Leveraging Synergies by Combining Polytetrafluorethylene with Polyvinylidene Fluoride for Solvent‐Free Graphite Anode Fabrication

Abstract

Solvent‐free graphite anode is fabricated successfully with the synergistic effect of polytetrafluorethylene (PTFE) and polyvinylidene fluoride (PVDF). PTFE acts as a processing aid reagent to form a self‐supporting electrode film, while PVDF acts as a functional binder when PTFE decomposes in the first lithiation process. The solvent‐free graphite electrode with high loading of 15 mg cm −2 shows good stability with more than 95% capacity retention after 50 charge/discharge cycles under the current of 0.23 mA cm −2 . Electrodes with extra high loading of 27 mg cm −2 (8.2 mAh cm −2 ) are fabricated and show good stability. Initial coulombic efficiency increases to 89% after prelithiation in the full cell with lithium iron phosphate as cathode. The capacity retention of full cells is more than 80% after 110 cycles under the current of 0.7 mA cm −2 in coin cells. The roll‐to‐roll production makes the procedure compatible with current commercial lithium‐ion batteries production lines, exhibiting great potential for upscaling production.