STRESS-MODULATED DRIVING FORCE FOR LITHIATION REACTION IN HOLLOW NANO-SPHERICAL ANODES

ABSTRACTRecent experimental evidence on nano-particle and nano-wire silicon anodes showed an initial rapid velocity of reaction front at the initial stage of lithiation, followed by an apparent slowing or even halting of the reaction front propagation. This intriguing phenomenon is attributed to the lithiation-induced mechanical stresses across the reaction front which is believed to play an important role in the kinetics of reaction at the front. Here, through theoretical formulation, we presented a comprehensive study on lithiation-induced stress field and its contribution to the driving force of lithiation in hollow spherical anodes with different boundary conditions at the inner surface of the particle. Our results reveal that hollow spherical silicon anodes can be lithiated more easily than solid spherical silicon particles and thus may serve as an optimal design of high performance anodes of lithium-ion battery.