JP3146655B2 - Battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery which operates reversibly at ambient temperature, and more particularly to an improvement in an electrolyte, a positive electrode and a negative electrode.

[0002]

2. Description of the Related Art Recent microelectronics are
As typified by the power supply for memory backup of various electronic devices, as batteries are stored in electronic devices and integrated with electronic elements and circuits, batteries have become smaller, lighter, thinner and have higher energy density. There is a strong demand for such batteries. In recent years, in the field of primary batteries, small and lightweight batteries such as lithium batteries have already been put into practical use, but their application fields are limited. Therefore, as a battery that replaces the conventional lead battery and nickel-cadmium battery, a secondary battery using a non-aqueous electrolyte that can be reduced in size and weight has attracted more attention. Currently, many research institutions are examining the lack of a material that satisfies practical properties such as characteristics. Therefore, as electrode active materials, those utilizing intercalation or doping phenomena of layered compounds have been particularly studied, and these are expected to have extremely excellent charge / discharge cycle performance.

The use of a carbonaceous material as an electrode active material has also emerged as a solution to problems such as cycle characteristics of the electrode active material. The characteristics of this carbonaceous material are
High doping capacity, low self-discharge rate, excellent cycling characteristics, and most notably, have a base potential very close to lithium metal.

[0004] On the other hand, conventionally, as a battery using an electrochemical reaction or an electrochemical device other than a battery, that is, an electrolyte such as an electric double layer capacitor or an electrochromic element, a liquid electrolyte, particularly an organic electrolyte, is ionic. Although a solution in which a compound is dissolved has been used, the above-mentioned liquid electrolyte is liable to cause leakage of liquid to the outside of the component, elution of an electrode substance, and further volatilization of the liquid electrolyte itself. And the like, and scattering of the electrolytic solution in the sealing step have been problems.

[0005] Therefore, in order to improve the liquid leakage resistance and the long-term storage property, an ion-conductive polymer compound having high ion conductivity has been reported, and further research has been conducted as one of means for solving the above problems. Is underway.

The ion conductive polymer compounds currently being studied are homopolymer or copolymer linear polymers, network crosslinked polymers or comb polymers having ethylene oxide as a basic unit. For the purpose of increasing the ionic conductivity of the polymer, it has been proposed to use a cross-linked polymer or comb polymer to prevent crystallization of the ion-conductive polymer compound. In particular, an ion conductive polymer compound using the above network crosslinked polymer is useful because it has high mechanical strength and good ionic conductivity at low temperatures.

Further, when the above-mentioned ion-conductive polymer compound is applied as an electrolyte for an electrochemical device, it is necessary to make the electrolyte thinner in order to lower the internal resistance. In particular, for the present inventors, when designing a battery called a thin battery (thickness per unit cell of 100 to 500 μm (or sheet-shaped battery)), which is a battery that is smaller and lighter and has a high energy density, It can be said that thinning is the ultimate proposition. In the case of the above-mentioned ion-conductive polymer compound, a uniform thin film can be easily processed into an arbitrary shape, but this method poses a problem. For example,
A method of casting a solution of the ion-conductive polymer compound to evaporate and remove the solvent, or a method of applying a polymerizable monomer or macromer on a substrate and performing heat polymerization,
Alternatively, there is a method of curing by irradiation with actinic rays.

Further, the present inventors dispose an electrolyte layer comprising the above-mentioned ion-conductive polymer compound between a composite cathode and a composite anode comprising the above-mentioned ion-conductive polymer compound and an electrochemically active substance. Thereby, the above-mentioned thin battery (sheet-shaped battery) was manufactured.

However, when the above ion conductive polymer compound is applied to a battery, the following has occurred. That is, when the charge and discharge cycle is repeated, water is extracted from the composite electrode with the repetition, passes through the separator layer made of the ion-conductive polymer compound, reaches the lithium metal as the negative electrode, and Lithium metal and moisture react with each other to generate hydrogen gas, causing problems such as swelling of the sheet-shaped battery. As a result, an increase in the internal pressure of the battery causes an accident such as expansion and rupture of the battery. Problems in reliability and safety.

On the other hand, in producing the above-mentioned sheet-like battery, as a method of forming the above-mentioned composite positive electrode, composite negative electrode and electrolyte layer, a method of mainly heat-polymerizing has been conventionally used simply and often. However, the heating polymerization time is extremely long and it is difficult to improve the production rate, the temperature gradient is easily generated in the heating furnace, and it is necessary to heat in an inert gas atmosphere. There was a problem of becoming large.

