The development of high-energy, long-lifetime energy storage systems based on rechargeable batteries relies on our ability to control charge storage and degradation processes in the bulk of the electrode materials and at the electrode-electrolyte interface. NMR spectroscopy is exceptionally suited to follow the electrochemical and chemical processes in the bulk of the electrodes and electrolyte, providing atomic scale structural insight into the charge storage mechanisms and ion transport properties.
However, what happens at the interfaces, i.e. the crucial processes governing charge transport between the electrode and the electrolyte, is much harder to study. These processes involve the formation of thin, heterogeneous and disordered interphases. While NMR is in principal an excellent approach for probing disordered phases, its low sensitivity presents an enormous challenge in the detection of interfacial processes.
I will describe recent approaches to overcome this limitation by the use of Dynamic Nuclear Polarization (DNP). In DNP, the large electron spin polarization is used to boost the sensitivity of NMR spectroscopy by orders of magnitude. I will show how we can use this approach to detect the solid-electrolyte interphase (SEI), as well as the electrode’s bulk, with unprecedented sensitivity. Furthermore, I will discuss the feasibility of using magnetic resonance methods to correlate the SEI composition with its ion transport properties – the least understood aspect of the SEI, which is essential for developing long-lasting energy storage systems.
Michal Leskes is a senior scientist (assistant professor) at the department of materials and interfaces at the Weizmann institute of Science. She completed a BSc in chemistry summa cum laude at Tel Aviv University (2004) followed by a PhD in chemical physics at the Weizmann Institute of Science (2010).
She was a postdoctoral research associate at the University of Cambridge, UK (2011-2015). Her research focus is on correlating the structure and properties of energy storage and conversion materials and the development of high sensitivity magnetic resonance approaches for probing the bulk and interface of functional materials.
She received the J. F. Kennedy Prize for her PhD (2010), the Award of Excellence by the National Postdoctoral Award Program for Advancing Women in Science (2011), a Marie Curie Postdoctoral Fellowship (2012-2013) and the Yigal Alon fellowship from the Israeli council of higher education (2015-2018).