JP2016048651A - Electrode body and secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel bipolar electrode capable of suppressing self discharge, and to provide a high-performance secondary battery, including such a bipolar electrode, capable of suppressing the self discharge.SOLUTION: An electrode body 1 for a secondary battery comprises: a collector 10; a positive electrode 20 which is arranged on a first surface 101 of the collector 10 and includes a positive active material; and a negative electrode 30 which is arranged on a second surface 102 of the collector 10 and includes a negative active material. The positive active material and the negative active material include copper-based active materials or silver-based active materials. In a planar view, the collector 10 has an annular section 104 which does not overlap with the positive electrode 20 or the negative electrode 30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrode body and a secondary battery.

  Conventionally, for example, a secondary battery is used as a power source of a small electronic device. Among them, since the lithium secondary battery has a small atomic weight of lithium and a large ionization energy, it can realize a battery having a high energy density and is suitably used in the above-described applications.

  On the other hand, in a lithium secondary battery, a flammable organic electrolytic solution may be used. If the electrolytic solution volatilizes due to leakage of the electrolytic solution or driving heat generation, the electronic device may be damaged.

  In response to such a problem, an all-solid secondary battery using a silver-based or copper-based solid electrolyte having high ionic conductivity for ionic conduction between positive and negative electrodes has been developed (for example, Patent Document 1). To 6). However, in the all solid state secondary batteries described in Patent Documents 1 to 6, usable silver-based active materials and copper-based active materials are limited, and these usable silver-based active materials and copper-based active materials are limited. There is a problem that the electromotive force is low in the active material.

  As a configuration capable of increasing the electromotive force of a battery in order to solve the above problem, it is generally known to connect a plurality of unit cells in series. In particular, when a bipolar electrode body having a positive electrode and a negative electrode on both sides of one current collector is used, a plurality of single cells can be housed in one battery container, and a small and light high voltage battery can be obtained. (For example, refer to Patent Documents 7 and 8).

JP 61-122122 A JP-A-2-247978 JP 2008-84851 A JP 62-47973 A JP-A-2-162660 Japanese Patent Laid-Open No. 3-15165 JP-A-11-204136 JP 2004-71405 A

  When a bipolar electrode body is applied to an all-solid-state secondary battery as described in Patent Documents 1 to 6 and used with a secondary battery that achieves both high ionic conductivity and high electromotive force, Challenges arise.

  That is, when silver or copper is used as an active material, these elements cause ion migration (or electrochemical migration), and may cause self-discharge as a result of short-circuiting the positive electrode and the negative electrode with a bipolar electrode body. There is. Therefore, there has been a demand for a bipolar electrode body that can suppress self-discharge by suppressing ion migration.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a novel bipolar electrode body capable of suppressing self-discharge. It is another object of the present invention to provide a high-performance secondary battery having such a bipolar electrode body and suppressing self-discharge.

In order to solve the above-described problems, one embodiment of the present invention is an electrode body for a secondary battery, which includes a current collector, a positive electrode including a positive electrode active material provided on one surface of the current collector, A negative electrode including a negative electrode active material provided on the other surface of the current collector, wherein the positive electrode active material and the negative electrode active material include a copper-based active material or a silver-based active material, and the current collector Provides an electrode body characterized by having an annular portion that does not overlap the positive electrode or the negative electrode in plan view.
According to this configuration, even if ion migration occurs, it is easy to ensure a sufficient distance for suppressing a short circuit between the positive electrode and the negative electrode, and an electrode body capable of effectively suppressing self-discharge is provided. be able to.

According to an aspect of the present invention, the minimum value of the distance from the positive electrode to the negative electrode measured along the surface of the electrode body may be 2 mm or more.
According to this configuration, since a sufficient distance is ensured between the positive electrode and the negative electrode, it is possible to provide an electrode body that hardly causes a short circuit and can effectively suppress self-discharge.

According to one aspect of the present invention, the ring portion may have a surface formed of one or more metals selected from the group consisting of chromium, titanium, vanadium, tungsten, palladium, and platinum.
According to this configuration, ion migration on the surface of the annular portion can be suitably suppressed.

