Core Viewpoint - The commercialization of solid-state batteries is beginning to take shape with the emergence of GWh-level orders, but the current delivery relies on the modification and innovation of traditional lithium-ion battery wet coating equipment rather than a revolutionary new production model [2][3]. Group 1: Challenges in Manufacturing - The transition from liquid electrolyte to solid electrolyte in batteries is a fundamental step towards solid-state technology, which involves significant changes in the physical properties of the slurry system [4][6]. - The ideal battery slurry must exhibit "shear-thinning" rheological properties, allowing for low viscosity during pumping while maintaining structural integrity during drying [5]. - The introduction of solid electrolytes transforms the slurry into a "rich solid phase," leading to increased viscosity and the formation of hard agglomerates that can cause defects in the coating process [6][7]. - The complexity of the slurry system increases as it evolves from a simple "bimodal particle" system to a "multimodal particle" blend, complicating the mixing of different solid particles with distinct physical and chemical properties [8]. Group 2: Material and Process Divergence - Different solid electrolyte chemical systems present unique challenges for wet coating processes, particularly with oxide-based electrolytes that are hard and brittle, leading to wear on equipment [10][12]. - Companies like QuantumScape focus on achieving fundamental breakthroughs in material performance, which may conflict with modern battery manufacturing's efficiency goals [12]. - In contrast, companies like Penghui Energy prioritize process compatibility and commercial efficiency, aiming for high energy density while maintaining cost parity with traditional lithium batteries [14][15]. Group 3: Sulfide Route Challenges - The sulfide route faces a series of interconnected technical constraints, with wet coating emerging as the mainstream method for producing sulfide solid electrolyte membranes [17][18]. - The chemical instability of sulfide materials poses challenges in solvent selection and binder compatibility, leading to difficulties in achieving both solubility and adhesion [19][20]. - The industry is exploring various coating methods, with high-precision slot die coating seen as essential for large-scale safe production [22]. Group 4: Equipment and Industry Response - The manufacturing challenges in battery technology are creating commercial opportunities for upstream equipment manufacturers, who are actively deploying solutions to meet customer demands [23]. - Companies like Mannesmann have introduced high-temperature coating systems to address issues related to high solid content slurries [24]. - Other leading equipment manufacturers are also developing parallel dry and wet solid coating systems to enhance production capabilities [26][27]. Group 5: Integration of Materials and Processes - The successful commercialization of solid-state batteries requires a deep integration of materials, processes, and final product forms, leading to new manufacturing challenges [30][31]. - The current wet coating methods struggle to balance high ionic conductivity and flexibility in electrolyte membranes, highlighting the need for suitable binder selection [31]. Conclusion - The path to solid-state battery commercialization is not linear but involves navigating multiple contradictions and constraints while seeking localized optimal solutions [32]. - Future success in solid-state battery manufacturing will depend on the ability to integrate cross-disciplinary knowledge effectively [33].