Structural Engineering of PTFE–Carbon Conductive Binder Domains for High-Loading Dry Electrodes for Lithium-Ion Batteries

High-loading dry electrodes are a promising strategy for increasing the energy density of lithium-ion batteries by eliminating solvent-based processing and reducing inactive components. However, during dry mixing, PTFE can locally agglomerate or excessively cover the surface of active material particles, blocking electrochemically accessible sites and disrupting electron- and Li-ion-transport pathways. In this study, we developed a structural design strategy in which carbon conductive additives are pre-composited with PTFE prior to shear-induced fibrillation. The resulting PTFE–carbon composite domains form conductive clusters that facilitate the development of a percolated electron-conduction network while promoting more uniform PTFE fibrillation. This pre-composite structure also suppresses PTFE re-agglomeration and limits excessive binder coverage on NCM particle surfaces, thereby preserving active reaction sites for Li-ion insertion and electron transfer. Rather than altering the intrinsic properties of the electrode components, this approach controls their spatial organization to construct an efficient conductive binder domain, providing a practical route to overcoming the transport and structural limitations of high-loading dry electrodes for lithium-ion batteries.