This EArly-concept Grant for Exploratory Research (EAGER) and Grant Opportunities for Academic Liaison with Industry (GOALI) funding will explore the feasibility of combining 3D printing and nanoscale fiber electrospinning to enable improved battery electrodes. Fusion Deposition Modeling (FDM) is a type of 3D printing that creates a three-dimensional object by melting, extruding and depositing a thermoplastic polymer filament in a pre-determined path layer-by-layer. One limitation of the FDM process is the coarse feature size (50-400 microns). Electrospinning is a unique nanomaterial fabrication technique that continuously produces nanoscale fibers but with very limited control over their exact placement. The electrospinning process is inherently compatible with roll-to-roll processing and potentially compatible with 3D printing. This research will explore the feasibility of marrying the two concepts of 3D printing and electrospinning, creating a new and potentially impactful type of 3D nanoprinting. The team will use a combination of experiments and computational simulations to test the effect of electric field on the spatial deposition of nanofibers. The discovery could impact manufacturing capabilities of high performance materials for applications in energy, healthcare and national security. One graduate and several undergraduate students will be supported to conduct academic and industrial research.
The specific aim of this project is to build a dual-nozzle 3D electrospinning platform to enable simultaneous nano-extrusion of polymeric conductive host and sulfur-rich copolymer active material in a pre-defined path. The ultimate aim is to print 3D cathodes for Lithium-Sulfur batteries that exhibit dimensional accuracy at multiple length scales. While the overlapping extrusion of multiple functional materials will allow nanoscale contact for enhanced electrochemical performance (reaction kinetics, conductivity, and active material utilization), the design freedom of 3D printing will enable precise x-y-z control over nanofiber positioning for tailoring bulk macroscale properties such as porosity and volumetric density - important considerations for commercial applications. Finite element-based COMSOL simulations will be used to predict the electric potential distribution as a function of various relevant process/equipment parameters. The simulations will be integrated with experiments with the aim to establish correlations between equipment/process parameters, electric field distribution, fiber diameter and spatial deposition control. The final aim of the research will be to study the fundamental electrochemical behavior, battery assembly, battery testing and post mortem material and reactant/product characterization in collaboration with the industrial partner.
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.