JP2017163126A - Electrochemical device and method of manufacturing electrochemical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrochemical device that supports capacitance increase and cost reduction, as well as a method of manufacturing such an electrochemical device.SOLUTION: An electrochemical device according to the present invention includes a positive electrode terminal, a negative electrode terminal, a first electrode body, a second electrode body, and an electrolytic solution. The positive electrode terminal is flat plate-shaped, and has a first principal face and a second principal face on the opposite side. The negative electrode terminal is flat plate-shaped, and has a third principal face and a fourth principal face on the opposite side. The first electrode body has a first wound positive-electrode non-forming region and a first wound negative-electrode non-forming region. The second electrode body has a second wound positive-electrode non-forming region and a second wound negative-electrode non-forming region. The first wound positive-electrode non-forming region, the first wound negative-electrode non-forming region, the second wound positive-electrode non-forming region, and the second wound negative-electrode non-forming region are joined to the first principal face, the third principal face, the second principal face, and the fourth principal face, respectively.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electrochemical device having an electrode body formed by winding a positive electrode, a negative electrode, and a separator, and a method for manufacturing the electrochemical device.

  New electrochemical devices such as lithium ion capacitors are being used, but cost reduction is required for further market creation. For this purpose, an electrochemical device having a structure with low member cost and excellent productivity is desirable. In addition, miniaturization and high capacity are demanded as the characteristics of electrochemical devices.

  As a structure of the electrochemical device, there is a structure in which a positive electrode and a negative electrode are stacked via a separator and an electrode body having a flat wound structure wound in a flat shape is loaded in an outer can together with an electrolytic solution. The positive electrode and the negative electrode need to be joined to the positive electrode terminal and the negative electrode terminal provided on the outer can, respectively.

  For example, Patent Document 1 discloses a secondary battery including an electrode body having a flat wound structure and a positive electrode terminal and a negative electrode terminal respectively connected to both ends of a winding center axis of the electrode body. In Patent Document 2, an ultrasonic horn is sandwiched between two electrode bodies, two current collecting terminals are arranged outside the electrode body, the current collecting terminals are sandwiched between ultrasonic anvils, and the ultrasonic waves are collected on the electrode body by ultrasonic waves. An ultrasonic bonding method for bonding electrical terminals is disclosed.

JP 2014-22179 A JP2012-152810A

  However, in the structures as described in Patent Documents 1 and 2, it is necessary to join two terminals of a positive electrode terminal and a negative electrode terminal to one electrode body. In order to increase the capacity of an electrochemical device, two electrode bodies are often mounted on one electrochemical device. In this case, it is necessary to join four terminals to the electrode body, and the number of parts and the joining process are required. Reduction is required.

  In view of the circumstances as described above, an object of the present invention is to provide an electrochemical device and a method for manufacturing the electrochemical device that can achieve high capacity and low cost.

In order to achieve the above object, an electrochemical device according to an embodiment of the present invention includes a positive electrode terminal, a negative electrode terminal, a first electrode body, a second electrode body, and an electrolytic solution.
The positive electrode terminal has a flat plate shape and has a first main surface and a second main surface opposite to the first main surface.
The negative electrode terminal has a flat plate shape, and has a third main surface and a fourth main surface opposite to the third main surface.
The first electrode body includes a first positive electrode current collector that is a metal foil, and a first positive electrode active material layer formed on the first positive electrode current collector. A first positive electrode forming region in which the first positive electrode active material layer is formed on the positive electrode current collector, and a first in which the first positive electrode active material layer is not formed on the first positive electrode current collector. A first positive electrode provided with a positive electrode unformed region, a first negative electrode current collector that is a metal foil, and a first negative electrode active material layer formed on the first negative electrode current collector And a first negative electrode forming region in which the first negative electrode active material layer is formed on the first negative electrode current collector and the first negative electrode active material layer on the first negative electrode current collector. A first negative electrode provided with a first negative electrode non-formation region, and a first separator separating the first positive electrode and the first negative electrode, the first positive electrode, A first electrode body in which the first negative electrode and the first separator are stacked and wound, and the first positive electrode unformed region is a wound portion. A region winding portion and a first negative electrode unformed region winding portion, which is a portion where the first negative electrode unformed region is wound, are provided.
The second electrode body includes a second positive electrode current collector that is a metal foil, and a second positive electrode active material layer formed on the second positive electrode current collector. A second positive electrode forming region in which the second positive electrode active material layer is formed on the positive electrode current collector and a second in which the second positive electrode active material layer is not formed on the second positive electrode current collector. A second positive electrode provided with a positive electrode non-forming region, a second negative electrode current collector that is a metal foil, and a second negative electrode active material layer formed on the second negative electrode current collector And a second negative electrode forming region in which the second negative electrode active material layer is formed on the second negative electrode current collector and the second negative electrode active material layer on the second negative electrode current collector. A second negative electrode provided with a second negative electrode non-formed region, and a second separator separating the second positive electrode and the second negative electrode, the second positive electrode, A second electrode body in which the second negative electrode and the second separator are stacked and wound, and the second positive electrode unformed region is a wound portion of the second positive electrode unformed A region winding portion and a second negative electrode unformed region winding portion, which is a portion where the second negative electrode unformed region is wound, are provided.
The electrolytic solution immerses the first electrode body and the second electrode body.
The first positive electrode unformed region wound portion is bonded to the first main surface, the first negative electrode unformed region wound portion is bonded to the third main surface, and the second positive electrode uncovered region is not bonded. The formation region winding portion is bonded to the second main surface, and the second negative electrode unformed region winding portion is bonded to the fourth main surface.

  According to this configuration, the electrochemical device includes the two electrode bodies, the first electrode body and the second electrode body, and the capacity of the electrochemical device can be increased. Further, the positive electrode terminal and the negative electrode terminal can be formed in a flat plate shape, and the cost of parts can be reduced by simplifying the structure.

The first electrode body has a flat wound structure in which the first winding body in which the first positive electrode, the first negative electrode, and the first separator are wound is flattened into a plate shape. And
The second electrode body has a flat wound structure in which a second winding body in which the second positive electrode, the second negative electrode, and the second separator are wound is flattened into a plate shape. May be.

The first electrode body further includes two lithium ion supply sources bonded to the front surface and the back surface of the first wound body,
The second electrode body may further include two lithium ion supply sources joined to the front surface and the back surface of the second winding body, respectively.

  By separately arranging lithium ion supply sources on both the front and back sides of the wound body having a flat wound structure, the vertical doping efficiency of lithium ions can be improved, and a structure with excellent productivity can be obtained. .

In order to achieve the above object, in the method for producing an electrochemical device according to one aspect of the present invention, the electrochemical device has a flat plate shape and has a first main surface and a second main surface opposite to the first main surface. A positive electrode terminal; a negative electrode terminal that is flat and has a third main surface and a fourth main surface opposite to the third main surface; a first positive electrode current collector that is a metal foil; and A first positive electrode active material layer formed on the first positive electrode current collector, and the first positive electrode active material layer formed on the first positive electrode current collector A first positive electrode in which a first positive electrode non-formation region in which the first positive electrode active material layer is not formed on the formation region and the first positive electrode current collector is provided; and a first metal foil A negative electrode current collector; and a first negative electrode active material layer formed on the first negative electrode current collector, wherein the first negative electrode active material layer is formed on the first negative electrode current collector. Formed The first negative electrode forming region, the first negative electrode in which the first negative electrode active material layer is not formed on the first negative electrode current collector, and the first negative electrode non-formation region is provided. A first electrode body including a first positive electrode, a first separator, and a first separator separating the first negative electrode, wherein the first positive electrode, the first negative electrode, and the first separator are laminated and wound. The first positive electrode non-formed region wound portion is a portion where the first positive electrode unformed region is wound, and the first negative electrode unformed region is a portion where the first negative electrode unformed region is wound. A first electrode body including a negative electrode unformed region winding portion, a second positive electrode current collector that is a metal foil, and a second positive electrode active material formed on the second positive electrode current collector A second positive electrode forming region in which the second positive electrode active material layer is formed on the second positive electrode current collector and the second positive electrode current collector A second positive electrode in which a second positive electrode non-formation region where the second positive electrode active material layer is not formed is provided, a second negative electrode current collector that is a metal foil, and the second negative electrode current collector. A second negative electrode active material layer formed on the electric current body, and a second negative electrode forming region in which the second negative electrode active material layer is formed on the second negative electrode current collector and the second negative electrode active region. A second negative electrode in which a second negative electrode non-formation region in which the second negative electrode active material layer is not formed is provided on the second negative electrode current collector, the second positive electrode, and the second negative electrode. A second electrode body, wherein the second positive electrode, the second negative electrode, and the second separator are laminated and wound, and the second positive electrode is not A second positive electrode non-formed region wound portion, which is a portion where the formation region is wound, and a second negative portion, which is a portion where the second negative electrode non-formed region is wound. A second electrode body including a pole-unformed region winding part is prepared.
The first positive electrode unformed region wound portion is bonded to the first main surface, and the second positive electrode unformed region wound portion is bonded to the second main surface.
The first negative electrode unformed region wound portion is bonded to the third main surface, and the second negative electrode unformed region wound portion is bonded to the fourth main surface.

