I've also pondered whether Cobalt & Li's fates are tied however have a different view: Lithium demand will indeed increase but the majority / all of the demand can be met with either existing mines or new mines targeting brines in the US and South America.
Compare that to Cobalt where Co is generally a by product with a substantial amount of producing mines shutting operations. There is a realistic supply deficit looming with cobalt (albeit not as massive as some predict), add to that it's use in the energy space and the fundamentals are a little more solid than lithium.
Lithium also has a much sexier name than cobalt, and has the primary name in lithium ion batteries - hence it leads the bubble.
IMO
BAR Price at posting:
6.2¢ Sentiment: Buy Disclosure: Held