What’s interesting is, like the other products, it was designed and marketed for one purpose but has become very popular for another. (Although in this case it could well just be a fashion, especially given how uniquely identifiable the product is.)
The main aspect of the design for popularity being low price, bought with subpar quality. It will fade soon after recent examination mentioned in sister comments to yours.
It doesn't fit into the list as a revolution (or even 'evolution') as it's just a high-density, compact and cheap battery [1] that turns out to be quite unsafe [2].
This sounds interesting. Can you elaborate?