Doping have been considered as a prominent strategy to stabilize crystal structure of battery materials during the insertion and removal of alkali ions. The instructive knowledge and experience acquired from doping strategies predominate in cathode materials, but doping principle in anodes remains unclear. Here, we demonstrate that trace element doping enables stable conversion-reaction and ensures structural integrity for potassium ion battery (PIB) anodes. With a synergistic combination of X-ray tomography, structural probes, and charge reconfiguration, we encode the physical origins and structural evolution of electro-chemo-mechanical degradation in PIB anodes. By the multiple ion transport pathways created by the orderly hierarchical pores from “surface to bulk” and the homogeneous charge distribution governed in doped nanodomains, the anisotropic expansion can be significantly relieved with trace isoelectronic element doping into the host lattice, maintaining particle mechanical integrity. Our work presents a close relationship between doping chemistry and mechanical reliability, projecting a new pathway to reengineering electrode materials for next-generation energy storage.

掺杂已被认为是在插入和去除碱离子过程中稳定电池材料晶体结构的重要策略。从掺杂策略获得的指导性知识和经验在阴极材料中占主导地位，但在阳极中的掺杂原理仍不清楚。在这里，我们证明了痕量元素掺杂能够实现稳定的转化反应，并确保钾离子电池（PIB）阳极的结构完整性。通过X射线断层扫描，结构探针和电荷重新配置的协同组合，我们可以编码PIB阳极中电化学降解的物理起源和结构演变。通过从“表面到主体”的有序分层孔隙以及在掺杂的纳米域中支配的均匀电荷分布，产生了多种离子传输途径，通过将痕量等电子元素掺杂到主体晶格中，可以显着缓解各向异性膨胀，从而保持粒子的机械完整性。我们的工作提出了掺杂化学与机械可靠性之间的密切关系，为重新设计用于下一代能量存储的电极材料开辟了一条新途径。