  According to this manufacturing method, the first positive electrode unformed region wound portion and the second positive electrode unformed region wound portion are simultaneously bonded to both the front and back surfaces of the positive electrode terminal, It is possible to simultaneously bond the second negative electrode unformed region wound portion to both the front and back surfaces of the negative electrode terminal. The first positive electrode unformed region wound portion and the second positive electrode unformed region wound portion are respectively joined to the positive electrode terminal, and the first negative electrode unformed region wound portion and the second negative electrode unformed region wound portion are joined. Since it is not necessary to join each to the negative electrode terminal, the manufacturing process can be simplified and the manufacturing cost can be reduced.

  Joining the first positive electrode unformed region winding part to the first main surface, joining the second positive electrode non-formed region winding part to the second main surface, and the first In the step of bonding the negative electrode non-formed region wound portion to the third main surface and bonding the second negative electrode non-formed region wound portion to the fourth main surface, bonding is performed by ultrasonic bonding. Also good.

In the step of joining the first positive electrode unformed region winding part to the first main surface and joining the second positive electrode non-formed region winding part to the second main surface, Sandwiching the positive electrode non-formed region wound part and the second positive electrode non-formed region wound part with an ultrasonic bonding instrument to join the first positive electrode non-formed region wound part to the first main surface; Bonding the second positive electrode unformed region wound portion to the second main surface;
In the step of bonding the first negative electrode unformed region wound portion to the third main surface and bonding the second negative electrode unformed region wound portion to the fourth main surface, The negative electrode non-formed region winding part and the second negative electrode non-formed region wound part are sandwiched by an ultrasonic bonding instrument to join the first negative electrode non-formed region wound part to the third main surface, The second negative electrode unformed region wound portion may be bonded to the fourth main surface.

  According to this configuration, the first positive electrode non-formed region wound part and the second positive electrode non-formed region wound part are sandwiched between the first positive electrode non-formed region wound part and the first positive electrode non-formed region wound part and the second 2 positive electrode non-formation area winding parts are simultaneously joined to both front and back surfaces of the positive electrode terminal, and the first negative electrode non-formation area winding part and the second negative electrode non-formation area winding part are sandwiched by an ultrasonic bonding instrument. Therefore, the first negative electrode non-formed region wound portion and the second negative electrode non-formed region wound portion can be simultaneously bonded to the front and back surfaces of the negative electrode terminal.

In order to achieve the above object, an electrochemical device according to an embodiment of the present invention includes a positive electrode terminal, a negative electrode terminal, a first electrode body, a second electrode body, and an electrolytic solution.
The positive electrode terminal is plate-shaped and has a first main surface and a second main surface opposite to the first main surface.
The negative electrode terminal is plate-shaped and has a third main surface and a fourth main surface opposite to the third main surface.
The first electrode body includes a first positive electrode current collector that is a metal foil, and a first positive electrode active material layer formed on the first positive electrode current collector. A first positive electrode forming region in which the first positive electrode active material layer is formed on the positive electrode current collector, and a first in which the first positive electrode active material layer is not formed on the first positive electrode current collector. A first positive electrode provided with a positive electrode unformed region, a first negative electrode current collector that is a metal foil, and a first negative electrode active material layer formed on the first negative electrode current collector And a first negative electrode forming region in which the first negative electrode active material layer is formed on the first negative electrode current collector and the first negative electrode active material layer on the first negative electrode current collector. A first negative electrode provided with a first negative electrode non-formation region, and a first separator separating the first positive electrode and the first negative electrode, the first positive electrode, A first electrode body in which the first negative electrode and the first separator are stacked and wound, and the first positive electrode unformed region is a wound portion. A region winding portion and a first negative electrode unformed region winding portion, which is a portion where the first negative electrode unformed region is wound, are provided.
The second electrode body includes a second positive electrode current collector that is a metal foil, and a second positive electrode active material layer formed on the second positive electrode current collector. A second positive electrode forming region in which the second positive electrode active material layer is formed on the positive electrode current collector and a second in which the second positive electrode active material layer is not formed on the second positive electrode current collector. A second positive electrode provided with a positive electrode non-forming region, a second negative electrode current collector that is a metal foil, and a second negative electrode active material layer formed on the second negative electrode current collector And a second negative electrode forming region in which the second negative electrode active material layer is formed on the second negative electrode current collector and the second negative electrode active material layer on the second negative electrode current collector. A second negative electrode provided with a second negative electrode non-formed region, and a second separator separating the second positive electrode and the second negative electrode, the second positive electrode, A second electrode body in which the second negative electrode and the second separator are stacked and wound, and the second positive electrode unformed region is a wound portion of the second positive electrode unformed A region winding portion and a second negative electrode unformed region winding portion, which is a portion where the second negative electrode unformed region is wound, are provided.
The electrolytic solution immerses the first electrode body and the second electrode body.
The first positive electrode unformed region wound portion is bonded to the first main surface, the first negative electrode unformed region wound portion is bonded to the third main surface, and the second positive electrode uncovered region is not bonded. The formation region winding portion is bonded to the second main surface, and the second negative electrode unformed region winding portion is bonded to the fourth main surface.

  In the positive electrode terminal, the first positive electrode non-formed region wound portion and the second positive electrode non-formed region wound portion are joined, and an electrode body joined portion having a first width and a first thickness, A first electrode body, the second electrode body, and an external terminal portion having a second width and a second thickness protruding outside the housing space for housing the electrolytic solution, the electrode body joint portion, and the external body A terminal portion, and a relay portion having a third width and a third thickness, wherein the first width is larger than the third width, and the second width is the first width. The first thickness may be greater than the second thickness, and the third thickness may be greater than the first thickness.

According to this configuration, while satisfying the requirements required for each part of the positive electrode terminal, the difference in cross-sectional area of each part can be reduced, and the difference in electrical resistance between the parts can be reduced.

  In the negative electrode terminal, the first negative electrode non-formed region wound portion and the second negative electrode non-formed region wound portion are joined, and an electrode assembly joined portion having a first width and a first thickness, A first electrode body, the second electrode body, and an external terminal portion having a second width and a second thickness protruding outside the housing space for housing the electrolytic solution, the electrode body joint portion, and the external body A terminal portion, and a relay portion having a third width and a third thickness, wherein the first width is larger than the third width, and the second width is the first width. The first thickness may be greater than the second thickness, and the third thickness may be greater than the first thickness.

  According to this configuration, while satisfying the requirements required for each part of the negative electrode terminal, the difference in the cross-sectional area of each part can be reduced, and the difference in electrical resistance between the parts can be reduced.

  In the positive electrode terminal, the first positive electrode non-formed region wound portion and the second positive electrode non-formed region wound portion are joined, and an electrode body joined portion having a first width and a first thickness, A first electrode body, the second electrode body, and an external terminal portion having a second width and a second thickness protruding outside the housing space for housing the electrolytic solution, the electrode body joint portion, and the external body A terminal portion, and a relay portion having a third width and a third thickness, wherein the first width is larger than the third width, and the second width is the first width. The first thickness is greater than the second thickness, the third thickness is greater than the first thickness, and the negative electrode terminal includes the first negative electrode unformed region winding portion and the first thickness. Two negative electrode unformed region winding portions are joined, an electrode body joint portion having a fourth width and a fourth thickness, the first electrode body, Projecting outside the housing space for housing the electrode body and the electrolyte solution, and connecting the external terminal portion having the fifth width and the fifth thickness to the electrode body joint portion and the external terminal portion, 6 and a relay portion having a sixth thickness, wherein the fourth width is greater than the sixth width, the fifth width is greater than the fourth width, and the fourth thickness. May be larger than the fifth thickness, and the sixth thickness may be larger than the fourth thickness.

  According to this configuration, while satisfying the requirements required for each part in each of the positive electrode terminal and the negative electrode terminal, the difference in cross-sectional area of each part can be reduced, and the difference in electrical resistance between the parts can be reduced. .

  In the positive electrode terminal, the electrode body joint portion, the external terminal portion, and the relay portion may have the same cross-sectional area.

  In the negative electrode terminal, the cross-sectional areas of the electrode body joint portion, the external terminal portion, and the relay portion may be the same.

  As described above, according to the present invention, it is possible to provide an electrochemical device and an electrochemical device manufacturing method capable of increasing the capacity and reducing the cost.

