posted on 2023-12-08, 11:10authored byGiulia Galatolo, Omar Alshangiti, Camilla Di Mino, Guillaume Matthews, Albert W. Xiao, Gregory J. Rees, Maximilian Schart, Yvonne A. Chart, Lorenz F. Olbrich, Mauro Pasta
Fluoride ion batteries
(FIB) are a promising post lithium-ion technology
thanks to their high theoretical energy densities and Earth-abundant
materials. However, the flooded cells commonly used to test liquid
electrolyte FIBs severely affect the overall performance and impede
comparability across different studies, hindering FIB progress. Here,
we report a reliable Pb-PbF2 counter electrode that enables
the use of two-electrode coin cells. To test this setup, we first
introduce a liquid electrolyte that combines the advantages of a highly
concentrated electrolyte (tetramethylammonium fluoride
in methanol) while addressing its transport and high-cost shortcomings
by introducing a diluent (propionitrile). We then demonstrate the
viability of this system by reporting a BiF3–Pb-PbF2 cell with the highest capacity retention to date.