JP6284252B1 - Electrochemical cell - Google Patents

Abstract

An electrochemical cell that can be manufactured at low cost is provided. A capacitor includes a pair of electrode sheets arranged opposite to each other, and the electrode sheet is disposed on at least one surface of a current collector formed of a metal foil and a pair of main surfaces of the current collector. An electrode body 10 provided with the coated active material 13; a housing space in which the electrode body 10 and the electrolyte are stored; and an exterior body that seals the electrode body 10 and the electrolyte; and the electrode body 10, And a tab 30 drawn from the inside of the exterior body to the outside. The tab 30 includes an extension portion 36 that is integrally formed with the electrode sheet 11 and extends from the electrode body 10 to at least the outside of the storage space. The extending portion 36 is composed of a conductive portion 36a formed of metal foil, and an active material coated on the entire surface of the conductive portion 36a that is continuous with the main surface of the current collector 12 on which the active material 13 is coated. 13. [Selection] Figure 3

Description

  The present invention relates to an electrochemical cell.

  Electrochemical cells such as non-aqueous electrolyte secondary batteries and electric double layer capacitors are used as power sources for various devices. As one form of the electrochemical cell, for example, a battery described in Patent Document 1 has been proposed. In the battery described in Patent Document 1, an electrode body composed of positive and negative bipolar plates is housed in an internal space of an exterior body composed of a sheet body, an outer periphery of the exterior body is sealed, and a tab connected to the electrode body is an outer periphery. Is extended to the outside. Furthermore, in the battery described in Patent Document 1, a tab is connected to the surface of the core exposed portion in each of the positive electrode plate and the negative electrode plate.

JP-A-2005-243524

  By the way, generally a positive electrode plate and a negative electrode plate are formed by cutting out from the sheet-like member by which the active material was arrange | positioned on the surface of metal foil. For this reason, in the battery of the above prior art, the positive electrode plate and the negative electrode plate have the sheet shape having a region where the active material is disposed and a region where the active material is not disposed in order to provide the core exposed portion. It can form by cutting out so that it may straddle each area | region from this member.

  However, when forming the sheet-like member provided with the region where the active material is disposed and the region where the active material is not disposed, the active material is placed only at a predetermined position on the surface of the metal foil. It becomes necessary to arrange. For this reason, the process which arrange | positions an active material on the surface of metal foil becomes complicated, and member cost may rise. Further, when cutting out the positive electrode plate or the negative electrode plate from the sheet-like member, it is necessary to align the positions to be cut out so that the area of the core exposed portion becomes a predetermined area. For this reason, the process of cutting out the positive electrode plate or the negative electrode plate becomes complicated, and the manufacturing cost may increase.

  Therefore, the present invention provides an electrochemical cell that can be manufactured at low cost.

The electrochemical cell of the present invention includes a pair of electrode sheets opposed to each other, and the electrode sheet is applied to at least one surface of a current collector formed of a metal foil and a pair of main surfaces of the current collector. An electrode body comprising the engineered active material, a housing space for housing the electrode body and the electrolyte, an exterior body for sealing the electrode body and the electrolyte, and a connection to the electrode body, the exterior A tab drawn from the inside of the body to the outside, and the tab includes an extension part that is integrally formed with the electrode sheet and extends from the electrode body to at least the outside of the storage space, and the extension part includes: A conductive portion formed of the metal foil; and the active material coated on the entire surface of the conductive portion continuous with the main surface on which the active material of the current collector is coated. The tab at the first end A joining tab that is joined to the extension portion and is conductive and has a second end disposed outside the exterior body; and a joining portion in which the extension portion and the joining tab are joined; and The exterior body is formed by stacking sheets, and the exterior body includes a storage portion in which the storage space is formed between the sheets, and a peripheral portion in which the sheet is overlapped around the storage portion. The tab is pulled out from the inside of the exterior body through the sheets overlapped at the peripheral edge, and the exterior body is interposed between the sheet and the tab at the peripheral edge. A sealant film sandwiching the tab, and the joint is sandwiched between the sealant films .

