You must be very young, I remember when mobile phones had Ni-Cd batteries and it was very bad (you could even casually destroy your battery by charging it incorrectly!).
Li-Ion felt like a huge revolution, and the improvements it had since its introduction on the smartphone market are incredible too.
My slim and lightweight pocket supercomputer has a battery comparable to a huge power bank I had 10 years ago. If that's not revolutionary, I don't know what is.
It's about the size of a VHS cassette and holds 95Wh (Maximum for airplane travel). This thing could power a dumbphone for months and it's half the size of the ye olde luggable phones.
Li-Ion felt like a huge revolution, and the improvements it had since its introduction on the smartphone market are incredible too.
My slim and lightweight pocket supercomputer has a battery comparable to a huge power bank I had 10 years ago. If that's not revolutionary, I don't know what is.