Collaborative Research: Engineering the Chemistry at Solid-Solid Interfaces of Li-O2 Battery Cathodes

合作研究：锂氧气电池正极固-固界面化学工程

• 批准号: 1935581
• 负责人: Eranda Nikolla
• 金额: $ 29.64万
• 依托单位: Wayne State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2023-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1935581&HistoricalAwards=false
• 关键词: Collaborative; Research; Engineering; Chemistry; Solid

Lithium-oxygen batteries potentially could have energy storage capacities that rival gasoline fuel, but there remains much fundamental scientific knowledge to learn about these batteries before the technology can be commercialized. In particular, some of the chemical products formed during the operation of the batteries can slowly degrade and poison the materials, leading to performance losses over extended periods of operation. This research project seeks to overcome these problems by exploring a class of inexpensive, mixed metal oxide electrocatalysts that may alter the chemistry of lithium-oxygen batteries. This project aims to develop a framework to engineer the chemistry of lithium-oxygen batteries, which are a potential next-generation energy storage device, and to improve their performance. The studies combine advanced characterization methods and theoretical calculations to determine how the properties of the oxide surfaces influence the products that are produced on lithium-oxygen electrodes. These insights will be leveraged to develop design principles that will aide in identifying oxide electrocatalysts that improve battery cell performance. The researchers involved in this project will partner with local K-12 schools to involve economically disadvantaged students with the proposed research through summer internships and student exchanges. They aim to inspire the students to pursue careers in science and engineering. A fundamental understanding of the reactions occurring at solid-solid interfaces is critical for the development of next-generation energy storage devices, such as lithium-oxygen batteries. Lithium-oxygen batteries have attracted significant interest in recent years due to their exceptionally high theoretical energy density. If even 15% of this energy density is achieved, then it would equal the value of gasoline, making lithium-oxygen batteries with driving ranges of up to 500 miles per charge commercially viable. While this technology is very attractive, numerous technical challenges need to be overcome before its widespread adoption is possible. Some of these challenges include: (i) insolubility of the solid discharge reaction products, leading to clogging of the cathode and eventually resulting battery cell death; (ii) low roundtrip (discharge-charge cycle) efficiency due to high charge overpotentials to dissociate the main discharge reaction product, lithium peroxide; and (iii) instability of electrolytes at high overpotentials. This research project seeks to alleviate these issues by designing solid-solid interfaces at the cathode of lithium-oxygen batteries that selectively stabilize lithium-deficient discharge products that are not insulating and can be dissociated at reasonable overpotentials. The researchers will apply a combined experimental and theoretical approach to study the chemistry at these solid-solid interfaces with the aim of designing materials that can selectivity tune the discharge product distribution such that it leads to improved battery performance. In particular, the work will involve a combination of advanced characterization studies and theoretical calculations to determine how the elemental composition, electronic properties, and symmetry of the oxide surface influence the discharge product distribution in lithium-oxygen cathodes. The studies will elucidate the effect of the global oxide crystal structure on the discharge product formation and lead to the development of design principles for identifying oxide electrocatalysts that are highly selective towards the formation of lithium-deficient oxide discharge products and therefore exhibit low charge overpotentials.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.

锂氧电池可能具有与汽油燃料相媲美的储能能力，但在该技术商业化之前，仍有许多基础科学知识需要了解。特别是，在电池运行期间形成的一些化学产品会慢慢降解和毒化材料，导致长时间运行时的性能损失。这项研究项目试图通过探索一种廉价的混合金属氧化物电催化剂来克服这些问题，这种催化剂可能会改变锂氧电池的化学结构。该项目旨在开发一种框架来设计锂氧电池的化学结构，并提高其性能。锂氧电池是一种潜在的下一代储能设备。这些研究结合了先进的表征方法和理论计算，以确定氧化物表面的性质如何影响锂氧电极上产生的产品。这些洞察力将被用来开发设计原则，帮助识别提高电池性能的氧化物电催化剂。参与该项目的研究人员将与当地K-12学校合作，通过暑期实习和学生交流，让经济困难的学生参与拟议的研究。他们的目标是激励学生在科学和工程领域追求职业生涯。对固体-固体界面上发生的反应有一个基本的了解，这对于开发下一代储能设备，如锂氧电池至关重要。近年来，锂氧电池因其极高的理论能量密度而引起了人们的极大兴趣。如果达到这种能量密度的15%，就相当于汽油的价值，这将使每次充电续航里程高达500英里的锂氧电池在商业上可行。虽然这项技术非常有吸引力，但在它得到广泛采用之前，需要克服许多技术挑战。其中一些挑战包括：(I)固体放电反应产物的不溶性，导致阴极堵塞，最终导致电池死亡；(Ii)由于高充电过电位而导致的往返(放电-充电循环)效率低，以解离主要放电反应产物过氧化锂；以及(Iii)高过电位下电解液的不稳定。本研究项目旨在通过在锂氧电池的正极设计固体-固体界面来缓解这些问题，该界面可以选择性地稳定不绝缘且可以在合理的过电位下解离的缺锂放电产品。研究人员将采用实验和理论相结合的方法来研究这些固体-固体界面的化学成分，目的是设计能够选择性地调整放电产物分布的材料，从而提高电池性能。特别是，这项工作将涉及先进的表征研究和理论计算相结合，以确定元素组成、电子性质和氧化物表面的对称性如何影响锂氧阴极中的放电产物分布。这些研究将阐明全球氧化物晶体结构对放电产品形成的影响，并导致开发设计原则来识别氧化物电催化剂，这些氧化物电催化剂对形成缺锂氧化物放电产品具有高度选择性，因此显示出低充电过电位。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。