Atomic-Level Structure and Dynamic Evolutions in Cobalt-Free High-Performance Sodium-Ion Battery Cathode

无钴高性能钠离子电池正极的原子级结构和动态演化

• 批准号: EP/Y024958/1
• 负责人: Clare Grey
• 金额: $ 23.84万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY024958%2F1
• 关键词: Atomic; Level; Structure; Dynamic; Evolutions

Sodium-ion batteries (SIBs) have the potential to emerge as a cost-effective and more sustainable alternative to conventional lithium-ion batteries (LIBs). While SIBs still suffer from lower performances and long-term cyclability because their limitation has not received much attention in comparison to their Li-ion counterparts. Like LIBs, the performance of SIBs relies heavily on the cathode materials; however, performance improvements have been primarily driven so far by trial-and-error efforts because of the lack of understanding of their atomic-level microscopic structure, ion dynamics as well as degradation mechanisms. To address these identified challenges associated with SIB cathodes, the proposed research will use a multi-scale and complementary material characterization approach, including state-of-the-art solid-state nuclear magnetic resonance (SSNMR) spectroscopic techniques, to undertake a thorough investigation of biphasic NaxTMO2 (x = 0 to 1, and TM = transition metal ion) cathodes, which, as reported in recent literature, exhibit better stability and electrochemical performance. Here, ex-situ and operando SSNMR spectroscopy will be utilized extensively toquantitatively deconvolute the atomic-level microscopic structure and ion dynamics mechanism of biphasic NaxTMO2 cathodes; the information gained will ultimately be correlated with the macroscopic electrochemical performance of the SIB battery devices. SSNMR spectroscopy will assist to unravel the presence or absence either of phase-segregation, nanodomains, or intergrowth formation taking place between two phases of biphasic NaxTMO2 and how they affect the battery performance. In summary, this proposed research will provide an exclusive understanding of the macroscopic electrochemical properties that directly correlate with the real-time microscopic atomic-level structural and ion dynamic changes of these newly identified biphasic NaxTMO2 cathodes for emerging SIB technology.

钠离子电池（SIB）有潜力成为传统锂离子电池（LIB）的一种经济高效、更可持续的替代品。虽然 SIB 仍然面临性能和长期循环性能较低的问题，因为与锂离子电池相比，它们的局限性并未受到太多关注。与LIB一样，SIB的性能很大程度上取决于正极材料。然而，迄今为止，由于缺乏对其原子级微观结构、离子动力学以及降解机制的了解，性能改进主要是通过反复试验来推动的。为了解决与 SIB 阴极相关的这些已确定的挑战，拟议的研究将使用多尺度和互补的材料表征方法，包括最先进的固态核磁共振 (SSNMR) 光谱技术，进行彻底的调查双相 NaxTMO2（x = 0 到 1，TM = 过渡金属离子）阴极，正如最近文献报道的那样，它表现出更好的稳定性和电化学性能。在这里，非原位和操作 SSNMR 光谱将被广泛用于定量解卷积双相 NaxTMO2 阴极的原子级微观结构和离子动力学机制；获得的信息最终将与SIB电池装置的宏观电化学性能相关。 SSNMR 光谱将有助于揭示双相 NaxTMO2 两相之间是否存在相分离、纳米域或共生形成，以及它们如何影响电池性能。总之，这项拟议的研究将为新兴 SIB 技术提供对这些新发现的双相 NaxTMO2 阴极的宏观电化学特性的独家理解，这些电化学特性与实时微观原子级结构和离子动态变化直接相关。