Current collector, secondary battery, electronic device, and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-2015243962-A1
Application number	US-201514617472-A
Country	US
Kind code	A1
Filing date	Feb 9, 2015
Priority date	Feb 21, 2014
Publication date	Aug 27, 2015
Grant date	—

Abstract

An object is to provide a secondary battery suitable for a wearable device. Another object is to provide a novel power storage device. Part of an electrode, specifically a current collector and an active material layer, for a secondary battery is subjected to cutting processing to have a complex shape. This suppresses the positional shift of an end portion of an electrode far from a curvature center from an electrode close to the curvature center due to the larger degree of bending of the electrode far from the curvature center than that of the electrode close to the curvature center, or relieves tension to be applied to the electrode far from the curvature center.

First claim

1 . An electrode comprising:
a current collector; an active material layer over the current collector; and a first slit passing the current collector and the active material layer, the first slit extending to an edge of each of the current collector and the active material layer.

2 . The electrode according to claim 1 , further comprising:
a second slit passing the current collector and the active material layer.

3 . The electrode according to claim 2 , wherein an angle between the first slit and the second slit is less than 90 degrees.

4 . The electrode according to claim 2 , wherein the second slit extends to an opposite edge of each of the current collector and the active material layer with respect to the edge.

5 . A battery comprising the electrode according to claim 1 .

6 . An electronic device comprising:
the battery according to claim 5 ; and a display portion.

7 . A battery comprising:
a first electrode comprising:
a first current collector;
a first active material layer over the first current collector; and
a first slit passing the first current collector and the first active material layer, the first slit extending to an edge of each of the first current collector and the first active material layer; and
a second electrode comprising:
a second current collector; and
a second active material layer over the second current collector.

8 . The battery according to claim 7 , further comprising:
a second slit passing the first current collector and the first active material layer.

9 . The battery according to claim 8 , wherein an angle between the first slit and the second slit is less than 90 degrees.

10 . The battery according to claim 8 , wherein the second slit extends to an opposite edge of each of the first current collector and the first active material layer with respect to the edge.

11 . The battery according to claim 7 , further comprising:
a second slit passing the second current collector and the second active material layer.

12 . The battery according to claim 11 , wherein a total number of slits in the first electrode is different from a total number of slits in the second electrode.

13 . The battery according to claim 7 , further comprising:
a separator; and an electrolytic solution.

14 . The battery according to claim 7 ,
wherein the first electrode is a positive electrode, and wherein the second electrode is a negative electrode.

15 . An electronic device comprising:
the battery according to claim 7 ; and a display portion.

16 . A method for manufacturing an electrode comprising:
forming an active material layer over a current collector; and processing the current collector and the active material layer to form a first slit passing the current collector and the active material layer so as to extend to an edge of each of the current collector and the active material layer.

17 . The method according to claim 16 , further comprising a step of processing the current collector and the active material layer to form a second slit passing the current collector and the active material layer.

18 . The method according to claim 17 , wherein an angle between the first slit and the second slit is less than 90 degrees.

19 . The method according to claim 17 , wherein the second slit is formed so as to extend to an opposite edge of each of the current collector and the active material layer with respect to the edge.

20 . The method according to claim 16 , wherein the first slit is formed using laser light.

Assignees

• Semiconductor Energy Lab

Inventors

• Hiroki Masaaki
• Tajima Ryota

Classifications

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M4/0404 Primary

  by coating on electrode collectors · CPC title

• H01M4/139

  Processes of manufacture · CPC title

• H01M4/02 Primary

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

• H01M2004/021

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