According to the present invention, the tab includes an extension part integrally formed with the electrode sheet, and the extension part is a conductive part formed of the metal foil forming the current collector, and the current collector among the conductive parts. An active material coated on the entire surface continuous with the main surface coated with the active material, so that the component in which the electrode sheet and the extension part are integrated is formed on the entire surface of the metal foil. Can be cut out from the coated sheet-like member. Therefore, the process of arranging the active material on the surface of the metal foil during the formation of the sheet-like member is simplified compared to the case where the electrode sheet is cut out from the sheet-like member having a region where the active material is not applied. This can reduce the member cost. Moreover, the process of cutting out the component in which the electrode sheet and the extending portion are integrated can be simplified to suppress an increase in manufacturing cost. Therefore, the electrochemical cell can be manufactured at a low cost.
And since a junction part is pinched | interposed into the sealant film, a junction tab is not arrange | positioned in storage space. For this reason, since a joining tab does not contact electrolyte, it becomes possible to use the member which is easy to corrode with respect to electrolyte as a member which forms a joining tab. Furthermore, since only the joining tab among the tabs can be arranged outside the exterior body, the joining tab can be formed of a member having a higher strength than the extending portion. Therefore, corrosion and breakage of the tab can be suppressed, and the reliability of the electrochemical cell can be improved.

  In the above electrochemical cell, it is desirable that the electrode cell is continuous with a fold.

  According to the present invention, a part in which an electrode sheet and an extension part are integrated is cut out from a sheet-like member in which an active material is coated on the entire surface of the metal foil, and then the part that becomes the electrode sheet and the extension An electrode sheet and an extension part can be formed by making a cut between the part to be the part and folding back the part to be the extension part with respect to the part to be the electrode sheet. For this reason, the component in which the electrode sheet and the extending portion are integrated can be cut out from the sheet-like member into, for example, a strip shape or a rectangular shape. Thereby, it becomes possible to cut out a plurality of parts in which the electrode sheet and the extending portion are integrated from the sheet-like member without gaps. Therefore, the material can be used without waste during the production of the electrode sheet and the extending portion, and the production cost of the electrochemical cell can be reduced.

  In the electrochemical cell, the joining tab includes a first part and a second part that sandwich the extension part in the thickness direction of the extension part in the joint part, and the first part and the second part are It is desirable that they are connected to each other on both sides in the width direction of the extension part across the extension part.

  According to the present invention, since the joining tab surrounds the extending portion by the first portion and the second portion in the joining portion, the joining tab and the extending portion can be hardly separated. Therefore, it is possible to improve the bonding strength between the bonding tab and the extending portion at the bonding portion.

  ADVANTAGE OF THE INVENTION According to this invention, the electrochemical cell which can be manufactured at low cost can be provided.

1 is an external perspective view of a capacitor according to a first embodiment. It is an external appearance perspective view which shows the usage example of the capacitor which concerns on 1st Embodiment. It is the top view which developed the electrode sheet concerning a 1st embodiment. It is explanatory drawing which shows the connection of a tab and a contact, Comprising: It is a top view of a tab and a contact. It is a top view of a contact and a lead frame. It is the top view which expand | deployed the electrode sheet which concerns on the modification of 1st Embodiment. It is the top view which developed the electrode sheet concerning a 2nd embodiment. It is explanatory drawing of the capacitor which concerns on 2nd Embodiment, Comprising: It is sectional drawing in the part corresponded in the VIII-VIII line of FIG. It is a perspective view which shows the formation method of the tab which concerns on 2nd Embodiment. It is a perspective view which shows the formation method of the tab which concerns on the modification of 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, an electric double layer capacitor (hereinafter simply referred to as “capacitor”) will be described as an example of the electrochemical cell. Moreover, in the following description, the same code | symbol is attached | subjected to the structure which has the same or similar function. And the overlapping description of these structures may be omitted.

[First Embodiment]
First, the capacitor 1 of the first embodiment will be described.
FIG. 1 is an external perspective view of the capacitor according to the first embodiment. FIG. 2 is an external perspective view showing a usage example of the capacitor according to the first embodiment.
As shown in FIG. 1, the capacitor 1 is connected to the electrode body 10, the exterior body 20 that seals the electrode body 10, and the interior of the exterior body 20, and is drawn out from the interior of the exterior body 20. And a connector 40 disposed outside the outer package 20 and connectable to the mating connector 91 (see FIG. 2). As shown in FIG. 2, the capacitor 1 is used by being attached to, for example, a circuit board 93 provided with a mating connector 91.

