Battery materials: How many needles in the haystack?
Benedicte Vertruyen, Jérôme Bodart, Caroline Piffet, Nicolas Eshraghi, Audrey Schrijnemakers, Abdelfattah Mahmoud, Frédéric Boschini.
GREENMAT, CESAM research unit, University of Liege, 4000 Liège, Belgium.
The search for better battery materials can follow many different routes. Looking for brand-new compounds has always been a high-risk approach, which can now be assisted by machine-learning and high-throughput methods. A less adventurous strategy relies on the critical review of existing compounds in crystallographic databases in order to identify possible candidates, e.g. for « beyond Li » technologies. Since electrode performance has been repeatedly shown to be very much influenced by the electrode architecture, the exploration of alternative syntheses or processing methods is a highly popular route, with possible serendipitous discoveries along the way. Innovation in battery materials can also come from a shift to more sustainable source materials.
In this talk I will illustrate some of these strategies with three examples from our recent work. (1) We developed an aqueous solution route for the synthesis of the K3V(PO4)2 phase first reported in 1991 in order to investigate its properties as a positive electrode material in a K-ion battery. (2) While studying the formation of Na2Ti3O7 from a spray-dried mixture of Na2CO3 and TiO2, we identified an intermediate phase with a structure similar but not identical to that of Na2Ti6O13. (3) We developed a recovery route for the silicon from end-of-life photovoltaic panels and integrate it into high-capacity negative electrodes for Li-ion batteries.
Benedicte Vertruyen is currently Professor at the Department of Chemistry of the University of Liege. In 2003, she obtained a PhD at University of Liege for a research work focusing on the influence of microstructure on the magnetoresistivity of manganite oxides. As a post-doctoral researcher, she was involved in several research projects and international collaborations on different types of materials, developing her expertise in X-ray diffraction of polycrystalline materials. Her current research interests include the crystal chemistry of functional oxides and the synthesis of these materials as powders or thin films through solution routes, preferably aqueous.