Atomic-Level Structure and Dynamic Evolutions in Cobalt-Free High-Performance Sodium-Ion Battery Cathode
Lead Research Organisation:
University of Cambridge
Department Name: Chemistry
Abstract
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 to
quantitatively 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.
quantitatively 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.
| Description | Co-chair of the UK's Battery Strategy Taskforce Committee, a Department for Business and Trade (DBT) advisory committee. |
| Geographic Reach | National |
| Policy Influence Type | Participation in a guidance/advisory committee |
| Impact | The committee advises DBT civil servants on the development of policy in the battery sector - from financing, to regulation to supply chain issues. While we (and specifically, I) commented on the report - https://assets.publishing.service.gov.uk/media/656ef4871104cf000dfa74f3/uk-battery-strategy.pdf - but since the report is produced by the govt. our names are not on it. |
| URL | https://www.gov.uk/government/news/government-holds-first-taskforce-for-the-uk-battery-strategy |
| Title | Development of a More Stable Mixed-Cation Cathode for Sodium-Ion Battery Applications |
| Description | We have demonstrated that a novel composition of a sodium-ion battery cathode, in a specific crystallographic phase, exhibits greater stability over battery cycling compared to other mixed-cation compositions. Using state-of-the-art solid-state NMR spectroscopy, which is central to our research group, we have uncovered key structural information and investigated the influence of electrochemical processes on these structures. |
| Type Of Material | Technology assay or reagent |
| Year Produced | 2024 |
| Provided To Others? | No |
| Impact | The development of this research method, particularly the use of state-of-the-art solid-state NMR spectroscopy, has provided critical insights into the structural and electrochemical behavior of sodium-ion battery cathodes. This has enabled a deeper understanding of material stability, which is essential for improving battery performance and longevity. The findings could contribute to the advancement of more efficient and sustainable energy storage solutions, with potential applications in next-generation battery technologies. |
| Description | P2/P3 Cathode Materials for Sodium-Ion Batteries |
| Organisation | University of St Andrews |
| Department | School of Chemistry St Andrews |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | We investigated the local chemical structure and dynamic properties of various biphasic sodium-layered transition metal oxide cathodes (e.g., P2/P3 or P2/O3) using advanced solid-state nuclear magnetic resonance (NMR) spectroscopy. High-speed magic-angle spinning (=50 kHz) was employed under both low and moderately high magnetic field conditions (4.7-11.7 T), along with variable-temperature experiments. The primary objective was determining whether phase separation or intergrowth occurs between the constituent phases. Additionally, NMR spectroscopy was utilized to quantify the extent of degradation products formed by comparing freshly synthesized materials with those exposed to ambient conditions over an extended period. |
| Collaborator Contribution | Our collaborators contributed to this study by synthesizing the sodium-layered transition metal oxide cathodes and performing extensive material characterization, including X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. Additionally, they investigated the electrochemical properties of the cathode materials by fabricating and testing coin cells. Their expertise in synthesis and electrochemical analysis complemented our solid-state NMR investigations, providing a comprehensive understanding of the structural and dynamic properties of these materials. |
| Impact | This collaboration has led to a manuscript currently in preparation, focusing on the structural and electrochemical properties of biphasic sodium-layered transition metal oxide cathodes. It is a multidisciplinary effort combining materials chemistry, electrochemistry, and advanced structural characterization techniques such as solid-state NMR spectroscopy, XRD, HRTEM, and Raman spectroscopy. The partnership has provided comprehensive insights into phase behavior, degradation mechanisms, and electrochemical performance, contributing to sodium-ion battery research. |
| Start Year | 2023 |
| Description | Chemistry Open Day & Cambridge Festival |
| Form Of Engagement Activity | Participation in an open day or visit at my research institution |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Every year, the Department of Chemistry at the University of Cambridge hosts this public engagement event, inviting everyone to put on a lab coat and safety specs to join in the fun of hands-on chemistry experiments. Over a hundred schoolchildren and their parents/guardians actively participated in various experiments demonstrating real-life scientific applications. My role was to showcase the use of different types of magnets and the "lemon juice battery." A superconducting "toy train" was used to demonstrate the principles behind magnetic levitation, similar to the mechanism used in high-speed maglev trains, which rely on cryogenic superconducting magnets. These superconducting magnets are also crucial in technologies such as nuclear magnetic resonance (NMR) spectroscopy and advanced battery research-both core aspects of this research proposal. The event successfully sparked curiosity and engagement, encouraging greater interest in chemistry and its practical applications. |
| Year(s) Of Engagement Activity | 2024 |
| URL | https://outreach.ch.cam.ac.uk/chemistry-open-day-cambridge-festival |