Tesla is a slave to the Lithium Ion process of Panasonic. If a new chemistry breakthrough comes out tomorrow (ie: Redox Flow has huge potential in the utility space, even if it has little potential in the retail space)... Panasonic will be able to switch to the new chemistry but Tesla's battery tech is basically Lithium Ion only.
Tesla's battery technology is literally the battery electronics. Not the chemical cells. Tesla seems to employ chemical experts so that their battery-electronics can better predict the effects of the chemistry... but really... they're only putting together cells. Tesla doesn't make the 18650, Panasonic does. Tesla just puts a bunch of 18650 together, as well as have some sort of algorithm to make them charge / discharge at high efficiency.
Tesla is completely dependent on Panasonic's chemistry. The speed at which LG was able to build a "Silicon-Lithium Ion" battery pack of GM's Bolt only demonstrates how "easy" the battery-pack problem is.
Or that they will sell/license batteries and technology to the top 3 car companies in the world.
I would say there are better ways to make money than a 50 percent chance to make 20 percent more.
Also these predictions are 10+ years in the future. How often have people actually predicted that far from the future? Almost none. The only ones I can think of are bets on fragility: more downsides than upsides as time progresses.