ترکیب میکروسکوپ الکترونی عبوری برودتی و محاسبات dft برای درک مسیر و انرژی نفوذ یون های لیتیم در نانو لایه sei باتری های لیتیمی

The solid-electrolyte interphase (sei) is a key factor in determining platted lithium morphology, power capability, cycle life, and safety of lithium batteries. although the chemistry, structure, and the formation of the sei layer is extensively studied, lithium ions diffusion mechanisms across the sei are not fully understood. herein, cryo-transmission electron microscopy (cryo-tem) combined with first principles density functional theory (dft) calculations are used to examine the lithium ions diffusion coefficients and pathways and the corresponding energetics within the polycrystalline sei with a focus on the ions diffusion through the grain boundaries (gbs) formed by li2o, lif, and li2co3 nanocrystals. our findings shows that lif/li2co3 gb exhibit the highest diffusion rate and the lowest energy barrier for lithium ions. the li2o/li2co3 gb is particularly found to be susceptible to li dendrite formation.