Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2016172671-A1
Application number	US-201514967845-A
Country	US
Kind code	A1
Filing date	Dec 14, 2015
Priority date	Dec 16, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

The present invention relates to a lithium secondary battery, and more specifically, to a lithium secondary battery including a cathode, an anode and a non-aqueous electrolyte solution, where the cathode includes a cathode active material including a lithium-metal oxide which is doped with a transition metal and includes at least one type of metal having a concentration gradient region between a central portion and a surface portion, and thus having a significantly increased charge/discharge capacity and output at a low temperature to exhibit excellent properties in the low-temperature environment.

First claim

What is claimed is:

1 . A lithium secondary battery, comprising:
a cathode; an anode; and a non-aqueous electrolyte solution, wherein the cathode includes a cathode active material including a lithium-metal oxide which is doped with a transition metal and includes at least one type of metal having a concentration gradient region between a central portion and a surface portion.

2 . The lithium secondary battery of claim 1 , wherein the transition metal is one or more selected from the group consisting of Ti, Zr, Mg, Al, V, B, Na, Ca, Cr, Cu, Zn, Ge, Sr, Ba, Nb and Ga.

3 . The lithium secondary battery of claim 1 , wherein a concentration of the transition metal as a dopant ranges from 500 to 7,000 ppm.

4 . The lithium secondary battery of claim 1 , wherein a concentration of the transition metal as a dopant ranges from 500 to 3,000 ppm.

5 . The lithium secondary battery of claim 1 , wherein the lithium-metal oxide further includes Al, Ti, Ba, Zr, Si, B, Mg, P, alloys thereof or a coating layer of oxides thereof at a surface of the lithium-metal oxide.

6 . The lithium secondary battery of claim 1 , wherein another type of metal among metals forming the lithium-metal oxide has a uniform concentration between a central portion and a surface portion.

7 . The lithium secondary battery of claim 1 , wherein the lithium-metal oxide includes:
a first metal, having a concentration gradient region in which a concentration increases between the central portion and the surface portion; and a second metal, having a concentration gradient region in which a concentration decreases between the central portion and the surface portion.

8 . The lithium secondary battery of claim 1 , wherein the lithium-metal oxide is represented by the following Formula 1, and at least one of M1, M2 and M3 has a concentration gradient region between the central portion and the surface portion in the following Formula 1:
Li x M1 a M2 b M3 c O y   [Formula 1]
(where M1, M2 and M3 are selected from the group consisting of Ni, Co, Mn, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga and B, and 0<x≦1.1, 2≦y≦2.02, 0≦a≦1, 0≦b≦1, 0≦c≦1, 0<a+b+c≦1).

9 . The lithium secondary battery of claim 8 , wherein at least one of the M1, M2 and M3 has a concentration gradient region in which a concentration increases between the central portion and the surface portion, and the remainder has/have a concentration gradient region in which a concentration decreases between the central portion and the surface portion.

10 . The lithium secondary battery of claim 8 , wherein one of the M1, M2 and M3 has a concentration gradient region in which a concentration increases between the central portion and the surface portion, another one has a concentration gradient region in which a concentration decreases between the central portion and the surface portion, and the other one has a uniform concentration between the central portion and the surface portion.

11 . The lithium secondary battery of claim 8 , wherein the M1, M2 and M3 are Ni, Co and Mn, respectively.

12 . The lithium secondary battery of claim 8 , wherein the M1 is Ni, and 0.6≦a≦0.95 and 0.05≦b+c≦0.4.

13 . The lithium secondary battery of claim 8 , wherein the M1 is Ni, and 0.7≦a≦0.9 and 0.1≦b+c≦0.3.

14 . The lithium secondary battery of claim 1 , wherein primary particles including the lithium-metal oxide are rod-type particles.

Assignees

• Sk Innovation Co Ltd

Inventors

• Yoo Kyung-Bin
• Han Kook-Hyun
• Hwang Duck-Chul

Classifications

• 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

• H01M4/505

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

• C01P2002/54

  one element only · CPC title

• C01P2002/52

  containing elements as dopants · CPC title

• C01P2004/61

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