Morphology-engineered, randomly oriented graphite granules enabling PTFE-free dry anode process with enhanced lithium-ion transport

초록

Dry electrode processing is attracting growing interest as a next-generation manufacturing route for lithium-ion batteries owing to its reduced environmental footprint, lower energy consumption, and strong compatibility with thick-electrode designs. However, the realization of dry-processed anodes remains fundamentally challenging because polytetrafluoroethylene (PTFE), the key binder used in most dry-electrode systems, is electrochemically unstable at low operating potentials. Herein, we present a PTFE-free dry-anode processing strategy enabled by morphology-engineered graphite granules. Graphite granules were prepared via spray drying using an industry-standard CMC–SBR binder system, during which flake-type graphite was randomly reoriented to form isotropic secondary particles with enhanced edge-plane exposure. This particle-level morphology engineering effectively suppresses thickness-directional heterogeneity during dry electrode fabrication, leading to uniform porosity, homogeneous binder distribution, and continuous ion/electron transport pathways across the electrode thickness. As a result, dry-processed graphite anodes with high areal capacities exhibit significantly improved lithiation uniformity compared to conventional slurry-cast electrodes, particularly under thick-electrode conditions. The improved structural uniformity translates into reduced polarization, enhanced lithium-ion transport kinetics, superior rate performance, and stable long-term cycling behavior even at elevated areal capacities. This work demonstrates that particle-level morphology engineering provides a viable and scalable pathway for realizing PTFE-free dry anodes using industry-relevant binder systems, offering a practical solution for high-energy-density lithium-ion batteries requiring high-loading electrodes and fast charge–discharge capability. © 2026 Elsevier B.V.

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