JPH05166552A - Solid electrolyte mold and its electrode mold and total solid electrochemical element equipped with both mold - Google Patents

Abstract

PURPOSE:To provide a solid electrolyte mold made using silver halide-oxygen acid silver type solid electrolyte and having stable characteristics at high temperatures, an electrolyte mold for use with the solid electrolyte mold, and a total solid electrochemical element having both of the molds. CONSTITUTION:A solid electrochemical element includes a solid electrolyte sheet 9 containing silver halide-oxygen acid silver type solid electrolyte and polyester resin, positive and negative electrode sheets 7, 8 both having active material and polyester resin, the active material acting as such on silver ion conductive solid electrolyte.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a sheet-like molded body of a solid electrolyte used for a battery or a chemical sensor,
The present invention relates to a solid electrolyte molded body whose mobile ions are silver ions, a sheet-shaped electrode molded body used together with the molded body, and an all-solid-state electrochemical device using both molded bodies.

[0002]

2. Description of the Related Art Conventionally, most electrochemical devices using electrochemical reactions such as batteries use a liquid as an electrolyte, so that the electrolyte may leak or freeze at low temperature and freeze at high temperature. Due to problems such as evaporation, the operating temperature range was limited. In order to solve these problems, improve reliability, and reduce the size and thickness of electrochemical devices,
Attempts have been made to solidify the entire electrochemical device by using a solid electrolyte instead of a liquid electrolyte.

Such an all-solid-state electrochemical element includes an all-solid-state battery, a chemical sensor such as an oxygen sensor, an analog memory, and the like. The structure thereof is a pellet of a powder of a solid electrolyte and an electrode material by a pressure molding method. There is a method of forming a thin film by a method of forming a film or a vapor deposition method.
Since the vapor deposition method has more complicated steps and higher cost than the pressure molding method, the pressure molding method is currently mainly used.

However, since the inorganic solid electrolyte is in powder form and the pellets formed by the pressure molding method are hard and brittle, the pellets may crack or break during the construction of the electrochemical device. I was afraid.

In order to solve this problem, the solid electrolyte powder is mixed with a binder such as a synthetic rubber to form the solid electrolyte and the electrode into a flexible sheet shape to improve the workability. Is being carried out.

However, among solid electrolytes, aAgX-bA is chemically stable and is expected to be applied to practical devices.
g ₂ O-cM _m1 O _n1 or pAgX-qAgM _m2 O
_n2 (where X is one or more elements selected from I, Br and Cl: M is W, Mo, Si, V, Cr,
The silver ion conductive solid electrolyte consisting of silver halide-silver oxynate represented by one or more elements selected from P and B) has a strong oxidizing power and is formed into a sheet shape or the like. When used, the resin used as the binder tends to oxidize at high temperature.

For example, a silver halide monoenzymatic acid silver-based solid
4AgI-Ag as an example of electrolyte ₂WO_FourRepresented by
In the case of a solid electrolyte, the reaction shown in (Chemical Formula 1) occurs.

[0008]

[Chemical 1]

As a result, there is a problem that not only the resin is not oxidized and the binding action is not fulfilled, but also the solid electrolyte is decomposed so that the ionic conductivity thereof is lowered.

Further, in this decomposition reaction, metallic silver is produced as represented by (Chemical formula 1). Since this metallic silver has electronic conductivity, there is a problem in that when an electrochemical device is constructed using such a fixed electrolyte sheet, the leak current of the device increases.

Further, in order to increase the reaction area in which an electrochemical reaction occurs, the electrode used when forming the all-solid-state electrochemical device employs a method of mixing an electrode active material and a solid electrolyte. The metallic silver generated by (Chemical Formula 1) acts as an active material in the electrochemical element using the silver ion conductive solid electrolyte, and the capacity balance between the positive and negative electrodes is also destroyed. In particular, in the case of an electrochemical element using a silver ion conductive solid electrolyte, metallic silver easily grows in a dendrite form due to its electrode reaction, and metallic silver generated in (Chemical Formula 1) easily becomes the nucleus of its growth. There has been a problem that dendrite grows as the electrochemical element is operated, and a short circuit between the positive electrode and the negative electrode or separation between the electrode and the electrolyte is likely to occur.

[0012]

SUMMARY OF THE INVENTION A silver ion conductive solid electrolyte comprising silver halide-silver oxynate, an electrode used together with the same and an electrochemical device using the same electrolyte and the same electrode are chemically stable. Although it is expected to be put to practical use, the problem is that it has a strong oxidizing power and reduces the binding action of the binder resin, or decomposes the solid electrolyte to reduce ionic conductivity. In addition, metallic silver produced by the decomposition reaction increases the leak current of the electrochemical element and acts as an active material,
The point is that the capacity balance between the positive and negative electrodes is disturbed, dendrites are generated, and the positive and negative electrodes are short-circuited or the electrode and the electrolyte are separated.

