Core Viewpoint - Solid-state lithium metal batteries are considered the next generation of power batteries due to their high energy density and safety, but they face significant challenges in practical working conditions [2]. Group 1: Research Findings - A new study published in Nature introduces the concept of a "ductile solid electrolyte interphase" (SEI), which enhances the mechanical and lithium-ion transport properties of solid-state batteries [3]. - The research team developed a novel plastic SEI that significantly improves cycling stability under high current density and low-temperature conditions [6]. - The plastic SEI maintains structural integrity while enabling rapid ion transport, achieving over 4500 hours of long cycle life at high current density (15 mA/cm²) and high capacity (15 mAh/cm²) [6]. Group 2: Implications and Innovations - This research shifts the traditional focus on "hard" SEI designs to a new emphasis on "ductility," providing a precise construction path from solid electrolyte components to ideal interfaces [7]. - The findings offer a new strategy to address interface failure issues in solid-state batteries and provide important theoretical support for the design of new interface layers, which is crucial for the practical development of solid-state batteries [7].