34
Low-Cost
Nanoporous Sol Gel Separators for Lithium-Based Batteries--Optodot
Corporation, 214 Lincoln Street, Suite 305, Allston, MA
02134-1348; 617-562-0800, www.optodot.com
Dr.
Steven A. Carlson, Principal Investigator,
Dr.
Steven A. Carlson, Business Official,
DOE
Grant No. DE-FG02-02ER83542
Amount:
$577,103
Lithium-based
batteries for vehicles need to be longer lasting, faster recharging, able to
deliver high power pulses, safer, lower in cost, and have higher energy density.
However, the commercial microporous plastic polymer separators used in
these batteries are too expensive and are very limited in their ability to
provide these needed performance improvements.
This project will develop nanoporous sol gel coatings as a new type of
separator that can be coated from a water-based solution at less than one-half
the cost per square meter of commercial plastic separators.
The non-flammable, ionic, and ultra-thin properties of the sol gel
separators would allow major improvements in the safety, recharging and
discharging speeds, lifetime, and energy density of lithium-based batteries.
In Phase I, tough but very flexible 8-micron-thick sol gel separators
were made and showed porosities of 45%. A
manufacturing process, which involved sol gel coating on a smooth substrate and
then delaminating the coating from the substrate to form a free standing sol gel
separator, was demonstrated. In
Phase II, the mechanical properties of the 8-micron-thick sol gel separators
will be optimized by determining the amount and type of crosslinked polymers to
add. The interfacial surfaces
between the sol gel separator and the anode and cathode layers will be designed
and tested, first in lithium-ion batteries and then in lithium-sulfur batteries.
8-micron-thick sol gel separators will be made on machine coating
equipment using a low cost coating/delamination process.
Commercial Applications and Other
Benefits
as described by awardee: Besides
providing separators for lithium-based batteries for vehicles, sol gel
separators could be used for other battery applications such as mobile computers
and cell phones, as separator membranes for fuel cells, as ultrafiltration
membranes for purifying water, as dye-sensitized sol gel coatings for solar
splitting of water or methanol to produce hydrogen fuel, and as photo-quality
ink jet digital printing materials.