Nanofiber-based Novel Electrode Architecture for Lithium-Air batteries

主要研究者：Kalra，Vibha方案编号：1236466机构：德雷克塞尔大学标题：基于纳米纤维的新型电极结构的锂-空气电池尽管最近在最先进的锂离子电池方面取得了进展，但它们的能量和功率密度不足以用于运输应用。该项目将研究一种新型电池化学，即锂空气，其理论能量密度比锂离子电池高出近2个数量级。然而，在锂空气电池的承诺成为现实之前，需要克服的一个严峻挑战将成为这项工作的重点，那就是开发？纳米结构空气阴极这优化了所有反应物（氧气、Li+离子和电子）向活性催化剂表面的传输，并为电池放电过程中固体氧化锂产物的结合提供了足够的空间。该提案的具体目标是在一种新型的、分级有序的纳米纤维基架构中制造和研究工艺-结构-性能相关性，旨在开发用于锂空气电池的高效阴极。一个独特的三轴静电纺丝技术将被使用，这将允许核-壳架构，以实现良好控制的定向材料组装通过一个简单的合成过程。除了提供明确定义的多相反应表面之外，所提出的电极设计将表现出分级的两级孔结构;来自静电纺丝固有的纤维间间距的大孔和介孔，其将通过受控的纳米级材料组装在碳芯中产生。这种结构将有助于优化氧气质量传输和表面积，并提供足够的孔隙空间，用于掺入最大化放电潜力所需的固体放电产物。 由于所提出的架构的复杂性，PI？我们的方法是首先独立地理解核-壳结构的每个功能层中的静电纺丝行为和过程-结构相关性，然后利用这些知识来研究完整的架构。如果成功，这项工作将开发出比目前最先进的锂离子电池具有更高储能密度的电池。这种能力将使他们能够成功地在运输部门竞争，并实现令人满意的练习范围。此外，通过这项工作获得的材料加工，结构和电极设计的基础知识也将有利于超级电容器和其他电池化学。该项目将涉及一名博士研究生、几名本科生和K-12学生/教师，特别是女性和来自代表性不足的少数民族的学生/教师，通过讲习班、研究课程和实践研究经验，参与跨学科研究活动。

PI: Kalra, VibhaProposal Number: 1236466Institution: Drexel UniversityTitle: Nanofiber-based Novel Electrode Architecture for Lithium-Air batteries Despite recent advances in the state-of-the-art lithium ion batteries, their energy and power densities are insufficient for transportation applications. This project will examine a novel battery chemistry, namely, Lithium-air, which can exhibit a theoretical energy density of almost 2 orders of magnitude higher than lithium-ion batteries. However, before the promise of Li-air batteries can become a reality, a serious challenge that needs to be overcome and will be the focus of this work is the development of ?nanostructured air cathodes? that optimize transport of all reactants (oxygen, Li+ ions, and electrons) to the active catalyst surfaces and provide enough spaces for incorporation of solid lithium oxide products during battery discharge.The specific objective of this proposal is to fabricate and study process-structure-performance correlation in a novel, hierarchically-ordered nanofiber-based architecture with the aim to develop efficient cathodes for Li-air batteries. A unique triaxial electrospinning technique will be used that will allow core-shell architecture to achieve well-controlled directed material assembly via a simple synthesis procedure. In addition to providing well-defined multi-phase reaction surfaces, the proposed electrode design will exhibit a hierarchical two-level pore structure; macropores from inter-fiber spacing inherent to electrospinning and mesopores, which will be created in the carbon core via controlled nanoscale material assembly. This structure will help optimize oxygen mass transport and surface area and provide sufficient pore space for incorporation of solid discharge products necessary to maximize discharge potential. Owing to the complexity of the proposed architecture, PI?s approach is to first independently understand the electrospinning behavior and process- structure correlation in each of the functional layers of the core-shell nanofiber and then leverage these learnings to study the complete architecture. If successful, this work will develop batteries that possess significantly higher energy storage density than the current state-of-the-art Li-ion batteries. Such ability will allow them to successfully compete in the transportation sector and achieve a satisfactory driving range. In addition, the fundamental knowledge gained through this work on materials processing, structure and electrode design will also benefit supercapacitors and other battery chemistries. This project will involve 1 PhD graduate, several undergraduates and K-12 students/teachers, particularly females and those from under-represented minorities in interdisciplinary research activities via workshops, research-based course and hands-on research experiences.