According to an aspect of the present invention, the ring portion has a surface formed of a thin film made of one or more metals selected from the group consisting of chromium, titanium, vanadium, tungsten, palladium, and platinum, or a water-repellent thin film. It is good also as a structure coat | covered with.
According to this configuration, even when a current collector of a general forming material such as copper or aluminum is used, ion migration on the surface of the annular portion can be suitably suppressed.

According to one aspect of the present invention, the current collector may be configured to use the metal as a forming material.
According to this configuration, ion migration on the surface of the annular portion can be suitably suppressed without performing special processing on the surface of the current collector.

According to one embodiment of the present invention, the side surface of the positive electrode, the side surface of the negative electrode, and the surface of the current collector that is not in contact with the positive electrode and the negative electrode may be covered with a water-repellent thin film. .
According to this configuration, it is possible to suppress metal elution from the positive electrode active material that is the origin of ion migration on the side surface of the positive electrode, the side surface of the negative electrode, and the surface of the current collector that is not in contact with the positive electrode and the negative electrode. The ion migration at the position can be suitably suppressed.

Another embodiment of the present invention is an electrode body for a secondary battery, which is a sheet-like current collector, a positive electrode including a positive electrode active material provided on one surface of the current collector, and the current collector A negative electrode including a negative electrode active material provided on the other surface of the body, wherein the positive electrode active material and the negative electrode active material include a copper-based active material or a silver-based active material, and the side surface of the positive electrode, the negative electrode And a surface of the current collector that is not in contact with the positive electrode and the negative electrode are coated with a water-repellent thin film.
According to this configuration, it is possible to suppress metal elution from the positive electrode active material that is the origin of ion migration on the side surface of the positive electrode, the side surface of the negative electrode, and the surface of the current collector that is not in contact with the positive electrode and the negative electrode. The ion migration at the position can be suitably suppressed. Therefore, a novel bipolar electrode body that can suppress self-discharge can be provided.

According to an aspect of the present invention, the copper-based active material is one or more selected from the group consisting of a copper chevrel phase compound, Cu _0.1 TiS ₂ , Cu _0.1 NbS ₂ , and metallic copper, and the silver The system active material may be one or more selected from the group consisting of δ-type silver vanadate, silver chromate, Ag _0.1 TiS ₂ , Ag _0.1 NbS ₂ , and metallic silver.
According to this structure, it can be set as a favorable electrode body with high ionic conductivity.

According to an aspect of the present invention, the positive electrode active material and the negative electrode active material are formed of the same material, and the same material is either the copper-based active material or the silver-based active material. It is good also as a characteristic structure.
According to this configuration, the positive electrode and the negative electrode can be used interchangeably, and work efficiency is improved when the secondary battery is assembled.

According to one embodiment of the present invention, the positive electrode active material and the negative electrode active material may be the same compound.
According to this configuration, the positive electrode and the negative electrode can be used interchangeably, and work efficiency is improved when the secondary battery is assembled.

One embodiment of the present invention includes a pair of electrodes, the electrode body disposed between the pair of electrodes, a positive electrode included in the electrode body, and one of the pair of electrodes. Provided is a secondary battery having a first solid electrolyte layer sandwiched between two electrodes, a negative electrode included in the electrode body, and a second solid electrolyte layer sandwiched between the other electrode of the pair of electrodes. .
According to this configuration, since two or more unit cells are connected in series, a secondary battery having a high electromotive force can be obtained.

According to one embodiment of the present invention, the one electrode may include a negative electrode active material, and the other electrode may include a positive electrode active material.
According to this configuration, a secondary battery in which two or more unit cells are preferably connected in series can be obtained.

According to one aspect of the present invention, a plurality of the electrode bodies are disposed between the pair of electrodes, and the third solid electrolyte is sandwiched between the positive electrode of the adjacent electrode body and the negative electrode of the electrode body. It is good also as composition which has a layer.
According to this configuration, since three or more unit cells are connected in series, a secondary battery having a higher electromotive force can be obtained.

