This project contributes new knowledge related to a microbial nanomachine-based manufacturing process for fabricating high-performance lithium-sulfur batteries. The novelty of this potentially-scalable and environmentally-friendly process is the use of microbial nanomachines that scavenge environmental pollutants to produce nanoscale materials. This award supports research to investigate sulfide oxidizing bacteria and cellulose bacteria to produce sulfur-containing nanoparticles and nanocellulose membranes, respectively, for use in high-performance lithium-sulfur batteries. The sulfur-containing nanoparticles are produced by sulfide oxidizing bacteria by harvesting environmental or industrial sulfide pollutants. The nanocellulose membrane is manufactured by cellulose bacteria through recycling certain agriculture or industry byproducts/wastes. The outcome of this research greatly impacts future high-performance battery technology, which benefits the U.S. economy and society. This convergent research involves biochemistry, material science and electrochemistry. Its multi-disciplinary approach trains the future advanced manufacturing workforce, fosters participation of women and underrepresented groups, and positively impacts STEM education.
The challenge of soluble lithium polysulfides shuttling and other problems must be solved to develop high-performance lithium-sulfur batteries. This calls for manufacturing processes that produce a sulfur cathode nanostructure, which can physically trap and chemically bind these polysulfides, and a functionalized battery separator as a second barrier to close off the shuttling path. In nature, sulfide oxidizing bacteria can oxidize sulfide pollutants into elemental sulfur nanoparticles and store them in their bodies. There are also bacteria which produce high-quality nanocellulose membranes suitable as a battery separator by harvesting agriculture byproducts. This project studies two processes; a sulfide oxidizing bacteria cultured to produce sulfur-containing nanoparticles used in sulfur cathodes and a bacterial cellulose fermentation process along with its ionic modification as the battery separator. When combined, these components work cooperatively in solving the polysulfides shuttling and other problems faced by the lithium-sulfur battery technology. The research involves the study of polysulfides shuttling retardation mechanism, process development, nanostructure control and tailoring, material characterization, and battery performance testing. Together they advance the understanding of generating rationally-designed nanostructures via the scalable nanomanufacturing process using microbial nanomachines to manufacture high-performance lithium-sulfur batteries.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
