> but they're all LiPo/Li-Ion batteries, what's the difference?

As I mentioned, the article specifically mentions that the battery chemistry has been changed and improved.

It neglects to dive into the chemical engineering specifics of such changes, as would be expected for press such as the WSJ.

I dare say there is as much variation in the attributes of the LiPo/Li-Ion battery family as there is within the borosilicate glass or soda–lime glass families (ie heaps).