The generation and evolutional behavior of the solid-electrolyte interphase (SEI) fatally dictate the performance of working anodes, especially lithium (Li) anodes. In this Opinion, we describe the critical rationale in understanding competitive SEI formation on a working Li metal anode. First, the fundamentals that determine the competitive SEI-forming reactions at the Li/electrolyte interface are analyzed. Moreover, we elucidate the kinetic competition between SEI growth and Li deposition in the case of exposure to fresh Li surfaces during the Li electroplating process. Several important factors involving electrolyte formulation, current density, and temperature that can intrinsically modulate the kinetic competition are comprehensively summarized. Finally, future research trends regarding dynamic SEI formation and its correlation with the manner of Li electroplating are addressed.

固体电解质相间（SEI）的生成和演化行为决定了工作阳极，特别是锂（Li）阳极的性能。在本《意见》中，我们描述了理解可工作的锂金属阳极上竞争性SEI形成的关键原理。首先，分析了决定锂/电解质界面竞争性SEI形成反应的基础。此外，我们阐明了在锂电镀过程中暴露于新鲜锂表面的情况下，SEI生长与锂沉积之间的动力学竞争。总结了涉及电解质配方，电流密度和温度的许多重要因素，这些因素可以固有地调节动力学竞争。最后，