| 摘要 |
The present invention relates to a lithium iron phosphate having an olivine crystal structure, and more particularly, to an olivine lithium iron phosphate which consists of secondary particles having a mean diameter (D50) of 5~100 µm where primary particles having a mean diameter (D50) of 50~550 nm are agglomerated, the primary particles and the secondary particles have compositions of chemical formula (1) Li1+a Fe1-x Mx(PO4-b) Xb (where M, X, a, x, and b are as defined in the specification), and the secondary particles have a porosity of 15~40%. The lithium iron phosphate according to the present invention has the form of secondary particles, and thus can be produced into an electrode for a lithium secondary battery having a high volume density. The lithium iron phosphate of the present invention shortens mixing time to improve process efficiency. Further, the lithium iron phosphate of the present invention has a high porosity, and therefore at least a part of secondary particles collapses and is particulated into primary particles during the compression process for manufacturing an electrode, thus preventing the degradation of ionic conductivity caused by large particle size. |
