Development of operando NMR methods for the characterisation of next generation battery technologies'

开发用于表征下一代电池技术的操作核磁共振方法

• 批准号: 2746557
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2746557
• 关键词: Development; operando; NMR; methods; characterisation

This project falls within the EPSRC Physical Sciences and Energy research areas.The demand for energy storage devices has never been greater. Lithium ion batteries have played key role in the development of consumer electronics, due to their high energy densities, and they are a key technology in enabling the transition to greener energy sources, in particular the electrification of transport. Unfortunately a single technology is not suitable for all applications and current lithium ion batteries will not be able to meet the demands of other forms of transport, such as aviation and maritime applications - beyond lithium ion technologies are needed alongside new materials for lithium ion cells. The lithium-air battery offers the highest theoretical specific energy of any battery technology making it well suited to demanding applications. New technology that enables electrification of other parts of the transport network and supports the transition to renewables which will reduce carbon emissions and help meet climate change targets.To realise this potential we need to understand the chemistry and electrochemistry that underpins the operation of lithium-air cells and factors affecting performance. The Li-air battery consists of a lithium metal negative electrode and a porous positive electrode, separated by an organic electrolyte. On discharge, at the positive electrode, lithium peroxide is formed, which is oxidised on subsequent charging. The lithium air battery is known to undergo detrimental decomposition reactions during cycling, leading to unwanted side-products. Preventing the formation of these species is vital to realise the full potential.The project will involve developing an in-operando multinuclear benchtop nuclear magnetic resonance (NMR) methodology to understand the electrochemistry and parasitic reactions taking place in the lithium-air battery. Our understanding is limited due to lack of knowledge on how electrolytes change as a cell is cycled. Electrolytes will also play an important role in enabling the next generation of cathode materials for lithium ion cells. These anionic redox materials operate at high voltages, where electrolyte degradation is significant. Understanding the changes in battery materials as the cell is cycled is crucial to devise strategies to prevent decomposition and improve performance. Current techniques require cells to be dissembled before analysis. Benchtop NMR is a relatively new technique in the field and offers the chance to develop a new range of operando experiments to directly probe components as the cell is cycled. Other experimental techniques, such as electrochemistry, UV-Vis spectroscopy, diffraction and differential electrochemical mass spectrometry will be used to provide complementary data. The methodology developed in this project will be relevant to other storage technologies.The project is co-funded by Oxford Instruments as part of an iCASE studentship.

该项目福尔斯属于EPSRC物理科学和能源研究领域。对储能设备的需求从未如此之大。锂离子电池由于其高能量密度而在消费电子产品的发展中发挥了关键作用，并且它们是实现向更绿色能源过渡的关键技术，特别是运输电气化。不幸的是，单一的技术并不适合所有的应用，目前的锂离子电池将无法满足其他形式的运输需求，如航空和海事应用-除了锂离子技术之外，还需要新的锂离子电池材料。锂空气电池提供了任何电池技术中最高的理论比能量，使其非常适合苛刻的应用。新技术可以使交通网络的其他部分实现电气化，并支持向可再生能源的过渡，从而减少碳排放，帮助实现气候变化目标。为了实现这一潜力，我们需要了解支撑锂空气电池运行的化学和电化学以及影响性能的因素。锂空气电池由锂金属负极和多孔正极组成，由有机电解质隔开。在放电时，在正电极处形成过氧化锂，其在随后的充电中被氧化。已知锂空气电池在循环期间经历有害的分解反应，导致不需要的副产物。防止这些物种的形成对于充分发挥潜力至关重要。该项目将涉及开发一种操作中多核台式核磁共振（NMR）方法，以了解锂空气电池中发生的电化学和寄生反应。我们的理解是有限的，由于缺乏知识的电解质如何改变作为一个电池是循环。电解质也将在实现下一代锂离子电池阴极材料方面发挥重要作用。这些阴离子氧化还原材料在高电压下操作，其中电解质降解是显著的。了解电池材料在电池循环过程中的变化对于制定防止分解和提高性能的策略至关重要。目前的技术要求细胞在分析之前被分解。台式NMR是该领域中相对较新的技术，并提供了开发一系列新的操作实验的机会，以在电池循环时直接探测组分。其他实验技术，如电化学，紫外-可见光谱，衍射和微分电化学质谱将用于提供补充数据。该项目中开发的方法将与其他存储技术相关。该项目由牛津仪器公司共同资助，作为iCASE学生奖学金的一部分。