1 is a perspective view of an electrochemical device according to a first embodiment of the present invention. It is a disassembled perspective view of the same electrochemical device. It is a disassembled perspective view of the same electrochemical device. It is a perspective view of the electrode body with which the same electrochemical device is provided. It is sectional drawing of the electrode body with which the same electrochemical device is provided. It is sectional drawing of the electrode body with which the same electrochemical device is provided. It is a top view of the positive electrode of the electrode body with which the same electrochemical device is provided. It is sectional drawing of the positive electrode of the electrode body with which the same electrochemical device is provided. It is a top view of the negative electrode of the electrode body with which the same electrochemical device is provided. It is a top view of the negative electrode of the electrode body with which the same electrochemical device is provided. It is a top view of the positive electrode and negative electrode of an electrode body with which the electrochemical device is provided. It is sectional drawing of the positive electrode and negative electrode of an electrode body with which the same electrochemical device is provided. It is a schematic diagram which shows the lithium ion supply source of the electrode body with which the same electrochemical device is provided. It is a perspective view of the positive electrode terminal and negative electrode terminal with which the same electrochemical device is equipped. It is a perspective view of the positive electrode terminal and negative electrode terminal with which the same electrochemical device is equipped. It is a top view of the 1st electrode body with which the same electrochemical device is provided, a positive electrode terminal, and a negative electrode terminal. It is a top view of the 2nd electrode body with which the same electrochemical device is provided, a positive electrode terminal, and a negative electrode terminal. It is sectional drawing of the 1st electrode body with which the same electrochemical device is equipped, a 2nd electrode body, and a positive electrode terminal. It is sectional drawing of the 1st electrode body with which the same electrochemical device is equipped, a 2nd electrode body, and a negative electrode terminal. It is a schematic diagram of the electrochemical device which concerns on a comparative example. It is a schematic diagram of the electrochemical device which concerns on a comparative example. It is a schematic diagram of the electrochemical device which concerns on a comparative example. It is a schematic diagram which shows the manufacturing method of the electrochemical device which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the manufacturing method of the electrochemical device. It is a schematic diagram which shows the manufacturing method of the electrochemical device. It is a schematic diagram which shows the manufacturing method of the electrochemical device. It is a perspective view of a partial structure of an electrochemical device according to a second embodiment of the present invention. It is a top view of the positive electrode terminal with which the same electrochemical device is provided. It is a perspective view of the positive electrode terminal with which the same electrochemical device is provided. It is a perspective view of the positive electrode terminal with which the same electrochemical device is provided. It is a schematic diagram which shows the width | variety of each part of the positive electrode terminal with which the same electrochemical device is equipped. It is a schematic diagram which shows the thickness of each part of the positive electrode terminal with which the same electrochemical device is equipped. It is a top view of the negative electrode terminal with which the same electrochemical device is equipped. It is a perspective view of the negative electrode terminal with which the same electrochemical device is provided. It is a perspective view of the negative electrode terminal with which the same electrochemical device is provided. It is a schematic diagram which shows the width | variety of each part of the negative electrode terminal with which the same electrochemical device is equipped. It is a schematic diagram which shows the thickness of each part of the negative electrode terminal with which the same electrochemical device is equipped. It is a schematic diagram of the rolling deformed strip used as the material of the positive electrode terminal and negative electrode terminal with which the same electrochemical device is provided. It is a schematic diagram which shows the manufacturing method of the positive electrode terminal and negative electrode terminal with which the same electrochemical device is equipped.

(First embodiment)
A first embodiment of the present invention will be described.

[Structure of electrochemical device]
FIG. 1 is a perspective view of an electrochemical device 100 according to the first embodiment, and FIGS. 2 and 3 are exploded perspective views of the electrochemical device 100.

  The electrochemical device 100 can be a lithium ion capacitor. The electrochemical device 100 may be another type of capacitor such as an electric double layer capacitor, or may be a battery such as a lithium ion battery or a nickel metal hydride battery. In addition, the electrochemical device 100 can be any kind of electrochemical device that can be realized by the following structure. In the following description, it is assumed that the electrochemical device 100 is a lithium ion capacitor.

  2 and 3, the electrochemical device 100 includes a first electrode body 101, a second electrode body 102, a positive electrode terminal 103, a negative electrode terminal 104, a positive electrode terminal plate 105, a negative electrode terminal plate 106, an insulating film 107, An outer can 108 and a lid member 109 are provided.

  As shown in FIGS. 2 and 3, the positive electrode terminal 103 and the negative electrode terminal 104 are attached to a lid member 109, and the first electrode body 101 and the second electrode body 102 are both joined to the positive electrode terminal 103 and the negative electrode terminal 104. ing. The ends of the first electrode body 101 and the second electrode body 102 are covered with an insulating film 107 and are accommodated in an outer can 108.

  As shown in FIG. 1, the outer can 108 and the lid member 109 are joined to form the electrochemical device 100. A space formed by the outer can 108 and the lid member 109 (hereinafter referred to as an accommodation space) is filled with an electrolytic solution, and the first electrode body 101 and the second electrode body 102 are immersed in the electrolytic solution.

  The first electrode body 101 and the second electrode body 102 have the same structure. FIG. 4 is a perspective view of an electrode body 120 used as the first electrode body 101 and the second electrode body 102. As shown in the figure, the electrode body 120 includes an electrode region winding part 121, a positive electrode non-formation region winding part 122, and a negative electrode non-formation region winding part 123.

  5 is a cross-sectional view of the electrode body 120, and is a cross-sectional view taken along the line AA of FIG. 6 is a cross-sectional view of the electrode body 120, which is a cross-sectional view taken along line BB in FIG. As shown in these drawings, the electrode body 120 includes a positive electrode 130, a negative electrode 140, a separator 150, and a lithium ion supply source 160. Note that the number of layers of the positive electrode 130, the negative electrode 140, and the separator 150 shown in FIGS. 5 and 6 is a schematic one and is actually larger. For example, the positive electrode 130 can have 21 layers and the negative electrode 140 can have 23 layers.

  FIG. 7 is a plan view of the positive electrode 130 before winding. FIG. 8 is a cross-sectional view of the positive electrode 130, and is a cross-sectional view taken along line CC in FIG. As shown in the figure, the positive electrode 130 includes a positive electrode current collector 131 and a positive electrode active material layer 132.

  The positive electrode current collector 131 is a metal foil, and is made of, for example, aluminum. The positive electrode current collector 131 is provided with pores through which ions can pass, and can be a foil having pores formed by electrolytic etching or the like. The thickness of the positive electrode current collector 131 is, for example, 0.02 mm.

  The positive electrode active material layer 132 may be a mixture of a positive electrode active material and a binder resin, and may further include a conductive additive. The positive electrode active material is a material that can adsorb lithium ions and anions in the electrolytic solution, such as activated carbon or polyacene carbide.

  The binder resin is a synthetic resin that joins the positive electrode active material. For example, styrene butadiene rubber, polyethylene, polypropylene, polyethylene terephthalate, aromatic polyamide, carboxymethyl cellulose, fluorine rubber, polyvinylidene fluoride, isoprene rubber, butadiene rubber, and ethylene. Propylene rubber or the like may be used.

  The conductive auxiliary agent is a particle made of a conductive material, and improves the conductivity between the positive electrode active materials. Examples of the conductive assistant include carbon materials such as graphite and carbon black. These may be single and multiple types may be mixed. The conductive auxiliary agent may be a metal material or a conductive polymer as long as it is a conductive material.

  As shown in FIG. 8, the positive electrode active material layer 132 is formed on both the front and back surfaces of the positive electrode current collector 131. Here, the positive electrode active material layer 132 is not formed on the entire surface of the positive electrode current collector 131, and a region where the positive electrode active material layer 132 is not formed is provided in a part of the positive electrode current collector 131.

  Hereinafter, in the positive electrode 130, a region where the positive electrode active material layer 132 is provided on the positive electrode current collector 131 is referred to as a positive electrode formation region 130a, and the positive electrode active material layer 132 is not provided and the positive electrode current collector 131 is exposed. The region is defined as a positive electrode unformed region 130b. As shown in FIG. 7, the positive electrode non-forming region 130 b is provided in a strip shape along one side of the positive electrode 130.

  FIG. 9 is a plan view of the negative electrode 140 before winding. 10 is a cross-sectional view of the negative electrode 140, and is a cross-sectional view taken along the line DD of FIG. As shown in the figure, the negative electrode 140 includes a negative electrode current collector 141 and a negative electrode active material layer 142.

  The negative electrode current collector 141 is a metal foil, and is made of, for example, copper. The negative electrode current collector 141 is provided with pores through which ions can pass, and a foil having pores formed by electrolytic etching or the like can be obtained. The thickness of the negative electrode current collector 141 is, for example, 0.01 mm.

