Cathodic active material for nonaqueous electrolyte secondary battery, cathode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery

摘要

A cathodic active material for a nonaqueous electrolyte secondary battery according to the invention includes a lithium-containing transition metal phosphate containing Li and a transition metal. A transition metal site and P site of the lithium-containing transition metal phosphate are replaced by elements other than elements contained in the lithium-containing transition metal phosphate, and the quantity of P site is excessive with respect to a stoichiometric proportion of the lithium-containing transition metal phosphate. With this cathodic active material, a high-power and high-capacity secondary battery which is superior in safety and cost and has superior rate performance can be provided.

主权项

1. A cathodic active material for a nonaqueous electrolyte secondary battery represented by the following formula (1),
(Li(1−a)(M1−xZx)a)(M1−xZx)yP(1+b−z)SizO4  (1)the cathodic active material comprising:
a lithium-containing transition metal phosphate whose transition metal site and P site are replaced, wherein the quantity of P site is excessive with respect to the stoichiometric proportion of the P site to the transition metal site; wherein M is at least one transition metal element; wherein Z is at least one metal element selected from trivalent and tetravalent metal elements; and wherein 0