Martin Mansson

Abstract:

While Li-ion batteries are considered the main candidate for mobile energy storage applications, compounds based on lithium's heavier cousin, sodium (Na) have recently started to receive a lot of attention. One reason is that our Li-reserves are limited and to realize future electric vehicles we might have to reconsider the Li-ion technology. Na has indeed many advantages over Li e.g. Na is one of the most abundant elements in nature (earth's crust as well as in normal seawater of our great oceans), which makes it about 5 times cheaper than Li. Further, Na-ion batteries can also be much less toxic and easier to recycle. In many ways the NaxCoO2 compound is a Na-analog of the most common Li-ion battery electrode material LixCoO2. Hence, understanding Na-ion diffusion mechanisms in NaxCoO2 would seem a logical first step. In this talk I will show that neutron scattering is a crucial technique for the understanding of these materials. I will also summarize our recent results that reveal how the ion-diffusion process is intrinsically linked to a series of subtle structural transitions along with novel and functional possibilities for tuning battery performance using lattice-strains.