Cathode active material for non-aqueous electrolyte secondary battery and manufacturing method for same, and non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-2016172673-A1
Application number	US-201414907087-A
Country	US
Kind code	A1
Filing date	Jul 22, 2014
Priority date	Jul 24, 2013
Publication date	Jun 16, 2016
Grant date	—

Abstract

Provided is a cathode active material for a non-aqueous electrolyte secondary battery, with which it is possible to improve the output characteristics during use in extremely low-temperature environments. A lithium compound is mixed with nickel cobalt manganese composite hydroxide particles that are expressed by the general formula: Ni x Co y Mn z M t (OH) 2 +a (where x+y+z+t=1, 0.30≦×≦0.70, 0.10 ≦y≦0.40, 0.10 ≦z≦0.40, 0≦t≦0.01, and M is one or more elements selected from Mg, Ca, Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W) such that the ratio of the number of lithium atoms to the total number of atoms of metal elements other than lithium is 1:0.95 to 1.20. The lithium mixture undergoes calcination in an oxidizing atmosphere so that the rate of temperature rise in a temperature range of at least 30° C. to 800° C. is 4° C. /min to 10° C./min, the calcination temperature is 800° C. to 1000° C., the maintenance time at the calcination temperature is 5 hours or less, and the time from the start of temperature rise to the end of the maintenance time is 3.0 hours to 7.0 hours.

First claim

What is claimed is:

1 . A cathode active material for a non-aqueous electrolyte secondary battery expressed by a general formula (A): Li 1+a Ni x Co y Mn z M t O 2 (where −0.05≦a≦0.20, x+y+z+t=1, 0.30≦x≦0.70, 0.10≦y≦0.40, 0.10≦z≦0.40, 0≦t≦0.01, and M is one or more element selected from among Ca, Mg, Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W), and includes layered hexagonal crystal lithium nickel cobalt manganese composite oxide particles; and the ratio of the integrated width of the diffraction peak on plane (104) with respect to the integrated width of the diffraction peak on plane (003) of the Miller indices (hkl) in powder X-ray diffraction that uses CuKα rays is 1.38 or greater.

2 . The cathode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein the ratio of the peak integrated intensity on plane (104) with respect to the peak integrated intensity on plane (003) of the Miller indices (hkl) in powder X-ray diffraction that uses CuKα rays is 1.20 or greater.

3 . The cathode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein the integrated width ratio is within the range of 1.39 to 1.49.

4 . The cathode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein the volume-average particle size that is found by a laser diffraction and scattering method is within the range of 3 μm to 20 μm.

5 . The cathode active material for a non-aqueous electrolyte secondary battery according to claim 1 , wherein the specific surface area is within the range of 0.3 m 2 /g to 2.5 m 2/ g.

6 . A manufacturing method for a cathode active material for a non-aqueous electrolyte secondary battery comprising:
a mixing process for obtaining a lithium mixture by mixing a lithium compound with nickel cobalt manganese composite hydroxide particles that are expressed by a general formula (B): Ni x Co y Mn z M t (OH) 2+ α (where x+y+z+t=1, 0.30≦x≦0.70, 0.10≦y 0.40, 0.10≦z≦0.40, 0≦t≦0.01, and M is one or more element selected from among Mg, Ca, Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W) so that the ratio of the number of atoms of lithium with respect to the total number of atoms of metal elements other than lithium is 1:0.95 to 1.20; and a calcination process of performing calcination of the lithium mixture in an oxidizing atmosphere where the rate of temperature rise in at least the temperature range from 30° C. to 800° C. is 4° C./min to 10° C./min, the calcination temperature is 800° C. to 1000° C., the maintenance time at the calcination temperature is 5 hours or less, and time from the start of temperature rise to the end of the maintenance time is 3.0 hours to 7 hours.

7 . The manufacturing method for a cathode active material for a non-aqueous electrolyte secondary battery according to claim 6 , further comprising
a heat-treatment process before the mixing process for heat treating the nickel cobalt manganese composite hydroxide particles to 105° C. to 400° C. to obtain heat-treated particles.

8 . The manufacturing method for a cathode active material for a non-aqueous electrolyte secondary battery according to claim 6 , wherein lithium carbonate, lithium hydroxide or a mixture of these is used as the lithium compound.

9 . The manufacturing method for a cathode active material for a non-aqueous electrolyte secondary battery according to claim 6 , wherein the oxygen concentration in the oxidizing atmosphere is 10% by volume to 100% by volume.

10 . The manufacturing method for a cathode active material for a non-aqueous electrolyte secondary battery according to claim 6 , further comprising
a crushing process after the calcination process for crushing the lithium nickel cobalt manganese composite particles that were obtained in the calcination process.

11 . A non-aqueous electrolyte secondary battery comprising a cathode, an anode, a separator and a non-aqueous electrolyte, wherein the cathode active material for a non-aqueous electrolyte according to claim 1 is used as the cathode material of the cathode.

12 . The non-aqueous electrolyte secondary battery according to claim 11 , wherein the initial discharge capacity is 150 mAh/g or greater, and the extremely low-temperature output at −30° C. is 110 W or greater.

Assignees

• Sumitomo Metal Mining Co
• Toyota Motor Co Ltd

Inventors

• Toya Hiroyuki
• Morita Masahiro
• Nagai Hiroki
• Makimura Yoshinari
• Kobayashi Tetsuro

Classifications

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title

• H01M2004/028

  Positive electrodes · 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

• C01P2006/40

  Electric properties · CPC title

• H01M10/0525

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