Unless you find a way to make batteries from Hydrogen or Helium you won’t get anything lighter than Lithium.
I respectfully disagree. Hydrogen is light relative to lithium. Even if stored in a solid medium. The problem is the round trip for producing hydrogen through electrolysis, then getting power from it through a fuel cell, has a loss of at least 30% - 50%. With a battery the round trip loss of charging to discharging is 5% to 10%.
If the Dims keep doing their war on energy, I'd be interested in a hybrid BEV/HEV. With home solar you can charge your own battery (literally the only reason I have an EV is to give me some protection against the Dim's stupid war on energy). On the days I have excess solar power with nowhere useful for the power to go (home batteries and EV charged), I could run an electrolyzer to generate hydrogen for the next long trip. When driving around I could get the miles from the Battery of the BEV, but in long distances between chargers (or to bypass chargers if the Dims keep making power too expensive) I could run on hydrogen.
I wouldn’t believe anything in a Chinese patent application. Currently the world is flooded with scientific papers with Chinese authors that have faulty, biased, or even no research supporting them. The system of power review has been gamed.
The other thing is who thinks using sodium in batteries is a great idea. Lithium batteries burn, sodium reacts with water by exploding, violently.