Bismuth key to Ambri's gird-scale liquid metal battery Ambri's grid-scale liquid metal battery, developed by MIT and funded by Bill gates and Total will use bismuth in the positive electrode. Ambri is looking to be in commercial production of these large grid-scale batteries in 2018/19. Looks like Bismoth allows lead the other componet of the positive electrode a higher voltage while maintaining its lower melting point. Interesting to note that Fortune Minerals has one of the largest Bismuth deposits in the world. I've provided some links below. Na/NaOH-Nal/Pb-Bi looks like the battery make-up with Pb-Bi the common theme in LMB for low temp opperation.
https://www.bnn.ca/related/tag?Tag=Ambri
https://jes.ecsdl.org/content/162/14/A2729.shorthttps://
news.mit.edu/2016/battery-molten-metals-0112
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