JPH09134739A - Solid electrolyte and battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid electrolyte which has aromatic polyamide and an electrolyte for its main components, and is excellent in heat resistance and mechanical strength, and can be used as a battery, an electrochromic element, or an electrochemical sensor. SOLUTION: A solid electrolyte has an aromatic polyamide and an electrolyte for its main components. The total content of the aromatic polyamide within the solid electrolyte and the electrolyte is larger than 85wt.%, and besides the content of the electrolyte within the solid electrolyte is in the range of 10-90wt.%. The used aromatic polyamide is high in heat resistance, and beside is excellent in mechanical property, so the thinning is possible, and further this solid electrolyte is excellent in ion conductivity, containing electrolyte in high concentration. By using this solid electrolyte, a safe battery which prevents the short circuit of the electrode caused by the dissolution of the material attendant upon temperature rise, the gushing of electrolyte or the decomposed gas, etc., can be obtained.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a solid electrolyte having excellent heat resistance and mechanical properties, which is useful as an ion transfer medium in the fields of electrochemistry such as batteries, electrochromic devices and electrochemical sensors.

[0002]

2. Description of the Related Art Conventionally, in an alkaline secondary battery or a lithium secondary battery, a non-woven fabric made of a polyolefin material such as polypropylene or polyethylene or a separator made of a microporous membrane is impregnated with an electrolytic solution. Further, attempts to use an aromatic polyamide as a porous separator excellent in heat resistance and the like are disclosed in JP-A-58-147956, JP-A-5-290822, and JP-A-5-335005.

On the other hand, as an attempt to use a solid electrolyte made of a polymer material instead of the porous separator, P.
W. Wright reported alkali metal salt complexes of polyethylene oxide in 1975, British, Polymers, Journal, Volume 7, p. 319,
Since then, a wide range of studies for practical application of polyethylene oxide-based solid electrolytes have been conducted.

Further, a gel-like solid electrolyte obtained by adding an electrolyte and a solvent to a matrix polymer as a support having no ion conductivity such as polyether sulfone and polyparabanic acid is disclosed in JP-A-1-309205, It has been proposed in Kaihei 2-86558, JP-A-3-37268, and the like.

[0005]

A battery using a conventional polyolefin-based porous separator impregnated with an electrolytic solution has a problem in mechanical properties or inferior heat resistance.
There is a problem that a minute short circuit occurs and the heat generated thereby melts the separator, causing a large short circuit and further intense heat generation. Further, if the battery is forcibly heated, there is a risk that the electrolytic solution may be ejected from the battery container or the decomposition gas of the electrolytic solution may be ejected.

On the other hand, the polymer solid electrolyte has a problem that its ionic conductivity is inferior to that of the liquid electrolyte. Therefore, in order to obtain high ionic conductivity, a gel containing a large amount of electrolytic solution in the polymer electrolyte is used. Substances have been proposed. Since these solid electrolytes contain a large amount of electrolytic solution, they have the same problem of solvent origin as batteries using a porous separator.

Another problem is that many polyethylene oxide-based polymer solid electrolytes have a low glass transition point, undergo a large morphological change under heating and have poor heat resistance. In addition, in order to improve the battery characteristics, it is necessary to reduce the thickness in order to reduce the resistance, and the mechanical strength of the solid polymer electrolyte corresponding to this is required, but so far. There is no material that has both high ionic conductivity and high mechanical strength.

On the other hand, in the case of a porous separator using a heat-resistant aromatic polyamide, a method of welding a laminate of fibers or a fibrillar pulp-like material has been adopted. However, the aromatic polyamide has a problem that it is difficult to weld and it is difficult to process it into a desired form.

[0009]

Therefore, the present inventors have solved the problems of such a porous separator / electrolyte system and conventional polymer solid electrolytes, and have high ionic conductivity, high stability, and high stability. We have conducted intensive studies to develop a new solid electrolyte that has both mechanical strength and processability. As a result, the present inventors have found that the aromatic polyamide shows a good affinity with various electrolytes, and can contain a large amount of electrolyte while maintaining the uniformity of the membrane, and further, the composition is excellent as a solid electrolyte. The present invention has been completed by confirming that the above characteristics are exhibited.

That is, the first aspect of the present invention is a solid electrolyte mainly composed of an aromatic polyamide and an electrolyte, wherein the total content of the aromatic polyamide and the electrolyte in the solid electrolyte is more than 85% by weight, Further, the solid electrolyte is characterized in that the content of the electrolyte in the solid electrolyte is in the range of 10 to 90% by weight.