That is, the problem with the silver ion conductive solid electrolyte molded body is that its strong oxidative power and decomposition lower the electrical conductivity and electronic insulation properties, and the electrode molded body used with the electrolyte molded body and both of them. It has been a point that the all-solid-state electrochemical device using the molded body becomes unstable after storage due to the deposited metal silver.

An object of the present invention is to solve this problem.

[0015]

In order to achieve the above-mentioned object, the present invention uses a silver ion conductive solid electrolyte containing silver halide-silver oxynate as a main component, and a molded body of the same electrolyte and the same electrolytic molding. A polyester resin is used as a molding binder in an electrode molded body used together with the body. Then, an all-solid-state electrochemical device is constructed by using both the above-mentioned molded bodies.

Further, a linear saturated polyester resin is selected as the polyester resin, and a polyester resin having a glass transition temperature of 50 ° C. or less is selected.

[0017]

There are methods of synthesizing the resin, such as ionic polymerization and solution polymerization. In the case of ionic polymerization, for example, an alkyl metal salt is used as a polymerization catalyst. Many of the alkyl metal salts, such as butyl lithium, have a reducing power, and when such a polymerization catalyst remains in the resin, it has a property of reducing silver oxyacid at a high temperature. On the other hand, polyester resin is less likely to leave a polymerization catalyst as compared with other synthetic rubber resins and exhibits stable properties against silver oxyacid, and is a silver ion composed of silver halide-silver oxyacid. When used as a binder for a conductive solid electrolyte, it exhibits stable properties. Further, the polyester resin has a high binding property with a small mixing ratio, and can be processed into a sheet shape or the like without greatly impairing the ion conductivity, which is preferable.

In the case of the unsaturated polyester resin, the double-bonded portion is three-dimensionally cross-linked at high temperature and hardened, so that the molded product such as a sheet may lose flexibility. Therefore, the polyester resin is preferably a saturated polyester resin.

The branched polyester resin is apt to lose its elastic force by three-dimensionally crosslinking in the course of its polymerization. Therefore, the linear saturated polyester resin is particularly preferable among the saturated polyester resins.

Further, the silver ion conductive solid electrolyte comprising silver halide-silver oxyacid is a solid electrolyte exhibiting high ionic conductivity even at around room temperature, and its operating temperature range is often around room temperature. Therefore, as the polyester resin, those having a glass transition temperature of 50 ° C. or lower are particularly preferable in order to exhibit sufficient flexibility even at room temperature.

[0021]

EXAMPLES The present invention will be described in detail below with reference to examples.

Example 1 As a silver ion conductive solid electrolyte composed of silver halide-silver oxynate, 4AgI-Ag was used.
₂ WO _{4 A} solid electrolyte composed of silver iodide and silver tungstate is used, and polyester resin is a line obtained by randomly copolymerizing dibasic acid such as terephthalic acid and glycol such as ethylene glycol. 300, a silver ion conductive solid electrolyte sheet was prepared by the following method using Byron 300 (manufactured by Toyobo Co., Ltd., molecular weight 20000-25000, glass transition temperature Tg = 7 ° C.) which is a saturated polyester resin.

First, Byron 300, which is a linear saturated polyester resin, was put into toluene and dissolved in an ultrasonic cleaner.

Next, a silver ion conductive solid electrolyte represented by 4AgI-Ag ₂ WO ₄ was synthesized. AgI, Ag
₂ O and WO ₃ were weighed in a molar ratio of 4: 1: 1 and mixed in an alumina mortar. This mixture was pressure-molded into pellets, which were then sealed under reduced pressure in a Pyrex tube and melted and reacted at 400 ° C. for 17 hours. The reaction product was crushed to 200 mesh or less in a mortar and 4AgI · Ag was added.
A silver ion conductive solid electrolyte represented by ₂ WO ₄ was obtained.

The solid electrolyte thus obtained is added to the toluene solution of the polyester resin obtained above in a proportion such that the polyester resin is 2.5% by weight relative to the solid electrolyte, and the mixture is kneaded in a mortar. , A solid electrolyte slurry.

A polyester mesh (200 mesh, thickness 80 μm) was dipped in this solid electrolyte slurry, and the slurry was pulled up from the slurry and the slit width was 15
A squeegee having a thickness of 0 μm was passed through as shown in FIG. However, in FIG. 1, 1 is a polyester mesh, 2 is a solid electrolyte slurry, 3 is a squeegee, 4 is a glass container for storing the slurry, 5 is a roller for pulling up the mesh, and 6 is a guide. Then, toluene was evaporated in the atmosphere to obtain a solid electrolyte sheet.