  The negative electrode active material layer 142 may be a mixture of a negative electrode active material and a binder resin, and may further include a conductive additive. As the negative electrode active material, a material that can occlude lithium ions in the electrolytic solution, for example, a carbon-based material such as non-graphitizable carbon (hard carbon), graphite, or soft carbon can be used.

  The binder resin is a synthetic resin that joins the negative electrode active material. For example, styrene butadiene rubber, polyethylene, polypropylene, polyethylene terephthalate, aromatic polyamide, carboxymethyl cellulose, fluorine rubber, polyvinylidene fluoride, isoprene rubber, butadiene rubber, and ethylene. Propylene rubber or the like may be used.

  The conductive auxiliary agent is a particle made of a conductive material, and improves the conductivity between the negative electrode active materials. Examples of the conductive assistant include carbon materials such as graphite and carbon black. These may be single and multiple types may be mixed. The conductive auxiliary agent may be a metal material or a conductive polymer as long as it is a conductive material.

  As shown in FIG. 10, the negative electrode active material layer 142 is formed on both the front and back surfaces of the negative electrode current collector 141. Here, the negative electrode active material layer 142 is not formed on the entire surface of the negative electrode current collector 141, and a region where the negative electrode active material layer 142 is not formed is provided in a part of the negative electrode current collector 141.

  Hereinafter, in the negative electrode 140, a region where the negative electrode active material layer 142 is provided on the negative electrode current collector 141 is referred to as a negative electrode formation region 140a, and the negative electrode active material layer 142 is not provided and the negative electrode current collector 141 is exposed. The region is a negative electrode non-formed region 140b. As shown in FIG. 9, the negative electrode non-formation region 140 b is provided in a strip shape along one side of the negative electrode 140.

  Separator 150 separates positive electrode 130 and negative electrode 140 and transmits ions contained in an electrolyte solution described later. The separator 150 can be a woven fabric, a non-woven fabric, a synthetic resin microporous film, or the like. For example, the separator 150 can be made of a polyethylene resin as a main material.

  The electrode body 120 is configured by stacking and winding a positive electrode 130, a negative electrode 140, and a separator 150. FIG. 11 is a plan view of a laminate in which these are laminated. 12 is a cross-sectional view of the same laminate, and is a cross-sectional view taken along line EE of FIG. In addition, illustration of the separator 150 is abbreviate | omitted in FIG.

  As illustrated in FIG. 12, the positive electrode 130, the negative electrode 140, and the separator 150 are stacked so that the separator 150 is positioned between the positive electrode 130 and the negative electrode 140. Here, as shown in FIG. 11, the positive electrode 130 and the negative electrode 140 are arranged so that the positive electrode formation region 130a and the negative electrode formation region 140a face each other and the positive electrode non-formation region 130b and the negative electrode non-formation region 140b do not face each other. . The separator 150 is disposed so as to separate the positive electrode forming region 130a and the negative electrode forming region 140a.

  The laminated body 170 is wound and flattened to form a wound body 170. FIG. 13 is a cross-sectional view of the wound body 170. The size of the wound body 170 can be, for example, a length of 115 mm, a width of 67 mm, and a thickness of 5.5 mm.

  As shown in FIG. 5, the electrode body 120 includes two lithium ion supply sources 160. The lithium ion supply source 160 is obtained by attaching lithium metal to the outer surface of a metal foil such as a copper foil, and is attached so that the lithium metal faces the negative electrode 140. One lithium ion supply source 160 is affixed to both the front and back surfaces of the wound body 170 shown in FIG. A part of the wound body 170 and the lithium ion supply source 160 are covered with a separator 150.

  The electrode body 120 has the above configuration. The electrode region winding portion 121 is a portion of the electrode body 120 where the positive electrode forming region 130a, the negative electrode forming region 140a, and the separator 150 are wound. The positive electrode unformed region wound portion 122 is a portion of the electrode body 120 where the positive electrode unformed region 130b is wound, that is, a portion where only the positive electrode current collector 131 is wound. The negative electrode unformed region winding portion 123 is a portion of the first electrode body 101 where the negative electrode non-formed region 140b is wound, that is, a portion where only the negative electrode current collector 141 is wound.

  Each of the first electrode body 101 and the second electrode body 102 has the configuration of the electrode body 120. Therefore, as shown in FIG. 3, the first electrode body 101 and the second electrode body 102 each include an electrode region winding part 121, a positive electrode non-formation area winding part 122, and a negative electrode non-formation area winding part 123.

  The positive terminal 103 and the negative terminal 104 are attached to the lid member 109. 14 and 15 are perspective views of the positive electrode terminal 103 and the negative electrode terminal 104. FIG.

  The positive electrode terminal 103 is a plate-like member made of metal. The positive electrode terminal 103 can be made of, for example, aluminum (A1050-H24). The thickness of the positive electrode terminal 103 is 1.5 mm, for example. As shown in FIG. 3, the positive terminal 103 is inserted into the lid member 109 and insulated from the lid member 109 by a terminal support member 110 made of synthetic resin or the like. Thereby, a part of positive electrode terminal 103 is accommodated in the accommodation space, and a part protrudes outside the accommodation space.

  As shown in FIGS. 14 and 15, one of the main surfaces of the positive electrode terminal 103 is a first main surface 103a, and the opposite main surface is a second main surface 103b. The positive electrode terminal 103 is provided with a through-hole 103c that communicates with the first main surface 103a and the second main surface 103b and is used for connection with an external device or the like. The shape of the positive electrode terminal 103 is not particularly limited, and may be a plate shape. For example, the positive electrode terminal 103 may have a shape having a rectangular main surface.

  The negative electrode terminal 104 is a plate-like member made of metal. The negative electrode terminal 104 can be made of, for example, copper (C1100-1 / 4H). The thickness of the negative electrode terminal 104 is, for example, 1.2 mm. As shown in FIG. 3, the negative terminal 104 is inserted into the lid member 109 and insulated from the lid member 109 by a terminal support member 110 made of synthetic resin or the like. Thereby, a part of negative electrode terminal 104 is accommodated in the accommodation space, and a part protrudes outside the accommodation space.

  As shown in FIGS. 14 and 15, one of the main surfaces of the negative electrode terminal 104 is a third main surface 104a, and the opposite main surface is a fourth main surface 104b. The negative electrode terminal 104 is provided with a through hole 104c that communicates with the third main surface 104a and the second main surface 104b and is used for connection to an external device or the like. The shape of the negative electrode terminal 104 is not particularly limited, and may be a plate shape. For example, the negative electrode terminal 104 may have a shape having a rectangular main surface.

  The positive electrode terminal 103 and the negative electrode terminal 104 are arranged such that the first main surface 103a and the third main surface 104a are located on the same plane, and the second main surface 103b and the fourth main surface 104b are located on the same plane. ing.

  The positive terminal plate 105 is a plate-shaped member made of metal. As shown in FIG. 3, the electrochemical device 100 includes two positive terminal plates 105 that are joined to the first electrode body 101 and the second electrode body 102, respectively. The positive terminal plate 105 is made of, for example, aluminum (A1050-H24), and the size thereof is, for example, 40 mm long, 7.5 mm wide, and 0.2 mm thick.

  The negative electrode terminal plate 106 is a plate-shaped member made of metal, and the electrochemical device 100 includes two negative electrode terminal plates 106 joined to the first electrode body 101 and the second electrode body 102 as shown in FIG. Is provided. The negative electrode terminal plate 106 is made of, for example, copper (C1100-1 / 4H), and the size thereof is, for example, 40 mm long, 7.5 mm wide, and 0.2 mm thick.

  As shown in FIG. 3, the first electrode body 101 and the second electrode body 102 face each other via the positive electrode terminal 103 and the negative electrode terminal 104 and are joined to the positive electrode terminal 103 and the negative electrode terminal 104. FIG. 16 is a schematic diagram illustrating a bonding mode of the positive electrode terminal 103 and the negative electrode terminal 104 and the first electrode body 101, and FIG. 17 is a schematic diagram illustrating a bonding mode of the positive electrode terminal 103 and the negative electrode terminal 104 and the second electrode body 102. It is.

  FIG. 18 is a cross-sectional view showing a bonding mode of the positive electrode terminal 103, the first electrode body 101, and the second electrode body 102, and is a cross-sectional view taken along the line FF in FIGS. FIG. 19 is a cross-sectional view showing a joining mode of the negative electrode terminal 104, the first electrode body 101, and the second electrode body 102, and is a cross-sectional view taken along the line GG in FIGS.

