STTR Phase II: Advanced Li-S Battery System for Unmanned Air Vehicles

该奖项全部或部分根据2021年美国救援计划法案（公法117-2）资助。小企业技术转移研究（STTR）项目的更广泛的影响/商业潜力包括减少美国在电池系统的生产和供应方面对外国来源材料的依赖。随着电动汽车数量的增加，人们越来越担心锂离子电池（LIB）材料的短缺。 锂硫（Li-S）电池使用更容易获得、成本更低且环境友好的硫。锂硫电池不需要使用硫酸或其他更有害的化学物质，这使得它们可以很容易地处理或回收。该项目将推进知识，以应对开发实用和商业上可行的（Li-S）电池的挑战。全球锂硫（Li-S）电池市场在2019年的价值为6.96亿美元，预计到2028年将达到66.86亿美元，预测期内的复合年增长率为29.6%。锂硫电池主要用于航空、汽车、电子设备和电力能源领域，因为对具有比其他电池类型更高能量密度的环保能源的需求不断增长。锂硫技术有可能提高美国电池制造的安全性。STTR第二阶段项目旨在解决实用锂硫电池开发面临的重要技术挑战。这些挑战包括有限的循环寿命、高自放电率和充电结束时的过热。这些被认为是由穿梭引起的，其中阴极物质扩散到阳极并直接与金属锂反应。将采用系统方法开发实用的高性能锂硫电池，重点关注：性能（高能量密度，大温度范围和相当长的循环寿命）;安全性;和可制造性。该项目结合了实验和电化学建模方法，以实现400-600 Wh/kg的锂硫电池; ≥200次循环;-20 ° C至60 ° C@1C。该项目将采用先进的三层多功能隔膜和锂金属阳极来解决与穿梭效应相关的问题。模拟工具将用于研究和优化锂硫电池的设计和性能。第二阶段的技术目标包括设计、制造和表征越来越大的软包电池（从50 mAh到500 mAh/1000 mAh）。该奖项反映了NSF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 award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The broader impact/commercial potential of this Small Business Technology Transfer Research (STTR) project includes reducing the US dependence on foreign-sourced materials for the production and supply of battery systems. There are increased concerns about the shortage of materials for lithium ion batteries (LIB) as the number of electric vehicles increases. Lithium Sulfur (Li-S) batteries use sulfur which is more readily available, lower cost, and environment-friendly. Li-S batteries do not require the use of sulfuric acid or other more harmful chemicals, which allows them to be disposed of easily or recycled. This project will advance knowledge in addressing challenges to the development of practical and commercially viable (Li-S) batteries. The Global Lithium-Sulfur (Li-S) Battery Market was valued at $696 Million in 2019 and is anticipated to reach $6,686 Million by 2028, with a CAGR of 29.6% during the forecast period. Li-S batteries are mainly used in aviation, automotive, electronic device, and power & energy sector due to the growing demand for environmentally friendly energy with higher energy density than other battery types. Li-S technology has potential to enhance safer battery manufacturing in the US.This STTR Phase II project proposes to address important technical challenges against the development of practical Li-S batteries. These challenges include limited cycle life, high self-discharge rates and over-heating at end of charge. These are thought to be caused by the shuttle, where cathode species diffuse to the anode and react directly with the metallic lithium. A system approach will be employed to develop practical high performance Li-S Cells by focusing on: Performance (high energy density, large temperature range, and considerable cycle life); safety; and manufacturability. The project combines experimental and electrochemical modeling approaches to achieve a Li-S cell with 400-600 Wh/kg; ≥200 cycles; - 20oC to 60oC @ 1C. The project will use advanced trilayer multifunctional separator and lithium metal anode to solve the problems associated with the shuttling effect. Simulation tools will be used to study and optimize the design and performance of the Li-S cells. The technical objectives for Phase 2 include the design, fabrication and characterization of progressively larger pouch cells (from 50 mAh to 500 mAh/1000 mAh). The development path will focus on achieving high energy density Li-S cells first and increasing the temperature range at a reasonable number of cycles.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.