Wound electrochemical device

Patent metadata

Field	Value
Publication number	US-9048030-B2
Application number	US-201213591597-A
Country	US
Kind code	B2
Filing date	Aug 22, 2012
Priority date	Aug 29, 2011
Publication date	Jun 2, 2015
Grant date	Jun 2, 2015

Abstract

In an area where positive and negative electrode leads 11, 21 oppose each other through a separator 30 in a wound electrochemical device 1 , active material layers are removed from surfaces of current collectors 10 a, 20 a , so as to form open areas 10 e, 20 e . Even if the active material layers are formed on the surfaces of the current collectors, surfaces opposing them through the separator are provided with the leads protected by insulating tapes, whereby the areas serving as the open areas originally have no function as a capacitor. Therefore, by removing the active material layers from areas having no function as a capacitor, the wound electrochemical device 1 can be made further thinner while inhibiting the capacity as a device from lowering.

First claim

What is claimed is:

1. A wound electrochemical device comprising:
a band-shaped first electrode;
a band-shaped second electrode; and
a band-shaped separator, the first and second electrodes being wound and overlaid such as to hold the separator therebetween;
the band-shaped first electrode having:
a first current collector having a length, a width, and a thickness, wherein:
the length of the first current collector is in a direction of winding of the first current collector;
the width of the first current collector is in a direction parallel to a winding axis of the wound electrochemical device, and orthogonal to the length direction of the first current collector; and
the thickness of the first current collector is in a direction that is within a plane that is perpendicular to the winding axis of the wound electrochemical device, and orthogonal to the length and width directions of the first current collector;

a first active material layer on at least a portion of each of two opposing major sides of the first current collector that are defined by the length and width directions of the first current collector, and
a first lead connected to a first exposed part of the first current collector that is free of the first active material layer, a width of the first lead at an area that the first lead is connected to the first current collector being in a direction substantially parallel to the length direction of the first current collector at the area that the first lead is connected to the first current collector;

the band-shaped second electrode having:
a second current collector having a length, a width, and a thickness, wherein:
the length of the second current collector is in a direction of winding of the second current collector;
the width of the second current collector is in a direction parallel to a winding axis of the wound electrochemical device, and orthogonal to the length direction of the second current collector; and
the thickness of the second current collector is in a direction that is within a plane that is perpendicular to the winding axis of the wound electrochemical device, and orthogonal to the length and width directions of the second current collector;

a second active material layer on at least a portion of each of two opposing major sides of the second current collector that are defined by the length and width directions of the second current collector, and
a second lead connected to a second exposed part of the second current collector free of the second active material layer, a width of the second lead at an area that the second lead is connected to the second current collector being in a direction substantially parallel to the length direction of the second current collector at the area that the second lead is connected to the second current collector;

wherein:
the first lead and the second lead abut against opposing surfaces of the separator through respective protective tapes;
the first exposed part has:
a length direction parallel to the length direction of the first current collector at the first exposed part;
opposing first and second ends in the length direction of the first exposed part, the first and second ends of the first exposed part abutting respective portions of the first active material layer;
a first connection area connected to the first lead;
a first open area adjacent to the first connection area in the length direction of the first exposed part, a length of the first open area as measured in the length direction of the first exposed part is greater than the width of the second lead;

the second exposed part has:
a length direction parallel to the length direction of the second current collector at the second exposed part;
opposing first and second ends in the length direction of second exposed part, the first and second ends of the second exposed part abutting respective portions of the second active material layer;
a second connection area connected to the second lead;
a second open area adjacent to the second connection area in the length direction of the second exposed part, a length of the second open area as measured in the length direction of the second exposed part area is greater than the width of the first lead;

the first and second exposed parts oppose each other through the separator;
the first lead opposes the second open area of the second exposed part through the separator;
the second lead opposes the first open area of the first exposed part through the separator;
the first and second leads are adjacent to each other in respect to the length direction of the first current collector, and are positioned between an outermost winding of the first current collector and an outermost winding of the second current collector;
a current collector is not interposed between the first and second leads; and
the number of separator layers interposed between the first and second leads is one.

2. The wound electrochemical device according to claim 1 , wherein:
the first and second exposed parts delimit an area that intervenes between the first and second exposed parts, the intervening area having:
a longitudinal direction that is substantially parallel to the length direction of the first and second exposed parts, and
a height direction that is substantially perpendicular to the longitudinal direction of the intervening area and substantially parallel to the thickness direction of the first and second current collectors at the first and second exposed parts;

a portion of the first lead and a portion of the second lead are contained within the intervening area, arranged adjacent to each other in the longitudinal direction of the intervening area; and
only one or more selected from the group consisting of:
a single separator layer,
the first lead portion or the second lead portion, and
one of the respective protective tapes,

intervene in the height direction of the intervening area between the first and second exposed parts throughout the longitudinal direction of the intervening area.

Assignees

• Hasegawa Hiroaki
• Hinoki Kiyonori
• Tdk Corp

Inventors

• Hasegawa Hiroaki
• Hinoki Kiyonori

Classifications

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01M10/0587

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

• Y02E60/122

  Cross-Sectional Technologies · mapped topic

• H01G11/76

  specially adapted for integration in multiple or stacked hybrid or EDL capacitors · CPC title

• H01M10/0431

  Cells with wound or folded electrodes (H01M10/045 takes precedence) · CPC title