> Also, people in that industry know that surely no one would proudly advertise a "100 hour battery" if it weren't significantly cheaper than lithium ion on a per kWh basis, so the term "100 hour battery" also means (to the right audience) that the batteries have to be cheaper than lithium ion.

That seems like a stretch or an unwise convention. It could have some other advantage instead. Loudly proclaiming a disadvantage doesn't tell you what's good about a product, or what circumstances it's useful in.