No, the do worse than electric cars in that respect. The hydrogen production facilities are very expensive, so they have to run 24/7 at the same load. This is exactly what mixed badly with the varying supply of renewables. With electric cars, you just plug them in at home/at work and they charge whenever there is an oversupply of electricity. Offering special remote controlled charging outlets is going to be a game changer for the grid.

If I were to store solar in my electric car as a form of temporary storage, I get probably between 80 and 90% of what was generated by my cells delivered back to my house. All I need to do this are some slight alterations to my electrical system.

If I wanted to do this with my hydrogen car, I would need to get some expensive electrolysis station next to my house and I would get maybe 50% of stored energy back after electrolysis. I would also need to get the compressor etc maintained regularly.

Also, if you mean storage for actual driving, as in possible range, there's hardly a need for more range than a Tesla can already deliver... For most people. The biggest change to make it more feasible for pretty much all people is charging speed and that keeps improving too.

Tesla doesn't allow this because of the wear on the batteries, but it seems like a killer application for EVs and rooftop solar to be able to combine them like that.