Negative electrode active material having high output characteristics and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-2020313158-A1
Application number	US-201816311110-A
Country	US
Kind code	A1
Filing date	Mar 21, 2018
Priority date	Mar 21, 2017
Publication date	Oct 1, 2020
Grant date	—

Abstract

Disclosed are a negative electrode active material including lithium titanium oxide particles, wherein the lithium titanium oxide particles have an average particle diameter (D50) of 0.5-9 μm, a specific surface area of 3-7 m2/g, and a pellet density of 1.7 g/cc or more under a pressure of 64 MPa, and a lithium secondary battery including the same.

First claim

1 . A negative electrode active material comprising:
lithium titanium oxide particles, wherein the lithium titanium oxide particles have an average particle diameter (D 50 ) of 0.5-9 μm, a specific surface area of 3-7 m 2 /g, and a pellet density of 1.7 g/cc or more under a pressure of 64 MPa, and the lithium titanium oxide is represented by the following Chemical Formula 1:
Li x Ti y O z M w   [Chemical Formula 1]

wherein M is any one selected from the group consisting of Zr, B, Sn, S, Be, Ge and Zn, or a combination of two or more of them, 0.5≤x≤5, 1≤y≤5, 2≤z≤12, and 0≤w<0.1.

2 . The negative electrode active material according to claim 1 , wherein the lithium titanium oxide particles are at least one selected from primary particles and secondary particles formed of the primary particles.

3 . The negative electrode active material according to claim 2 , wherein the primary particles have an average particle diameter (D 50 ) of 0.2-1.2 μm and a specific surface area of 5-7 m 2 /g.

4 . The negative electrode active material according to claim 3 , wherein the primary particles have a pellet density of 1.7-1.82 g/cc under a pressure of 64 MPa.

5 . The negative electrode active material according to claim 2 , wherein the secondary particles have an average particle diameter (D 50 ) of 2-9 μm and a specific surface area of 3-4.9 m 2 /g.

6 . The negative electrode active material according to claim 5 , wherein the secondary particles have a pellet density of 1.75-1.85 g/cc under a pressure of 64 MPa.

7 . The negative electrode active material according to claim 2 , wherein the lithium titanium oxide particles are a mixture of primary particles with secondary particles, and a weight ratio of the primary particles to the secondary particles is between 1:9 and 4:6.

8 . The negative electrode active material according to claim 1 , wherein the lithium titanium oxide is at least one selected from the group consisting of Li 0.8 Ti 2.2 O 4 , Li 2.67 Ti 1.33 O 4 , Li 1.33 Ti 1.67 O 4 , Li 1.14 Ti 1.71 O 4 , Li 4 Ti 5 O 12 , LiTi 2 O 4 and Li 2 TiO 3 .

9 . The negative electrode active material according to claim 1 , which further comprises any one active material particles selected from the group consisting of: a carbonaceous material; metal (Me); alloy including the metal (Me); oxide (MeOx) of the metal (Me); and a composite of the metal (Me) with carbon, or a combination of two or more of them.

10 . A lithium secondary battery which comprises
a positive electrode comprising a positive electrode active material, a negative electrode comprising a negative electrode active material, a separator interposed between the positive electrode and the negative electrode, and an electrolyte, wherein the negative electrode active material is the negative electrode active material as defined in claim 1 .

11 . The negative electrode active material according to claim 9 , wherein the metal (Me) is one or more of Si, Sn, Li, Zn, Mg, Cd, Ce, Ni or Fe.

Assignees

• Lg Chemical Ltd

Inventors

• Lee Bo-Ram
• Park Sung-Bin
• Park Ji-Young
• Jo Chi-Ho
• Han Jung-Min
• Hur Hyuck
• Jung Wang-Mo

Classifications

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/36

  Selection of substances as active materials, active masses, active liquids · CPC title

• 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

• H01M10/0525

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