I don't know why you are saying that. Batteries are expensive. To recoup the capital expense you need to charge and discharge them daily (so you can buy the electricity cheap and sell it expensive and you get a profit). If you want to use them for long term storage, then you buy cheap electricity in the summer, sell it for a profit in the winter, do the same each year, and find out in a few years that you are broke.
With hydrogen, the storage is cheap. We already store natural gas in tanks. We can switch to hydrogen. Maybe hydrogen will leak more, but 1. hydrogen is not a greenhouse gas and 2. the square-cube law tells you that for large tanks you don't really care about leakage.
I don't think we will find an alternative to hydrogen for long term storage of electricity.
You seem to happily ignore the distribution costs, metal embrittlement, sheer loss of efficiency and rest of factors that make hydrogen a bad idea for almost any use where it's not yet being used.
You can't ship things in steel vessels overseas because steel rusts in contact with water, especially salty water. See what I did there?
> distribution costs
What about distribution costs? Hydrogen can replace natural gas. Wherever you have a gas burning powerplant, you can retrofit it to burn hydrogen. The tanks that store gas for that plant can be modified to hold hydrogen. Whatever distribution costs are incurred for natgas will be incurred by hydrogen. Some will go up, some down, but not by orders of magnitude.
> sheer loss of efficiency
As opposed to what? In a world powered by solar and wind, you'll have times (lots of times) when you generate more than you consume. The least efficient option is to just not generate. Generating electricity and converting it to hydrogen, and then the hydrogen back to electricity at a later time may or may not be economically profitable. In the cases where the economics will work out, people will do that, where it won't people won't do it. But the economics will always be against batteries for long term storage, except if by some miracle batteries will get to be 100 times cheaper (not a mistake, 100).
Other chemical storage solutions (ammonia, methanol, ethanol, lithium hydride) need one extra step that will be very expensive. There are slight chances for one of those to make sense, but my bet is that they won't. Why? Because both Europe and Japan are betting very, very big bucks on hydrogen.
So what is your better option? What alternative technology has the potential to be used to store six months worth of energy for an entire continent?
Nobody is saying that hydrogen technology is without its problems, but it is feasibly scalable unlike anything else I am aware of, and it is not some kind of mythical vapourware that exists only in the form of CAD renderings.
> Steel with an ultimate tensile strength of less than 1000 MPa (~145,000 psi) or hardness of less than HRC 32 on the Hardness Rockwell Scale is not generally considered susceptible to hydrogen embrittlement.
Cube square law also makes small scale hydrogen storage more expensive than batteries.
Then you're back to limited niche uses, or needing expensive, leaky distribution.
The best use of hydrogen for seasonal arbitrage is making it into sponge iron and ammonia for steel and fertiliser then storing that. Then your seasonal-cadence variability is gone.
With hydrogen, the storage is cheap. We already store natural gas in tanks. We can switch to hydrogen. Maybe hydrogen will leak more, but 1. hydrogen is not a greenhouse gas and 2. the square-cube law tells you that for large tanks you don't really care about leakage.
I don't think we will find an alternative to hydrogen for long term storage of electricity.