IP Library Granted Patent US 7,972,729
Granted Patent B2
US 7,972,729 · App. 12/170,177 · Granted Jul 5, 2011

Positive electrode material for non-aqueous electrolyte secondary battery, non-aqueous electrolyte secondary battery using the same, and method for producing positive electrode material for non-aqueous electrolyte secondary battery

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,972,729
App. No.
12/170,177
Granted
Jul 5, 2011
Kind
B2
Abstract

The invention includes, as a positive electrode material, active material particles comprising a lithium-containing manganese oxide represented by the general formula: Li 1+a Mn 2−x−a M x O 4+y where M is a transition metal element other than Mn, 0<x≦0.5, −0.2≦y≦0.5, and 0≦a≦0.33. The molar ratio A of M to the total of Mn and M in the surface of the active material particles and the molar ratio B of M to the total of Mn and M in the whole active material particles satisfy the relations: A/B>1.0 and A≧0.3. In an X-ray diffraction analysis using CuKa radiation as an X-ray source, the intensity ratio of the largest peak of peaks attributed to an oxide of the transition metal element M to a peak around 2θ=36.4° is 0.25 or less.

Claims (7)

1. A positive electrode material for a non-aqueous electrolyte secondary battery, comprising active material particles that comprise a lithium-containing manganese oxide represented by the general formula: Li 1+a Mn 2−x−a M x O 4+y where M is a transition metal element other than Mn, 0<x≦0.5, −0.2≦y≦0.5, and 0≦a≦0.33,

wherein the molar ratio A of M to the total of Mn and M in the surface of the active material particles and the molar ratio B of M to the total of Mn and M in the whole active material particles satisfy the relations: A/B>1.0 and A≧0.3,

wherein, in an X-ray diffraction analysis using CuKα radiation as an X-ray source, the intensity ratio of the largest peak of peaks attributed to an oxide of the transition metal element M to a peak around 2θ=36.4° is 0.25 or less, and

the transition metal element M is at least one selected from the group consisting of Ni, Fe, Ti, Zr, and Cu.

2. The positive electrode material for a non-aqueous electrolyte secondary battery in accordance with claim 1 , wherein the molar ratios A and B satisfy the relations: A/B≧1.5 and 0<B≦0.22.

3. A non-aqueous electrolyte secondary battery comprising the positive electrode material of claim 1 .

4. The positive electrode material for a non-aqueous electrolyte secondary battery in accordance with claim 1 , wherein the transition metal element M is at least one selected from the group consisting of Ni, Fe, and Ti.

Assignments (2)
CHANGE OF NAME Recorded Nov 13, 2008
From: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
To: PANASONIC CORPORATION
Reel/Frame 021832/0197 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 17, 2008
From: YAMAMOTO, TERUAKI; WAKI, SHINICHI; BITO, YASUHIKO
To: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
Reel/Frame 021542/0872 →