Positive electrode active material for non-aqueous electrolyte secondary battery and method for producing same

Patent metadata

Field	Value
Publication number	US-11658295-B2
Application number	US-201916577022-A
Country	US
Kind code	B2
Filing date	Sep 20, 2019
Priority date	Mar 31, 2017
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

This cathode active material for a secondary battery using a non-aqueous electrolyte includes nickel-rich lithium transition-metal oxide, exhibits a hard X-ray photoelectron spectroscopy (HAXPES) peak of 1,560 to 1,565 eV in binding energy from an Al-rich layer, using a photon energy of 6 KeV, and with respect to the mean particle diameter r of the lithium transition-metal oxide particle, the Al concentration is approximately constant within 0.35r of the center.

First claim

The invention claimed is:

1. A positive electrode active material for a non-aqueous electrolyte secondary battery, including a nickel-containing lithium transition metal oxide represented by a formula (1), wherein
a peak of 1560 to 1565 eV in binding energy from an Al-rich layer exists in hard X-ray photoelectron spectroscopy (HAXPES) at a photon energy of 6 KeV, and when lithium transition metal oxide particles have an average particle diameter of r, an Al concentration is approximately constant within a range of 0.35r from the center:
Li x Ni a Co b Al c M d O 2   (Formula 1),

wherein x, a, b, c, and d meet 0.95<x<1.05, 0.91≤a<1, 0<b<0.15, 0≤d<0.15, and 0.03<c, and M represents at least one metal element selected from the group consisting of B, Si, Mg, Ge, Sn, Mg, Cr, Mn, Ti, Nb, Mo, and Fe,
wherein the Al-rich layer is a mixed body of LiAlO 2 and an oxide containing Li, Ni, Co, and Al,
wherein the Al-rich layer has a thickness of 100 nm or less,
wherein the Al concentration within the range of 0.35r from the center is 3 mol % or more, and
wherein the Al concentration of the lithium transition metal oxide particles meets 0.99<(Al concentration at 0.35r)/(Al concentration at central portion)<1.01.

2. The positive electrode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein the Al-rich layer contains LiAlO 2 .

3. The positive electrode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein aluminum is dissolved to form a solid solution inside the lithium transition metal oxide particles.

4. A method for producing the positive electrode active material for a non-aqueous secondary battery of claim 1 , the positive electrode active material including the nickel-containing lithium transition metal oxide, the method including the steps of:
mixing a nickel cobalt aluminum-containing oxide carrying lithium hydroxide or lithium carbonate on a surface thereof with an Al compound; and
heating the nickel cobalt aluminum-containing oxide and the Al compound at 500° C. to 800° C.

Assignees

• Panasonic Corp
• Sanyo Electric Co
• Panasonic Holdings Corp

Inventors

• MIZAWA Miki
• Nagata Kaoru
• Maekawa Masanori
• Kinoshita Masahiro

Classifications

• H01M4/364

  as mixtures · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M4/5825

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

• H01M4/48

  of inorganic oxides or hydroxides · CPC title

• H01M4/485 Primary

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title