Naughty naughty "Jim", you can carry on trying to trash hydrogen, to carry on selling the false information that somehow lithium batteries are the nirvana for the future of energy storage in all applications, even for the propulsion of large scale passenger flights, which is ridiculous.

For the benefit of third parties:

https://eric-bott.medium.com/yes-we-will-be-flying-in-hydrogen-powered-passenger-planes-93779606fff7

The reference Jim is referring to, from that conversation is this one:

https://www.doitpoms.ac.uk/tlplib/batteries/batteries_lithium.php

Notice it does not have the words quoted by Jim anywhere (Do a search on "Maximum", to find all occurrences).

What it does say is this statement, which should be the thing Jim saw, which convinced him too, of the real limitations of lithium batteries, if he was sincere, is this:

"The only practical method for increasing the specific energy density of a Li-ion cell is to decrease the weight of the auxiliary components of the cell. It is widely believed that with a considerable amount of research and development the maximum specific energy density that can be achieved for a Li-ion cell within the next five years will reach 220 Wh/kg of the cell."

ie 0.22kWhrs per kg.

I have an e-bike with a battery that has just over 1KWhr for 7.5 Kg weight. This is, amongst e-bikes not bad energy to weight density relatively speaking, and it fits with where the development of Lithium actually is.

Even owning a humble e-bike would be an education for you, "Jim".