The aromatic polyamide used in the solid electrolyte of the present invention (1) has high heat resistance, and (2) has excellent mechanical properties, so that it can be formed into a thin film and further contains the electrolyte in a high concentration. It is possible to provide a solid electrolyte having excellent ionic conductivity. By using the solid electrolyte of the present invention, when the temperature of the battery rises for some reason, a short circuit of the electrode due to melting of the material and a safe battery that prevents the ejection of the electrolytic solution or its decomposition gas can be achieved. It is possible to provide.

The aromatic polyamide which is the composition of the present invention is a polymer having an aromatic ring and an amide bond, and has excellent heat resistance and mechanical strength. A polyamide formed by combining a unit selected from the group consisting of as the main constituent unit.

[0013]

Embedded image --NH--Ar ₁ --NH--

[0014]

Embedded image --CO--Ar ₂ --CO--

[0015]

Embedded image —CO—Ar ₃ —NH—

Here, Ar ₁ , Ar ₂ and Ar ₃ each represent a divalent group having an aromatic ring structure or a structure in which a plurality of aromatic rings are connected. Further, the carbon number in Ar ₁ , Ar ₂ , and Ar ₃ is 6 to 2
The range is 0, preferably 6 to 15, and particularly preferably 6 to 12 or 6. Ar ₁ , Ar ₂ , A
r ₃ may be the same or different, and typical examples thereof include the following.

[0017]

Embedded image

[0018]

Embedded image

[0019]

[Chemical 6]

[0020]

Embedded image

The following is given as an example of the chemical formula 7.

[0022]

Embedded image

[0023]

Embedded image

Further, some of the hydrogens on these aromatic rings are
Those substituted with a halogen atom such as a chlorine atom or a fluorine atom, a nitro group, a lower alkyl group, a lower alkoxy group or the like are also included in Ar ₁ , Ar ₂ and Ar ₃ . X is -O-,
_{-CH 2 -, - SO 2 -} , - S -, - CO -, - C (C
_{H 3) 2 -, - C} (CF 3) 2 - is a divalent linking group such as. Further, a methylene unit, a pyridylene unit or a unit such as ester, urethane, urea, ether or thioether may be copolymerized as a constitutional unit in a small amount so long as the constitutional requirements of the present invention and the action and effect are not impaired.

Specific examples of the aromatic polyamide used in the present invention are rigid molecular chains as disclosed in, for example, JP-A-62-174118 and JP-A-62-174129. Examples include polyparaphenylene terephthalamide (hereinafter abbreviated as PPTA). A film made of this polymer is completely non-oriented in a hygroscopic state before drying, but has a melting point of 550 ° C. or higher and a tensile strength of 450 MPa after drying, which is a preferable material for use in the present invention. Such an aromatic polyamide can be produced, for example, by using the monomers aromatic dicarboxylic acid or aromatic dicarboxylic acid chloride and aromatic diamine as raw materials, and by the low temperature solution polymerization method described in US Pat. No. 4,308,374.

As the electrolyte used in the present invention, an ionic dissociative inorganic salt, organic salt, inorganic acid or organic acid can be used, and any electrolyte can be selected according to the application. For example, LiPF ₆ , LiAsF
₆ , Li ₂ CO ₃ , LiBF ₄ , LiClO ₄ , LiC
1, CF ₃ SO ₃ Li, CF ₃ CF ₂ CF ₂ SO ₃ L
i, LiNO ₃ , CH ₃ CO ₂ Li, LiF, LiN
[SO ₂ CF ₃ ] ₂ , LiC [SO ₂ CF ₃ ] ₃ , Na
I, KCl, Et ₄ NClO ₄ , CF ₃ SO ₃ H, H ₂
A monovalent electrolyte such as SO ₄ or a polyvalent electrolyte, or a polymer electrolyte such as a fluorinated polysulfonic acid or a lithium salt thereof may be used alone or in combination.

As the solid electrolyte for the lithium battery, various lithium salts in the above electrolyte are used. Further, it is also possible to use Li ₃ N or various ceramics-based solid electrolytes alone or in combination with the above-mentioned various electrolytes and add them to the aromatic polyamide.

The total content of the aromatic polyamide and the electrolyte in the solid electrolyte of the present invention is 85 based on the total weight of the solid electrolyte.
More than 8 wt%, preferably more than 88 wt% or 9
It is 2% by weight or more, particularly preferably 97% by weight or more.