It is explanatory drawing of the electrode body which concerns on 1st Embodiment. It is explanatory drawing of the electrode body which concerns on 2nd Embodiment. It is process drawing which shows the manufacturing method of the electrode body of 2nd Embodiment. It is process drawing which shows the manufacturing method of the electrode body of 2nd Embodiment. It is explanatory drawing which shows the electrode body which concerns on a modification. It is sectional drawing which shows the secondary battery of this embodiment.

[First Embodiment]
Hereinafter, an electrode body according to a first embodiment of the present invention will be described with reference to the drawings. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

  FIG. 1 is an explanatory view of an electrode body 1 according to the first embodiment, FIG. 1 (a) is a schematic perspective view, FIG. 1 (b) is a plan view, and FIG. 1 (c) is FIG. It is arrow sectional drawing in line segment AA.

  As shown in the figure, the electrode body 1 of the present embodiment includes a sheet-like current collector 10, a positive electrode 20 provided on one surface 101 of the current collector 10, and the other surface 102 of the current collector 10. A bipolar electrode.

  The current collector 10 is made of, for example, a conductive metal such as copper (Cu) or aluminum (Al).

  The positive electrode 20 includes a positive electrode active material. As the positive electrode active material contained in the positive electrode 20, a copper-based active material or a silver-based active material can be used.

As the copper-based active material, a copper chevrel phase compound represented by Cu _x Mo ₆ S _8-y (0 <x ≦ 4, 0 ≦ y ≦ 0.4), Cu _0.1 TiS ₂ , Cu _0.1 One or more selected from the group consisting of NbS ₂ and metallic copper can be mentioned.

As the silver-based active material, δ-type silver vanadate represented by Ag _z V ₂ O ₅ (0.3 ≦ z ≦ 0.8), silver chromate (Ag ₂ Cr ₂ O ₄ ), Ag _0.1 One or more selected from the group consisting of TiS ₂ , Ag _0.1 NbS ₂ and metallic silver can be mentioned.

  When these exemplified copper-based active materials and silver-based active materials are used, a good electrode body with high ionic conductivity can be obtained.

  In addition to the above-described positive electrode active material, a solid electrolyte, a conductive auxiliary agent, and a binder can be used for the positive electrode 20 as long as the effects of the invention are not impaired. The solid electrolyte will be described later.

Examples of the conductive aid include carbon black and acetylene black.
As the binder, a thermoplastic resin such as polyethylene, or a thermosetting resin such as an acrylic resin or an epoxy resin can be used.

  The negative electrode 30 includes a negative electrode active material. As the negative electrode active material contained in the negative electrode 30, a copper-based active material or a silver-based active material can be used. The above-mentioned thing can be used as a copper type active material and a silver type active material.

  In addition to the above-described negative electrode active material, a conductive aid or binder can be appropriately used for the negative electrode 30 as long as the effects of the invention are not impaired. As the conductive auxiliary agent and binder, those described above can be used.

  The positive electrode active material included in the positive electrode 20 and the negative electrode active material included in the negative electrode 30 may be either a copper-based active material or a silver-based active material in common. By using the same type of active material for the positive electrode 20 and the negative electrode 30, it is possible to replace the positive electrode 20 and the negative electrode 30, and work efficiency is improved when a secondary battery is assembled. For example, if the positive electrode active material included in the positive electrode 20 and the negative electrode active material included in the negative electrode 30 are the same compound (active material), the positive electrode and the negative electrode can be used completely without distinction.

  In the electrode body 1 of the present embodiment, the current collector 10 is shown as having a circular shape in plan view, but may have another shape in plan view. The size of the current collector 10 can be appropriately changed according to the design of the secondary battery that is the manufacturing purpose. The electrode body 1 of the present embodiment has a diameter indicated by a symbol W1 of 12 mm and a thickness of 0.1 mm.

  Moreover, in the electrode body 1 of this embodiment, although the positive electrode 20 and the negative electrode 30 are shown as using the cylindrical thing of circular shape in planar view, another shape may be sufficient. In the drawing, the positive electrode 20 and the negative electrode 30 are arranged so that the current collector 10 and the center of the circle overlap in a plan view. At this time, the positive electrode 20 and the negative electrode 30 do not contact the end portion 103 of the current collector 10 in a plan view, and the current collector 10 does not overlap the positive electrode 20 or the negative electrode 30 in a plan view. An exposed annular portion 104 is provided.

