N‐Heterocyclic Molecular Additives Enable Solvation and Interfacial Chemistry Regulation for High‐Stability, High‐Rate, and High‐Capacity Lithium Metal Anodes

ABSTRACT

Most electrolyte additives enable long‐term Li plating/stripping at <3 mA cm ^{− 2} , non‐applicable to practical Li‐metal batteries (LMBs) operating at ≥5 mA cm ^{− 2} and ≥ 5 mAh cm ^{− 2} . Here, we report an interaction chemistry that enables simultaneous solvation and interfacial regulation by exploring a novel N‐heterocyclic molecule (i.e., TPTC)—comprising an N‐heterocyclic core and four pyridine units–as an efficient additive for achieving ultra‐stable Li‐metal anodes under practical conditions. Electron‐rich N atoms in TPTC serve as ion‐dipole interaction sites, inducing competitive coordination that weakens Li ⁺ solvation and enhances Li ⁺ migration in the bulk electrolyte, which homogenizes Li ⁺ concentration near the interface, favoring high‐rate Li deposition. TPTC also adsorbs on Li surface to construct a protective layer with a low interfacial de‐solvation barrier, which–together with low‐barrier Li ⁺ transport through heterocyclic cavities–facilitates uniform Li deposition. Meanwhile, electron‐deficient C–H sites in pyridine weakly interact with TFSI ⁻ , forming an anion‐rich interfacial region that in situ decomposes into an inorganic‐rich interphase, affording high‐flux Li ⁺ transport. This synergy allows stable Li plating/stripping at 10 mA cm ⁻² /10 mAh cm ⁻² for 3000 h. Paired with a high‐loading LiFePO ₄ cathode (∼15 mg cm ⁻² ) and thin Li (∼100 µm), the cell maintains 87.8% capacity after 400 cycles.