Interfaces and interphases in in operandi Li-ion batteries

Maria Hahlin, Molecular and Condensed Matter Physics, was granted 3.32 million SEK for the project “Interfaces and interphases in in operandi Li-ion batteries” from the Swedish Research Council for the period 2016-2020.

Project description

The main focus of the project is developing a new method for real time studies of the interface formation processes in Li-ion batteries; in operandi ambient pressure photoelectron spectroscopy (APPES). The energy conversion between chemical and electrical energy in the Li-ion battery occur through redox reaction at the electrode surfaces.

The reactions are complex and lead to the build up of functional interphases between the electrodes and the electrolyte that govern properties such as discharge, safety, and long-term stability of the battery. The project targets the formation processes of the functional interphases on electrodes from all major classes of anodes; intercalation (Li4Ti5O12 and Graphite), alloying (Si) and conversion material (Fe2O3).

Specific focus is placed on the composition, function and control of the site for interphase formation and energy conversion; the buried interface between the functional interphase and the active electrode material. Moreover, the surface and bulk properties of the common electrolytes (Li-salts combined with carbonate based solvents) will be characterized and its stability during APPES measurement evaluated. The method development will make a strong contribution to the field of battery research, and is also expected to benefit related research fields targeting chemical reactions at a solid/liquid interface, e.g. catalysis, corrosion.