Cathode including sintered polycrystalline material, secondary battery including the cathode, and method of manufacturing the cathode

Patent metadata

Field	Value
Publication number	US-10147944-B2
Application number	US-201615047740-A
Country	US
Kind code	B2
Filing date	Feb 19, 2016
Priority date	Aug 4, 2015
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

A cathode includes a cathode collector layer, and a cathode active material layer on a surface of the cathode collector layer. The cathode active material layer includes a sintered polycrystalline material having a plurality of crystal grains of a lithium-based oxide, and each of the plurality of crystal grains includes a seed template, and a matrix crystal around the seed template, where the seed template is a single crystal and having a shape of a plate.

First claim

What is claimed is:

1. A cathode comprising:
a cathode collector layer; and
a cathode active material layer on a surface of the cathode collector layer,
wherein the cathode active material layer comprises a sintered polycrystalline material having a plurality of crystal grains of a lithium-based oxide, and
each of the plurality of crystal grains comprises:
a seed template; and
a matrix crystal around the seed template,
wherein the seed template is a single crystal and having a shape of a plate.

2. The cathode of claim 1 , wherein a surface of the seed template having the shape of the plate, which faces a surface of the cathode collector layer, is substantially parallel to the surface of the cathode collector layer.

3. The cathode of claim 1 , wherein an acute angle between a surface of the seed template having the shape of the plate, which faces a surface of the cathode collector layer, and a surface of the cathode collector layer is in a range of about ±45°.

4. The cathode of claim 1 , wherein the seed template and the matrix crystal have different compositions from each other.

5. The cathode of claim 1 , wherein the plurality of crystal grains are oriented in a way such that an acute angle between a direction perpendicular to a surface of the cathode collector layer and a direction of lithium planes defined by lithium elements in layers in each of the plurality of crystal grains is in a range of about ±45°.

6. The cathode of claim 1 , wherein some of the plurality of crystal grains are oriented in a way such that a lithium plane defined by lithium elements in layers in each of the plurality of crystal grains is substantially perpendicular to a surface of the cathode collector layer.

7. The cathode of claim 1 , wherein
a crystal direction of the plurality of crystal grains perpendicular to a surface of the cathode collector layer comprises at least one of directions <h00>, <0k0>, <hk0>, <101>, <012>, <104>, <113>, <021>, and <024>, wherein “h” and “k” are integers equal to or greater than 1.

8. The cathode of claim 1 , wherein
the lithium-based oxide comprises Li x MO 2 ,
wherein “M” is at least one of cobalt (Co), nickel (Ni), manganese (Mn), and
“x” is in a range of 0.2<x<1.2.

9. The cathode of claim 1 , wherein the cathode active material layer directly contacts the cathode collector layer.

10. A secondary battery comprising:
an anode collector layer;
an anode active material layer on a surface of the anode collector layer;
a cathode collector layer; and
a cathode active material layer on a surface of the cathode collector layer,
wherein the cathode active material layer comprises a sintered polycrystalline material having a plurality of crystal grains of a lithium-based oxide, and
each of the plurality of crystal grains comprises:
a seed template; and
a matrix crystal around the seed template,
wherein the seed template is a single crystal and having a shape of a plate.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Cho Kyunghoon
• Nam Seunghoon
• Park Hwiyeol
• Yang Hojung
• Jeong Huisu
• Heo Jin S

Classifications

• H01M2300/0068

  inorganic · CPC title

• H01M10/0583

  of accumulators with folded construction elements except wound ones, i.e. folded positive or negative electrodes or separators, e.g. with "Z"-shaped electrodes or separators · CPC title

• H01M10/0562

  Solid materials · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/64

  Carriers or collectors · CPC title