[0011]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, an object of the present invention is to improve battery characteristics and manufacture a high-performance electrode. It provides a battery with very high workability, no long-term liquid leakage, and high long-term reliability and safety. In addition, small size and light weight with high performance and high energy density A sheet-shaped battery is provided.

[0012]

According to the present invention, there is provided an ion-conductive polymer compound composed of a polymer in which at least one ionic compound is dissolved. A composite positive electrode (A) and a composite negative electrode (B ₁ ) and / or a negative electrode (A) comprising a polymer compound having a structure and having ion conductivity, an electrochemically active substance, and optionally an electron conductive substance; B ₂ ), comprising: an electrolyte (C) comprising an ion-conductive polymer compound composed of a polymer in which at least one ionic compound is dissolved, wherein the composite cathode (A) and A first aspect of the present invention is that the composite negative electrode (B) contains a Group VIII element of the periodic table in addition to the electrochemically active substance, and the Group VIII element of the periodic table is Pd.

The above-mentioned ion-conductive polymer compound is a polymer compound which is a polyether having a reactive double bond in which at least one ionic compound is dissolved, and the polymer compound which forms a crosslinked network structure by a polymerization reaction According to a second aspect of the present invention, there is provided a polymer compound characterized by the following: a method of forming the composite positive electrode (A), the composite negative electrode (B ₁ ), and the electrolyte layer (C) includes ultraviolet light, ionization A third aspect of the present invention is to form the composite electrode and the electrolyte layer by irradiation with actinic rays such as sexual radiation.

In a fourth aspect of the present invention, the composite anode comprises a carbonaceous material and the ion-conductive polymer compound, and the ion-conductive polymer compound dissolves the ionic compound. The composite positive electrode (A), the composite negative electrode (B ₁ ), and the composite negative electrode (B) comprising the electrochemically active substance and the ion-conductive polymer compound. The above object has been achieved by providing an electrolyte layer (C) composed of an ion-conductive polymer compound.

It has been confirmed that a reactive double bond remains in the above-mentioned composite positive electrode and composite negative electrode even when cured by irradiation with actinic rays such as ultraviolet rays or ionizing radiation. In particular, it has been confirmed that the above-mentioned reactive double bond remains at a maximum of about 5% even when irradiated with ionizing radiation. Therefore, the composite positive electrode and the composite negative electrode are added to the periodic table VI.
By adding a Group II element, for example, when Pd is added, hydrogen gas generated by lithium, moisture, and the like is absorbed by a reactive double bond portion by a catalytic action of Pd to form an inactive single bond. Swelling can be suppressed, and unreacted monomers can be eliminated.

The ion-conductive polymer compound obtained by dissolving a metal salt in a polymer compound obtained by cross-linking a polyether is a cross-linked polymer formed by an ether bond. It has a low structure, and the migration of dissolved metal salt ions becomes extremely easy.

For example, a polymer having a crosslinked network structure obtained by reacting a mixture of polyethylene glycol dimethacrylate or diacrylate with polyethylene glycol monomethacrylate or monoacrylate may be used.

Next, as the ionic compound dissolved in the polymer compound thus obtained, for example, LiCl
O ₄ , LiBF ₄ , LiAsF ₆ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , Li
_{SCN, LiBr, LiI, Li 2} B 10 Cl 10, NaClO 4, NaI, NaSCN
Li, Na, or K 1 such as, NaBr, KClO ₄ , KSCN, etc.
Inorganic ion salts containing species, (CH ₃ ) ₄ NBF ₄ , (CH ₃ ) ₄ NBr, (C ₂ H
₅ ) ₄ NClO ₄ , (C ₂ H ₅ ) ₄ NI, (C ₃ H ₇ ) ₄ NBr, (nC ₄ H ₉ ) ₄ NClO ₄ ,
(nC ₄ H ₉ ) ₄ NI, (C ₂ H ₅ ) ₄ N-maleate, (C ₂ H ₅ ) ₄ N-benzoate
And quaternary ammonium salts such as (C ₂ H ₅ ) ₄ N-phtalate, and organic ion salts such as lithium stearylsulfonate, lithium octylsulfonate and lithium dodecylbenzenesulfonate. These ionic compounds may be used in combination of two or more.