The solid electrolyte of the present invention may consist essentially of an aromatic polyamide and an electrolyte, and does not necessarily require a plasticizer. That is, the solid electrolyte of the present invention is problematic in terms of safety (for example, flammability of the plasticizer, generation of gas due to decomposition of the plasticizer, generation of lithium metal dendrite in the case of a lithium secondary battery). A major feature is that basically plasticizers do not have to be used. However, a small amount of a plasticizer may be added to the solid electrolyte of the present invention for the purpose of improving processability, adjusting mechanical properties, or improving ionic dissociation so long as the characteristics of the solid electrolyte of the present invention are not impaired. . In the solid electrolyte of the present invention, the plasticizer is used in an amount of 1 relative to the total amount of the solid electrolyte.
It may be contained in an amount of less than 5% by weight, preferably less than 12% by weight or less than 8% by weight, particularly preferably less than 3% by weight. On the other hand, if the content of the plasticizer is 15% by weight or more, the above-mentioned safety problem derived from the plasticizer becomes remarkable, which is not preferable.

The content of the electrolyte in the solid electrolyte of the present invention is
A range of 10 to 90% by weight based on the total weight of the solid electrolyte,
It is preferably in the range of 20 to 80% by weight, particularly preferably 3
It is in the range of 0 to 70% by weight. If the electrolyte content is less than 10% by weight, sufficient ionic conductivity cannot be obtained,
On the other hand, if it is higher than 90% by weight, sufficient mechanical strength cannot be obtained, which is not preferable. For the same reason, the range of the electrolyte / aromatic polyamide weight ratio in the solid electrolyte of the present invention is selected as follows. That is, the lower limit of the weight ratio is 10/90, preferably 20/8.
0, particularly preferably 30/70. The upper limit of the weight ratio is 90/10, preferably 80/20, particularly preferably 70/30.

The plasticizer added to the solid polymer electrolyte of the present invention includes cyclic carbonate compounds such as ethylene carbonate, propylene carbonate and butylene carbonate, and chain carbonate compounds such as dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate. Ether compounds such as tetrahydrofuran, methyltetrahydrofuran, dimethoxyethane, crown ether, butyl lactone, propiolactone,
Ester compounds such as methyl acetate, nitrile compounds such as acetonitrile and propionitrile,

Low molecular weight organic compounds such as various hydrocarbon compounds; oligoethylene oxide, polyethylene oxide,
Aliphatic polyethers such as polypropylene oxide; Solvent-soluble fluoropolymers such as polyvinylidene fluoride and poly (vinylidene fluoride / hexafluoropropylene) copolymers; polar such as polyacrylonitrile, aliphatic polyester, and aliphatic polycarbonate Group-containing polymer plasticizers can be mentioned. From the aromatic polyamide, the electrolyte, and the plasticizer described above, constituent elements are selected according to the intended use to form a solid electrolyte. If necessary, other polymers and ceramics can be added to adjust the mechanical strength and heat resistance.

The solid electrolyte of the present invention has a structure in which the electrolyte is uniformly dispersed in an aromatic polyamide, and the solid electrolyte as a whole has ionic conductivity, and the voids of a porous separator having no ionic conductivity. It is fundamentally different from what is impregnated with a solution in which an electrolyte is dissolved. Therefore, the solid electrolyte of the present invention has low gas and liquid permeability,
It has a property of effectively transmitting ions.

The solid electrolyte of the present invention uses an aromatic polyamide having excellent heat resistance and contains only a small amount of a plasticizer, and therefore has excellent mechanical properties and heat resistance, and contains a large amount of conventional plasticizers. In a wider temperature range compared to swelling gel-based polymer solid electrolytes and microporous membrane separators,
Its form and performance are maintained.

In particular, when polyparaphenylene terephthalamide is used as the aromatic polyamide, the melting point of the film is 550 ° C. or higher, and even at 200 ° C. or higher, it hardly shows deformation such as shrinkage. Compared to the thermal decomposition temperature of polyethylene oxide of about 330 ° C, which has been studied for practical application as a polymer solid electrolyte, the thermal decomposition temperature of aromatic polyamide is 400 ° C or higher, which is extremely stable. It is excellent in

The method for producing the solid electrolyte of the present invention is not particularly limited, and any production method suitable for the combination of the aromatic polyamide and the electrolyte used may be employed. That is, a method of film-forming an aromatic polyamide, a cleaning solution such as a solvent or water used for film formation, a method of replacing with a solution prepared by dissolving an electrolyte in a suitable solvent and then drying, or an aromatic polyamide, a molding containing an electrolyte. A method of performing film forming after dissolving in a solvent and then drying, or a method of forming a film of aromatic polyamide, impregnating with a solution in which an electrolyte is dissolved after drying, and then drying again is optionally used. .

