Silicon Thermal Energy Storage has piqued my interest through my research, but aswell unsure how we fit in the picture (what Silicon product they require). I know there were a couple Australian companies building thermal energy storages, but haven't heard any news from them in quite some time, just like the article you posted is from 2018. I've never seen this article or knew MIT was into this, thanks for sharing. You made me actually go Google the latest news in the sector (Thermal storage is currently a $4.35 billion market, small potatoes in the energy world) and found this article that also sheds light on one of the Australian companies I've read about before, 1414 Degrees.

https://www.pv-magazine-australia.com/2020/07/01/whats-going-on-in-the-world-of-thermal-energy-storage/

The other Silicon Thermal Energy storage I have read about and sounded promising was TED by CCT Energy. Again, I just Google and found this from 2019 stating recent developments. 

https://newatlas.com/cct-silicon-energy-battery-thermal-energy-storage/59098/

I'm sure we fit somewhere in this market and those who require Silicon...