Lithium sucks, indeed, since the Chinese have most of it and hold the rest of the world at ransom. But sodium, really ? that thing is a bastard, just ask the nuclear industry (hello, Superphoenix, Monju and Clinch River). Corrosive, flammable, reactive, explosive... what's not to like ?
No need for fuel cells, folks. What we need is
ammonia IC cars. Ammonia has zero carbon, the fertilizer network already in place, and, most importantly, any plain old IC engine can be modified from gasoline to ammonia pretty easily. All of this also applies to methanol, minus the carbon-free aspect.
Even if it has half the energy of gasoline, an ammonia car range would remain far, far better than any electric car. Or the technology used to make ultra light and ultra efficient electric cars... could be used for an ammonia IC car, beating lithium batteries into a pulp.
Unfortunately, ammonia for cars is like hydrogen peroxide for rockets: its (supposed) safety issues are completely overblown (toxicity, my ass: isn't gasoline dangerous if you smoke a cigarette, breath the exhaust, or try to drink it ? common...)
Heck in the 60's they made studies of ammonia and methanol fuel aircrafts and helicopters. The US Army had a grandiose project: portable, mobile nuclear reactors to split nitrogen from air and hydrogen from water and recombine that into ammonia to replace gasoline. And then... screw you, Saudi Arabia.
The usual jet or turbine could be converted to ammonia but the aircraft performance would take a big hit. Still far more realistic than any E-VTOL or electric aircraft.
As for hydrogen cars, being a space nerd since the craddle, I can tell you, they are a folly. Handling of liquid hydrogen is a complete and giant PITA, something that really can't be folded into your daily gas station. Unless you turn it into a miniature Cape Kennedy Launch complex, as far as drastic safety rules go. Plus the silly thing has 2.5 times the tank volume of gasoline, methanol or ammonia.
