Prussian blue analogues (PBAs) have been attracting intense attention owing to its two-electron storage capability and considerable cost advantage, especially in Na-ion and K-ion batteries. However, things are quite different when it comes to Li-ion batteries, because lithium-containing Li₄Fe(CN)₆ precursor is not commercially available and thus the traditionally prepared Li-deficient FeFe(CN)₆ products fail to couple with commercial graphite anode for full cells. Herein, we put forward a potential matching principle to guide the chemical pre-lithiation of FeFe(CN)₆ into a Li-rich Li_xFeFe(CN)₆ (x varies from 0 to 2) cathode. The potential matching principle was convincingly confirmed by theoretical analysis and over-lithiation experiments. Perylene-Li reagent was elaborately screened to serve as both Li⁺ and electron donor for controllable chemical lithiation reaction while preserving the host framework stable. Our work provided a general guiding principle and effective methodology for controllable synthesis of Prussian blue analogues in gradient lithiation depth, which could be served as a platform for in-depth, systematic and comprehensive research on the properties of PBAs materials.

普鲁士蓝类似物 (PBAs) 因其双电子存储能力和相当大的成本优势而备受关注，尤其是在钠离子和钾离子电池中。然而，当涉及到锂离子电池时，情况就大不相同了，因为含锂的 Li ₄ Fe(CN) ₆前驱体无法在市场上买到，因此传统制备的缺锂 FeFe(CN) ₆产品无法与商业化产品结合使用用于全电池的石墨阳极。_{在此，我们提出了一种电位匹配原理来指导 FeFe(CN) 6}化学预锂化为富锂 Li _x FeFe(CN) ₆ ( x从 0 到 2) 阴极不等。理论分析和过锂化实验令人信服地证实了电势匹配原理。Perylene-Li 试剂经过精心筛选，可作为 Li ⁺和电子供体，用于可控的化学锂化反应，同时保持主体框架稳定。我们的工作为普鲁士蓝类似物在梯度锂化深度的可控合成提供了一般指导原则和有效方法，可以作为深入、系统和全面研究 PBAs 材料性能的平台。