Warning; what follows are the ramblings of a non-engineer, though someone with enough knowledge to be dangerous but not enough self awareness to grasp this. Also partial to yoga.
What are the rate-limiting factors for this ? Simplicity, safety, and efficiency.
Simplicity; got some nice promo film which shows some shiny machines in the lab, with some a very plausible patter on using semiconductor foundry approaches to store hydrogen, and release it with light.
Safety; it's not as tricky as having a high pressure and flammable gas, that tends to leak out as it's such a wee molecule.
Efficiency; this is where i'm wondering. Putting it on the film must take some energy, as well as getting it off again - but they don't seem to describe this clearly in the youtube clip. Seems to be a bit of an omission ? If there's an inherently high energy cost of the storage system, it'll be a limitation if rolled out at global scale (though that didn't stop the inefficient ICE succeeding...but efficiency is where the current competition is at)
So, energy density...
From their website;
This is good for comparison versus other forms of Hydrogen storage, but it doesn't tell me how it stacks up versus a Li ion battery. Luckily, someone on this forum might know the answer, and perhaps compare with fossil fule.
I don't get how their figures in the youtube clip relate to the numbers above ? Energy density of 8.7kWh/kg seems a bit low but adequate ? At 4 miles per kWh that'd be around 32 miles. A kilo of petrol (roughly a litre ? should've listened in chemistry class...) gets you 20-50 miles (?).
IMO, hydrogen has a lot of potential particularly as it might be easier to ship it from distant wind or solar generation than it's currently possible to move electricity. Whether it's wise or feasible to put it in a car is another matter.