Rechargeable zinc metal batteries (ZMBs) are promising for fabricating low-cost, safe, and high-energy-density storage systems. However, ZMBs typically undergo interfacial side reactions and cathode dissolution during cycling, resulting in the depletion of active materials and performance decay of batteries. Here, we develop a localized high-concentration fluorinated electrolyte featuring a high fluorine/oxygen atomic ratio (388.72%) with beneficial solvation chemistry, fostering the simultaneous formation of a cathode-electrolyte interphase (CEI) enriched with C–F bonds and a ZnF2-dominant solid-electrolyte interphase (SEI). The constructed robust electrode-electrolyte interfaces (EEIs) contribute to dendrite-free zinc deposition and a highly stable cathode, demonstrating soft-packed Zn||Mn-doped V2O5 batteries with an exceptional energy density (91.25 Wh kg−1cathode+anode) and capacity retention (90.5%) over 500 cycles employing a limited zinc supply. The anode-free ZMBs deliver a record power density of 153.9 Wh kg−1cathode+anode with a high capacity retention of 80.2% over 1,500 cycles. This research provides significant insights for interface construction in multivalent ion batteries.
Recently, a solution-based method was developed to synthesize sub-nm thin one-dimensional (1D) lepidocrocite (1DL) titanium-oxide-based nanofilaments as a colloidal suspension. When converted into the solid state, these 1DL nanofilaments self-assemble into 2D layered structures. Herein, we show how a polymer—branched polyethyleneimine (bPEI)—can be used to wrap individual 1DL surfaces and arrest this 1D-to-2D structural transition. X-ray diffraction (XRD) confirmed that the polymer molecules coated onto individual 1DL surfaces. More interestingly, the bPEI-coated 1DLs form a columnar hexagonal liquid crystalline structure in the solid state, and the inter-1DL distances can be readily tuned from 1.66 to 3.00 nm by controlling the polymer-to-1DL volume ratio. Combining the XRD results and density functional theory (DFT) calculations, we conclude that the 1D nanofilaments, on average, are comprised of 2 × 2 edge-shared TiO6 octahedra roughly 0.6 nm in diameter. The tunable liquid crystalline phase could open new opportunities to realize 1DL in multiple applications.