Positive electrode for rechargeable lithium battery and rechargeable lithium battery including the same

Patent metadata

Field	Value
Publication number	US-2017346133-A1
Application number	US-201715608812-A
Country	US
Kind code	A1
Filing date	May 30, 2017
Priority date	May 30, 2016
Publication date	Nov 30, 2017
Grant date	—

Abstract

The present invention relates to a positive electrode for a rechargeable lithium battery and a rechargeable lithium battery including the same. The positive electrode includes: a current collector; and a positive electrode active material positioned on at least one surface of the active material layer current collector. The positive electrode active material layer includes a small particle size active material having an average particle diameter D50 of 2 μm to 4 μm and a first coating layer positioned at a surface thereof, and a large particle size active material having an average particle diameter D50 of 17 μm to 21 μm and a second coating layer positioned at the surface thereof.

First claim

What is claimed is:

1 . A positive electrode for a rechargeable lithium battery, comprising:
a current collector; and a positive electrode active material layer on at least one surface of the current collector, wherein the positive electrode active material layer comprises: a small particle size active material having an average particle diameter D50 of 2 μm to 4 μm and a first coating layer at a surface thereof, and a large particle size active material having an average particle diameter D50 of 17 μm to 21 μm and a second coating layer at a surface thereof.

2 . The positive electrode of claim 1 , wherein
at least one of the first coating layer and the second coating layer comprises at least one material selected from the group consisting of Al, Ti, Mg, Co, K, Na, Ca, Si, V, Sn, Ge, Ga, B, As, and Zr.

3 . The positive electrode of claim 1 , wherein
at least one of the first coating layer and the second coating layer comprises Al and Ti.

4 . The positive electrode of claim 3 , wherein
in the at least one of the first coating layer and the second coating layer: an Al mol % is in a range of 0.01 to 1, and a Ti mol % is in a range of 0.01 to 1.

5 . The positive electrode of claim 1 , wherein
a content ratio of the large particle size active material to the small particle size active material is in a range of 75:25 to 95:5.

6 . The positive electrode of claim 1 , wherein
the positive electrode active material is at least one selected from the group consisting of a lithium-nickel-containing oxide, a lithium-cobalt-containing oxide, a lithium-iron-phosphate-containing oxide, a lithium-manganese-containing oxide, a lithium-titanium-containing oxide, a lithium-nickel-manganese-containing oxide, a lithium-nickel-cobalt-manganese-containing oxide, a lithium-nickel-cobalt-aluminum-containing oxide, and combinations thereof.

7 . The positive electrode of claim 1 , wherein
an active mass density of the positive electrode for the rechargeable lithium battery is 4.2 g/cc or more.

8 . The positive electrode of claim 1 , wherein
a thickness of the active material layer is greater than 0 to 200 μm or less.

9 . A rechargeable lithium battery comprising:
the positive electrode of claim 1 ; a negative electrode; and an electrolyte.

10 . The rechargeable lithium battery of claim 9 , wherein
at least one of the first coating layer and the second coating layer comprises at least one material selected from the group consisting of Al, Ti, Mg, Co, K, Na, Ca, Si, V, Sn, Ge, Ga, B, As, and Zr.

11 . The rechargeable lithium battery of claim 9 , wherein
at least one of the first coating layer and the second coating layer comprises Al and Ti.

12 . The rechargeable lithium battery of claim 9 , wherein
in the at least one of the first coating layer and the second coating layer: an Al mol % is in a range of 0.01 to 1, and a Ti mol % is in a range of 0.01 to 1.

13 . The rechargeable lithium battery of claim 9 , wherein
a content ratio of the large particle size active material to the small particle size active material is in a range of 75:25 to 95:5.

14 . The rechargeable lithium battery of claim 9 , wherein
the positive electrode active material is at least one selected from the group consisting of a lithium-nickel-containing oxide, a lithium-cobalt-containing oxide, a lithium-iron-phosphate-containing oxide, a lithium-manganese-containing oxide, a lithium-titanium-containing oxide, a lithium-nickel-manganese-containing oxide, a lithium-nickel-cobalt-manganese-containing oxide, a lithium-nickel-cobalt-aluminum-containing oxide, and combinations thereof.

15 . The rechargeable lithium battery of claim 9 , wherein
an active mass density of the positive electrode for the rechargeable lithium battery is 4.2 g/cc or more.

16 . The rechargeable lithium battery of claim 9 , wherein
a thickness of the active material layer is greater than 0 to 200 μm or less.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Je Hyun-Joo
• Kim Jeong-Hoon
• Kim Ji-Hyun
• Park Soo-Youn
• Kim Chang-Wook

Classifications

• H01M10/0587

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M10/052

  Li-accumulators · CPC title