  The sizes of the positive electrode 20 and the negative electrode 30 are designed so that the minimum value of the distance from the positive electrode 20 to the negative electrode 30 (indicated by symbol L1 in the figure) measured along the surface of the electrode body 1 is 2 mm or more. Yes. The positive electrode 20 and the negative electrode 30 of the present embodiment have a diameter indicated by a symbol W2 of 10 mm, and the width W3 of the annular portion 104 is 1 mm. That is, the distance L1 is 2 mm or more, which is the total distance of the width W3 of the annular portion 104 of the one surface 101 and the width W3 of the annular portion of the other surface 102. Further, the positive electrode 20 has a thickness H1 of 0.5 mm to 1.0 mm, and the negative electrode 30 has a thickness H2 of 0.5 mm to 1.0 mm.

  When a copper-based active material or a silver-based active material is used for the positive electrode or the negative electrode, the copper atom or silver atom contained in these causes ion migration (electrochemical migration), resulting in a short circuit between the positive electrode and the negative electrode. There is a risk of self-discharge. However, when the distance L1 is set to 2 mm or more as in the electrode body 1 of the present embodiment, even if ion migration occurs, a sufficient distance is secured between the positive electrode and the negative electrode, so that a short circuit occurs. Therefore, an electrode body that can effectively suppress self-discharge is obtained.

  Moreover, in the electrode body 1, since the annular part 104 is provided in the electrical power collector 10, it is easy to ensure sufficient distance L1 which suppresses a short circuit between a positive electrode and a negative electrode.

  The current collector 10 may be formed of a metal selected from the group consisting of chromium (Cr), titanium (Ti), vanadium (V), tungsten (W), palladium (Pd), and platinum (Pt). These metals may be used individually by 1 type, and may use 2 or more types together. When two or more metals are used in combination, the case where two or more metals are used as an alloy is included.

  When the current collector 10 uses these metals as a forming material, the surface of the annular portion 104 is formed of these metals. Since these metal materials have an effect of suppressing ion migration, an electrode body capable of effectively suppressing self-discharge is obtained.

  According to the electrode body 1 configured as described above, self-discharge can be effectively suppressed.

[Second Embodiment]
2-4 is explanatory drawing of the electrode body which concerns on 2nd Embodiment of this invention. The electrode body of this embodiment is partially in common with the electrode body 1 of the first embodiment. The difference is that a thin film that suppresses ion migration is formed on the annular portion 104 of the current collector 10. Therefore, in this embodiment, the same code | symbol is attached | subjected about the component which is common in 1st Embodiment, and detailed description is abbreviate | omitted.

  FIG. 2 is an explanatory diagram of an electrode body 2 which is an example of the present embodiment. FIG. 2A is a schematic perspective view and corresponds to FIG. FIG. 2B is a cross-sectional view and corresponds to FIG.

  As shown in the figure, the electrode body 2 is a bipolar electrode having a sheet-like current collector 12, a positive electrode 20, and a negative electrode 30.

  The current collector 12 includes a sheet-like current collector 10 and a thin film 11 that covers the surface of the annular portion 104 of the current collector 10 (the surface not in contact with the positive electrode 20 and the negative electrode 30 of the current collector 10). doing. The positive electrode 20 is provided on one surface 101 of the current collector 10, and the negative electrode 30 is provided on the other surface 102 of the current collector 10.

  The thin film 11 can be made of a metal selected from the group consisting of chromium (Cr), titanium (Ti), vanadium (V), tungsten (W), palladium (Pd), and platinum (Pt). When the material for forming the thin film 11 is any of these metals, the material for forming the current collector 10 may be, for example, copper or aluminum. By providing such a thin film 11, the thin film 11 serves as an electrode body capable of suppressing ion migration and effectively suppressing self-discharge.

  The thin film 11 may have water repellency. Examples of the material for forming the thin film 11 include a silane coupling agent in which one or more alkyl groups or fluoroalkyl groups and one or more hydrolyzable groups are bonded to a silicon atom.