FIG. 3 is a developed plan view of the electrode sheet according to the first embodiment. FIG. 3 shows a state in which a part of the active material 13 described later is peeled off.
As shown in FIGS. 1 and 3, the electrode body 10 includes a pair of electrode sheets 11 disposed to face each other with a separator (not shown) interposed therebetween. The electrode body 10 is formed in a rectangular parallelepiped shape, for example, by winding a pair of electrode sheets 11. The pair of electrode sheets 11 are a positive electrode sheet 11 and a negative electrode sheet 11.

  As shown in FIG. 3, the electrode sheet 11 is an active material coated on at least one side (both sides in the present embodiment) of a current collector 12 formed of a metal foil and a pair of main surfaces of the current collector 12. And a substance 13. The metal foil that forms the current collector 12 is made of, for example, aluminum or an aluminum alloy. The current collector 12 has a thickness of, for example, 10 μm or more. Since the current collector 12 is integrally formed with a conducting portion 36a of the extending portion 36 described later, it is desirable that the current collector 12 has a thickness of 30 μm or more in order to ensure the strength of the extending portion 36. The active material 13 is, for example, activated carbon or carbon. The active material 13 is applied to the entire main surface of the current collector 12 as a paste mixed with a conductive additive, a binder, a dispersant, and the like. The layer of the active material 13 is desirably set to a thickness of 50 μm or less, for example. Each electrode sheet 11 is cut into a strip shape.

  As shown in FIG. 1, the exterior body 20 forms a storage space in which the electrode body 10 and an electrolytic solution (electrolyte) are stored, and seals the electrode body 10 and the electrolytic solution. The exterior body 20 is formed by overlapping rectangular sheets. In the present embodiment, the exterior body 20 is folded in half between the first sheet portion 20a and the second sheet portion 20b of one rectangular sheet, and the outer body 20 is formed along the three sides excluding the sheet fold 20c. The first sheet portion 20a and the second sheet portion 20b are formed by heat-sealing. In the following description, the overlapping direction of the first sheet portion 20a and the second sheet portion 20b is defined as the vertical direction, and the second sheet portion 20b side with respect to the first sheet portion 20a is defined as the upper side.

  The sheet | seat which forms the exterior body 20 is a laminate film which has metal foil, the resin layer provided in the overlapping surface (inner surface), and the protective layer provided in the outer surface. The metal foil is formed using, for example, a metal material that blocks outside air and water vapor such as aluminum and stainless steel. The resin layer on the overlapping surface is formed using, for example, a thermoplastic resin such as polyolefin polyethylene or polypropylene. The outer protective layer is formed using, for example, a polyester resin such as polyethylene terephthalate or a nylon resin. The resin layer on the overlapping surface and the protective layer on the outer surface are bonded to the metal foil by thermal fusion or an adhesive via a bonding layer.

  The exterior body 20 includes a storage part 21 in which the storage space is formed between the first sheet part 20a and the second sheet part 20b, and the first sheet part 20a and the second sheet part 20b around the storage part 21. The overlapped peripheral edge portion 22 and the sealant film 25 disposed between the first sheet portion 20a and the second sheet portion 20b in the peripheral edge portion 22 are provided. The outer package 20 is overlapped at the peripheral portion 22 so that the resin layers of the above-described sheets are in contact with each other. The storage portion 21 is formed so as to bulge upward with respect to the peripheral edge portion 22. Of the peripheral edge portion 22, the portions on both sides sandwiching the storage portion 21 in the extending direction of the sheet fold line 20 c are bent substantially upward at right angles along the storage portion 21. The exterior body 20 seals the electrode body 10 in the storage portion 21 by welding the first sheet portion 20 a and the second sheet portion 20 b at the peripheral edge portion 22. The sealant film 25 will be described later.

The tab 30 is a terminal for taking out electric power from the electrode body 10. The tab 30 includes a positive electrode tab 31 and a negative electrode tab 32. The positive electrode tab 31 is connected to the positive electrode sheet 11 (see FIG. 3 ). The negative electrode tab 32 is connected to the electrode sheet 11 for the negative electrode. Since the positive electrode tab 31 and the negative electrode tab 32 are formed in the same manner, the positive electrode tab 31 and the negative electrode tab 32 are collectively referred to as a tab 30 below.

