"...are promising batteries 5
"...are promising batteries 5 to 10 times cheaper in the next 5 years..."
Promises are just promises: delays, roadblocks, and downright dead-ends often occur. Until something actually hits the market it is nothing but airware: smoke and mirrors. If all company A needs to do to stop company B from beating them to market with competing technology is to say "Hey, I have a world-beater that will make yours obsolete" then very little progress will occur because there is no incentive to proceed. You should never make the Perfect the enemy of the Good. If the Good hits the market in 3-4 years and the Better hits the market 1-2 years later, by then the Good will have made further advancements to approach the efficiency or drop the cost enough that it stays competitive (or maybe it does die, but that's the way of technology). I say keep every research route going full blast and see what shakes out.