EAGER/GOALI: 3D Printing of Nanostructured Battery Electrodes

这项探索性研究早期概念资助（EAGER）和工业学术联络资助机会（GOALI）资金将探索将3D打印和纳米级纤维静电纺丝相结合的可行性，以改善电池电极。熔融沉积建模（FDM）是一种3D打印，通过在预先确定的路径逐层熔化，挤压和沉积热塑性聚合物长丝来创建三维物体。FDM工艺的一个限制是粗糙的特征尺寸（50-400微米）。静电纺丝是一种独特的纳米材料制造技术，可以连续生产纳米级纤维，但对其精确放置的控制非常有限。静电纺丝工艺本质上与卷对卷加工兼容，并且潜在地与3D打印兼容。这项研究将探索将3D打印和静电纺丝这两个概念结合起来的可行性，创造一种新的、有潜在影响的3D纳米打印类型。该团队将使用实验和计算模拟相结合的方法来测试电场对纳米纤维空间沉积的影响。这一发现可能会影响能源、医疗保健和国家安全领域高性能材料的制造能力。将支持一名研究生和几名本科生进行学术和工业研究。该项目的具体目标是建立一个双喷嘴三维静电纺丝平台，使聚合物导电主体和富硫共聚物活性材料在预定路径上同时进行纳米挤出。最终目标是为锂硫电池打印3D阴极，在多个长度尺度上显示尺寸精度。虽然多种功能材料的重叠挤压将允许纳米级接触以增强电化学性能（反应动力学，电导率和活性材料利用率），但3D打印的设计自由度将使纳米纤维定位能够精确地进行x-y-z控制，以定制大块宏观特性，如孔隙率和体积密度，这是商业应用的重要考虑因素。基于有限元的COMSOL模拟将用于预测电势分布作为各种相关工艺/设备参数的函数。模拟将与实验相结合，目的是建立设备/工艺参数、电场分布、纤维直径和空间沉积控制之间的相关性。研究的最终目的是与工业伙伴合作，研究基本的电化学行为、电池组装、电池测试以及死后材料和反应物/产品表征。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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.