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Battery Materials

Today, rechargeable ion-batteries power everything from tablets and smartphones to electric cars. Our work focuses on understanding the fundamental crystallographic transformations during charge-discharge cycles of battery materials and how we can optimize performance through in-depth understanding of the structure of battery materials.  

There is currently a call for entirely different battery concepts designed for mobile purposes as well as stationary electricity storage e.g. in the power grid. The technological solutions to these challenges rely on development of the inorganic electrode materials inside ion-batteries (cathode and anode). They are responsible for the intercalation of alkali-ions which move in and out of the structure upon charge and discharge.

In the Iversen group, we develop ion-batteries by combining material synthesis with actual battery assembly into coin-cells (using the products). The coin-cells are subsequently tested and the material characteristics analyzed with respect to e.g. power density, number of cycles, internal electrical resistance, etc. All of this is further evaluated against the crystal structure of the materials through “live” (in situ) X-ray diffraction measurements during charge or discharge. These data are collected with an in-house diffractometer. They reveal the structural changes which occur with the migration of alkali ions in/out of the electrodes, and grant insight in the fundamental reasons behind the observed performance of the cells. This knowledge, in turn, leads to new synthesis attempts of improved materials and iteration as already described.

These experimental approaches are combined with a theoretical view of battery performance, namely computer simulation of alkali-ion migration pathways in the crystal lattice. Evaluation of these intercalation channels further improves the understanding of how and why battery performance is affected, especially when compared to the X-ray diffraction data mentioned above.

Material Examples

Click on the links below to find out more about the battery materials we have studied within the Iversen group.  

  MnO2    Li4Ti5O12  
  TiO2  SnO2  LiFePO4