Paper published: Polyethylene oxide-Li6.5La3Zr1.5Ta0.5O12 hybrid electrodes: Lithium salt concentration and biopolymer blending

Yes, I am surprised myself that we are involved in publishing such a paper. It is the result of our participation in the grEEn project, a NRW Graduate School aiming to make batteries greener, coordinated by the Münster Electrochemical Energy Technology centre MEET. Max Linhorst is one of our two doctoral candidates involved in it, and he collaborated with Maike Wirtz in the group of Prof. Hans Kungl from the Institute of Energy and Climate Research – Fundamental Electrochemistry at the Forschungszentrum Jülich. Batteries are a fundamental requirement for a shift away from our current petrol-fuelled cars and economy, but today’s batteries are far from being environmentally benign. One possibility to improve the sustainability of batteries is the, at least partial, replacement of synthetic polymers by biopolymers. In this paper, Maike and Max demonstrate that 25% of the polyethylene oxide (PEO) in hybrid electrodes (consisting of a polymer and a ceramic electrolyte) can be replaced by chitosan mesylate or cellulose acetate, albeit leading to a reduced performance in terms of ionic conductivity. However, while cellulose acetate lowered the ionic conductivity by about three orders of magnitude, substitution with chitosan mesylate reduced ionic conductivity ‘only’ by a factor of ca. 5. Of course, even if we find a perfect chitosan for the task, there will never be enough of it to feed all the batteries that we will need. But perhaps, we can learn something for the design of greener batteries.