The mixing ratio of such an ionic compound is as follows:
The ratio of the ionic compound is 0.0001 to 5.0 mol, preferably 0.005 to 2.0 mol, based on the ether bond oxygen of the polymer compound. If the amount of the ionic compound is too large, an excessive amount of the ionic compound, for example, an inorganic ionic salt is not dissociated, but merely mixed, resulting in a reduction in ionic conductivity.

The mixing ratio of the ionic compound is as follows:
The appropriate compounding ratio differs depending on the electrode active material. For example,
In a battery using intercalation of a layered compound, the vicinity where the ionic conductivity of the electrolyte is maximized is preferable, and in a battery using a conductive polymer utilizing a doping phenomenon as an electrode active material, the charge is sufficient. It is necessary that the ion concentration in the electrolyte can respond to the change due to the discharge.

The method of containing the ionic compound is not particularly limited. For example, a method of dissolving the compound in an organic solvent such as methyl ethyl ketone or tetrahydrofuran, uniformly mixing the compound with the organic compound, and removing the organic solvent by vacuum reduction. And the like.

Next, in the present invention, the ion-conductive polymer compound may contain a substance capable of dissolving the ionic compound contained in the ion-conductive polymer compound, and this kind of substance may be contained. Thereby, the ionic conductivity can be significantly improved without changing the basic skeleton of the polymer compound.

Examples of the substance capable of dissolving the ionic compound include cyclic carbonates such as propylene carbonate and ethylene carbonate; cyclic esters such as γ-butyrolactone; tetrahydrofuran or derivatives thereof;
Ethers such as 1,3-dioxane, 1,2-dimethoxyethane and methyldiglyme; nitriles such as acetonitrile and benzonitrile; dioxalane or a derivative thereof; sulfolane or a derivative thereof alone or a mixture of two or more thereof; Is mentioned. However, it is not limited to these. The mixing ratio and the mixing method are arbitrary.

The above ion conductive polymer compound,
The electrolyte layer (separator) may be a sheet of the ion-conductive polymer compound alone and disposed between the composite positive electrode and the composite negative electrode, or may be provided on the composite positive electrode surface or the composite negative electrode surface. It is also possible to form a sheet-shaped battery by applying and curing the liquid composition of the hydrophilic polymer compound.

The method of applying the ion-conductive polymer compound may be, for example, a roller coating such as an applicator roll, a screen coating, a doctor blade method, a spin coating, or a bar coating method. It is desirable to apply in the shape of, but is not limited thereto.

Further, by using the above-mentioned ion-conductive polymer compound as an electrolyte layer (separator), it is possible to suppress the generation of lithium dendrites in the periphery of the composite negative electrode, and it is excellent in mechanical strength and heat resistance. It is possible to provide a stable and electrochemically stable electrolyte layer.

The positive electrode active material used in the composite positive electrode of the present invention includes the following battery electrode materials.

That is, CuO, Cu ₂ O, Ag ₂ O, CuS, CuSO
Group IV metal compounds such as ₄ , IV such as TiS ₂ , SiO ₂ , SnO
Group metal _{compounds, V 2 O 5, V 6} O 12, VOx, Nb 2 O 5, Bi 2 O 3,
Group V metal compounds such as _{Sb 2 O 3, CrO 3,} Cr 2 O 3, MoO 3, Mo
S _2, WO _3, VI metal compounds such as _{SeO 2, MnO 2, Mn 2} O 3
Group VII metal compounds such _{as, Fe 2 O 3, FeO,} Fe 3 O 4, Ni
Group VIII metal compounds such as ₂ O ₃ , NiO, CoO ₃ , CoO,
Or, represented by a general formula Li _x MX ₂ , Li _x MN _y X ₂ (M and N are metals of groups I to VIII, and X is a chalcogen compound such as oxygen and sulfur). Metal compounds such as cobalt-based composite oxides or lithium-manganese-based composite oxides; conductive polymer compounds such as polypyrrole, polyaniline, polyparaphenylene, polyacetylene, and polyacene-based materials; and pseudographite-structured carbonaceous materials. However, the present invention is not limited to these.

Further, examples of the negative electrode active material used in the composite negative electrode include the following battery electrode materials.

That is, a carbonaceous material such as carbon; [for example, the above carbonaceous material is analyzed by X-ray diffraction or the like; lattice spacing (d002) 3.35 to 3.40Å; crystallite size in the a-axis direction La 200 200 More than crystallite size in c-axis direction Lc 200 mm or more True density 2.00 to 2.25 g / cm
^{3 Further} , carbon powder (an average particle diameter of 15 μm or less) or carbon fiber obtained by calcining anisotropic pitch at a temperature of 2000 ° C. or higher is desirable, but is not limited to these ranges. Or lithium metal, lithium-aluminum, lithium-lead, lithium-tin, lithium-aluminum-
Lithium metal-containing alloys, such as, but not limited to, tin, lithium-gallium, and wood alloys. These negative electrode active materials can be used alone or
Combinations of more than one species are possible.