  Examples of the alkyl group include linear alkyl groups having about 1 to 20 carbon atoms, and long chain alkyl groups having about 10 to 20 carbon atoms are preferable. Examples of the fluoroalkyl group include those obtained by substituting one or more hydrogen atoms of the above alkyl group with one or more fluorine atoms. Examples of the hydrolyzable group include an alkoxy group, a halogen atom, and an amino group.

Further, HMDS (hexamethyldisiloxane) can be used as a material for forming the thin film 11.
Further, the thin film 11 may be a carbon film. The film thickness of the carbon film is, for example, 2 nm or more and 50 nm or less.

  Ion migration occurs when silver atoms and copper atoms contained in the active material are eluted with moisture. In the case where the thin film 11 has water repellency as described above, moisture that causes ion migration does not adhere to the surface of the current collector 12, so that ion migration on the surface of the current collector 12 is suppressed, and self-discharge occurs. It becomes an electrode body which can suppress effectively.

  When these thin films 11 are formed, the distance from the positive electrode 20 to the negative electrode 30 measured along the surface of the electrode body 2 may be shorter than 2 mm.

FIG. 3 is a process diagram showing a method for manufacturing the electrode body 2 of the present embodiment.
First, as shown in FIG. 3A, the electrode body 1 of the first embodiment is prepared, and the surface of the positive electrode 20 (upper surface 201 and side surface 202) and the surface of the negative electrode 30 (upper surface 301 and side surface 302) are prepared. A mask 40 for covering is formed. For example, a known resist material can be used for the mask 40.

Next, as shown in FIG. 3B, the thin film 11 is formed on the annular portion 104.
When the material for forming the thin film 11 is a metal selected from the group consisting of chromium (Cr), titanium (Ti), vanadium (V), tungsten (W), palladium (Pd), and platinum (Pt), A film can be formed by vapor deposition.
When the material for forming the thin film 11 is a silane coupling agent, it can be formed by, for example, a vapor phase method.
When the thin film 11 is a carbon film, it can be formed by resistance heating vapor deposition.

Next, as shown in FIG. 3C, the target electrode body 2 can be obtained by removing the mask 40. When the electrode body 2 is manufactured by such a method, as shown in the drawing, a gap 121 is formed between the thin film 11 and the positive electrode 20 or between the thin film 11 and the negative electrode 30.
The electrode body 2 can be manufactured as described above.

  When the thin film 11 is a water-repellent thin film, the formation position is not limited to the annular portion 104 and may cover the side surface of the positive electrode 20 or the side surface of the negative electrode 30.

  In this case, as shown in FIG. 4, after forming a mask 41 covering the upper surface 201 of the positive electrode 20 and the upper surface 301 of the negative electrode 30 in the electrode body 1 (FIG. 4A), the same manufacturing method as shown in FIG. Then, the electrode body 3 having the current collector 14 can be manufactured by forming the thin film 13 by vapor deposition or vapor phase method and removing the mask 41 (FIG. 4B).

  In the obtained electrode body 3, the thin film 13 includes one surface 101 and the other surface 102 (surface not in contact with the positive electrode 20 and the negative electrode 30 of the current collector 10) in the annular portion 104 of the current collector 10, the positive electrode The side surface 202 of 20 and the side surface 302 of the negative electrode 30 are covered.

  These electrode bodies 2 and 3 can also effectively suppress self-discharge.

  In addition, in the electrode bodies 1-3 in the said embodiment, although the positive electrode 20 and the negative electrode 30 were smaller than the electrical power collector 10 in planar view, and the annular part 104 was formed, it is not restricted to this.

  FIG. 5 is an explanatory view showing an electrode body 4 according to a modification. Fig.5 (a) is a schematic perspective view, and is a figure corresponding to Fig.1 (a). FIG.5 (b) is sectional drawing and is a figure corresponding to FIG.1 (c).

  The electrode body 4 shown in the figure is a bipolar electrode having a sheet-like current collector 10, a positive electrode 20, and a negative electrode 30.

