Toyota is reportedly researching fluorine batteries that could achieve seven times the energy density of lithium-ion batteries, allowing for significantly lighter batteries or longer ranges. However, there is skepticism regarding the feasibility of these claims, especially considering that lithium has a higher reduction potential than fluorine according to standard textbooks. The discussion highlights that the stated energy density refers to the amount of stored electrical energy relative to weight, which could lead to a lighter battery design. The mechanism behind achieving such energy density is questioned, particularly since fluorine is gaseous at room temperature and the battery's operation involves shuffling fluorine between the anode and cathode rather than using it directly in redox reactions. Additionally, it is noted that energy density is influenced not only by the redox reaction but also by the mass of all components involved in the battery's operation.
