Nanostructured Composite Electrodes for Lithium Batteries (Final Technical Report)
The objective of this study was to explore new ways to create nanostructured electrodes for rechargeable lithium batteries. Of particular interests are unique nanostructures created by electrochemical deposition, etching and combustion chemical vapor deposition (CCVD). Three-dimensional nanoporous Cu6Sn5 alloy has been successfully prepared using an electrochemical co-deposition process. The walls of the foam structure are highly-porous and consist of numerous small grains. This represents a novel way of creating porous structures that allow not only fast transport of gas and liquid but also rapid electrochemical reactions due to high surface area. The Cu6Sn5 samples display a reversible capacity of {approx}400 mAhg-1. Furthermore, these materials exhibit superior rate capability. At a current drain of 10 mA/cm2(20C rate), the obtainable capacity was more than 50% of the capacity at 0.5 mA/cm2 (1C rate). Highly open and porous SnO2 thin films with columnar structure were obtained on Si/SiO2/Au substrates by CCVD. The thickness was readily controlled by the deposition time, varying from 1 to 5 microns. The columnar grains were covered by nanoparticles less than 20 nm. These thin film electrodes exhibited substantially high specific capacity. The reversible specific capacity of {approx}3.3 mAH/cm2 was demonstrated for up to 80 cycles at a charge/discharge rate of 0.3 mA/cm2. When discharged at 0.9 mA/cm2, the capacity was about 2.1 mAH/cm2. Tin dioxide box beams or tubes with square or rectangular cross sections were synthesized using CCVD. The cross-sectional width of the SnO2 tubules was tunable from 50 nm to sub-micrometer depending on synthesis temperature. The tubes are readily aligned in the direction perpendicular to the substrate surface to form tube arrays. Silicon wafers were electrochemically etched to produce porous silicon (PS) with honeycomb-type channels and nanoporous walls. The diameters of the channels are about 1 to 3 microns and the depth of the channels can be up to 100 microns. We have successfully used the PS as a matrix for Si-Li-based alloy. Other component(s) can be incorporated into the PS either by an electroless metallization or by kinetically controlled vapor deposition.
- Research Organization:
- Georgia Institute of Technology, Atlanta, GA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- FG02-01ER15220
- OSTI ID:
- 896312
- Report Number(s):
- DOE/ER/15220-1; DE-FG02-01ER15220; GT project No. E18-A05; TRN: US200709%%480
- Country of Publication:
- United States
- Language:
- English
Similar Records
Scalable Synthesis of Defect Abundant Si Nanorods for High-Performance Li-Ion Battery Anodes
Mesoporous CNT@TiO2-C Nanocable with Extremely Durable High Rate Capability for Lithium-Ion Battery Anodes