Positive active material for rechargeable lithium battery, method of preparing same and rechargeable lithium battery including same

Patent metadata

Field	Value
Publication number	US-2017200951-A1
Application number	US-201715401188-A
Country	US
Kind code	A1
Filing date	Jan 9, 2017
Priority date	Jan 13, 2016
Publication date	Jul 13, 2017
Grant date	—

Abstract

A positive active material for a rechargeable lithium battery including a lithium metal compound and a phosphorus (P)-containing compound on the surface of the lithium metal compound. A content of phosphorus (P) of the phosphorus-containing compound is about 0.1 atom % to about 10 atom % based on the total amount of elements on the surface of the positive active material. A method of preparing the same and rechargeable lithium battery including the same are also provided.

First claim

What is claimed is:

1 . A positive active material for a rechargeable lithium battery, the positive active material comprising a lithium metal compound and a phosphorus (P)-containing compound on the surface of the lithium metal compound,
wherein a content of phosphorus (P) of the phosphorus-containing compound is about 0.1 atom % to about 10 atom % based on the total amount of elements on the surface of the positive active material.

2 . The positive active material as claimed in claim 1 , wherein the phosphorus-containing compound includes lithium phosphate.

3 . The positive active material as claimed in claim 1 , wherein the phosphorus-containing compound includes Li 3 PO 4 , Li 2 HPO 4 , LiH 2 PO 4 , LiMPO 4 , where M=Fe, Co, Mn, Ni, V, La, Ti, or Al, (NH 4 ) 2 HPO 4 , (NH 4 )H 2 PO 4 , AlPO 4 , H 3 PO 4 , or a combination thereof.

4 . The positive active material as claimed in claim 1 , wherein the lithium metal compound includes a lithium nickel-based oxide represented by Chemical Formula 1:
Li x Ni y M z O 2   [Chemical Formula 1]
wherein, M is Co, Mn, Al, Mg, Ti, Zr, or a combination thereof, 0.95≦x≦1.00, 0.4≦y≦1.00, 0≦z≦0.6, and y+z=1.

5 . A method of preparing a positive active material for a rechargeable lithium battery, the method comprising
washing a first active material with an aqueous solution of a phosphorus (P)-containing material to obtain a second active material, wherein the first active material includes a lithium metal compound and a lithium compound present on the surface of the lithium metal compound, the lithium metal compound being different from the lithium compound, and the second active material includes the lithium metal compound and a phosphorus-containing compound present on the surface of the lithium metal compound.

6 . The method as claimed in claim 5 , wherein the aqueous solution of the phosphorus-containing material is an aqueous solution including a phosphoric acid, a phosphate salt, or a combination thereof.

7 . The method as claimed in claim 6 , wherein the aqueous solution of the phosphorus-containing material is the aqueous solution including the phosphate salt, and
the phosphate salt includes Li 2 HPO 4 , LiH 2 PO 4 , LiMPO 4 , where M=Fe, Co, Mn, Ni, V, La, Ti, or Al, (NH 4 ) 2 HPO 4 , (NH 4 )H 2 PO 4 , AlPO 4 , H 3 PO 4 , or a combination thereof.

8 . The method as claimed in claim 5 , wherein the phosphorus-containing material is used in an amount of about 0.01 parts by mole to about 20 parts by mole based on 100 parts by mole of the first active material.

9 . The method as claimed in claim 5 , wherein a concentration of the phosphorus-containing aqueous solution is about 0.01 M to about 10 M.

10 . The method as claimed in claim 5 , wherein the lithium metal compound includes a lithium nickel-based oxide represented by Chemical Formula 1:
Li x Ni y M z O 2   [Chemical Formula 1]
wherein, M is Co, Mn, Al, Mg, Ti, Zr, or a combination thereof, 0.95≦x≦1.00, 0.4≦y≦1.00, 0≦z≦0.6, and y+z=1.

11 . The method as claimed in claim 5 , wherein the lithium compound includes Li 2 CO 3 , LiOH, or a combination thereof.

12 . A rechargeable lithium battery comprising the positive electrode including a positive active material as claimed in claim 1 .

Assignees

• Samsung Sdi Co Ltd

Inventors

• Hong Ming-Zi
• Kim Ki-Hyun
• Park Do-Hyung
• Han Jung-Min
• Lee Jae-Ho

Classifications

• H01M4/366

  as layered products · 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

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/628 Primary

  Inhibitors, e.g. gassing inhibitors, corrosion inhibitors · CPC title

• H01M10/0525

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