Dry electrodes are rigorously developed for sustainable and efficient battery manufacturing. Currently, polytetrafluoroethylene (PTFE) binders dominate dry processes, yet their production contributes to significant CO2 emissions, and concerns persist regarding their high fluorine content, especially in light of evolving Per- and Polyfluorinated Substances (PFAS) restrictions. Moreover, the poor adhesion of bare current collectors necessitates a wet coating-based primer layer. In this study, we introduce an alternative dry processing concept based on a thermoplastic fluorine-free binder with low environmental impact and high productivity. Paraffin, a short-chain family of saturated hydrocarbons known as an n-alkane, is the most stable chemical species owing to its C-H covalent bonds and the wide gap between HOMO-LUMO energies. It also has a low melting temperature, allowing facile cohesion of the active materials to be interconnected by mild pressing activation. This new dry electrode binder provides substantial electrochemical properties based on both NCM cathodes and graphite anodes over 7 mAh cm−2. Furthermore, it implements true solvent-free adhesion without the wet-coating of primers on the current collector. This unique characteristic of paraffin enables a powder-to-electrode manufacturing strategy with pattern coating, which alters the well-known PTFE-based freestanding concept. This integrated approach bridges the gap between materials and processes, paving the way for sustainable advancements in battery electrode technology.
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