Time-efficient and solvent-less free-standing solid electrolyte with an advanced fluoropolymer matrix for hybrid solid-state lithium-ion batteries

The rapid fabrication of a composite solid electrolyte based on Li 6 center dot 4 La 3 Zr 1.4 Ta 0.6 O 12 (98 wt%) is achieved under 5 min using an advanced highly fibrillating polytetrafluoroethylene (2 wt%) fluoropolymer variant. Hybrid solid-electrolyte batteries (HSSB) with LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathodes are demonstrated at 30 degrees C wherein a tenfold-reduced (5 mu L) volume of liquid electrolyte (L.E) is used to alleviate solid-solid interface contact resistances. The composite solid electrolyte maintains stable lithium plating and stripping in symmetric cells over 450 h. In CR2032 coin cells, HSSB half-cells retain 90 % of an initial 160 mAh center dot g-1-1 capacity while cells with 5 mu L L.E in conventional porous separators maintain only 6 % of an initial 132 mAh center dot g-1-1 at the 100th C/3 cycle. In full-cells, cells with 5 mu L L.E in porous separators fail to cycle from lack of sufficient ionic percolation while the HSSBs retain 90% of an initial 153 mAh center dot g-- 1 at the 100th C/3 cycle. In both half- and full-cells HSSBs, the mean coulombic efficiencies are 97.7 % and 99.6 %, respectively. This study offers a time-efficient, solvent-free, and roll-to-roll compatible means of obtaining flexible solid electrolyte films for safer batteries. .