This solid electrolyte sheet was cut into 10 mmφ, and silver foil was pressed on both sides to form electrodes, and the electrical conductivity (σ) was measured by the AC impedance method. as a result,
The electric conductivity of the solid electrolyte sheet according to this example was σ = 5.2 × 10 ⁻³ S / cm at room temperature.

Next, the electron sustainability of the solid electrolyte sheet according to this example was examined by the Wagner polarization method as follows. The solid electrolyte sheet was cut into 10 mmφ, and a silver foil was pressed on one side and a platinum foil was pressed on the other side to form an electrode. A voltage was applied by a potentiostat so that the platinum electrode became positive, and the current flowing in a steady state was measured. as a result,
The current [I _{(V = 0.5V)} ] flowing at _0.5V is 30nA
Met.

Next, in order to investigate the thermal stability of the solid electrolyte sheet according to this example, it was stored at 100 ° C. for 48 hours. Then, it was cut into 10 mmφ, and its electrical conductivity and electronic insulation were measured by the same method as described above. As a result, the electric conductivity of the solid electrolyte sheet after storage was σ = 4.
It was 9 × 10 ^-3 S / cm, which was almost the same as that before storage, and the electronic insulation measured by the Wagner method was I.
_{(V = 0.5V)} = 30 nA, which was not lowered.

As described above, according to the present invention, it was found that a solid electrolyte sheet which is stable even at high temperature storage can be obtained.

Comparative Example 1 A solid electrolyte sheet was obtained in the same manner as in Example 1 except that a styrene-butadiene block copolymer was used instead of the linear polyester resin (Vylon 300) used in Example 1. It was

The electrical conductivity and electronic insulating property of this solid electrolyte sheet were measured by the same method as in Example 1. The electrical conductivity was σ = 5.5 × 10 ⁻³ S / cm, and the Wagner method was used. The result was also I _{(V = 0.5V)} = 40 nA, which was almost the same as that of the solid electrolyte sheet obtained in Example 1.

In order to investigate the stability of this solid electrolyte sheet at high temperature storage, the same procedure as in Example 1 was performed at 100 ° C. for 4 hours.
An 8-hour storage test was conducted. The electrical conductivity and electronic insulation measured thereafter were σ = 2.3 × 10 ⁻³ S / cm, I
_{Since (V = 0.5V)} = 160 nA, the electric conductivity was lowered and the electronic insulation was also lowered.

(Comparative Example 2) A solid electrolyte sheet was obtained in the same manner as in Example 1 except that polystyrene resin was used instead of the linear polyester resin (Vylon 300) used in Example 1.

The stability of this solid electrolyte sheet in high temperature storage was examined by the same method as in Example 1. As in Comparative Example 1, the high temperature storage showed a decrease in electrical conductivity and a decrease in electronic insulation. It was

Example 2 5 AgI-3A as a silver ion conductive solid electrolyte composed of silver halide-silver oxynate.
A solid electrolyte composed of silver iodide represented by g ₂ O-2V ₂ O ₅ and silver vanadate is used, Vitel PE-200 (manufactured by Goodyear) is used as the linear saturated polyester resin, and a silver ion conductive solid is used. The electrolyte sheet was prepared as follows.

First, V which is a linear saturated polyester resin
Itel PE-200 was put into a solvent mixed with toluene / methyl ethyl ketone = 8: 2, and dissolved in an ultrasonic cleaner.

Next, 5Agl-3Ag ₂ O-2V ₂ O ₅
A silver ion conductive solid electrolyte represented by the following formula was synthesized by the following method.

Ag1, Ag ₂ O and V ₂ O ₅ were weighed so that the molar ratio was 5: 3: 2 and mixed in an alumina mortar. This mixture was reacted with a heating solvent in a glassy carbon crucible, and then the melt was directly poured into liquid nitrogen and quenched. The reaction product obtained as described above was placed in a mortar to
00 ground to a mesh or less, 5Agl-3Ag _{2 O-2}
A silver ion conductive solid electrolyte represented by V ₂ O ₅ was obtained.

The solid electrolyte thus obtained was added to the toluene solution of the polyester resin obtained above in a proportion such that the polyester resin was 5% by weight based on the solid electrolyte, and the mixture was kneaded in a mortar to solid electrolyte. It was made into a slurry.

Using this solid electrolyte slurry, Example 1
A solid electrolyte sheet was obtained in the same manner as.

The electrical conductivity and electronic insulation of this solid electrolyte sheet were measured by the same method as in Example 1. The electrical conductivity was σ = 3.2 × 10 ⁻³ S / cm, and the Wagner method was used. The result was also I _{(V = 0.5V)} = 20 nA.

In order to investigate the stability of this solid electrolyte sheet in high temperature storage, the same procedure as in Example 1 was performed at 100 ° C. for 4 hours.
An 8-hour storage test was conducted. The electrical conductivity and electronic insulation measured thereafter were σ = 3.1 × 10 ⁻³ S / cm, I
_{(V = 0.5V)} = 20 nA, and neither the electrical conductivity nor the electronic insulating property was lowered.