The method of applying the composite positive electrode and the composite negative electrode of the present invention includes, for example, roller coating using an applicator roll, screen coating, and the like.
It is desirable to apply to an arbitrary thickness and an arbitrary shape by using a means such as a doctor blade method, spin coating, and bar coder, but it is not limited thereto. When these means are used, it is possible to increase the actual surface area of the electrochemically active substance that comes into contact with the electrolyte layer and the current collector.

In these cases, if necessary, carbon such as graphite, carbon black, acetylene black or the like (the carbon herein has completely different characteristics from the carbon in the above-mentioned negative electrode active material). ) And a conductive material such as a metal powder and a conductive metal oxide can be mixed in the composite positive electrode and the composite negative electrode to improve electron conduction.

When producing the above-mentioned composite positive electrode and composite negative electrode, several kinds of dispersants and dispersion media can be added to obtain a uniform mixed dispersion system. Further, it is also possible to add a thickener, a bulking agent, a tackifier and the like.

The ionizing radiation described in the claims is γ
Ray, X-ray, electron beam, neutron beam and the like. The method using these ionizing radiations when cross-linking the ion-conductive polymer compound is very efficient. That is,
Not only the energy efficiency of the ionizing radiation, but also, for example, when forming various composite positive electrodes, composite negative electrodes and electrolytes, the degree of crosslinking of the ion-conductive polymer compound can be easily controlled. By controlling the irradiation dose of radiation, it becomes possible to produce electrochemically optimal electrodes and electrolytes.

Materials such as aluminum, stainless steel, titanium, and copper are preferable for the positive electrode current collector, and materials such as stainless steel, iron, nickel, and copper are preferable for the negative electrode current collector. is not.

[0036]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. (Example 1) The sheet-shaped battery of Example 1 was manufactured according to the following procedure. a) Manganese dioxide is used as the positive electrode active material of the battery, acetylene black is used as the conductive agent, and polyethylene glycol diacrylate (molecular weight: 5000) and polyethylene glycol monoacrylate (molecular weight: 400) are in a weight ratio of 6: 4. A mixture of an organic compound and a mixed positive electrode was used as a composite positive electrode.

The method for producing the composite positive electrode is as follows. That is, a mixture of vanadium pentoxide and acetylene black in a weight ratio of 85:15, 10 parts by weight of the above organic compound, 1 part by weight of lithium perchlorate, 20 parts by weight of propylene carbonate, and Palladium on 4-to
A mixture of 0.2 parts by weight of 8-mesh carbon (Palladium content 1.0%) (manufactured by Aldrich) was mixed in a dry inert gas atmosphere at a weight ratio of 10: 3. These mixtures were cast on a current collector having a conductive carbon film formed on the surface of a positive electrode current collector plate made of stainless steel. Then, in a dry inert gas atmosphere, electron dose 10M
The composite positive electrode was cured by irradiating rad electron beams. The thickness of the composite positive electrode film formed on the positive electrode current collector was 60 μm.

B) Lithium metal was used as a negative electrode active material of a battery, and this was pressed on a negative electrode current collector plate made of stainless steel.

Next, polyethylene glycol diacrylate (molecular weight: 5,000) and polyethylene glycol monoacrylate (molecular weight: 400) were used to form the ion-conductive polymer compound layer of the present invention on the lithium metal.
A mixture of 30 parts by weight of the organic compound, 6 parts by weight of lithium perchlorate, and 64 parts by weight of propylene carbonate, which were mixed in Example 4, was cast on the lithium metal, and an electron beam having an electron dose of 8 Mrad was applied in an inert gas atmosphere. Irradiated and cured. The thickness of the electrolyte layer thus obtained is 2
It was 0 μm.

C) By contacting the electrolyte / lithium / negative electrode current collector obtained in b) with the positive electrode current collector / composite positive electrode obtained in a), sheet batteries were produced, respectively.

