I understand that, but the sheer number of them increases the likelihood of it coming to fruition.
http://news.stanford.edu/news/2015/march/aluminum-ion-battery-033115.html
One of the new alternatives, just out of the Stanford labs, cheap, fast charging, and has many times more recharging cycles than lithium ion, and does not catch fire. Fools looking for market that is leaving, as usual.
Tesla will use ANY battery with the right specs.
DK