As described above, according to the second embodiment of the present invention,
It was found that a solid electrolyte sheet that is stable even at high temperature storage can be obtained.

Example 3 A silver ion conductive fixed electrolyte sheet was prepared in the same manner as in Example 1 except that the silver ion conductive fixed electrolyte represented by 3AgI-Ag ₄ SiO ₄ was used.

AgI, Ag ₂ O and SiO ₂ were weighed in a molar ratio of 3: 2: 1 and mixed in an alumina mortar. This mixture was heated and melted and reacted in a glassy carbon crucible, and the melt was directly poured into liquid nitrogen and rapidly cooled, and the reaction product was crushed to 200 mesh or less in a mortar and expressed by 3AgI-Ag ₄ SiO ₄ . A silver ion conductive solid electrolyte was obtained.

The electrical conductivity and electronic insulating property before and after high temperature storage were evaluated in the same manner as in Example 1. As a result, it was found that the electrical conductivity and the electronic insulation did not change significantly before and after storage, and according to Example 3 of the present invention, a solid electrolyte sheet was obtained that was stable even at high temperature storage.

Example 4 AgI-Ag ₂ O-2B ₂ O
A silver ion conductive solid electrolyte sheet was prepared in the same manner as in Example 2 except that the silver ion conductive solid electrolyte represented by ₃ was used and the nylon mesh was used instead of the polyester mesh.

First, AgI, Ag₂O, B₂O₃The
The alumina to give a ratio of 1: 1: 2.
Mixed in a mortar. This mixture in a quartz tube at 600 ° C for 1 hour
After melting and reacting for a while, cast it on a stainless steel plate and
Chilled The reaction product obtained as described above is placed in a mortar for 20 minutes.
Crushed to 0 mesh or less and AgI-Ag₂O-2B₂O ₃
A silver ion conductive solid electrolyte represented by the following formula was obtained.

The electric conductivity and the electronic insulating property before and after high temperature storage were evaluated in the same manner as in Example 2. As a result, it was found that the electrical conductivity and the electronic insulation did not change significantly before and after storage, and that according to Example 4 of the present invention, a solid electrolyte sheet that was stable even at high temperature storage was obtained.

(Example 5) A solid electrolyte slurry was prepared in the same manner as in Example 1 except that the mixing ratio of the polyester resin was 8% by weight.

This slurry was applied on a Teflon plate by a doctor blade method to a thickness of 100 μm, and after evaporating the solvent, it was peeled off from the Teflon plate to obtain a silver ion conductive solid electrolytic sheet.

Using this solid electrolyte sheet, the electrical conductivity and electronic insulating property before and after high temperature storage were evaluated in the same manner as in Example 1. As a result, it was found that the electrical conductivity and the electronic insulation did not change significantly before and after storage, and that according to Example 5 of the present invention, a solid electrolyte sheet that was stable even at high temperature storage was obtained.

(Embodiment 6) Byron 290 is used instead of Byron 300 used in Embodiment 1 as a polyester resin.
A silver ion conductive solid electrolyte sheet was prepared in the same manner as in Example 1 except that (manufactured by Toyobo Co., Ltd., glass transition temperature 72 ° C.) was used.

Using this solid electrolyte sheet, the electrical conductivity before and after high temperature storage and the electronic insulation were evaluated in the same manner as in Example 1. As a result, both electric conductivity and electronic insulation did not change significantly before and after storage, and it was found that Example 6 of the present invention provided a solid electrolyte sheet that was stable even at high temperature storage.

Further, the flexibility of this solid electrolyte sheet was tested at room temperature together with the solid electrolyte sheet obtained in Example 1 by a bending test with a radius of 20 mm. As a result, the solid electrolyte sheet obtained in Example 1 did not crack or break, but the solid electrolyte sheet according to this Example did.

Example 7 Ag _0.7 V as an electrode active material
Using a composite oxide composed of silver and vanadium oxide represented by ₂ O ₅ , as a silver ion conductive solid electrolyte composed of silver halide-silver oxyacid, as in Example 1, 4 AgI-
A solid electrolyte composed of silver iodide represented by Ag ₂ WO ₄ and silver tungstate is used, and the polyester resin is
Byron 300 was used in the same manner as in Example 1 to prepare an electrode sheet by the following method.

First, Byron 300, which is a linear saturated polyester resin, was put into toluene and dissolved in an ultrasonic cleaner.