  As shown in FIGS. 16 and 18, the positive electrode unformed region winding portion 122 of the first electrode body 101 is bonded to the first main surface 103 a and is sandwiched between the first main surface 103 a and the positive electrode terminal plate 105. Further, the positive electrode unformed region winding portion 122 of the second electrode body 102 is joined to the second main surface 103 b and is sandwiched between the second main surface 103 b and the positive electrode terminal plate 105. In each of the electrode bodies, each positive electrode current collector 131 (see FIG. 6) constituting the positive electrode unformed region winding part 122 is also bonded to each other between the layers.

  As shown in FIGS. 17 and 19, the negative electrode non-formed region winding part 123 of the first electrode body 101 is bonded to the third main surface 104 a and is sandwiched between the third main surface 104 a and the negative electrode terminal plate 106. Further, the negative electrode unformed region winding portion 123 of the second electrode body 102 is joined to the fourth main surface 104 b and is sandwiched between the fourth main surface 104 b and the negative electrode terminal plate 106. In each of the electrode bodies, the respective negative electrode current collectors 141 (see FIG. 6) constituting the negative electrode non-formed region winding part 123 are also bonded to each other between the layers.

  The insulating film 107 (see FIG. 2) is a film made of an insulating material such as a synthetic resin. The electrochemical device 100 includes two insulating films 107. One insulating film 107 covers the first electrode body 101 and the positive electrode unformed region wound portion 122 of the second electrode body 102 and insulates from the outer can 108. The other insulating film 107 covers the negative electrode non-formed region winding portion 123 of the first electrode body 101 and the second electrode body 102 and insulates from the outer can 108.

  The insulating film 107 is made of, for example, a polyimide resin and can have a width of 25 mm. Note that an insulating layer may be provided on the inner peripheral surface of the outer can 108 instead of the insulating film 107.

  The outer can 108 (see FIG. 2) accommodates the first electrode body 101 and the second electrode body 102, and forms an accommodation space together with the lid member 109. The outer can 108 is made of metal, for example, aluminum (A1050-O). The size of the outer can 108 is, for example, a length of 121 mm, a width of 13.5 mm, a thickness of 80 mm, and a plate thickness of, for example, 0.5 mm.

  The lid member 109 (see FIG. 2) is attached to the outer can 108 and supports the positive terminal 103 and the negative terminal 104. The lid member 109 is made of metal, for example, aluminum (A1050-H24). The size of the lid member 109 is, for example, a length of 120 mm, a width of 12.5 mm, and a thickness of 2 mm.

  The lid member 109 has two openings (not shown), and a terminal support member 110 made of an insulating material such as PPS (Polyphenylenesulfide) is attached to the opening. The positive electrode terminal 103 and the negative electrode terminal 104 are inserted into the terminal support member 110 and insulated from the lid member 109.

  The lid member 109 is joined to the outer can 108 by a joining method such as laser welding, and closes the accommodation space. The lid member 109 is provided with a liquid injection port 109 a, and the liquid injection port 109 a is sealed with a liquid injection lid 111. The injection lid 111 is made of a metal such as aluminum (A1050-O), has a disk shape, and has a diameter of 7.6 mm and a thickness of 0.4 mm, for example. The liquid injection lid 111 preferably has a safety valve function for releasing the internal pressure when the internal pressure of the storage space becomes high.

An electrolytic solution is injected into the housing space. The electrolytic solution is a liquid containing lithium ions and anions, and can be, for example, LiPF ₆ EC / MEC (a liquid in which LiPF ₆ is dissolved in a mixed liquid of ethylene carbonate (EC) and methyl ethyl carbonate (MEC)). The injection volume is 80 g, for example.

  The electrochemical device 100 has the above configuration. As described above, the electrochemical device 100 may not be a lithium ion capacitor, and may be other various electrochemical devices. In that case, the types of the positive electrode active material, the negative electrode active material, and the electrolytic solution can be changed according to the type of the electrochemical device. Further, the lithium ion supply source 160 is not necessarily provided.

[Effects of electrochemical devices]
The effect of the electrochemical device 100 will be described after comparison with a comparative example. FIG. 20 is a front view of the electrochemical device 200 according to the comparative example, and is a side view of the electrochemical device 200 of FIG.

  The electrode body 210 includes a positive electrode non-formation region winding part 221 in which a positive electrode current collector foil is wound and a negative electrode non-formation region winding part 222 in which a negative electrode current collector foil is wound. The positive electrode unformed region winding part 221 is joined to the internal positive electrode terminal 211, and the negative electrode non-formed region wound part 222 is joined to the internal negative electrode terminal 212.

  The internal positive terminal 211 is bent in the thickness direction of the electrode body 210 and is connected to the external positive terminal 213. The internal negative terminal 212 is also bent in the thickness direction of the electrode body 210 and is connected to the external negative terminal 214.

  In this structure, since the external terminal and the internal terminal are separate structures for the positive electrode and the negative electrode, the number of parts of the electrochemical device 200 increases, resulting in an increase in cost.

  In order to increase the capacity of electrochemical devices, electrochemical devices including two electrode bodies are also used. FIG. 22 is a perspective view of a partial structure of an electrochemical device 300 according to another comparative example.

  As shown in the figure, the positive electrode unformed region winding portion 312 of the first electrode body 310 and the second electrode body 311 is an internal positive electrode having a shape separated in the thickness direction of the first electrode body 310 and the second electrode body 311. Each of the terminals is joined to the terminal 313 and is sandwiched between the internal positive terminal 313 and the positive terminal plate 314.

  In addition, the negative electrode non-formed region winding portion 315 of the first electrode body 310 and the second electrode body 311 is joined to the internal negative electrode terminal 316 spaced in the thickness direction of the first electrode body 310 and the second electrode body 311, respectively. It is sandwiched between the negative terminal 316 and the negative terminal plate 317.

  In this structure, it is necessary to join the positive electrode unformed region winding portion 312 of both electrode bodies to the internal positive terminal 313 and to join the negative electrode non-formed region winding portion 315 of both electrode bodies to the internal negative terminal 316, respectively. . For this reason, there are many joining processes and productivity is not good. Further, the shapes of the internal positive terminal 313 and the internal negative terminal 316 are complicated, and the cost of these components is high.

  On the other hand, in the electrochemical device 100 according to the present embodiment, the positive electrode terminal 103 and the negative electrode terminal 104 serve as an internal terminal provided inside the outer can 108 and an external terminal provided outside the outer can 108, respectively. The number of parts can be reduced.

  Further, the positive electrode terminal 103 and the negative electrode terminal 104 are flat and have a low component cost. Further, the positive electrode unformed region winding portion 122 of the first electrode body 101 and the second electrode body 102 is collectively bonded to the positive electrode terminal 103 by a joining method described later, and the first electrode body 101 and the second electrode body 102 are joined together. The negative electrode unformed region winding part 123 can be bonded to the negative electrode terminal 104 at a time, and the bonding process can be reduced.

  Therefore, the electrochemical device 100 has a structure that has a large capacity and can be manufactured at low cost.

[Production method]
A method for manufacturing the electrochemical device 100 will be described.

  The electrode body 120 can be manufactured by laminating and winding the positive electrode 130, the negative electrode 140, and the separator 150 as described above, and attaching the lithium ion supply source 160 to both the front and back surfaces as a flat wound structure.

  The two electrode bodies 120 are joined to the positive electrode terminal 103 and the negative electrode terminal 104 as the first electrode body 101 and the second electrode body 102 (see FIG. 3).

  23 and 24 are schematic views showing a method of joining the first electrode body 101 and the second electrode body 102 to the positive electrode terminal 103. FIG. As shown in FIG. 23, the positive electrode terminal 103 is inserted between the positive electrode unformed region winding part 122 of the first electrode body 101 and the second electrode body 102. Further, the positive electrode terminal plate 105 is disposed on the positive electrode non-formed region winding portion 122 of the first electrode body 101 and the second electrode body 102. In this state, the two positive terminal plates 105 are sandwiched and fixed by a clamp or the like.

  Subsequently, as shown in FIG. 24, the two positive electrode terminal plates 105 are sandwiched between the ultrasonic welding anvil 501 and the ultrasonic welding horn 502 (arrows in the figure). The thickness of this portion is, for example, 21 layers of the positive electrode terminal 103 having a thickness of 1.5 mm, 21 positive electrode current collectors 131 having a thickness of 0.02 mm, and two positive electrode terminal plates 105 having a thickness of 0.2 mm. 74 mm.

  By applying an ultrasonic wave in this state, the positive electrode non-formation region winding part 122 of the first electrode body 101 is joined to the first main surface 103a, and the positive electrode non-formation region winding part 122 of the second electrode body 102 is joined. Joined to the second main surface 103b. Further, the positive electrode current collector 131 that constitutes the positive electrode unformed region winding part 122 of both electrode bodies is also joined to each other.

