Patent ID: 7799457

Claim:
A method for preparing an ion storage compound, comprising steps of: providing a first reactant, said first reactant having a formula of A 3x M1 2y (PO 4 ) 3 , wherein A is at least one element selected from the group consisting of elements of Groups IA, IIA and IIIA, and M1 is at least one element selected from the group consisting of Groups IIA, IIIA, IVA and VA and transition metal elements, and 0<x≦1.2, 1.2≦y≦1.8, and said first reactant including plural micrometer-sized secondary particles, each of which has a particle size ranging from 1 μm to 50 μm and is composed of crystalline nanometer-sized primary particles, each of which has a particle size ranging from 10 to 500 nm; providing a second reactant, said second reactant being at least one compound selected from the group consisting of SiC, BN and metal oxide having a formula of M2 a O b , wherein M2 is at least one element selected from the group consisting of elements of Groups IIA, IIIA, IVA and VA and transition metal elements, and 0<a≦7, 0<b≦6; and reacting said first reactant with said second reactant to form said ion storage compound.