  As shown in FIG. 3, the tab 30 includes an extending portion 36 that is integrally formed with the electrode sheet 11 and extends from the electrode body 10 to the outside of the storage space. In the present embodiment, the extending portion 36 extends to the outside of the exterior body 20 (see FIG. 1). The extending portion 36 is formed in a belt shape extending with a substantially constant width. The extending portion 36 includes a conductive portion 36a integrally formed with the current collector 12 by a metal foil that forms the current collector 12, and a main surface on which the active material 13 of the current collector 12 is coated in the conductive portion 36a. And an active material 13 coated on the entire surface continuous with both main surfaces in the present embodiment. The extending portion 36 is formed together with the electrode sheet 11 by cutting out from the sheet-like member in which the active material 13 is coated on the entire surface of the metal foil together with the electrode sheet 11.

  The tab 30 projects from the end of the electrode body 10 in the winding axis direction along the winding axis direction of the electrode body 10. As shown in FIG. 1, the tab 30 passes between the first sheet portion 20 a and the second sheet portion 20 b on the opposite side of the sheet fold 20 c across the storage portion 21 in the peripheral portion 22 of the exterior body 20. The exterior body 20 is pulled out from the inside. The positive electrode tab 31 and the negative electrode tab 32 are provided in a state of being parallel and spaced apart from each other.

  The sealant film 25 is interposed between the first sheet portion 20 a and the second sheet portion 20 b that form the exterior body 20 and the tab 30. The sealant film 25 is formed of a pair of film materials, and sandwiches the positive electrode tab 31 and the negative electrode tab 32 together at a position overlapping the peripheral edge portion 22 when viewed from the vertical direction. The film material that forms the sealant film 25 is formed of a thermoplastic resin such as polyolefin, polyethylene, or polypropylene. The sealant film 25 is welded and fixed to the first sheet portion 20 a and the second sheet portion 20 b, and the positive electrode tab 31 and the negative electrode tab 32 at the peripheral edge portion 22. Thereby, the airtightness and liquid tightness of storage space are improved.

  The connector 40 is provided so as to be connectable to a mating connector 91 (see FIG. 2). The connector 40 includes a housing 41 fitted to the base of the mating connector 91 and a pair of contacts 42 held by the housing 41 and conducted to the mating contact of the mating connector 91.

  One contact 42 is caulked to an end portion located outside the exterior body 20 in the extending portion 36 (see FIG. 3) of the positive electrode tab 31. The other contact 42 is caulked to an end portion of the extended portion 36 of the negative electrode tab 32 located outside the exterior body 20.

FIG. 4 is an explanatory view showing the connection between the tab and the contact, and is a plan view of the tab and the contact.
As shown in FIG. 4, the contact 42 includes a contact portion 42 a that contacts a mating contact included in the mating connector 91 (see FIG. 2), and a caulking portion that is integrally formed with the contact portion 42 a and caulked to the extending portion 36. 42b. The caulking portion 42b is formed in a U shape in a state where the caulking portion 36 is not caulked, and the caulking portion 36b is caulked so as to close the opening in a state where the tip of the extending portion 36 is disposed on the inner side. Crimp to. In the present embodiment, the caulking portion 42b is electrically connected to the conducting portion 36a through the layer of the active material 13 applied to the surface of the conducting portion 36a by being caulked by the extending portion 36.

FIG. 5 is a plan view of the contact and the lead frame.
As shown in FIG. 5, a plurality of contacts 42 are prepared in a state of being connected to the lead frame 43 side by side. The lead frame 43 is a plate-like member formed integrally with each contact 42. When connecting the extension part 36 to the connector 40, after connecting the extension part 36 to the contact 42, the contact 42 is separated from the lead frame 43 and the contact 42 is fixed to the housing 41.

  As described above, according to the present embodiment, the tab 30 includes the extending portion 36 integrally formed with the electrode sheet 11, and the extending portion 36 is a conducting portion formed by the metal foil that forms the current collector 12. 36a and the active material coated on the entire surface of the current collector 12 that is continuous with the main surface of the current collector 12 coated with the active material 13, the electrode sheet 11 and the extending portion 36 are provided. Can be cut out from a sheet-like member in which the active material 13 is coated on the entire surface of the metal foil. Therefore, compared with the case where the electrode sheet is cut out from the sheet-like member having a region where the active material is not applied as in the prior art, the active material 13 is applied to the surface of the metal foil when the sheet-like member is formed. The process of arranging can be simplified and the member cost can be reduced. Moreover, the process of cutting out the component in which the electrode sheet 11 and the extending portion 36 are integrated can be simplified to suppress an increase in manufacturing cost. Therefore, the capacitor 1 can be manufactured at low cost.

