The critical role of interfaces in advanced Li-ion battery technology: A comprehensive review

The passivation layer in lithium-ion batteries (LIBs), commonly known as the Solid Electrolyte Interphase (SEI) layer, is crucial for their functionality and longevity. This layer forms on the anode during initial charging to avoid ongoing electrolyte decomposition and stabilize the anode-electrolyte interface. However, repeated charging and discharging can destabilize the SEI, thereby increasing internal resistance and reducing capacity. Similarly, the Cathode Electrolyte Interphase (CEI) layer is crucial for the performance, safety, and durability of LIBs. The formation, stability, and evolution of the SEI and CEI layers are critical for the efficiency and lifespan of LIBs. Research has focused on optimizing these interphases through advanced materials , interface modifications, and improved electrolyte formulations. Enhancing our understanding of SEI and CEI formation and degradation can lead to significant advancements in LIB performance, lifespan, and safety, thereby satisfying the demands for high-performance power storage in electronic appliances and electric vehicles. Future innovations promise to improve energy density , charge-discharge efficiency, and overall battery reliability.