Lithium is pretty darn awesome battery tech, honestly! It is continuously improving faster than nearly anything else in the energy industry. Solar is obviously getting cheaper faster, and wind is getting cheaper with bigger turbines, but not much else changes in energy it seems.
Chains of hydrocarbons are a better storage form for compactness, but creating that chain and deconstructing that chain are hugely inefficient processes. We've only used them up until now because the planet had saved a huge amount of its previous solar energy in that form.
There are some interesting lithium flow batteries coming out that decouple the power of the battery from the amount of storage, so that should be fairly interesting to see.
Other flow batteries will also be quite interesting for stationary uses.
We'll need lots and lots of storage for both stationary and mobile applications. For mobile applications, I can't see anything beating lithium ion without a major breakthrough. That type of breakthrough is not what those seeming breakthroughs "every 5 years" are; those are university press releases. It's rare that the real breakthrough will get the press, because the disconnect between what's happening in the field and what's actually important is enormous (this goes for most forms of science, not just energy).