A method for producing ferric phosphate hydrate particles, a method for producing olivine-type lithium iron phosphate particles, and a method for producing a nonaqueous electrolyte secondary battery.

摘要

The present invention relates to ferric phosphate hydrate particles for use as a precursor of olivine type lithium iron phosphate particles, wherein the ferric phosphate hydrate particles exhibit at least one crystal structure selected from the group consisting of a strengite crystal structure and a meta-strengite (phosphosiderite) crystal structure, and have a sodium (Na) content of not more than 100 ppm and a molar ratio of phosphorus to iron (phosphorus/iron) of not less than 0.9 and not more than 1.1. The ferric phosphate hydrate particles according to the present invention are suitable as a precursor of olivine type lithium iron phosphate particles for a positive electrode substance of non-aqueous electrolyte secondary batteries, and are in the form of fine particles and have a very small content of impurities.