The Li/Fe disordering confined within the single unit cells of LiFePO₄ (LFP) crystals has been notoriously plaguing their reversible Li⁺ storage, capacity, and thus service life, posing a grand challenge to sustainable battery technologies. Yet, the atomistic mechanisms of such disordering are scarcely explored, not to mention efficient strategies to reorder the antisite Li/Fe and rejuvenate LFP. Intuitively, the reordering of antisite Li/Fe should occur via Li–Fe inter-atomic “leap” within the Å-scale unit cell, given the kinetic energy barrier being overcome by a transient stimulus. We herein report the high-temperature shock (HTS) technique to trigger such atomic-scale “leaping” movement of antisite Li–Fe pairs: with the high-temperature field being transiently exerted through each bulk LFP crystal, the Li–Fe inter-atomic reordering occurs swiftly and coherently from unit cell to unit cell in milliseconds, far outpacing the onset of potential detrimental side reactions (such as impurity diffusion and LFP phase deterioration). Combining in-depth atom-resolved microscopic imaging, theoretical calculation, and property evaluation, three types of Li/Fe disordering were identified and efficiently repaired on the order of seconds, along with superior electrochemical performances. This work not only discloses the disordering and reordering fundamentals of the LFP system but also proposes an efficient and sustainable strategy to regenerate aged and degraded LFP with advanced performance and significant techno-economic benefits.

中文翻译：

---

反位Li/Fe缺陷的原子观察和瞬态重排以实现可持续的LiFePO4


LiFePO ₄ (LFP) 晶体的单个单元电池内的 Li/Fe 无序性一直困扰着其可逆 Li ⁺存储、容量和使用寿命，对可持续电池技术构成了巨大挑战。然而，这种无序的原子机制很少被探索，更不用说重新排序反位 Li/Fe 和恢复 LFP 的有效策略了。直观上，考虑到动能势垒被瞬态刺激克服，反位Li/Fe的重新排序应该通过Å级晶胞内的Li-Fe原子间“跳跃”发生。我们在此报告了高温冲击（HTS）技术，以触发反位Li-Fe对的这种原子级“跳跃”运动：通过每个块状LFP晶体瞬时施加高温场，Li-Fe间原子重新排序在几毫秒内从一个晶胞迅速连贯地发生，远远超过了潜在有害副反应（例如杂质扩散和 LFP 相恶化）的发生速度。结合深入的原子分辨显微成像、理论计算和性能评估，识别出三种类型的Li/Fe无序结构，并在数秒内有效修复，并具有优异的电化学性能。这项工作不仅揭示了LFP系统的无序和重新排序的基本原理，而且提出了一种有效且可持续的策略来再生老化和退化的LFP，具有先进的性能和显着的技术经济效益。