发表机构
Technical University of Denmark; German Aerospace Center (DLR); Helmholtz Institute Ulm (HIU); Ulm University（丹麦技术大学; 德国航空航天中心; 乌尔姆亥姆霍兹研究所; 乌尔姆大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用相场法模拟开路条件下SEI从致密相到多孔相的演变，发现转变时间随SoC增加而延长，并受SoC-OCV关系控制，为电池储存稳定性提供关键见解。
AI 中文摘要
固体电解质界面（SEI）对于电池的长期稳定性至关重要，因为它影响电极与电解质之间的反应。尽管已有研究，但SEI从致密相演变为多孔相的过程仍未完全理解。在此，我们利用相场框架在开路条件下研究了SEI随荷电状态（SoC）的演变。引入空间相关噪声来描述随机输运扰动，并根据界面粗糙度的演变评估致密相到多孔相的转变时间，该粗糙度源于噪声诱导输运与表面弛豫之间的竞争。模拟揭示了三种不同的粗糙度演变机制。预测的转变时间通常从20% SoC时的大约一个月增加到80% SoC时的超过七个月，在55%至60%之间变化显著。这一变化对应于石墨的SoC-OCV关系，该关系通过能斯特条件控制界面Li0自由基浓度。在由不可逆容量损失引起的动态SoC条件下，随着储存期间SoC的演变，转变行为发生变化。这些结果表明，SoC-OCV关系是决定开路储存下SEI相稳定性和致密相到多孔相转变时间的核心因素。
英文摘要
The solid electrolyte interphase (SEI) is essential for the long-term stability of batteries because it influences the reactions between the electrode and electrolyte. Despite previous studies, the SEI evolution from dense to porous phases remains incompletely understood. Here, we investigate the SoC-dependent evolution of the SEI using a phase-field framework under open-circuit conditions. Spatially correlated noise is introduced to describe stochastic transport perturbations, and the dense-to-porous transition time is evaluated from the evolution of interface roughness arising from the competition between noise-induced transport and surface relaxation. The simulations reveal three distinct roughness evolution regimes. The predicted transition time generally increases from approximately one month at 20% SoC to more than seven months at 80% SoC, with a pronounced change between 55% and 60%. This change corresponds to the graphite SoC-OCV relation, which controls the interfacial Li0 radical concentration through the Nernst condition. Under dynamic SoC conditions caused by irreversible capacity loss, the transition behavior changes as the SoC evolves during storage. These results show that the SoC-OCV relation is central to determining SEI phase stability and the dense-to-porous transition time under open-circuit storage.
CommentsIt has 7 figures and 1 supplementary paper