  The positive electrode 20 and the negative electrode 30 have the same shape and the same area as the current collector 10 in plan view. The positive electrode 20 has a thickness H1 of 0.5 mm to 1.0 mm, and the negative electrode 30 has a thickness H2 of 0.5 mm to 1.0 mm.

  In addition, the positive electrode 20, the current collector 10, and the negative electrode 30 form an integral cylindrical shape. Cylindrical side surfaces (curved surfaces) formed by the positive electrode 20, the current collector 10, and the negative electrode 30 are covered with a thin film 50.

  The thin film 50 is a water-repellent thin film, and can be formed using a forming material similar to the material for forming the water-repellent thin film 11 described above. Further, the thin film 50 may be a film made of a thermoplastic resin or a thermosetting resin.

  In such an electrode body 4, the minimum value of the distance L2 from the positive electrode 20 to the negative electrode 30 measured along the surface of the electrode body 4 is good to be 2 mm or more. In that case, the thicknesses of the positive electrode 20, the negative electrode 30, the current collector 10, and the thin film 50 may be appropriately controlled according to the target value of the distance L <b> 2.

  Further, when the minimum value of the distance L2 is less than 2 mm, the thin film 50 is preferably water-repellent.

  According to such an electrode body 4, self-discharge can be effectively suppressed.

[Secondary battery]
FIG. 6 is a cross-sectional view showing the secondary battery of the present embodiment. As shown in the figure, the secondary battery 100 includes a plurality (two in the figure) of electrode bodies 1 disposed between the positive electrode part 70 and the negative electrode part 80, and between the positive electrode part 70 and the electrode body 1, Between the adjacent electrode bodies 1, there are three solid electrolyte layers 60 disposed between the electrode bodies 1 and the negative electrode portion 80.

  In the figure, of the two electrode bodies 1, the electrode body 5 is disposed on the positive electrode portion 70 side, and the electrode body 6 is disposed on the negative electrode portion 80 side.

  Of the three solid electrolyte layers 60, the one disposed between the positive electrode portion 70 and the electrode body 5 is the one disposed between the solid electrolyte layer 601, the negative electrode portion 80 and the electrode body 6. The solid electrolyte layer 602, the one disposed between the electrode body 5 and the electrode body 6 is a solid electrolyte layer 603. The solid electrolyte layer 601 corresponds to the first solid electrolyte layer in the present invention, the solid electrolyte layer 602 corresponds to the second solid electrolyte layer in the present invention, and the solid electrolyte layer 603 corresponds to the third solid electrolyte layer in the present invention.

The solid electrolyte layer 60, as the _{material, K x Rb 1-x Cu} 4 I 1.5 Cl 3.5 (0 <x <0.2), copper-based solid electrolyte such as _CuI-Cu 2 _{O-Mo 3} Or Ag—Ag ₂ O, Ag—MoO ₃ , AgI—Ag _n XO ₄ or AgI—Ag _n X ₂ O ₄ (X = W, Cr, Mo, P, V, Te, Se, As, n = 1) , 2, 3), silver based solid electrolytes such as Ag ₄ RbI ₅ can be used.

  The solid electrolyte layer 60 has a thickness of 10 μm or more and 500 μm or less, for example. The solid electrolyte layer 60 may be mixed with a binder as long as the object of the present invention is not impaired, but is preferably not mixed.

  The positive electrode unit 70 includes a current collector 710 and a positive electrode 720. The positive electrode 720 can have the same structure as the positive electrode 20 described above.

  The negative electrode unit 80 includes a current collector 810 and a negative electrode 830. The negative electrode 830 can have the same configuration as the negative electrode 30 described above.

In the secondary battery 100, the active materials of the positive electrode and the negative electrode facing each other are aligned with a copper-based active material or a silver-based active material, and the active material is used as a material for forming a solid electrolyte layer sandwiched between the positive electrode and the negative electrode. A solid electrolyte containing the same atoms as the ion conducting atoms (copper or silver) contained is selected. In the present embodiment, Ag _x V ₂ O ₅ is used as the positive electrode active material and the negative electrode active material, and Ag ₆ I ₄ WO ₄ is used as the material for forming the solid electrolyte layer 60.

