Battery electrode and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-2021104719-A1
Application number	US-202016951149-A
Country	US
Kind code	A1
Filing date	Nov 18, 2020
Priority date	Jun 11, 2018
Publication date	Apr 8, 2021
Grant date	—

Abstract

There is provided a method for manufacturing a battery electrode. The method includes: forming a precursor of the battery electrode including a double-sided coating area in which both sides of a current collector are coated with an electrode material layer and a single-sided coating area adjacent to the double-sided coating area; subjecting the current collector located at a boundary portion between the double-sided coating area and the single-sided coating area to a heat treatment locally; and pressurizing the precursor of the battery electrode. The single-sided coating area includes a main side of the current collector that is coated with the electrode material layer.

First claim

1 . A method for manufacturing a battery electrode, the method comprising steps of:
forming a precursor of the battery electrode including a double-sided coating area in which both sides of a current collector are coated with an electrode material layer and a single-sided coating area adjacent to the double-sided coating area, wherein the single-sided coating area includes a main side of the current collector that is coated with the electrode material laver; subjecting the current collector located at a boundary portion between the double-sided coating area and the single-sided coating area to a heat treatment locally; and pressurizing the precursor of the battery electrode.

2 . The method according to claim 1 , wherein the current collector located at the boundary portion is locally softened by the heat treatment.

3 . The method according to claim 1 , wherein the current collector located at the boundary portion has a curved area increased by the heat treatment to be larger than the current collector that is not subjected to the heat treatment.

4 . The method according to claim 1 ,
wherein the precursor of the battery electrode is pressurized using a pair of press rolls positioned to sandwich the precursor, and a spatial area formed between the current collector located at the boundary portion and the press roll directly facing the current collector has a size reduced by the heat treatment to he smaller than the current collector that is not subjected to the heat treatment.

5 . The method according to claim 1 , wherein a Young's modulus of the current collector located at the boundary portion by the heat treatment is lower than a Young's modulus of the current collector located at a portion other than the boundary portion.

6 . The method according to claim 5 , wherein the Young's modulus of the current collector located at the boundary portion is 50% or more lower than the Young's modulus of the current collector located at the portion other than the boundary portion.

7 . The method according to claim 1 , wherein the heat treatment is performed, as a non-contact heat treatment, without contact with the current collector located at the boundary portion and the electrode material layer.

8 . The method according to claim 7 , wherein the non-contact heat treatment is performed using a high-frequency induction heating device.

9 . The method according to claim 8 , wherein the high-frequency induction heating device is driven when the high-frequency induction heating device faces the current collector located at the boundary portion.

10 . The method according to claim 1 , wherein after pressurizing the precursor of the battery electrode, a ratio of a volume density of the electrode material layer located at the boundary portion (A) to a volume density of the electrode material layer located at the portion other than the boundary portion (B) is from 0.9 to 1.0.

11 . The method according to claim 1 , wherein after pressurizing the precursor of the battery electrode, the electrode material layer located at the boundary portion has a low volume density area with a size lower than the current collector that is not subjected to the heat treatment.

12 . A battery electrode comprising:
a double-sided coating area including a current collector and an electrode material layer with which both sides of the current collector are coated; and a single-sided coating area adjacent to the double-sided coating area, wherein the single-sided coating area includes the current collector and the electrode material layer with which one side of the current collector is coated, wherein the current collector located at a boundary portion between the double-sided coating area and the single-sided coating area has a Young's modulus lower than a Young's modulus of the current collector located at a portion other than the boundary portion.

13 . The battery electrode according to claim 12 , wherein the Young's modulus of the current collector located at the boundary portion is 50% or more lower than the Young's modulus of the current collector located at the portion other than the boundary portion.

14 . The battery electrode according to claim 12 , wherein a ratio of a volume density of the electrode material layer located at the boundary portion (A) to a volume density of the electrode material layer located at the portion other than the boundary portion (B) is from 0.9 to 1.0.

15 . The battery electrode according to claim 13 , wherein a ratio of a volume density of the electrode material layer located at the boundary portion (A) to a volume density of the electrode material layer located at the portion other than the boundary portion (B) is from 0.9 to 1.0.

Assignees

• Murata Manufacturing Co

Inventors

• Oikawa Makiko

Classifications

• H01M2004/021

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

• H01M4/02

  Electrodes composed of, or comprising, active material · CPC title

• H01M4/0404 Primary

  by coating on electrode collectors · CPC title

• H01M4/0435

  Rolling or calendering · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title