Multivalent Dipole Interactions‐Driven Supramolecular Polymer Layer Enables Highly Stable Zn Anode Under Harsh Conditions

Abstract Aggressive side reactions and dendrite growth, associated with the unstable Zn anode/electrolyte interface, have impeded the practical application of Zn metal‐based batteries. Here, a donor‐acceptor (D‐A) polymer is employed to reconstruct a robust supramolecular polymer (SP) protective layer to achieve highly stable Zn anodes. The D‐A polymer possessing abundant electron donor and acceptor sites can dynamically co‐crosslink with water molecules and Zn 2 ⁺ through multivalent dipole interactions (MDIs), resulting in the formation of a supramolecular polymer network. The MDIs disrupt the original strong hydrogen‐bonding network within the D‐A polymer, leading to the reconfiguration of polymer chain conformations and an increase in the intermolecular free volume exposing more widely distributed dipoles, thereby regulating the Zn 2+ desolvation behavior and facilitating rapid and uniform Zn 2+ plating. Meanwhile, the resultant supramolecular network endows the SP with an ultra‐high mechanical modulus of 10.4 GPa, which can homogenize the stress distribution during the plating process for effective dendrite suppression. Consequently, the SP‐assisted asymmetric cell achieves nearly 99.94% Coulombic efficiency over 9000 cycles, enabling the Zn/Zn cell to cycle for over 540 h under an ultrahigh 92% Zn utilization. Outstanding cycling stability is also successfully demonstrated in high mass‐loading (≈12.8 mg cm −2 ) pouch cells, further demonstrating its prospects for practical applications.