PRODUCTION OF LITHIUM NITRIDE

摘要

PROBLEM TO BE SOLVED: To obtain lithium ion-conductive high-purity lithium nitride having high utility value as a solid electrolyte by allowing metal lithium contg. a small amt. of sodium to react with nitrogen and removing the residual sodium by heating. SOLUTION: Metal lithium contg. >=0.01% sodium is allowed to react with nitrogen and the resultant lithium nitride is heated to >=450 deg.C in a nitrogen atmosphere to remove the residual sodium. In order to shorten time, the lithium nitride may be heated to about >=550 deg.C. The upper limit of heating temp. is preferably <=700 deg.C because the m.p. of lithium nitride is 840-845 deg.C and lithium nitride is liable to sinter at >=700 deg.C. Since lithium nitride is solid, the residual sodium is easily separated and the loss of lithium nitride and the corrosion of a vessel are slight.