Prelithiation for Lithium‐Ion Batteries: Material and Process Innovations

Prelithiation has emerged as a pivotal strategy to address irreversible lithium loss in lithium-ion batteries (LIBs) and to unlock higher energy density electrode chemistries. This review delineates the fundamental driving forces behind prelithiation, from escalating market demands for energy density to intrinsic electrode limitations and the mechanistic origins of lithium inventory depletion. Beyond compensating initial losses, prelithiation is framed as an active tool for reshaping lithium inventory evolution and interfacial stability throughout battery operation. A quantitative framework is introduced to evaluate the projected benefits of prelithiation on energy density, cycle life, and cost at the cell and system levels, establishing a direct link between lithium inventory engineering and techno-economic performance. The major technological pathways are critically assessed, with emphasis on contact prelithiation using lithium metal and electrochemical or chemical approaches based on lithium-rich additives. Representative case studies are discussed to elucidate mechanistic distinctions, advantages, and trade-offs across strategies, evaluated through the lenses of intrinsic material properties, safety considerations, and scalability. Finally, the review outlines key challenges for industrial implementation and highlights emerging research directions, including intelligent lithium reservoir design and integration with next-generation battery architectures, positioning prelithiation as a foundational design variable for advanced energy storage systems.