Dr. Elisha Rejovitzky is a research fellow at the laboratory of mechanics of solids and materials at the department of mechanical engineering at MIT. He received his BSc (2008, summa cum laude) and PhD (2008-2013, direct track). His research during the PhD focused on modeling material fatigue and analyzing damage evolution. In the years 2006-2008 he worked in Elbit Systems on vibration analysis for performance and endurance of electro-optical systems.
In his current work at MIT, Dr. Rejovitzky studies the mechanical behavior of lithiation in Silicon. Silicon seems promising for use in electrodes of Li-ion batteries and can supply a very high energy capacity. During lithiation, Silicon undergoes large deformations (up to 270% volume change) and may get damaged and cracked. The diffusion of Lithium in crystalline silicon is accompanied by an amorphization of the Silicon.
A sharp diffusion front is developed, moves in preferred crystallographic directions, and results in complex anisotropy and large deformations. The research is focused on formulating a consistent model of this coupled process and implementing it in a finite element program.