Electrode

Organic chemistry

Molten salt

Fluoride

Fluorine

Engineering

Nanoarchitectures for lithium-ion batteries

Physical chemistry

Inorganic chemistry

Chemistry

Salt (chemistry)

Metallurgy

Materials science

Trifluoride

Cathode

Electrolyte

Chemical engineering

Electrochemistry

Science

Working toward fluoride batteries Owing to the low atomic weight of fluorine, rechargeable fluoride-based batteries could offer very high energy density. However, current batteries need to operate at high temperatures that are required for the molten salt electrolytes. Davis et al. push toward batteries that can operate at room temperature, through two advances. One is the development of a room-temperature liquid electrolyte based on a stable tetraalkylammonium salt–fluorinated ether combination. The second is a copper–lanthanum trifluoride core-shell cathode material that demonstrates reversible partial fluorination and defluorination reactions. Science , this issue p. 1144

Room-temperature cycling of metal fluoride electrodes: Liquid electrolytes for high-energy fluoride ion cells