Manganese/nickel composite oxide particles and process for producing the manganese nickel composite oxide particles, positive electrode active substance particles for non-aqueous electrolyte secondary batteries and process for producing the positive electrode active substance particles, and non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-11072869-B2
Application number	US-201816057982-A
Country	US
Kind code	B2
Filing date	Aug 8, 2018
Priority date	Mar 31, 2011
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

The present invention provides a precursor of positive electrode active substance particles for non-aqueous electrolyte secondary batteries which have a high discharge voltage and a high discharge capacity, hardly suffer from side reactions with an electrolyte solution, and are excellent in cycle characteristics, positive electrode active substance particles for non-aqueous electrolyte secondary batteries, and processes for producing these particles, and a non-aqueous electrolyte secondary battery. The present invention relates to positive electrode active substance particles for non-aqueous electrolyte secondary batteries having a spinel structure with a composition represented by the following chemical formula (1), in which the positive electrode active substance particles satisfy the following characteristic (A) and/or characteristic (B) when indexed with Fd-3m in X-ray diffraction thereof: (A) when indexed with Fd-3m in X-ray diffraction of the positive electrode active substance particles, a ratio of I(311) to I(111) [I(311)/I(111)] is in the range of 35 to 43%, and/or (B) when indexed with Fd-3m in X-ray diffraction of the positive electrode active substance particles, a gradient of a straight line determined by a least square method in a graph prepared by plotting sin θ in an abscissa thereof and B cos θ in an ordinate thereof wherein B is a full-width at half maximum with respect to each peak position 2θ (10 to 90°) is in the range of 3.0×10 −4 to 20.0×10 −4 ; and

Li 1+x Mn 2−y−z Ni y M z O 4   Chemical Formula (1)

wherein x, y, z fall within the range of −0.05·x·0.15, 0.4·y·0.6 and 0·z·0.20, respectively; and M is at least one element selected from the group consisting of Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W and Bi.

First claim

The invention claimed is:

1. Positive electrode active substance particles for non-aqueous electrolyte secondary batteries having a spinel structure with a composition represented by the following chemical formula (1):
Li 1+x Mn 2−y−z Ni y M z O 4   Chemical Formula (1):

wherein x, y, z fall within the range of −0.05≤x≤0.15, 0.4≤y≤0.6 and 0≤z≤0.20, respectively; and M is at least one element selected from the group consisting of Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W and Bi, and wherein
the positive electrode active substance particles have an average primary particle diameter of 1.0 to 4.0 μm,
an average secondary particle diameter (D50) of 4 to 30 μm, and
a BET specific surface area of 0.3 to 1.0 m 2 /g, and
wherein a multiplication product of the average secondary particle diameter (D50) times the BET specific surface area of the positive electrode active substance particles is less than or equal to 10.0×10 −6 m 3 /g, and
wherein the positive electrode active substance particles have a sodium content of 30 to 2000 ppm, a sulfur content of 10 to 600 ppm, and a total impurity content of not more than 5000 ppm.

2. The positive electrode active substance particles for non-aqueous electrolyte secondary batteries according to claim 1 , wherein a full-width at half maximum z of a peak of a (400) plane as measured in X-ray diffraction of the positive electrode active substance particles is in the range of z≤0.230°.

3. The positive electrode active substance particles for non-aqueous electrolyte secondary batteries according to claim 1 , wherein the positive electrode active substance particles have a tap density of not less than 1.7 g/mL (when tapped 500 times).

4. The positive electrode active substance particles for non-aqueous electrolyte secondary batteries according to claim 1 , wherein the positive electrode active substance particles have a sodium content of 40 to 1700 ppm, a sulfur content of 15 to 500 ppm and a total impurity content of not more than 3500 ppm.

5. The positive electrode active substance particles for non-aqueous electrolyte secondary batteries according to claim 1 , wherein the positive electrode active substance particles have an endotherm of 0.3 to 0.8 J/mg as measured by differential scanning calorimetry when heated from −40° C. to 70° C.

6. The positive electrode active substance particles for non-aqueous electrolyte secondary batteries according to claim 1 , wherein when subjecting a non-aqueous electrolyte secondary battery produced using the positive electrode active substance particles to initial charging, a ratio of (b−a)/b in which a represents a battery capacity when charged up to 4.8 V and b is a battery capacity when charged up to 5.0 V is less than 10%.

7. The positive electrode active substance particles for non-aqueous electrolyte secondary batteries according to claim 1 , wherein a non-aqueous electrolyte secondary battery produced using the positive electrode active substance particles has an initial charge/discharge efficiency of not less than 90%.

8. A process for producing the positive electrode active substance particles for non-aqueous electrolyte secondary batteries as defined in claim 1 , comprising the steps of mixing a composite compound comprising Mn and Ni as main components with an Li compound; subjecting the resulting mixture to calcination step (1) in an oxidative atmosphere at a temperature of 680 to 1050° C.; and successively subjecting the calcined product to calcination step (2) at a temperature of 500 to 700° C.

9. A non-aqueous electrolyte secondary battery using the positive electrode active substance particles as defined in claim 1 .

Assignees

• Toda Kogyo Corp

Inventors

• Watanabe Hiroyasu
• Morita Daisuke
• Yamamoto Manabu
• Koga Kazumichi
• Kajiyama Akihisa
• Masukuni Hiroaki
• Sadamura Hideaki
• Masaki Ryuta
• Matsumoto Kazutoshi

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• C30B1/02

  by thermal treatment, e.g. strain annealing (C30B1/12 takes precedence) · CPC title

• C01G45/1242 Primary

  of the type (Mn2O4)-, e.g. LiMn2O4 or Li(MxMn2-x)O4 · CPC title

• H01M4/505 Primary

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• Y10T428/2982

  Particulate matter [e.g., sphere, flake, etc.] · CPC title