  The secondary battery 100 shown in the drawing has a three-layer structure including three unit cells 150. Since the electromotive force of the unit cell 150 is 0.4V, the secondary battery 100 can obtain an electromotive force of 1.2V equivalent to the Ni-H battery. Similarly, when nine layers of unit cells 150 are stacked, an electromotive force of 3.6 V equivalent to that of a lithium ion battery can be obtained.

  According to the secondary battery 100 as described above, since the ion migration contained in the active material in the electrode body 1 is suppressed, the secondary battery 100 is a high-quality secondary battery with less self-discharge.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 1-6 ... Electrode body 10, 12, 14, 710, 810 ... Current collector, 101 ... One side, 102 ... The other side, 103 ... End part, 104 ... Ring part, 11, 13, 50 ... Thin film, 20, 720 ... positive electrode, 30, 830 ... negative electrode, 60 ... solid electrolyte layer, 601 ... first solid electrolyte layer, 602 ... second solid electrolyte layer, 603 ... third solid electrolyte layer, 100 ... secondary battery

Claims (13)

An electrode body for a secondary battery,
A current collector,
A positive electrode provided on one surface of the current collector and including a positive electrode active material;
A negative electrode including a negative electrode active material provided on the other surface of the current collector,
The positive electrode active material and the negative electrode active material include a copper-based active material or a silver-based active material,
The current collector has an annular portion that does not overlap the positive electrode or the negative electrode in plan view.   The electrode body according to claim 1, wherein a minimum value of a distance from the positive electrode to the negative electrode measured along the surface of the electrode body is 2 mm or more.   3. The electrode body according to claim 1, wherein the annular portion has a surface formed of one or more metals selected from the group consisting of chromium, titanium, vanadium, tungsten, palladium, and platinum.   The annular portion is characterized in that the surface is coated with a thin film made of one or more metals selected from the group consisting of chromium, titanium, vanadium, tungsten, palladium, platinum, or a water-repellent thin film. The electrode body according to claim 1 or 2.   The electrode body according to claim 3 or 4, wherein the current collector is made of the metal.   The side surface of the positive electrode, the side surface of the negative electrode, and the surface of the current collector that is not in contact with the positive electrode and the negative electrode are covered with a water-repellent thin film. The electrode body according to any one of the above. An electrode body for a secondary battery,
A current collector,
A positive electrode provided on one surface of the current collector and including a positive electrode active material;
A negative electrode including a negative electrode active material provided on the other surface of the current collector,
The positive electrode active material and the negative electrode active material include a copper-based active material or a silver-based active material,
An electrode body, wherein a side surface of the positive electrode, a side surface of the negative electrode, and a surface of the current collector that is not in contact with the positive electrode and the negative electrode are coated with a water-repellent thin film. The copper-based active material is one or more selected from the group consisting of a copper chevrel phase compound, Cu _0.1 TiS ₂ , Cu _0.1 NbS ₂ , and copper metal,
The silver-based active material is one or more selected from the group consisting of δ-type silver vanadate, silver chromate, Ag _0.1 TiS ₂ , Ag _0.1 NbS ₂ , and metallic silver. The electrode body according to any one of 1 to 7.   9. The positive electrode active material and the negative electrode active material are formed of the same material, and the same material is one of the copper-based active material or the silver-based active material. The electrode body according to any one of the above.   The electrode body according to claim 1, wherein the positive electrode active material and the negative electrode active material are the same compound. A pair of electrodes;
The electrode body according to any one of claims 1 to 10, disposed between the pair of electrodes,
A first solid electrolyte layer sandwiched between a positive electrode of the electrode body and one of the pair of electrodes;
A secondary battery comprising: a negative electrode included in the electrode body; and a second solid electrolyte layer sandwiched between the other electrode of the pair of electrodes.   The secondary battery according to claim 11, wherein the one electrode includes a negative electrode active material, and the other electrode includes a positive electrode active material. A plurality of the electrode bodies are disposed between the pair of electrodes,
The secondary battery according to claim 11, further comprising a third solid electrolyte layer sandwiched between a positive electrode of the adjacent electrode body and a negative electrode of the electrode body.

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