For example, when using PPTA as disclosed in JP-A-62-174118 and JP-A-62-174129, after dissolving PPTA in a solvent such as concentrated sulfuric acid to form a film, Coagulate and wash. Then, the film is dried after impregnating it with an aqueous solution of an electrolyte in a wet state. Alternatively, Japanese Examined Japanese Patent Publication Sho 56-4
As disclosed in Japanese Patent No. 5421, in the case of a halogen-substituted aromatic polyamide soluble in an organic solvent, the target solid electrolyte is obtained by dissolving the aromatic polyamide in an electrolyte solution, forming a film, and then drying the film. Can be manufactured. As a drying method, an arbitrary method is adopted depending on the solvent.

The solid electrolyte produced by adding a plasticizer during or after the production process may contain less than 15% of the above plasticizer. Further, the presence of a small amount of impurities, such as water or low molecular weight organic compounds, which are mixed in during the production process of the solid electrolyte, etc., is allowed within a range that does not affect the heat resistance and mechanical resistance of the solid electrolyte.

The second aspect of the present invention is a battery using the solid electrolyte. For example, explaining an electrode configuration example when applied to a lithium battery, as the negative electrode used,
Metal lithium, aluminum / lithium alloy, magnesium /
Lithium alloys such as aluminum-lithium alloy, Li _x M _y
Solid solutions of lithium and metal oxides represented by O ₂ such as titanium oxide and iron oxide, carbon materials such as graphite, coke, and low temperature calcined polymers, and simple substances and mixtures of carbon such as them, and further these materials A composite material in which powder is bound with a binder such as a polymer or metal particles can be used.

As the positive electrode, a transition metal oxide, a transition metal sulfide, a transition metal halide, and a solid solution of them and lithium, which have a higher electric potential than the above-mentioned negative electrode,
Organic compounds or mixtures thereof can be mentioned.

For example, as an example of the transition metal oxide, L
iCoO ₂ , LiNiO ₂ , Li ₂ MnO ₃ , LiNi
_1-x Co _x O ₂ , LiNi _1-x Mg _x O ₂ , LiNi
_1-x Al _x O ₂ , LiMn ₂ O ₄ , Li ₂ Mn ₂ O ₄ ,
Li ₆ MnO ₄ , LiTi ₂ O ₄ , LiV ₂ O ₄ , Li
₄ Ti ₅ O ₁₂ or the like, a mixture thereof, a solid solution, or the like can be given. Also, mixtures of these with other inorganic salts such as V _x
O _y P ₂ O ₅ or the like is also used.

Examples of transition metal sulfides include MoS ₂ ,
TiS _{2 and the} like can be mentioned. Examples of transition metal halides include FeCl ₃ , FeBr ₃ , FeF _{3 and the} like. Further, a composite material obtained by binding powders of these metal compounds with an organic binder can also be used as the electrode. It is also possible to use an organic compound positive electrode material such as a disulfide / thiolate compound, mercaptan, polyaniline, polythiophene, polypyrrole, or a simple substance or a mixture thereof. In addition, a current collector made of a metal material can be provided on the electrode in order to carry out current transfer between the electrode material and the electrode terminal in the electrode.

The battery according to the present invention is
It can take any form, and the battery using the solid electrolyte is not limited to the above. In the battery of the present invention, since the electrolyte is uniformly dispersed in the solid electrolyte, voids do not exist, and short-circuiting of electrodes due to growth of metal crystals on the surface of the current collector does not occur. Further, since the plasticizer is not contained or only contained in a small amount, the solvent or its decomposed gas does not spout from the battery container due to heat generation due to a short circuit or the like. For this reason, not only is the performance less deteriorated over a long period of time, but also long-term safety can be maintained. Further, the electrochemical element may be used for a battery, an electrochromic element, an electrochemical sensor and the like.

[0044]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described in more detail with reference to Examples.