  Further, the contact 42 of the connector 40 is caulked to the extending portion 36. According to this configuration, since the contact 42 is caulked to the extended portion 36, the contact 42 penetrates the layer of the active material 13 applied to the conductive portion 36 a, and therefore the conductive portion 36 a of the contact 42 and the extended portion 36. Can be conducted. Therefore, the connector 40 can be attached to the tab 30 with a simple configuration without using a lead wire or the like. Therefore, the capacitor 1 that can be easily connected to an external device by attaching the connector 40 can be manufactured at low cost.

  As in the modification of the first embodiment shown in FIG. 6, the extending portion 36 may be connected to the electrode sheet 11 via the fold 16. Specifically, the extending portion 36 has one short side and a pair of members extending from a sheet-like member in which the active material 13 is coated on the entire surface of the metal foil. It is formed by making a cut corresponding to the long side and folding back a portion surrounded by the cut. Therefore, a plurality of parts in which the electrode sheet 11 and the extending portion 36 are integrated can be cut out from the sheet-like member without gaps. Therefore, the material can be used without waste when manufacturing the electrode sheet 11 and the extending portion 36, and the manufacturing cost of the capacitor 1 can be reduced.

[Second Embodiment]
Next, a second embodiment will be described.
FIG. 7 is a plan view of the developed electrode sheet according to the second embodiment. FIG. 8 is an explanatory diagram of the capacitor according to the second embodiment, and is a cross-sectional view of a portion corresponding to the line VIII-VIII in FIG. FIG. 7 shows a state where a part of the active material 13 is peeled off.
The second embodiment shown in FIG. 7 is different from the first embodiment in that the tab 130 includes an extending portion 136 and a joining tab 137.

  As shown in FIGS. 7 and 8, the tab 130 is integrally formed with the electrode sheet 11 and extends from the electrode body 10 to the outside of the storage space, and is joined to the extension 136 at the first end 137a. And a joining tab 137 in which the second end portion 137b is disposed outside the exterior body 20, and a joining portion 135 in which the extending portion 136 and the joining tab 137 are joined, and has a strip shape as a whole. ing. The extending portion 136 is formed in a belt shape extending with a substantially constant width. The extending portion 136 includes a conductive portion 136a integrally formed with the current collector 12 by a metal foil that forms the current collector 12, and a main surface on which the active material 13 of the current collector 12 is coated in the conductive portion 136a. And an active material 13 coated on the entire surface continuous with both main surfaces in the present embodiment. The leading end of the extension part 136 is sandwiched between the sealant films 25. The extending portion 136 is formed together with the electrode sheet 11 by cutting out from the sheet-like member in which the active material 13 is coated on the entire surface of the metal foil together with the electrode sheet 11.

The joining tab 137 is formed in a band shape from a metal material such as nickel or aluminum. The first end portion 137a of the bonding tab 137 is disposed at a position overlapping the sealant film 25 when viewed in the vertical direction, and is bonded to the distal end portion of the extending portion 136. The joining tab 137 may be connected to the contact 42 of the connector 40 by caulking, for example, as in the first embodiment, or may be joined to an external device by welding or the like. In addition, when joining the joint tab 137 with an external apparatus by welding, in order to ensure the connectivity by welding, it is desirable to form the joining tab 137 with nickel.
The joint part 135 is sandwiched between the sealant films 25. Thereby, the part located in the exterior of the exterior body 20 in the tab 130 is formed only by the joining tab 137.

