Umicore have been saying for a couple of years at least that...

Umicore have been saying for a couple of years at least that increasing nickel while trying to design out cobalt isn't a good idea.

"If you increase the nickel proportion, you reduce the stability of the battery and so it has an impact on cycle life, the ability to charge it fast.
Cobalt is the element that makes up for the lack of stability of nickel. There isn’t a better element than nickel to increase energy density, and there isn’t a better element than cobalt to make the stuff stable. So (while) you hear about designing out cobalt, this is not going to happen in the next three decades. It simply doesn’t work.”

https://miningnews.co.za/2018/02/13...dicated-from-electric-car-batteries-umicore/#

Their comments may have something to do with them trading in all the battery metals, but I'd certainly prefer a battery that doesn't explode...