This does not take part in the chemical action. It is an ionic
conductor but an electronic insulator, separating the two
electrodes and providing the medium for charge transfer
inside the cell between the anode and cathode. For Lithium
ion batteries, the electrolyte is typically a non-aqueous inorganic
solvent containing a dissolved Lithium salt, e.g. LiPF6 in propylene
carbonate. Within liquid electrolyte systems, a porous separator
physically keeps the two electrodes apart to prevent a short circuit
but provide ion diffusion channels.