  Thus, the positive electrode unformed region winding part 122 of the first electrode body 101 and the second electrode body 102 can be joined to the positive electrode terminal 103 by a single joining process. The positive terminal plate 105 prevents the positive electrode current collector 131 from being damaged by ultrasonic waves.

  FIGS. 25 and 26 are schematic views showing a method of joining the first electrode body 101 and the second electrode body 102 to the negative electrode terminal 104. As shown in FIG. 25, the negative electrode terminal 104 is inserted between the negative electrode unformed region winding part 123 of the first electrode body 101 and the second electrode body 102. Further, the negative electrode terminal plate 106 is disposed on the negative electrode non-formed region winding portion 123 of the first electrode body 101 and the second electrode body 102. In this state, the two negative terminal plates 106 are sandwiched and fixed by a clamp or the like.

  Subsequently, as shown in FIG. 26, the two negative electrode terminal plates 106 are sandwiched between the ultrasonic welding anvil 501 and the ultrasonic welding horn 502 (arrows in the figure). The thickness of this portion is, for example, a negative electrode terminal 104 having a thickness of 1.2 mm, 23 layers of a negative electrode current collector 141 having a thickness of 0.01 mm, and two negative electrode terminal plates 106 having a thickness of 0.2 mm. 10 mm.

  By applying an ultrasonic wave in this state, the negative electrode unformed region wound portion 123 of the first electrode body 101 is joined to the third main surface 104a, and the negative electrode unformed region wound portion 123 of the second electrode body 102 is joined. Joined to the fourth main surface 104b. Further, the negative electrode current collector 141 constituting the negative electrode unformed region winding part 123 of both electrode bodies is also joined to each other.

  In this manner, the negative electrode non-formed region winding portion 123 of the first electrode body 101 and the second electrode body 102 can be bonded to the negative electrode terminal 104 by a single bonding process. The negative electrode terminal plate 106 prevents the negative electrode current collector 141 from being damaged by ultrasonic waves.

  Subsequently, the positive electrode non-formed region wound part 122 and the negative electrode non-formed region wound part 123 of the first electrode body 101 and the second electrode body 102 are covered with an insulating film 107 (see FIG. 2), The outer can 108 and the lid member 109 are joined. The outer can 108 and the lid member 109 can be joined by, for example, laser welding.

  Subsequently, an electrolytic solution is injected from the injection port 109a, and the injection lid 111 is joined to the lid member 109 to seal the injection port 109a. The lid member 109 and the injection lid 111 can be joined by, for example, laser welding.

  The electrochemical device 100 can be manufactured as described above. As described above, the positive electrode non-formation region winding portion 122 of the first electrode body 101 and the second electrode body 102 can be joined to the positive electrode terminal 103 by one welding, and the negative electrode non-formation region winding portion of both electrode bodies is obtained. 123 can also be joined to the negative electrode terminal 104 by one-time welding. Thereby, the manufacturing process can be simplified, and the electrochemical device 100 can be manufactured at a low cost. In addition, the said manufacturing method is an example and you may manufacture the electrochemical device 100 with another manufacturing method.

(Second Embodiment)
A second embodiment of the present invention will be described.

[Structure of electrochemical device]
FIG. 27 is a perspective view of a partial configuration of the electrochemical device 400 according to the second embodiment. The electrochemical device 400 is different from the electrochemical device 100 according to the first embodiment in the configuration of the positive electrode terminal and the negative electrode terminal, and the other configuration is the same as that of the electrochemical device 100. Therefore, components other than the positive electrode terminal and the negative electrode terminal are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted.

  The positive terminal 403 and the negative terminal 404 are attached to the lid member 109 as in the first embodiment.

  FIG. 28 is a plan view of the positive electrode terminal 403, and FIGS. 29 and 30 are perspective views of the positive electrode terminal 403. The positive terminal 403 is a plate-shaped member made of metal. The positive electrode terminal 403 can be made of, for example, aluminum (A1050-H24). The positive terminal 403 is inserted into the lid member 109 and insulated from the lid member 109 by a terminal support member 110 made of synthetic resin or the like.

  As shown in FIGS. 28 to 30, the positive terminal 403 includes an electrode body joint portion 403a, an external terminal portion 403b, and a relay portion 403c.

  The electrode body joint portion 403a is a portion where the first electrode body 101 and the second electrode body 102 are joined. As shown in FIG. 29 and FIG. 30, one of the main surfaces of the electrode body bonding portion 403a is a first main surface 403d, and the opposite main surface is a second main surface 403e.

  The first main surface 403d is joined with the non-positive electrode region winding part 122 of the first electrode body 101, and the non-positive electrode region winding part 122 is sandwiched between the first main surface 403d and the positive terminal plate 105 (see FIG. 18). The positive electrode non-formation region winding part 122 of the second electrode body 102 is joined to the second main surface 403e, and the positive electrode non-formation region winding part 122 is sandwiched between the second main surface 403e and the positive electrode terminal plate 105 (see FIG. 18).

  The external terminal portion 403b protrudes outside the accommodation space in which the first electrode body 101, the second electrode body 102, and the electrolyte solution are accommodated, and is connected to an external device, and is used for connection to an external device or the like. A through-hole 403f is provided.

  The relay portion 403c extends in a direction orthogonal to the extending direction of the electrode body bonding portion 403a and the external terminal portion 403b, and physically and electrically connects the electrode body bonding portion 403a and the external terminal portion 403b.

  FIG. 31 is a schematic diagram showing the width of each part of the positive electrode terminal 403, and FIG. 32 is a schematic diagram showing the thickness of each part of the positive electrode terminal 403.

  As shown in FIG. 31, the width of the electrode body joint portion 403a is the first width W1, the width of the external terminal portion 403b is the second width W2, and the width of the relay portion 403c is the third width W3. Here, the first width W1 is larger than the third width W3, and the second width W2 is larger than the first width W1. That is, the width increases in the order of the third width W3, the first width W1, and the second width W2.

  Further, as shown in FIG. 32, the thickness of the electrode body joint portion 403a is the first thickness D1, the thickness of the external terminal portion 403b is the second thickness D2, and the thickness of the relay portion 403c is the third thickness D3. . Here, the first thickness D1 is larger than the second thickness D2, and the third thickness D3 is larger than the first thickness D1. That is, the thickness increases in the order of the second thickness D2, the first thickness D1, and the third thickness D3.

  Furthermore, it is preferable that the cross-sectional area (D1 × W1) of the electrode body joint portion 403a, the cross-sectional area (D2 × W2) of the external terminal portion 403b, and the cross-sectional area (D3 × W3) of the relay portion 403c are the same.

  By configuring the positive electrode terminal 403 as described above, the shape of each part can be made as required. Specifically, by increasing the width (second width W2) of the external terminal portion 403b, the diameter of the bolt inserted through the through hole 403f can be increased and the strength of the terminal support member 110 is improved. be able to.

  Further, by reducing the width of the relay portion 403c (third width W3), the volume of the electrode body (that is, the storage capacity) can be increased. Furthermore, the width (first width W1) of the electrode body joint portion 403a can be set to a minimum width necessary for ultrasonic welding of the electrode body.

  Moreover, by making the thickness of each part into the relationship as described above, the difference in cross-sectional area of each part can be reduced, and the difference in electrical resistance between the parts can be reduced. In particular, by making the cross-sectional area of each part the same, it is possible to make the electric resistance in each part uniform, which is preferable.

  FIG. 33 is a plan view of the negative electrode terminal 404, and FIGS. 34 and 35 are perspective views of the negative electrode terminal 404. The negative terminal 404 is a plate-like member made of metal. The negative electrode terminal 404 can be made of, for example, copper (C1100-1 / 4H). The negative terminal 404 is inserted into the lid member 109 and insulated from the lid member 109 by a terminal support member 110 made of synthetic resin or the like.

  As shown in FIGS. 33 to 35, the negative electrode terminal 404 includes an electrode body joint portion 404a, an external terminal portion 404b, and a relay portion 404c.

  The electrode body bonding portion 404a is a portion where the first electrode body 101 and the second electrode body 102 are bonded. As shown in FIGS. 34 and 35, one of the main surfaces of the electrode body bonding portion 404a is a first main surface 404d, and the opposite main surface is a second main surface 404e.

  The negative electrode non-formation region winding part 123 of the first electrode body 101 is joined to the first main surface 404d, and the negative electrode non-formation region winding part 123 is sandwiched between the first main surface 404d and the negative electrode terminal plate 106 (see FIG. 19). The negative electrode non-formed region winding part 123 of the second electrode body 102 is joined to the second main surface 404e, and the negative electrode non-formed region winding part 123 is sandwiched between the second main surface 404e and the negative electrode terminal plate 106 (see FIG. 19).

