AI 中文总结
研究全固态钠电池循环中枝晶生长问题，应用基于密度泛函理论计算的相场模型，揭示枝晶剥离不对称导致孤立钠金属形成并加速枝晶穿透，还研究了相关影响因素，为稳定阳极/电解质界面提供设计原则。
AI 中文摘要
循环过程中的枝晶生长仍然是全固态电池（SSB）面临的关键挑战，限制了其固有安全性和高能量密度的全面实现。特别是，充放电循环中连续枝晶穿透的机制仍知之甚少，且难以通过实验表征。本研究应用基于密度泛函理论计算的相场模型，以合理化和可视化纯钠或钠-锑合金阳极以及多晶Na₃SbS₄电解质的钠（Na）SSB循环过程中的枝晶穿透行为。我们表明，由于晶界几何形状，枝晶剥离在本质上相对于镀覆是不对称的，导致在循环之间形成孤立的钠金属。这种残留的钠金属在晶界结处动力学稳定，并在随后的镀覆过程中容易重新激活，从而加速和放大枝晶穿透。我们进一步研究了施加电压、固体电解质微观结构和阳极化学对这一现象的影响。这些发现确定了孤立的钠金属是钠SSB中枝晶持续生长的关键因素，并为稳定钠SSB中的阳极/电解质界面提供了设计原则。
英文摘要
Dendrite growth during cycling remains a critical challenge for all-solid-state batteries (SSBs), limiting the full realization of their inherent safety and high energy density. In particular, the mechanisms of continuous dendrite penetration during charge-discharge cycling remain poorly understood and are difficult to characterize experimentally. This study applies a phase-field model, informed by density functional theory calculations, to rationalize and visualize the dendrite penetration behaviors during cycling in sodium (Na) SSBs with pure Na or Na-Sb alloy anodes and polycrystalline Na$_3$SbS$_4$ electrolyte. We show that dendrite stripping is intrinsically asymmetric with respect to plating due to grain boundary geometry, leading to the formation of isolated Na metal that persists between cycles. This residual Na metal becomes kinetically stabilized at grain-boundary junctions and is readily reactivated during subsequent plating, thereby accelerating and amplifying dendrite penetration. We further investigate the effects of applied voltage, solid-electrolyte microstructure, and anode chemistry on this phenomenon. These findings establish isolated Na metal as a key contributor for continued dendrite propagation in Na SSBs and provide design principles for stabilizing anode/electrolyte interfaces in Na SSBs.