First, a composite oxide of silver and vanadium, which is an electrode active material, was synthesized by the following method. The molar ratio of vanadium oxide represented by V ₂ O ₅ and metallic silver is 1: 0.
Weighed to 7 and mixed in a mortar. Similarly, the mixture was pressure-molded into pellets, and the mixture was vacuum-sealed in a quartz tube.
The mixture was reacted at 600 ° C. for 48 hours and pulverized to 200 mesh or less to obtain a composite oxide composed of silver and vanadium oxide represented by Ag _0.7 V ₂ O ₅ .

The composite oxide thus obtained and the silver ion conductive solid electrolyte obtained in Example 1 were mixed at a weight ratio of 1: 1 to obtain an electrode material.

This electrode material was added to the above-obtained toluene solution of the polyester resin at a ratio such that the polyester resin was 3% by weight with respect to the solid electrolyte, and kneaded in a mortar to obtain a solid electrolyte slurry.

This solid electrolyte slurry was applied to a polyester mesh (200 mesh, thickness 80 μm) in the same manner as in Example 1 to obtain an electrode sheet. The stability of this electrode sheet was evaluated by measuring its electromotive force. The details are shown below.

This electrode sheet was cut to a diameter of 10 mm, pressed against a silver foil via the solid electrolyte sheet obtained in Example 1, and lead terminals were attached to the electrode sheet and the silver foil with a carbon paste to assemble an electrochemical element. Using this electrochemical device, the electromotive force of the electrode sheet was measured as the potential difference between the silver foil and the electrode sheet by an electrometer. As a result, the electromotive force of the electrode sheet according to this example was 11
It was 4 mV.

Next, in order to examine the thermal stability of the electrode sheet according to this example, it was stored at 100 ° C. for 48 hours. After that, it was cut into 10 mmφ and the electromotive force was measured by the same method as described above. As a result, the electromotive force shows 112 mV,
It was found that the electromotive force of the electrode sheet according to Example 7 of the present invention did not change even at high temperature storage.

As described above, according to the seventh embodiment of the present invention,
It was found that an electrode sheet that is stable even at high temperature storage can be obtained.

Comparative Example 3 An electrode sheet was obtained in the same manner as in Example 7 except that a styrene-butadiene block copolymer was used instead of the linear polyester resin (Vylon 300) used in Example 7. ..

When the electromotive force of this electrode sheet was measured by the same method as in Example 7, it was 110 mV.

In order to investigate the stability of this solid electrolyte sheet in high temperature storage, the same procedure as in Example 7 was conducted at 100 ° C. for 4 hours.
An 8-hour storage test was conducted. The electromotive force of the electrode sheet measured thereafter showed a low value of 86 mV, and it was found that the electrode sheet in this comparative example was not stable upon storage at high temperatures.

Example 8 Ag _0.8 V as an electrode active material
_A composite oxide composed of silver and vanadium oxide represented by ₂ O ₅ was used, and as a silver ion conductive solid electrolyte composed of silver halide-silver oxyacid, as in Example 2, 5 AgI-
Using a solid electrolyte represented by 3Ag ₂ O-2V ₂ O ₅ ,
As the polyester resin, as in Example 2, Vite
An electrode sheet was prepared in the same manner as in Example 7 by using PE-200.

However, Ag _0.8 V ₂ O which is an electrode active material
₅ was synthesized in the same manner as in Example 7, except that vanadium oxide represented by V ₂ O _{5 as} a starting material and metallic silver were mixed at a molar ratio of 1: 0.8. The ratio of the polyester resin to the electrode material was 3.5% by weight.

The stability of this electrode sheet was evaluated by measuring its electromotive force in the same manner as in Example 7. As a result, the electromotive force before storage was 70 mV and 69 m after storage.
It was almost unchanged from V.

As described above, according to the eighth embodiment of the present invention,
It was found that an electrode sheet that is stable even at high temperature storage can be obtained.

Example 9 A composite oxide composed of Ag _0.7 V ₂ O ₅ represented by Ag 7 V ₂ O ₅ and vanadium oxide obtained in Example 7 was used as an electrode active material, and silver halide-silver oxynate was used. As the silver ion conductive solid electrolyte, a solid electrolyte composed of silver iodide and silver tungstate represented by 4AgI-Ag ₂ WO ₄ was used as in the case of Example 1, and as the polyester resin, byron was used as in the case of Example 1. 300 was used to prepare an all-solid-state secondary battery as an all-solid-state electrochemical device by the following method.

First, a silver ion conductive solid electrolyte sheet was prepared in the same manner as in Example 1. Then, an electrode sheet was obtained in the same manner as in Example 7. However, in that case, the slit interval of the squeegee 3 in FIG. 1 was adjusted to prepare an electrode sheet having a thickness of 100 μm and a thickness of 200 μm.

These two kinds of electrode sheets were thermocompression-bonded to both surfaces of the solid electrolyte sheet, cut into 10 mm × 10 mm, and the lead terminals were adhered with silver paste to obtain an all-solid secondary battery. This sectional view is shown in FIG. In the figure, 7 is 100 μ thick
m is a positive electrode sheet, and 8 is a negative electrode sheet having a thickness of 200 μm. Reference numeral 9 is a solid electrolyte sheet, 10 and 11 are carbon pastes that are current collectors, and 12 and 13 are lead terminals.

