Lithium Plating on Graphite Electrodes in Lithium-Ion Batteries

Fast charging of lithium-ion batteries is a critical advancement in achieving more efficient and sustainable energy storage, particularly in electric vehicles. However, fast charging often leads to lithium plating, significantly impacting battery performance and longevity. While it is essential to reduce the amount of lithium plating, characterization of lithium plating is challenging due to high sensitivity of lithium to oxygen and water, small feature sizes, and the complex morphology of the porous electrode and the deposits (dendrites with solid-electrolyte interphase, SEI). Consequently, understanding the mechanism of lithium plating and SEI's influence on it remains elusive. In our study, we utilize operando atomic force microscopy (operando-AFM) to investigate the dynamic behaviors during lithium plating and stripping on graphite nanoplatelets. This technique allows real-time, nanoscale observation of lithium plating and stripping, providing insights into lithium nucleation, growth, and distribution on the anode surface. Notably, we observe graphite exfoliation during plating and stripping, indicating the loss of active materials and its implications for battery capacity and cycling stability. Additionally, our research explores the interaction between SEI and lithium plating. Understanding how SEI influences lithium plating dynamics is essential for developing strategies to optimize fast charging capabilities. By gaining insights from our investigations, we aim to inform the design of electrode materials, artificial SEI materials, and electrolyte additives that promote and facilitate fast charging in lithium-ion batteries. These strategies hold promise for enhancing battery safety, reliability, and overall performance, thereby accelerating the adoption of electric vehicles and other energy-intensive applications.