Solid-state synthesis of lithium hexafluorophosphate, useful as a battery electrolyte, comprises reacting a lithium source with diammonium phosphate and reacting the product with ammonium fluoride

Solid-state synthesis of lithium hexafluorophosphate comprises mixing a lithium source (oxide or salt) with diammonium phosphate, heating the mixture at 150-600 [deg]C, cooling and pulverizing the product, mixing the product with a 6- to 9-fold amount of ammonium fluoride, heating the mixture at 150-400 [deg]C for 4-6 hours in a sealed PTFE vessel, and transferring the product to a dry receptacle. La présente invention propose un procédé de préparation de LiPF6 (hexafluorophosphate de lithium) où des quantités équimolaires de source de lithium pure sèche comme Li2O ou Li2CO3 ou LiNO3 sont mélangées avec des échantillons très purs et secs d'hydrogénophosphate de diammonium à l'état solide.