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

Patent metadata

Field	Value
Publication number	US-9325009-B2
Application number	US-201314235633-A
Country	US
Kind code	B2
Filing date	Jun 5, 2013
Priority date	Jun 6, 2012
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

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.

First claim

The invention claimed is:

1. A cathodic active material for a nonaqueous electrolyte secondary battery represented by the following formula (1),
(Li (1−a) (M 1−x Z x ) a )(M 1−x Z x ) y P (1+b−z) Si z O 4   (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<x≦0.33; 0.9≦y≦1.0; 0<z≦0.66; 0<a≦0.1; and 0<b≦0.2.

2. The cathodic active material for a nonaqueous electrolyte secondary battery according to claim 1 ,
wherein the M is at least one transition metal element selected from Fe and Mn.

3. The cathodic active material for a nonaqueous electrolyte secondary battery according to claim 2 ,
wherein the Z is at least one metal element selected from Zr, Sn, Y, and Al.

4. The cathodic active material for a nonaqueous electrolyte secondary battery according to claim 3 ,
wherein the Z is Zr,
0.01≦x≦0.05 and 0.02≦z≦0.1.

5. The cathodic active material for a nonaqueous electrolyte secondary battery according to claim 4 ,
wherein 0<a≦0.025.

6. A cathode for a nonaqueous electrolyte secondary battery comprising:
the cathodic active material according to claim 1 ;
a conductive material; and
a binder.

7. A nonaqueous electrolyte secondary battery comprising:
a cathode that includes the cathodic active material according to claim 1 , a conductive material, and a binder;
an anode;
an electrolyte; and
a separator.

Assignees

• Sharp Kk

Inventors

• Kamimura Yuichi
• Nishijima Motoaki
• Yoshie Tomohisa
• Ohira Koji

Classifications

• H01M4/5825 Primary

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• C01B25/45

  containing plural metal, or metal and ammonium · CPC title

• Y02E60/122

  Cross-Sectional Technologies · mapped topic

• H01M4/136 Primary

  Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title

• H01M4/623

  fluorinated polymers · CPC title