Using this all-solid secondary battery, 250 mV
To 500 mV constant current charge / discharge test was performed. As a result, the charge / discharge efficiency was almost 100%, and the discharge capacity was 43%.
It was 0 μA · hr.

Next, in order to examine the thermal stability of the all solid state secondary battery according to this example, it was stored at 100 ° C. for 48 hours. Then, when the same charge and discharge test as above was performed,
Charge / discharge efficiency is almost 100%, discharge capacity is 420μ
It was A · hr, and showed performance equivalent to that before storage at high temperature. Further, when charging and discharging were repeated, there was no deterioration in characteristics even after 500 cycles.

As described above, according to the ninth embodiment of the present invention,
It was found that an all-solid-state electrochemical device that is stable even at high temperature storage can be obtained.

(Comparative Example 4) Using the solid electrolyte sheet obtained in Comparative Example 1 and the electrode sheet obtained in Comparative Example 3, Example 9 was used.
An all-solid-state secondary battery was prepared as an all-solid-state electrochemical device in the same manner as in. Using this all-solid-state secondary battery, stability in high temperature storage was evaluated in the same manner as in Example 9.

As a result, before high-temperature storage, the charge / discharge efficiency was almost 100% and the discharge capacity was 420 μA · hr, which was almost the same as that of Example 9. However, after high temperature storage, the charge / discharge efficiency was 93%, and the discharge capacity was 380 μA, which were all decreased. Further, the charge / discharge efficiency decreased as the charge / discharge was repeated thereafter. When the battery was disassembled and the cause thereof was investigated, deposition of metallic silver was observed on the negative electrode, and it was found that the electrolyte reacted with the resin to produce metallic silver.

Example 10 Example 7 as electrode active material
Using a composite oxide composed of Ag _0.7 V ₂ O ₅ represented by Ag _0.7 V ₂ O ₅ consisting of silver and vanadium oxide, as a silver ion conductive solid electrolyte composed of silver halide-silver oxyacid, as in Example 2, 5 AgI -3Ag ₂ O-2V ₂ O ₅ with 4AgI-
A silver ion conductive solid electrolyte represented by Ag ₂ WO ₄ was used, a linear saturated polyester resin was used as the polyester resin in the same manner as in Example 1, and an all-solid secondary battery was used as an all-solid electrochemical element as follows. I made it like this.

First, a silver ion conductive solid electrolyte sheet was prepared in the same manner as in Example 1. The electrode slurry obtained in Example 7 was applied to one surface of this solid electrolyte sheet by screen printing to a thickness of 50 μm to form a positive electrode layer. Subsequently, the other side of the solid electrolyte sheet was coated with the electrode slurry obtained in Example 7 to a thickness of 100 μm by a screen printing method to form a negative electrode layer. The solid electrolyte sheet having electrodes formed on both sides in this way was dried under reduced pressure to remove the solvent, and the electrodes were coated with carbon paste to obtain a current collector. Further, this solid electrolyte sheet was cut into a size of 7 mm × 7 mm, and lead terminals were bonded with a carbon paste to obtain an all solid state secondary battery. However, the electrode slurry having a thickness of 50 μm was printed as a positive electrode, and the electrode slurry having a thickness of 100 μm was used as a negative electrode.

Using this all-solid-state secondary battery, 250 mV
To 500 mV constant current charge / discharge test was performed. As a result, the charge / discharge efficiency was almost 100%, and the discharge capacity was 11%.
It was 0 μA · hr.

Next, in order to examine the thermal stability of the all-solid secondary battery according to this example, it was stored at 100 ° C. for 48 hours.
After that, when the same charge / discharge test as above was performed, the charge / discharge efficiency was almost 100%, and the discharge capacity was 110 μA.
It was hr and showed the same performance as that before storage at high temperature. Also,
When charging and discharging were repeated, there was no deterioration in characteristics even after 500 cycles.

As described above, according to Example 10 of the present invention, it was found that an all-solid-state electrochemical device which is stable even at high temperature storage can be obtained.

Example 11 Example 7 as an electrode active material
Using a composite oxide of Ag _0.7 V ₂ O ₅ represented by Ag _0.7 V ₂ O ₅ composed of silver and vanadium oxide as a silver ion conductive solid electrolyte of silver halide-silver oxyacid oxide, 4 AgI -A solid electrolyte composed of silver iodide represented by Ag ₂ WO ₄ and silver dungstate is used, the polyester resin is Vylon 300 as in Example 1, and an all-solid secondary battery is used as an all-solid electrochemical device. Was created by the following method.

