Sarbajit Banerjee, Texas A&M University
A Multiscale Approach to Cathode Design Based on Mapping Intercalation Gradients within Individual Particles and across Particle Aggregates
Written by Aashutosh Mistry
A common belief in the lithium battery community is to go for nanoscale materials to combat mechanical stresses and to avail more reaction sites due to increased surface-to-volume ratio. Sarbajit Banerjee at Texas A&M University argues, using an extensive set of experimental data, that the fundamental lithium intercalation dynamics is sensitive to size at submicron length scales.
He used vanadium pentoxide (V2O5) as a workhorse electrode material for lithium intercalation. He employed x-ray radiation to identify various different phases of intercalated V2O5. From his experiments, Banerjee discovered that as particle size is reduced below a threshold dimension (tens of nanometers) the material starts demonstrating a combination of phases with different degrees of lithium intercalation. Afterwards, Banerjee worked with a network structure of V2O5 nanowires of different dimensions. The results reveal that the dynamical behavior of these networks depends strongly on interparticle interactions, and cannot be explained from studying individual particles alone.
Moving ahead, the fundamental understanding of such events would allow systematic reconfiguration of materials. For example, with the insights gained from traditional V2O5, they switched to a different phase—zeta V2O5, for which their preliminary results show superior functionality.