[0045]

【Example】

Example 1 Anhydrous lithium chloride was dissolved in N-methylpyrrolidone, and then paraphenylenediamine was dissolved therein. Further, terephthalic acid dichloride was added to obtain a PPTA polymer.
This PPTA polymer was dissolved in sulfuric acid having a concentration of 99.7% and cast from a die onto an endless belt. After heating and moisture absorption on the belt, the concentration at 0 ° C is 40%
Coagulated in sulfuric acid, washed with water, neutralized, washed with water, and then wound up to obtain a water swollen PPTA film. This PPT
The A film (film thickness: 197 μm) was immersed in a 4M lithium trifluoromethanesulfonate aqueous solution for 3 days, and then dried under vacuum at 100 ° C. for 5 hours to obtain a light yellow transparent solid electrolyte having a film thickness of 100 μm.

As a result of elemental analysis, it was found that the lithium trifluoromethanesulfonate salt was contained in an amount of about 50% by weight, and the total content of the PPTA polymer and lithium trifluoromethanesulfonate was 99% by weight or more.
This was also confirmed by thermogravimetric analysis, in which the weight loss due to temperature rise up to 300 ° C. was 1 wt% or less. In addition, it was confirmed that no diffraction peaks other than the broad diffraction peaks derived from the polymer were observed in the powder X-rays, and that the sulfur atoms were uniformly dispersed by energy dispersive X-ray spectroscopy. In, it was confirmed that the lithium salt was uniformly dispersed.

The obtained solid electrolyte was sandwiched between stainless sheets and impedance measurement was performed (EG & G, 389 type impedance meter). As a result, room temperature ionic conductivity was 8 × 10 ^-6 S / cm. Further, as a result of thermogravimetric analysis and differential thermal analysis in a nitrogen stream, no exothermic absorption peak was observed below 300 ° C.

Example 2 A PPTA film (film thickness: 197 μm) wet with water was applied to
After being dipped in an aqueous solution of M tetrafluoroborate for 3 days, it is dried under vacuum at 100 ° C. for 5 hours to give a film thickness of 100 μm.
Of solid electrolyte was obtained. Elemental analysis of this solid electrolyte revealed that it contained 30 wt% lithium tetrafluoroborate, and the total content of PPTA polymer and lithium tetrafluoroborate was 99 wt% or more. The obtained solid electrolyte was sandwiched between stainless sheets and impedance measurement was performed. As a result, room temperature ionic conductivity was 1 × 10 ⁻⁵ S / cm.

Example 3 A dry PPTA film (film thickness: 4 μm) was added to a solution of 2M lithium hexafluorophosphate in a mixed solvent of dimethyl carbonate and ethylene carbonate (mixing ratio 1: 1).
After immersion for 3 days at a temperature of 0 ° C. and vacuum drying at room temperature for 6 hours, a solid electrolyte having a film thickness of 10 μm was obtained.
As a result of elemental analysis of this solid electrolyte, it was found to contain 20 wt% of lithium hexafluorophosphate. Further, as a result of thermogravimetric analysis, it was found that 8 wt% of ethylene carbonate was contained. In addition, the solid electrolyte PP
The total content of TA polymer and lithium hexafluorophosphate was about 90 wt%. The obtained solid electrolyte was sandwiched between stainless sheets and impedance measurement was performed. As a result, room temperature ionic conductivity was 3 × 10 ⁻⁵ S / cm.

Example 4 By the same operation as in Example 1, a thin solid electrolyte having a thickness of 18 μm and having mechanical strength was obtained from a PPTA film (thickness: 45 μm) wet with water. As a result of elemental analysis, it was found that the electrolyte content was 50 wt% and the total content of the PPTA polymer and lithium trifluoromethanesulfonate was 99 wt% or more. The obtained solid electrolyte was sandwiched between stainless sheets, and impedance measurement was performed. As a result, room temperature ionic conductivity was 3 × 10 ⁻⁶ S /
There was cm.

Example 5 A PPTA film (film thickness: 197 μm) moistened with water was used.
After being immersed in an aqueous solution of lithium M trifluoromethanesulfonate for 3 days, it was dried under vacuum at 100 ° C. for 5 hours to give a film thickness of 1
A solid electrolyte of 00 μm was obtained. 30 in thermogravimetric analysis
Weight loss due to temperature rise to 0 ° C is 1 wt% or less,
The total content of PPTA polymer and lithium trifluoromethanesulfonate was 99 wt% or more. The obtained solid electrolyte was sandwiched between stainless sheets and impedance measurement was performed at 100 ° C. As a result, the ionic conductivity was 1.3 × 10 ⁻⁵ S / cm.