  The external terminal 404b protrudes outside the housing space in which the first electrode body 101, the second electrode body 102, and the electrolytic solution are housed, and is connected to an external device, and is used for connection with an external device or the like. A through hole 404f is provided.

  The relay portion 404c extends in a direction orthogonal to the extending direction of the electrode body bonding portion 404a and the external terminal portion 404b, and physically and electrically connects the electrode body bonding portion 404a and the external terminal portion 404b.

  FIG. 36 is a schematic diagram showing the width of each part of the negative electrode terminal 404, and FIG. 37 is a schematic diagram showing the thickness of each part of the negative electrode terminal 404.

  As shown in FIG. 36, the width of the electrode body bonding portion 404a is the first width V1, the width of the external terminal portion 404b is the second width V2, and the width of the relay portion 404c is the third width V3. Here, the first width V1 is larger than the third width V3, and the second width V2 is larger than the first width V1. That is, the width increases in the order of the third width V3, the first width V1, and the second width V2.

  Also, as shown in FIG. 37, the thickness of the electrode assembly joining portion 404a is the first thickness E1, the thickness of the external terminal portion 404b is the second thickness E2, and the thickness of the relay portion 404c is the third thickness E3. . Here, the first thickness E1 is larger than the second thickness E2, and the third thickness E3 is larger than the first thickness E1. That is, the thickness increases in the order of the second thickness E2, the first thickness E1, and the third thickness E3.

  Furthermore, it is preferable that the cross-sectional area (E1 × V1) of the electrode body bonding portion 404a, the cross-sectional area (E2 × V2) of the external terminal portion 404b, and the cross-sectional area (E3 × V3) of the relay portion 404c are the same.

  By configuring the negative electrode terminal 404 as described above, the shape of each part can be made as required. Specifically, by increasing the width (second width V2) of the external terminal portion 404b, the diameter of the bolt inserted into the through hole 404f can be increased and the strength of the terminal support member 110 is improved. be able to.

  Further, by reducing the width of the relay portion 404c (third width V3), the volume of the electrode body (that is, the storage capacity) can be increased. Furthermore, the width (first width V1) of the electrode body joint portion 404a can be set to a minimum width necessary for ultrasonic welding of the electrode body.

  Moreover, by making the thickness of each part into the relationship as described above, the difference in cross-sectional area of each part can be reduced, and the difference in electrical resistance between the parts can be reduced. In particular, by making the cross-sectional area of each part the same, it is possible to make the electric resistance in each part uniform, which is preferable.

  The positive terminal 403 and the negative terminal 404 are configured as described above. Note that the electrochemical device 400 does not necessarily have both the positive electrode terminal 403 and the negative electrode terminal 404, and may have at least one of the positive electrode terminal 403 and the negative electrode terminal 404.

[Method of manufacturing positive electrode terminal and negative electrode terminal]
The positive electrode terminal 403 and the negative electrode terminal 404 can be produced by processing a rolled profile. FIG. 38 is a perspective view of a rolled profile strip 600.

  The deformed strip is a metal strip having a step (unevenness) in the cross-sectional shape, and the rolled strip is processed into a deformed strip by rolling. Compared to cutting, there are features such as less material loss, small surface roughness, undulation, small bending, and no hardened layer of cutting.

  As shown in FIG. 38, the rolled profile 600 has a first portion 601 having a first thickness F1, a second portion 602 having a second thickness F2, and a third portion 603 having a third thickness F3. The first thickness F1 is greater than the second thickness F2, and the third thickness F3 is greater than the first thickness F1.

  The positive electrode terminal 403 and the negative electrode terminal 404 can be produced by cutting out the rolled profile strip 600. FIG. 39 is a schematic diagram showing a method for cutting out the rolled profile strip 600. As shown in the figure, the positive electrode terminal 403 and the negative electrode terminal 404 having the above shapes can be produced by cutting the rolled deformed strip 600 in the shape of the positive electrode terminal 403 and the negative electrode terminal 404 indicated by a line T by punching or the like.

  Note that the manufacturing method of the positive electrode terminal 403 and the negative electrode terminal 404 is not limited to cutting from the rolled deformed strip 600, and it may be manufactured by cutting and cutting a plate having a certain thickness into individual pieces. Is possible.

DESCRIPTION OF SYMBOLS 100, 400 ... Electrochemical device 101 ... 1st electrode body 102 ... 2nd electrode body 103, 403 ... Positive electrode terminal 104, 404 ... Negative electrode terminal 120 ... Electrode body 121 ... Electrode area winding part 122 ... Positive electrode non-formation area winding Part 123: Negative electrode unformed region winding part 130 ... Positive electrode 131 ... Positive electrode current collector 132 ... Positive electrode active material layer 140 ... Negative electrode 141 ... Negative electrode current collector 142 ... Negative electrode active material layer 150 ... Separator 160 ... Lithium ion supply source 170 … Turned body

As shown in FIGS. 14 and 15, one of the main surfaces of the negative electrode terminal 104 is a third main surface 104a, and the opposite main surface is a fourth main surface 104b. The negative electrode terminal 104 is provided with a through hole 104c that communicates with the third main surface 104a and the fourth main surface 104b and is used for connection with an external device or the like. The shape of the negative electrode terminal 104 is not particularly limited, and may be a plate shape. For example, the negative electrode terminal 104 may have a shape having a rectangular main surface.

Claims (12)

