All‐in‐One Stretchable Flexible Zinc–Air Battery Enabled by Eutectogel‐Derived Electrolyte and Electrodes

ABSTRACT Flexible zinc–air batteries (FZABs) draw attention for flexibility and high energy density, yet developing integrated ones with stable electrode/electrolyte interfaces and stretchability remains challenging. Herein, lactic acid/ethylene glycol‐polyvinyl alcohol (LA/EG‐PVA) eutectogel is rationally designed to simultaneously act as the electrolyte, zinc anode, and catalyst cathode matrix for the fabricating fully stretchable, self‐healing, all‐in‐one FZABs. The carboxyl (─COOH) and hydroxyl (─OH) groups of LA form numerous hydrogen bonds with EG and PVA, creating a dense cross‐linked structure in the eutectogel. This gives the eutectogel excellent adhesion for robust electrode/electrolyte contact and significantly enhances its liquid retention and ionic conductivity. Furthermore, the ─COOH and ─OH in LA molecules effectively immobilize water molecules via forming hydrogen bonds, which mitigates hydrogen evolution and corrosion side reactions. Simultaneously, the strong electrostatic interaction between LA and Zn(OH) 4 2− induces uniform zinc deposition, thereby suppressing dendritic growth and passivation. The all‐in‐one FZAB with eutectogel‐derived electrolyte/electrodes delivers a peak power density of 65.4 mW cm −2 , retains 44.5 mW cm −2 under 100% tensile strain, self‐heals to function under stretching after cutting, and operates from −40 to 100°C. This integrated eutectogel design approach offers a new avenue for stretchable FZABs and holds promise for more stretchable energy storage devices.