First, a silver ion conductive solid electrolyte sheet was prepared in the same manner as in Example 1. Next, an electrode sheet was obtained in the same manner as in Example 7. However, in that case, the slit interval of the squeegee 3 in FIG. 1 was adjusted to prepare an electrode sheet having a thickness of 100 μm and a thickness of 200 μm.

The two types of electrode sheets were thermocompression bonded to both sides of the solid electrolyte sheet, cut into 10 mm × 10 mm, and the lead terminals were adhered with silver paste to obtain an all solid state secondary battery.
This sectional view is the same as the structure shown in FIG. 2 in the ninth embodiment.

Using this all-solid-state secondary battery, 250 mV
To 500 mV constant current charge / discharge test was performed. As a result, the charge / discharge efficiency was almost 100%, and the discharge capacity was 43%.
It was 0 μA · hr.

Next, in order to investigate the thermal stability of the all solid state secondary battery according to this example, it was stored at 100 ° C. for 48 hours.
After that, when the same charge / discharge test as above was performed, the charge / discharge efficiency was almost 100%, and the discharge capacity was 420 μA.
It was hr and showed the same performance as that before storage at high temperature. Also,
When charging and discharging were repeated, there was no deterioration in characteristics even after 500 cycles.

As described above, according to Example 11 of the present invention, it was found that an all-solid-state electrochemical device which is stable even at high temperature storage can be obtained.

Example 12 Example 7 as an electrode active material
Using a composite oxide of Ag _0.7 V ₂ O ₅ represented by Ag _0.7 V ₂ O ₅ composed of silver and vanadium oxide as a silver ion conductive solid electrolyte of silver halide-silver oxyacid oxide, 4 AgI -A solid electrolyte composed of silver iodide represented by Ag ₂ WO ₄ and silver dungstate is used, as the polyester resin, Vylon 300 is used as in Example 1, and an electrochemical actuator is used as an all-solid-state electrochemical device. Was created by the following method.

First, the solid electrolyte slurry obtained in Example 1 and the electrode slurry obtained in Example 7 were heated to 70 ° C. under reduced pressure to evaporate the solvent. 200 mg of the mixture of the solid electrolyte and the polyester resin and 200 mg of the mixture of the electrode material and the polyester resin were weighed, and the electrode material /
The solid electrolyte / electrode material was pressure-molded into a pellet having a three-layer structure. Lead terminals were bonded to both ends of this pellet with a carbon paste to form an electrochemical actuator.

In this electrochemical actuator, ± 1 mA
A constant current pulse for 1 minute was applied with the current value of, and the change in the length of the actuator at that time was measured using a laser displacement meter. As a result, with the application of the constant current pulse, ± 0.
A displacement of 6 μm was observed.

Next, in order to examine the thermal stability of the all-solid secondary battery according to this example, it was stored at 100 ° C. for 48 hours. After that, when an operation test similar to the above was conducted, there was no significant change from that before storage, and no change appeared in the characteristics after 1000 cycles of operation.

As described above, according to the present invention, it was found that an all-solid-state electrochemical device which is stable even at high temperature storage can be obtained.

Comparative Example 5 The solid electrolyte slurry and the electrode slurry used in Example 12 were replaced with the solid electrolyte slurry obtained in Comparative Example 1 and the electrode slurry obtained in Comparative Example 3, respectively. An electrochemical actuator was produced as an all-solid-state electrochemical device in the same manner as in Example 12. Using this electrochemical actuator, stability in high temperature storage was evaluated in the same manner as in Example 12.

As a result, the actuator in this comparative example showed substantially the same characteristics as in Example 12 before the high temperature storage, but became inoperable after 230 cycles in the operation cycle after the high temperature storage. When the actuator was disassembled and the cause was investigated, metal silver deposition was found on the negative electrode, and it was found that there was separation between the negative electrode and the electrolyte, and it was found that the reaction of the electrolyte with the resin produced metal silver. It was

In the examples of the present invention, halogen is used.
As a silver ion-conducting solid electrolyte of silver oxide-silver oxyacid system,
4AgI-Ag₂WO_Four, 5AgI-3Ag₂O-2V
₂O _Five, 3AgI-Ag_FourSiO_Four, AgI-Ag₂O
-2B₂O₃Silver ion conductive solid electrolyte represented by
I explained about the solid electrolytic
With different quality composition ratios, AgI-Ag₂O-MoO₃
Other transfer metal oxides or those containing silver oxygenate, or
AgI-Ag₂O-WO₃-B₂O₃4 component system such as
Of AgCI-Ag₂WO_FourHalogen other than silver iodide
Similar effects can be obtained with silver halide
Needless to say, the present invention includes the solids listed in these examples.
It is not limited to the electrolyte.

