Operando pair distribution function measurements of silicon anodes

Silicon has approximately 10 times the capacity of the state-of-the-art anode material for lithium ion batteries (LIBs). To fully utilise the charge capacity of Si, it is crucial to understand why it loses capacity so quickly when the battery is put through cycles of charge and discharge, and why nanosizing of the Si is effective in extending its cycle life. The best way to gain information about the structural changes during cycling which cause deactivation is by an operando study in a working battery. We aim use total X-ray scattering to obtain the pair distribution functions (PDFs) of working nano-Si anodes. Previous studies of crystalline Si have given some insight in the structural mechanics of cycling, but do not give clean enough data. To mitigate this, we have developed a new operando battery cell. This will then give information about the structural changes of Si combined with electrochemical data.