Hereinafter, the joining between the joining tab 137 and the extending portion 136 will be described in detail.
FIG. 9 is a perspective view showing a tab forming method according to the second embodiment.
As shown in FIGS. 8 and 9, the joining tab 137 includes a first portion 137 c and a second portion 137 d that sandwich the extending portion 136 in the joining portion 135 in the thickness direction of the extending portion 136. As shown in FIG. 9, the joining tab 137 before joining includes a main body portion 138 extending linearly and an extending piece extending from the main body portion 138 so as to be orthogonal to the main body portion 138 at the first end 137 a. 139. The joining tab 137 is joined to the extending portion 136 in a state in which the extending piece 139 is folded back and the distal end portion of the extending portion 136 is sandwiched. As a result, the joining tab 137 is in a state where the tip end portion of the extending portion 136 is sandwiched between the first portion 137c and the second portion 137d (see FIG. 8) at the first end portion 137a. In this state, the joining tab 137 and the extending portion 136 are joined by, for example, ultrasonic welding, resistance welding, laser welding, needle caulking, or the like.

  In addition, since the layer of the active material 13 is interposed between the conducting portion 136a of the extending portion 136 and the joining tab 137, the conducting portion 136a and the joining tab 137 of the extending portion 136 are joined by ultrasonic welding or resistance welding. It is difficult to join. For this reason, when joining the joining tab 137 and the extension part 136 by ultrasonic welding or resistance welding, the first end part 137a of the joining tab 137 is wider than the tip part of the extension part 136. It is desirable to form the extension piece 139 and join the joining tabs 137 together on both sides in the width direction across the extension portion 136. As a result, the first portion 137c and the second portion 137d are coupled to each other on both sides in the width direction across the extending portion 136.

  Thus, in this embodiment, since the junction part 135 is pinched | interposed into the sealant film 25, the junction tab 137 is not arrange | positioned in storage space. For this reason, since the joining tab 137 does not come into contact with the electrolytic solution, a member such as nickel that easily corrodes the electrolytic solution can be used as a member that forms the joining tab 137. Furthermore, since only the joining tab 137 of the tabs 130 can be disposed outside the exterior body 20, the joining tab 137 can be formed of a member having a higher strength than the extending portion 136. Therefore, corrosion or breakage of the tab 130 can be suppressed, and the reliability of the capacitor 1 can be improved.

  The first portion 137c and the second portion 137d that sandwich the extension portion 136 are connected to each other on both sides in the width direction across the extension portion 136. Thereby, since the joining tab 137 surrounds the extension portion 136 by the first portion 137c and the second portion 137d in the joining portion 135, the joining tab 137 and the extension portion 136 can be hardly separated. Therefore, the joint strength between the joint tab 137 and the extension part 136 in the joint part 135 can be improved.

  In addition, joining of the joining tab 137 and the extension part 136 is not limited to the form mentioned above. For example, as in the modification of the second embodiment shown in FIG. 10, the joining tab 137 includes a strip-shaped main body 138 extending linearly, a long strip-shaped hoop material 60 supplied from, for example, a reel, The structure which pinches | interposes the front-end | tip part of the extension part 136 may be sufficient. In this case, after joining the joining tab 137 and the extending portion 136, unnecessary portions of the hoop material 60 are cut at, for example, the positions indicated by the two-dot chain line in the drawing. Thereby, the joining tab 137 is in a state in which the distal end portion of the extending portion 136 is sandwiched between the first portion 137c and the second portion 137d at the first end portion 137a.

  However, as in the second embodiment described above, when the joining tab 137 and the extension portion 136 are joined by ultrasonic welding or resistance welding, the metal foil of the extension portion 136 and the joining tab 137 are joined. Is difficult. For this reason, at least a portion of the main body 138 corresponding to the first end 137a is wider than the extension 136 so that the first end 137a of the joining tab 137 is wider than the tip of the extension 136. It is desirable that the main body 138 and the hoop material 60 are bonded to each other in the width direction across the extending portion 136.

  Further, when the joining tab 137 is constituted by the main body 138 and the hoop material 60, the main body 138 may be formed by a rod-shaped member. In this case, it is desirable that the portion of the main body 138 corresponding to the first end 137a is deformed into a plate shape by a press or the like.

The present invention is not limited to the above-described embodiment described with reference to the drawings, and various modifications can be considered within the technical scope thereof.
For example, in the above-described embodiment, an electric double layer capacitor has been described as an example of an electrochemical cell. However, the present invention is not limited to this. For example, the above-described configuration is applied to a nonaqueous electrolyte secondary battery, a primary battery, or the like. Also good.

