China may dominate H2 as well, but mining and refining mining materials is difficult/expensive. H2 does require membrane manufacturing (which US pioneered), but platinum group metals make the best catalysts. Innovation in other materials/approaches are progressed, but then these innovations delay electrolysis deployments as they don’t yet have the same capacity levels.
Fuel cell (Hydrogen consumption) technology is ahead of low cost mass electrolysis deployments (hydrogen production). Batteries are doing very well in China, and still finding a way to be cheaper in the west too. Batteries help produce more electrolysis from renewables.
Article is saying that batteries are important too. It is a bit misleading in saying that cobalt is needed though. Cobalt and Nickel are needed for highest performance old tech batteries. For race cars. The price revolution in batteries is most pronounced for long lasting LiFePo chemistry batteries which avoids both metals, and used in value EVs, and grid storage. Batteries are not enough alone to exterminate oil/NG use.