S300 Bluetec Hybrid, a diesel car
with a lithium-ion battery. General
Motors plans to introduce a
40-mile plug-in hybrid electric
vehicle with lithium-ion batteries
in 2010.