In the examples of the present invention, an example in which a composite oxide composed of silver and vanadium oxide represented by Ag _0.7 V ₂ O ₅ or Ag _0.8 V ₂ O ₅ is used as an electrode active material will be described. It was carried out, but further, a complex oxide having a different silver ion concentration, silver selenide, silver selenide-
It goes without saying that similar effects can be obtained with other active materials such as silver phosphate solid solution, niobium disulfide, iodine complex, and metallic silver that act as active materials with respect to the silver ion conductive solid electrolyte. Is not limited to the electrode active materials listed in these examples.

In the embodiments of the present invention, the all-solid-state electrochemical device is described by taking an all-solid secondary battery or an electrochemical actuator as an example. However, other all-solid-state electrochemical devices such as coulometers and sensors are used. Needless to say, the same effects can be obtained for the devices, and the present invention is not limited to the all-solid-state electrochemical devices described in these examples.

Further, in the embodiment of the present invention, polyester resin and Byron 300, Vitel PE-200 are used.
As an example, explanations are given, but byron 200 (manufactured by Toyobo), Vitel PE-207 (manufactured by Goodyear), du Pont Adhesive 46950.
Needless to say, the same effect can be obtained with other polyester resins (manufactured by DuPont) and the like, and the present invention is not limited to the all-solid-state electrochemical elements described in these examples.

[0103]

As described above, according to the present invention, a silver ion conductive solid electrolyte molded body which is stable even at high temperature, for example, a sheet-shaped molded body, an electrode molded body used together with the molded body, and an all solid body using both molded bodies. An electrochemical device could be obtained.

As the polyester resin, a linear saturated polyester resin is more preferable, and one having a glass transition temperature of 50 ° C. or lower is more preferable.

[Brief description of drawings]

FIG. 1 Principle diagram of a solid electrolyte sheet producing apparatus

FIG. 2 is a sectional view of an all solid state secondary battery according to an embodiment of the present invention.

[Explanation of symbols]

 1 Polyester Mesh 2 Solid Electrolyte Slurry 3 Squeegee 4 Glass Container 5 Roller 6 Guide 7 Positive Electrode Sheet 8 Negative Electrode Sheet 9 Solid Electrolyte Sheet 10, 11 Current Collector 12, 13 Lead Terminal

Claims (12)

[Claims] 1. A solid electrolyte molded body containing a silver ion conductive solid electrolyte mainly composed of silver halide-silver oxyacid and a polyester resin. 2. A silver halide in claim 1 - oxygen silver are represented by the general formula _{aAgX-bAg 2 O-cM m1} O n1, wherein X is I, Br, 1 kind selected from Cl or Two or more kinds of halogen elements, M is W, Mo, S
A solid electrolyte molded body which is one or more elements selected from the group consisting of i, V, Cr, P and B, and a, b, c, m ₁ and n ₁ are substances showing respective coefficients. .. 3. A silver halide in claim 1 - oxygen silver are represented by the general formula pAgX-qAgM _m2 O _2, wherein X
Is one or more kinds of halogen elements selected from I, Br and Cl, and M is W, Mo, Si, V and C
A solid electrolyte molded body, which is one or more elements selected from the group consisting of r, P, and B, and P, q, and m ₂ are substances each showing a coefficient. 4. The solid electrolyte molded body according to claim 1, wherein the polyester resin is a linear saturated polyester resin. 5. The solid electrolyte molded body according to claim 1, wherein the polyester resin has a glass transition temperature of 50 ° C. or lower. 6. An electrode active material which is combined with a solid electrolyte molded body containing a silver ion conductive solid electrolyte mainly composed of silver halide-silver oxyacid and a polyester resin, and which acts as an active material on the solid electrolyte. And an electrode molded body containing a polyester resin. 7. The electrode molded body according to claim 6, wherein the electrode active material is a material mainly composed of a composite oxide of silver oxide and another metal oxide. 8. The polyester resin in the solid electrolyte and / or the polyester resin in the electrode molded body is a linear saturated polyester resin.
The electrode molding described. 9. The glass transition temperature of the polyester resin in the solid electrolyte and / or one or both of the polyester resins in the electrode molded body is 50 ° C. or lower.
8. The electrode molded body according to any one of 8. 10. A solid electrolyte molded body containing a silver ion conductive solid electrolyte mainly composed of silver halide-silver oxyacid and a polyester resin, and an electrode active material and a polyester resin which act as an active material for the electrolyte. An all-solid-state electrochemical device provided with both an electrode molded body having and. 11. The polyester resin in the solid electrolyte molded body and one or both of the polyester resins in the electrode molded body are linear saturated polyester resins.
The all-solid-state electrochemical device described. 12. The all-solid-state electricity according to claim 10, wherein one or both of the polyester resin in the solid electrolyte molded body and the polyester resin in the electrode molded body has a glass transition temperature of 50 ° C. or lower. Chemical element.