Lithiation of Tin Nanoneedles Investigated by in-situ TEM

In the search for a better anode material for lithium-ion batteries (LIBs), elemental Sn has generated considerable interest due to its high theoretical specific capacity of 994 mAh/g. However, neither bulk material nor continuous films of Sn are useful in practice because the large volume change that occurs during lithiation and delithiation causes mechanical failure of the electrode [1]. Arrays of one-dimensional Sn nanostructures have been used to circumvent this, as they incorporate enough empty space into the structure to accommodate the expansion and contraction that occur during cycling. This reduces the associated stresses and prevents mechanical failure [2]. While most processes used to create nanostructures are slow and resource-intensive, a template-free, low-temperature, industry-scalable method for preparing nanostructured tin anodes has been reported [3]. The present study reports on the microstructural changes that these materials undergo during lithiation and delithiation as observed through in-situ experiments in the transmission electron microscope (TEM).