HC, I agree with everything in your post (Re:  WTH?), except for that last bit:

"On the other hand, Lithium for power storage will increase demand if the price becomes low and EV production cannot absorb the supply"

JMO, but I don't see lithium ion batteries as the major presence in static non mobile power storage locations in the future. 

ESS, Energy Storage Systems, can roughly be divided into BESS and non BESS (Battery Energy Storage Systems and all other types of Energy Storage Systems).  So, any discussion of "power storage" should specify whether or not the discussion is expanded to all forms and kinds of ESS or whether it is limited to BESS vs Non Battery ESS in order to compare appropriately technologies that will compete in the same market niche, now and in the forseeable future. Even dividing the topic further it is beneficial to distinguish between portable and non portable BESS, the later to include large scale grid level energy storage systems for utilities.

Lithium Ion Batteries have a competitive advantage at present in fixed base ESS, but that advantage is not set in concrete and should evaporate over time barring any order of magnitude level new expansion of the capability of lithium ion technology that may not even be conceived of at this present point in time.

As far at the BESS portion of ESS goes then at the present time it would appear that Lithium Ion based BESS get the most attention and are predominant, but that is changing and as time moves forward less and less of the per cent of BESS  systems that are large scale grid level systems will belong to Lithium Ion batteries because of the advantages that non mobile (fixed) and non Lithium Ion based  developing technologies, such as vanadium flow batteries, have.

These advantages dissipate when you are talking about portable BESS scenarios, but for fixed base, non mobile, ESS the future most likely belongs to flow batteries and possibly other technologies.

Some links on the subject are below:

Battery Energy Storage Systems (BESS) | What It Is & How It Works (carboncollective.co)

Fact Sheet | Energy Storage (2019) | White Papers | EESI

Why Vanadium Flow Batteries May Be The Future Of Utility-Scale Energy Storage (forbes.com)

Flow batteries for grid-scale energy storage | MIT Energy Initiative

One company that makes commercial grade Vanadium Flow Batteries touts the advantages of their particular brand in the following internet homepage:

Vanadium Flow Battery Energy Storage - Invinity

Cheaper, Safer and More Recyclable?   So says a claim in the article linked below:

Vanadium redox flow batteries can provide cheap, large-scale grid energy storage. Here's how they work - ABC News

Bottom line:  as for the future market in fixed base ESS ( non portable and non mobile ) grid level utility grade systems, I think the writing is on the wall clearly that the market share for Lithium Ion batteries in this particular market niche will decline as these other technologies emerge and improve, however the world need for portable lithium ion battery applications goes way beyond the single area of electric vehicles and until some unknown date in the futre, probably not the near future, Lithium Ion batteries will rule supreme in most, if not all, portable and mobile ESS situations.  Thank goodness for that!

 These portable and mobile situations whereby Lithium Ion will itself "rule supreme" account for an ever expanding number of locations that should continue to expand the demand for lithium carbonate and lithium hydroxide for many years, if not many decades, into the future.

JMO

Okiedo