A New Metalgel Current Collector for Simultaneous Rapid and Stable Zinc Electrochemistry

Achieving both high-rate capability and long-term cycling stability in zinc anode remains challenging due to the fundamental trade-off. Fast kinetics require maximum interfacial area for charge transfer, while stability demands minimal zinc/electrolyte contact to suppress parasitic reactions and dendrite growth. However, in previous studies, zinc deposited at the electrode/electrolyte interface, leading to limited lifetimes (≤ 1200 h at a utilization ratio of ≥ 60%) and high overpotentials (≥ 480 mV at 50 mA·cm^-2). Here, we design a new metalgel current collector to effectively resolve the above limitation. The metalgel comprises a biphasic gallium-indium-zinc continuum immobilized within a 3D polymer network, establishing both ion and electron conduction pathways that maximize the electrochemically active interface. The biphasic gallium-indium-zinc contains solid metallic zinc dispersed within the liquid gallium-indium-zinc alloy phase, enabling inward zinc deposition/stripping via a reversible dissolution-precipitation alloying process. This inward-deposition/stripping minimizes zinc/electrolyte contact and suppresses parasitic reactions and dendrite formation, enabling zinc anodes to achieve over 4300 h of stable cycling at 80% zinc utilization ratio and maintain only 156.6 mV overpotential at an ultrahigh current density of 100 mA·cm^-2. By decoupling interfacial kinetics from interfacial instabilities, this work presents a new paradigm for high-performance metal batteries.