I think that as intermittent renewable energy sources get cheaper and cheaper, in addition to time-shifting of arbitrage from batteries, energy storage in chemical bonds may make sense. Methods to create synthetic fuels from electricity are in their very early days, and all of them are terribly inefficient; most go through hydrogen and that step alone results in a huge loss of energy.

So for applications where energy density is needed, e.g. jets, the fuel costs will just be that X% higher than being able to use straight electricity + battery.

I can definitely imagine a world where creating synthetic fuels from excess grid energy is cheaper than fossil fuel extraction, but it involves tons of research and development in those synthetic fuel methods, and many decades of improving renewable technologies at their current rate.