  Moreover, in the said embodiment, although the active material 13 is coated on both surfaces of the electrode sheet 11 and the extension parts 36 and 136 of the tabs 30 and 130, it is not limited to this. The active material 13 only needs to be coated on one surface of the current collector 12 and on a surface that is continuous with the main surface of the current collector 12 on which the active material of the current collector 12 is coated. Thereby, the component in which the electrode sheet 11 and the extending portions 36 and 136 are integrated can be cut out from the sheet-like member in which the active material is coated on the entire one surface of the metal foil, and the above-described effects are exhibited. Can do.

Moreover, in the said embodiment, although the exterior body 20 is formed by folding one sheet into two, it is not limited to this, For example, even if it forms by overlapping two sheets Good.
Moreover, in the said embodiment, although the electrode body 10 is formed in the rectangular parallelepiped shape, it is not limited to this, For example, you may form in the column shape. In addition, the shape of the storage portion 21 of the exterior body 20 can be appropriately changed according to the shape of the electrode body 10.

  Moreover, in the said embodiment, although the peripheral part 22 of the exterior body 20 is bent once so that the accommodating part 21 may be followed, it is not limited to this. The peripheral edge portion 22 may be bent a plurality of times so as to involve the end surfaces of the first sheet portion 20a and the second sheet portion 20b. Thereby, it becomes possible to ensure more width of the peripheral portion 22 without increasing the size of the exterior body 20 in the vertical direction, and it is possible to further improve the air tightness and liquid tightness inside the storage portion 21. Become. Moreover, the peripheral part 22 does not need to be bent.

  In addition, it is possible to appropriately replace the constituent elements in the above-described embodiments with well-known constituent elements without departing from the spirit of the present invention, and the above-described embodiments and modifications may be appropriately combined. Good.

  DESCRIPTION OF SYMBOLS 1 ... Capacitor (electrochemical cell) 10 ... Electrode body 11 ... Electrode sheet 12 ... Current collector 13 ... Active material 16 ... Fold 20 ... Exterior body 20a ... 1st sheet | seat part (sheet | seat) 20b ... 2nd sheet | seat part (sheet | seat) DESCRIPTION OF SYMBOLS 21 ... Storage part 22 ... Peripheral part 25 ... Sealant film 30, 130 ... Tab 31 ... Positive electrode tab (tab) 32 ... Negative electrode tab (tab) 36, 136 ... Extension part 36a, 136a ... Conductive part 40 ... Connector 41 ... Housing 42 ... contact 91 ... mating connector 135 ... joint 137 ... joint tab 137a ... first end 137b ... second end 137c ... first part 137d ... second part

Claims (3)

The electrode sheet includes a current collector formed of a metal foil and an active material coated on at least one surface of the pair of main surfaces of the current collector. An electrode body comprising:
Forming an accommodation space for accommodating the electrode body and the electrolyte, and an exterior body for sealing the electrode body and the electrolyte;
A tab connected to the electrode body and drawn out from the inside of the exterior body;
With
The tab includes an extending portion that is integrally formed with the electrode sheet and extends from the electrode body to at least the outside of the storage space,
The extension part is
A conductive portion formed of the metal foil;
The active material applied to the entire surface continuous with the main surface to which the active material of the current collector is applied in the conductive portion;
Equipped with a,
The tab is
A joining tab which is joined to the extension portion at the first end portion and is conductive and the second end portion is disposed outside the exterior body; and
A joint where the extension and the joint tab are joined;
Further comprising
The exterior body is formed by overlapping sheets,
The exterior body is
A storage section in which the storage space is formed between the sheets;
A peripheral portion where the sheets are superimposed around the storage portion;
With
The tab is pulled out from the inside of the exterior body through the sheets overlapped at the peripheral edge,
The exterior body further includes a sealant film that is interposed between the sheet and the tab at the peripheral edge portion and sandwiches the tab.
The joint is sandwiched between the sealant films,
An electrochemical cell characterized by that. The extension part is connected to the electrode sheet through a fold,
The electrochemical cell according to claim 1. The joint tab includes a first part and a second part sandwiching the extension part in the thickness direction of the extension part in the joint part,
The first part and the second part are connected to each other on both sides in the width direction of the extension part across the extension part,
The electrochemical cell according to claim 1 or 2 , wherein

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