Electrode for electrochemical device, electrochemical device, and method for manufacturing same

Patent metadata

Field	Value
Publication number	US-2020067081-A1
Application number	US-201716345989-A
Country	US
Kind code	A1
Filing date	Oct 31, 2017
Priority date	Oct 31, 2016
Publication date	Feb 27, 2020
Grant date	—

Abstract

An electrode for an electrochemical device has a coated portion in which an active material layer is formed on a current collector; a non-coated portion in which the active material layer is not formed; and a resin layer that is laminated such that the coated portion and a portion of the non-coated portion are covered; wherein: the resin layer has a high-permeability portion having high ion permeability and positioned on the coated portion; a low-permeability portion having low ion permeability and positioned on a portion of the non-coated portion; and a transition portion in which ion permeability decreases from the high-permeability portion side toward the low-permeability portion side and positioned between the high-permeability portion and the low-permeability portion.

First claim

1 . An electrode for an electrochemical device comprising:
a coated portion in which an active material layer is formed on a current collector; a non-coated portion in which the active material layer is not formed; and a resin layer that is laminated such that the coated portion and a portion of the non-coated portion are covered; wherein:
the resin layer has a high-permeability portion having high ion permeability and positioned on the coated portion;
a low-permeability portion having low ion permeability and positioned on a portion of the non-coated portion; and a transition portion in which ion permeability decreases from the high-permeability portion side toward the low-permeability portion side and positioned between the high-permeability portion and the low-permeability portion.

2 . The electrode according to claim 1 ,
wherein the volume resistivity of the resin layer is at least 1×10 12 Ω·cm.

3 . The electrode according to claim 1 ,
wherein the layer thickness of the high-permeability portion is thin, the layer thickness of the low-permeability portion is thick, and the layer thickness of the transition portion increases from the high-permeability portion side toward the low-permeability portion side.

4 . The electrode according to claim 1 ,
wherein the insulation resistance of the high-permeability portion is low, the insulation resistance of the low-permeability portion is high, and the insulation resistance of the transition portion increases from the high-permeability portion side toward the low-permeability portion side.

5 . The electrode according to claim 1 ,
wherein the density of the high-permeability portion is low, the density of the low-permeability portion is high, and the density of the transition portion increases from the high-permeability portion side toward the low-permeability portion side.

6 . The electrode according to claim 1 ,
wherein the end portion of the coated portion is formed in an inclined-plane shape, and the transition portion is formed over an inclined-plane shaped portion.

7 . The electrode according to claim 1 ,
wherein the resin layer contains an insulating material.

8 . The electrode according to claim 7 ,
wherein the insulating material is alumina powder.

9 . The electrode according to claim 1 ,
wherein a portion of the non-coated portion and that is not covered by the resin layer is an electrode tab that is connected to an electrode terminal.

10 . An electrochemical device comprising:
a multilayered electrode body in which the electrode according to claim 1 is used as positive electrodes, negative electrodes, or both the positive electrodes and the negative electrodes, and the positive electrodes and the negative electrodes are alternately laminated with separators interposed therebetween; and an external container that accommodates the multilayered electrode body and an electrolyte.

11 . A method of manufacturing an electrode for an electrochemical device, the method comprising steps of:
forming an active material layer on a portion of a current collector to provide a coated portion in which the active material layer is formed on the current collector and a non-coated portion in which the active material layer is not formed; and laminating a resin layer to cover the coated portion and a portion of the non-coated portion; wherein, in the step of laminating the resin layer,
a high-permeability portion having high ion permeability and positioned on the coated portion,
a low-permeability portion having low ion permeability and positioned on a portion of the non-coated portion,
and a transition portion in which ion permeability decreases from the high-permeability portion side toward the low-permeability portion side and which is positioned between the high- permeability portion and the low-permeability portion, are formed as the resin layer.

12 . The method of manufacturing an electrode according to claim 11 ,
wherein the high-permeability portion, the low-permeability portion and the transition portion are formed such that the layer thickness of the high-permeability portion is thin, the layer thickness of the low-permeability portion is thick, and the layer thickness of the transition portion increases from the high-permeability portion side toward the low-permeability portion side.

13 . The method of manufacturing an electrode according to claim 11 ,
wherein the high-permeability portion, the low-permeability portion and the transition portion are formed such that the insulation resistivity of the high-permeability portion is low, the insulation resistivity of the low-permeability portion is high, and the insulation resistivity of the transition portion increases from the high-permeability portion side toward the low-permeability portion side.

14 . The method of manufacturing an electrode according to claim 11 ,
wherein the high-permeability portion, the low-permeability portion and the transition portion are formed such that the density of the high-permeability portion is low, the density of the low-permeability portion is high, and the density of the transition portion increases from the high-permeability portion side toward the low-permeability portion side.

15 . The method of manufacturing an electrode according to claim 11 , wherein:
the active material layer is formed intermittently along the longitudinal direction of the current collector; the resin layer is formed on the active material layer, and is formed to protrude onto the non-coated portion on one end portion side in the longitudinal direction of the active material layer, and onto the non-coated portion of the other end portion side of the active material; and the method comprises a step of cutting the electrode in a predetermined shape such that the electrode comprises the non-coated portion on which resin layer is not formed on one end portion side in the longitudinal direction.

16 . The method of manufacturing an electrode according to claim 1 , further comprising a step of filling voids of the resin and insulating material of the low-permeability portion by compressing the resin layer, melting the resin of the resin layer, or spraying resin.

17 . A method of manufacturing an electrochemical device comprising steps of:
forming positive electrodes, negative electrodes or both positive electrodes and negative electrodes by the method of manufacturing an electrode according to claim 1 ; forming a multilayered electrode body by alternately laminating the positive electrodes and the negative electrodes with separators interposed therebetween; and accommodating the multilayered electrode body and an electrolyte inside an external container.

Assignees

• Envision Aesc Energy Devices Ltd

Inventors

• Hirai Masanori
• Mimura Kazuya

Classifications

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M4/06

  Electrodes for primary cells · CPC title

• H01M4/621

  Binders · CPC title

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M4/366 Primary

  as layered products · CPC title