SBIR 95-1 SOLICITATION
CHEMICALLY MODIFIED ELECTRODES FOR IMPROVED CAPACITY AND LIFE IN RECHARGEABLE LITHIUM BATTERIES
Oxides such as LiCoO2 have been used as the cathode in recently
commercialized rechargeable lithium batteries. However, these highly oxidizing
materials attack and decompose liquid electrolytes when fully charged, causing
severely shortened cell life and safety hazards. Current designs avoid this
problem using voltage limitation, which reduces the achievable energy density by
a factor of two. Another solution would be to use an oxidation-resistant polymer
electrolyte; however, polymer electrolytes have low conductivities, which limits
the discharge rate unacceptably.
State-of-the-art oxide cathode materials for rechargeable lithium batteries
will be chemically modified to improve their energy density and cycle life. The
innovation will combine the oxidation resistance of polymer electrolytes with the
high conductivity of liquid electrolytes, by chemically attaching an ultrathin
layer of polymer electrolyte to the oxide surface by silanization. This will
protect the electrolyte from degradation while adding minimally to cell
impedance, and enable a two-fold improvement in energy density.
New modified electrodes will be tested in lithium cells and compared to the
performance of conventional electrodes. The program will demonstrate that
chemically modified electrodes can be incorporated in lithium batteries which are
safe, have long cycle and shelf life, and energy density > 150 Whr/kg.
Potential Commercial Applications:
Reliable, high energy, high power rechargeable batteries would find a large
market in portable consumer products such as telephones, televisions, video
cameras, computers and hand-held tools.
Name and Address of Offeror:
3768 Hawkins Street, NE
Albuquerque, NM 87109-4511
Small Business Innovation Research Program (SBIR) &
Small Business Technology Transfer Program (STTR) Programs
Electronic Management System (EMS)
National Aeronautics and Space Administration (NASA)
The SBIR/STTR EMS site is maintained by Steve
Hu, Hughes STX.
For comments and questions, contact
Updated: Feb. 7, 1996