Rhombohedral nasicon compound and battery

Abstract

Disclosed is a nasicon compound and a method of making it. The nasicon compound is rhombohedral at room temperature and has the general formula M.sub.1+x+O.02y+0.04z M'.sub.2-0.02(y+z) M".sub.0.02y M"'.sub.0.02z M"".sub.x M""'.sub.3-x O.sub.12 where M is selected from lithium, sodium, calcium, and silver, M' is selected from zirconium, titanium or hafnium, M" is selected from yttrium, scandium or lanthanum, M"' is selected from magnesium, calcium, strontium or barium, M"" is selected from silicon and germanium, M""' is selected from phosphorous and arsenic, x is about 1.6 to about 2.2, y is about 0 to about 15, and z is about 0 to about 15. The preferred compound is Na.sub.1+x Zr.sub.2 Si.sub.x P.sub.3-x O.sub.12. A sodium sulfur battery using the nasicon compound is also disclosed.

Dependencies are inferred from the claim text.