A positive electrode terminal that is flat and has a first main surface and a second main surface opposite to the first main surface;
A negative electrode terminal that is flat and has a third main surface and a fourth main surface opposite to the third main surface;
A first positive electrode current collector that is a metal foil; and a first positive electrode active material layer formed on the first positive electrode current collector; A first positive electrode forming region in which one positive electrode active material layer is formed and a first positive electrode non-formed region in which the first positive electrode active material layer is not formed are provided on the first positive electrode current collector. A first negative electrode current collector that is a metal foil, and a first negative electrode active material layer formed on the first negative electrode current collector, the first negative electrode A first negative electrode forming region in which the first negative electrode active material layer is formed on the current collector and a first negative electrode active material layer in which the first negative electrode active material layer is not formed on the first negative electrode current collector A first negative electrode provided with a negative electrode unformed region; a first separator separating the first positive electrode and the first negative electrode; the first positive electrode, the first negative electrode, and the first negative electrode; A first electrode body in which one separator is laminated and wound, wherein the first positive electrode unformed region wound portion is a wound portion; A first electrode body comprising a first negative electrode non-formed region wound portion that is a portion where the first negative electrode non-formed region is wound;
A second positive electrode current collector that is a metal foil; and a second positive electrode active material layer formed on the second positive electrode current collector. A second positive electrode formation region where the second positive electrode active material layer is formed, and a second positive electrode non-formation region where the second positive electrode active material layer is not formed on the second positive electrode current collector. A second negative electrode current collector that is a metal foil, and a second negative electrode active material layer formed on the second negative electrode current collector, and the second negative electrode A second negative electrode forming region in which the second negative electrode active material layer is formed on the current collector and a second in which the second negative electrode active material layer is not formed on the second negative electrode current collector A second negative electrode provided with a non-negative electrode region; a second separator separating the second positive electrode and the second negative electrode; the second positive electrode, the second negative electrode, and the second negative electrode; A second electrode body in which two separators are stacked and wound, wherein the second positive electrode unformed region is a wound portion; A second electrode body comprising a second negative electrode non-formed region wound portion that is a portion where the second negative electrode non-formed region is wound;
An electrolyte for immersing the first electrode body and the second electrode body,
The first positive electrode unformed region wound portion is bonded to the first main surface, the first negative electrode unformed region wound portion is bonded to the third main surface, and the second positive electrode uncovered region is not bonded to the first main surface. An electrochemical device in which a forming region winding portion is bonded to the second main surface, and the second negative electrode unformed region winding portion is bonded to the fourth main surface. The electrochemical device according to claim 1,
The first electrode body has a flat wound structure in which a first wound body in which the first positive electrode, the first negative electrode, and the first separator are wound is flattened into a plate shape. And
The second electrode body has a flat wound structure in which a second winding body in which the second positive electrode, the second negative electrode, and the second separator are wound is flattened into a plate shape. Electrochemical device. The electrochemical device according to claim 2,
The first electrode body further includes two lithium ion supply sources bonded to the front surface and the back surface of the first wound body,
The second electrode body further includes two lithium ion supply sources joined to the front surface and the back surface of the second wound body, respectively. A positive electrode terminal having a flat plate shape and having a first main surface and a second main surface opposite to the first main surface; and a flat plate shape having a third main surface and the third main surface; A negative electrode terminal having a fourth main surface on the opposite side; a first positive electrode current collector as a metal foil; and a first positive electrode active material layer formed on the first positive electrode current collector. The first positive electrode active material layer is formed on the first positive electrode current collector, and the first positive electrode active material layer is formed on the first positive electrode current collector. A first positive electrode provided with an unformed first positive electrode unformed region, a first negative electrode current collector that is a metal foil, and a first electrode formed on the first negative electrode current collector A first negative electrode forming region in which the first negative electrode active material layer is formed on the first negative electrode current collector and the first negative electrode current collector on the first negative electrode current collector. 1 negative electrode active material layer formed A first negative electrode provided with an unformed first negative electrode non-forming region, a first separator separating the first positive electrode and the first negative electrode, the first positive electrode, the first positive electrode, A first electrode body in which the negative electrode and the first separator are stacked and wound, and the first positive electrode unformed region is a wound portion. A first electrode body including a turn part, a first negative electrode non-formed region wound part that is a part where the first negative electrode non-formed region is wound, and a second positive electrode current collector that is a metal foil And a second positive electrode active material layer formed on the second positive electrode current collector, and the second positive electrode active material layer is formed on the second positive electrode current collector A second positive electrode non-formation region where the second positive electrode active material layer is not formed is provided on the second positive electrode formation region and the second positive electrode current collector. The second negative electrode current collector, a second negative electrode current collector that is a metal foil, and a second negative electrode active material layer formed on the second negative electrode current collector. A second negative electrode forming region in which the second negative electrode active material layer is formed on the body, and a second negative electrode in which the second negative electrode active material layer is not formed on the second negative electrode current collector A second negative electrode provided with a formation region, and a second separator separating the second positive electrode and the second negative electrode, the second positive electrode, the second negative electrode, and the second separator Is a second electrode body that is laminated and wound, wherein the second positive electrode unformed region wound portion is a portion where the second positive electrode unformed region is wound, and the second electrode body Preparing a second electrode body including a second negative electrode non-formed region wound portion which is a portion where the negative electrode non-formed region is wound,
Bonding the first positive electrode unformed region wound portion to the first main surface, bonding the second positive electrode unformed region wound portion to the second main surface,
The method of manufacturing an electrochemical device, wherein the first negative electrode unformed region wound portion is bonded to the third main surface, and the second negative electrode unformed region wound portion is bonded to the fourth main surface. A method for producing an electrochemical device according to claim 4,
Bonding the first positive electrode unformed region wound portion to the first main surface, and joining the second positive electrode unformed region wound portion to the second main surface; In the step of bonding the negative electrode non-formed region winding portion to the third main surface and bonding the second negative electrode non-formed region winding portion to the fourth main surface, bonding is performed by ultrasonic bonding. Chemical device manufacturing method. A method for producing an electrochemical device according to claim 5,
In the step of joining the first positive electrode unformed region winding part to the first main surface and joining the second positive electrode non-formed region winding part to the second main surface, Sandwiching the positive electrode non-formed region winding part and the second positive electrode non-formed region wound part by an ultrasonic bonding instrument to join the first positive electrode non-formed region wound part to the first main surface; Bonding the second positive electrode unformed region wound portion to the second main surface;
In the step of bonding the first negative electrode unformed region wound portion to the third main surface and bonding the second negative electrode unformed region wound portion to the fourth main surface, A negative electrode non-formed region wound part and the second negative electrode non-formed region wound part are sandwiched by an ultrasonic bonding tool to join the first negative electrode non-formed region wound part to the third main surface, The manufacturing method of the electrochemical device which joins the said 2nd negative electrode non-formation area | region winding part to the said 4th main surface. A positive electrode terminal that is plate-shaped and has a first main surface and a second main surface opposite to the first main surface;
A negative electrode terminal that is plate-shaped and has a third main surface and a fourth main surface opposite to the third main surface;
A first positive electrode current collector that is a metal foil; and a first positive electrode active material layer formed on the first positive electrode current collector; A first positive electrode forming region in which one positive electrode active material layer is formed and a first positive electrode non-formed region in which the first positive electrode active material layer is not formed are provided on the first positive electrode current collector. A first negative electrode current collector that is a metal foil, and a first negative electrode active material layer formed on the first negative electrode current collector, the first negative electrode A first negative electrode forming region in which the first negative electrode active material layer is formed on the current collector and a first negative electrode active material layer in which the first negative electrode active material layer is not formed on the first negative electrode current collector A first negative electrode provided with a negative electrode unformed region; a first separator separating the first positive electrode and the first negative electrode; the first positive electrode, the first negative electrode, and the first negative electrode; A first electrode body in which one separator is laminated and wound, wherein the first positive electrode unformed region wound portion is a wound portion; A first electrode body comprising a first negative electrode non-formed region wound portion that is a portion where the first negative electrode non-formed region is wound;
A second positive electrode current collector that is a metal foil; and a second positive electrode active material layer formed on the second positive electrode current collector. A second positive electrode formation region where the second positive electrode active material layer is formed, and a second positive electrode non-formation region where the second positive electrode active material layer is not formed on the second positive electrode current collector. A second negative electrode current collector that is a metal foil, and a second negative electrode active material layer formed on the second negative electrode current collector, and the second negative electrode A second negative electrode forming region in which the second negative electrode active material layer is formed on the current collector and a second in which the second negative electrode active material layer is not formed on the second negative electrode current collector A second negative electrode provided with a non-negative electrode region; a second separator separating the second positive electrode and the second negative electrode; the second positive electrode, the second negative electrode, and the second negative electrode; A second electrode body in which two separators are stacked and wound, wherein the second positive electrode unformed region is a wound portion; A second electrode body comprising a second negative electrode non-formed region wound portion that is a portion where the second negative electrode non-formed region is wound;
An electrolyte for immersing the first electrode body and the second electrode body,
The first positive electrode unformed region wound portion is bonded to the first main surface, the first negative electrode unformed region wound portion is bonded to the third main surface, and the second positive electrode uncovered region is not bonded to the first main surface. An electrochemical device in which a forming region winding portion is bonded to the second main surface, and the second negative electrode unformed region winding portion is bonded to the fourth main surface. The electrochemical device according to claim 7,
The positive electrode terminal is formed by joining the first positive electrode non-formed region wound portion and the second positive electrode non-formed region wound portion, and having an electrode body joined portion having a first width and a first thickness, A first electrode body, a second electrode body, and an external terminal portion having a second width and a second thickness protruding outside a housing space for housing the electrolytic solution; and the electrode body joint portion and the external body A terminal portion, and a relay portion having a third width and a third thickness;
The first width is greater than the third width;
The second width is greater than the first width;
The first thickness is greater than the second thickness;
The electrochemical device wherein the third thickness is greater than the first thickness. The electrochemical device according to claim 7,
In the negative electrode terminal, the first negative electrode non-formed region wound portion and the second negative electrode non-formed region wound portion are joined, and an electrode assembly joined portion having a first width and a first thickness, A first electrode body, a second electrode body, and an external terminal portion having a second width and a second thickness protruding outside a housing space for housing the electrolytic solution; and the electrode body joint portion and the external body A terminal portion, and a relay portion having a third width and a third thickness;
The first width is greater than the third width;
The second width is greater than the first width;
The first thickness is greater than the second thickness;
The electrochemical device wherein the third thickness is greater than the first thickness. The electrochemical device according to claim 7,
The positive electrode terminal is formed by joining the first positive electrode non-formed region wound portion and the second positive electrode non-formed region wound portion, and having an electrode body joined portion having a first width and a first thickness, A first electrode body, a second electrode body, and an external terminal portion having a second width and a second thickness protruding outside a housing space for housing the electrolytic solution; and the electrode body joint portion and the external body A terminal portion, and a relay portion having a third width and a third thickness;
The first width is greater than the third width;
The second width is greater than the first width;
The first thickness is greater than the second thickness;
The third thickness is greater than the first thickness;
The negative electrode terminal is bonded to the first negative electrode non-formed region wound portion and the second negative electrode non-formed region wound portion, and has an electrode body joint portion having a fourth width and a fourth thickness, A first electrode body, a second electrode body, and an external terminal portion having a fifth width and a fifth thickness protruding outside a housing space for housing the electrolyte solution; and the electrode body joint portion and the external body A terminal portion, and a relay portion having a sixth width and a sixth thickness;
The fourth width is greater than the sixth width;
The fifth width is greater than the fourth width;
The fourth thickness is greater than the fifth thickness,
The sixth thickness is greater than the fourth thickness. The electrochemical device according to claim 9, comprising:
The positive electrode terminal is an electrochemical device in which the electrode body joint portion, the external terminal portion, and the relay portion have the same cross-sectional area. The electrochemical device according to claim 10, wherein
The negative electrode terminal is an electrochemical device in which the electrode body joint portion, the external terminal portion, and the relay portion have the same cross-sectional area.