NASA SBIR 2002 Solicitation


PROPOSAL NUMBER:02-II E2.06-8468 (For NASA Use Only - Chron: 023531 )
SUBTOPIC TITLE: Storage and Energy Conversion
PROPOSAL TITLE: High energy density Li-ion polymer batteries with nanocomposite cathodes

SMALL BUSINESS CONCERN: (Firm Name, Mail Address, City/State/ZIP, Phone)
NEI Corporation
201 Circle Drive North, Suite 102-103
Piscataway , NJ   08854 - 3908
(732 ) 868 - 1906

PRINCIPAL INVESTIGATOR/PROJECT MANAGER: (Name, E-mail, Mail Address, City/State/ZIP, Phone)
Amit Singhal
201 Circle Drive, Suite 102-103
Piscataway , NJ   08854 - 3908
(732 ) 868 - 1906

The energy density and the average operating voltage of Li-ion batteries can be enhanced by utilizing new cathode chemistries that have significantly higher capacity and higher open circuit voltage than those of start-of-the-art LiCoO2 cathode. The proposed program focuses on developing novel nanocomposites with a theoretical energy density of ~ 800 Wh/kg, which is more than 60% higher than that of the practical energy density of LiCoO2. In Phase I, we developed a process of producing nanocomposite cathode powders. The crystallite size of particles was in the range of 50 ? 300 nm. It was demonstrated that cathodes made of the nanocomposite powder were electrochemically active and exhibited high first charge capacity, > 85% of the theoretical capacity. Working with rechargeable Li-ion battery manufacturers and leading researchers, we will demonstrate that it is possible to produce stable and high energy density nanocomposite cathodes by manipulating the structure and the composition. Additionally, we will fabricate prototype Li-ion polymer cells consisting of cathodes made of the nanocomposite powders. Processing methods will be developed for producing large cathode tapes with nanostructured powders. The powder synthesis process will be optimized for producing kilogram quantities. The overall goal of the Phase II program is to achieve Li-ion polymer cells with an energy density of ~ 200 Wh/kg for a large number of discharge-charge cycles (~ 1000) and an average voltage of > 4.4 V.

Rechargeable Li-ion polymer batteries are becoming attractive for several military and space applications. These batteries can potentially replace Ni-MH batteries, which are being used for several space applications, including supplement battery pack (called Areba rechargeable battery pack) to power astronaut?s various accessories during Extravehicular Activities (EVAs), and Avionic batteries for the Crew Return Vehicle, X-38. Replacing Ni-MH batteries with high energy density Li-ion batteries will reduce the total number of cells that need to be connected in series as well as in parallel in order to produce a battery pack with a specific output voltage and capacity (Ah). This will reduce the weight of the battery pack. Further, high energy density Li-ion batteries (270V, 200 Ah) can also be used to power the pump for the hydraulic system in a space shuttle. Presently, a hydrogen turbine is used to power the pump; and high voltage battery technologies are being sought to replace the hydrogen turbine.

Secondary Li-ion polymer batteries are also the system of choice for several consumer applications, such as portable consumer electronics, wireless communication devices and implantable medical devices as well. Smaller and thinner cellular telephones and notebook computers, and emerging portable products such as, personal data assistants and palmtop computers, have created an immediate need for developing advanced rechargeable Li-ion batteries with high energy densities and longer run times. Because of their high current drain requirement, several implantable devices such as, ventricular assist devices (LVAD), implantable hearing assist devices, and some neurostimulators, need secondary batteries. Li?ion rechargeable batteries are being developed for use in both the implantable and the external battery systems for these devices. Therefore, there is an immediate need to significantly increase the energy density of Li-ion batteries.

Form Printed on 10-03-03 11:34