Example 6 A PPTA film (film thickness: 197 μm) wet with water
After being immersed in an aqueous solution of M bis (trifluoromethanesulfonyl) imide lithium for 3 days, it was dried under vacuum at 100 ° C. for 5 hours to obtain a solid electrolyte having a film thickness of 100 μm. As a result of elemental analysis of this solid electrolyte, it was found that it contained 50 wt% of bis (trifluoromethanesulfonyl) imide lithium, and the total content of PPTA polymer and bis (trifluoromethanesulfonyl) imide lithium was 99 wt% or more. It was The obtained solid electrolyte was sandwiched by stainless steel sheets, and impedance measurement was performed at 100 ° C. As a result, the ionic conductivity was 7 × 10 ⁻⁶ S / c
m.

Example 7 In the same manner as in Example 3, a dry PPTA film (film thickness: 197 μm) of 4M lithium hexafluorophosphate was prepared.
Immerse in an ethylene carbonate solvent solution at a temperature of 80 ° C. for 3 days and dry under vacuum at room temperature for 6 hours to give a film thickness of 100.
A μm film was obtained. As a result of elemental analysis of this solid electrolyte, it was found that the solid electrolyte contained 60 wt% of lithium hexafluorophosphate, and the total content of the PPTA polymer and lithium hexafluorophosphate was about 95 wt%. Further, as a result of thermogravimetric analysis, it was found that 5 wt% of ethylene carbonate was contained. The obtained solid electrolyte was sandwiched between stainless sheets and impedance measurement was performed. As a result, room temperature ionic conductivity was 7 × 10 ⁻⁵ S /
There was cm.

Example 8 After mixing a predetermined amount of lithium hydroxide and cobalt oxide,
LiCoO having an average grain size of 10 μm after heating at 50 ° C. for 5 hours
_Two powders were synthesized. A solution of polyvinylidene fluoride in N-methylpyrrolidone (5 wt.
%) To prepare a slurry. The composition of the solid content in the slurry was LiCoO ₂ (85%), carbon black (8%), polyvinylidene fluoride (7%).
And This slurry was applied onto an aluminum foil by a doctor blade method and dried to prepare a positive electrode sheet having a film thickness of 100 μm.

A needle coke powder having an average particle size of 10 μm was mixed and dispersed in a N-methylpyrrolidone solution of polyvinylidene fluoride (5 wt%) to prepare a slurry. The weight composition of the solid content in the slurry is calculated by measuring the needle coke (9
2%) and polyvinylidene fluoride (8%). This slurry was applied on a stainless foil by a doctor blade method and dried to prepare a negative electrode sheet having a film thickness of 120 μm.

Using the solid electrolyte prepared in Example 1,
The electrode laminate was composed of the positive electrode (LiCoO ₂ ) / solid electrolyte / negative electrode (needle coke). Stainless steel terminals were attached to the positive electrode and the negative electrode of the laminated body of the electrode laminated body, which were respectively connected to the terminals of the glass cell and sealed in an argon atmosphere. Charge and discharge the battery (Hokuto Denko, HJ-101S
Charging was carried out using M6). The inter-electrode potential after charging was 4.2 V, and charging was confirmed.

Example 9 The solid electrolyte prepared in Example 3 was sandwiched between the positive electrode and negative electrode sheets used in Example 8 and charged in the same manner as in Example 8 using a charging / discharging machine. The potential between the electrodes was 4.2 V, and charging could be confirmed.

[0058]

INDUSTRIAL APPLICABILITY The solid electrolyte of the present invention is excellent in heat resistance and mechanical strength and is suitable for use as a battery, an electrochromic device and an electrochemical sensor. Furthermore, a battery using the solid electrolyte of the present invention is safe. It has excellent properties and is industrially useful.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigemitsu Muraoka 6-4100 Asahi-cho, Nobeoka-shi, Miyazaki Asahi Kasei Kogyo Co., Ltd.

Claims (2)

[Claims] 1. A solid electrolyte mainly composed of an aromatic polyamide and an electrolyte, wherein the total content of the aromatic polyamide and the electrolyte in the solid electrolyte is more than 85% by weight, and the amount of the electrolyte in the solid electrolyte is Content is 10-90
Solid electrolyte characterized by being in the range of wt%. 2. A battery in which a positive electrode and a negative electrode are joined via the solid electrolyte according to claim 1.