FIG. 1 is a sectional view of a sheet-shaped battery of the present invention. In the figure, reference numeral 1 denotes a positive electrode current collector made of stainless steel.
Also serves as an exterior. Reference numeral 2 denotes a composite positive electrode, in which manganese dioxide was used as a positive electrode active material, acetylene black was used as a conductive agent, and the ion-conductive polymer compound of the present invention was used as a binder. Reference numeral 3 denotes an electrolyte layer made of the ion-conductive polymer compound of the present invention. 4 is metallic lithium,
Reference numeral 5 denotes a negative electrode current collector made of stainless steel, which also serves as an exterior. Reference numeral 6 denotes a sealing agent made of modified polypropylene.

(Comparative Example 2) The same manufacturing method and cell structure as in the sheet-shaped battery of Example 2 except that the composite positive electrode contained no Palladium on 4-to 8-mesh carbon in the composite positive electrode of Example 2. Thus, a sheet-like battery of Comparative Example 2 was produced.

The electrode area of the sheet batteries of Example 1 and Comparative Example 1 can be variously changed depending on the manufacturing process. In Example 1 and Comparative Example 1, the electrode area is 100 cm ^2. Was prepared.

(Experiment 1) The initial discharge characteristics of the sheet batteries of Example 1 and Comparative Example 1 when discharged at 25 ° C. at 0.1 mA / cm ² and the discharge characteristics after storage at 60 ° C. for 100 days were examined. FIG.
Are the discharge characteristics immediately after cell fabrication (initial discharge characteristics) and 60
It shows the discharge characteristics after storage at 100 ° C for 100 days. As is clear from FIG. 2, the sheet-shaped battery of Example 1 of the present invention is superior to the sheet-shaped battery of Comparative Example 1 in initial discharge characteristics and discharge characteristics after storage at 60 ° C. for 100 days. Is recognized. As a cause of this, in the sheet-shaped battery of the present embodiment, since there is no swelling due to gas generation described later,
It is conceivable that the contact between the composite positive electrode / electrolyte layer and the negative electrode / electrolyte layer is good.

(Experiment 2) Using the sheet batteries of Example 1 and Comparative Example 1, the number of sheet batteries swelled after storage at 60 ° C. for 100 days was examined. As a result, as shown in Table 1,
In the sheet-shaped battery of Comparative Example 1, swelling was observed in 28% of the cells. However, in the sheet-shaped battery of Example 1 of the present invention to which Palladium on 4-to 8-mesh carbon was added, No swelling was observed.

[0046]

Example 2 A sheet-like battery of Example 2 was manufactured according to the following procedure. a) Vanadium pentoxide as a positive electrode active material of a battery, acetylene black as a conductive agent, and a weight ratio of polyethylene glycol diacrylate (molecular weight: 5000) and polyethylene glycol monoacrylate (molecular weight: 400) of 6: 4. The mixture of the organic compounds mixed in the ratio was used as a composite positive electrode.

The method for producing this composite positive electrode is as follows. That is, a mixture of vanadium pentoxide and acetylene black in a weight ratio of 85:15, 10 parts by weight of the organic compound, 1 part by weight of lithium hexafluoroarsenate, 10 parts by weight of ethylene carbonate, and 10 parts by weight of 2-methyltetrahydrofuran Parts by weight and Palladium on 4-to 8-meshca
rbon (Palladium content 1.0%) (Aldrich)
A mixture of 0.2 parts by weight was mixed in a dry inert gas atmosphere at a weight ratio of 10: 3. These mixtures were cast on a current collector having a conductive carbon film formed on the surface of a positive electrode current collector plate made of stainless steel. Thereafter, the composite positive electrode was cured by irradiating an electron beam with an electron dose of 10 Mrad in a dry inert gas atmosphere. The thickness of the composite positive electrode film formed on the positive electrode current collector was 6
It was 0 μm.

B) Lithium metal was used as the negative electrode active material of the battery, and this was pressed on a negative electrode current collector plate made of stainless steel.

Next, in order to form the ion-conductive polymer compound layer of the present invention on the lithium metal, 30 parts by weight of the organic compound, 6 parts by weight of lithium hexafluoroarsenate, 32 parts by weight of ethylene carbonate, and A mixture of 32 parts by weight of 2-methyltetrahydrofuran was cast on the lithium metal, and cured by irradiating an electron beam with an electron dose of 8 Mrad in an inert gas atmosphere. The thickness of the electrolyte layer thus obtained was 20 μm.

C) By contacting the electrolyte / lithium / negative electrode current collector obtained in b) with the positive electrode current collector / composite positive electrode obtained in a), sheet batteries were produced, respectively.

(Comparative Example 2) The same manufacturing method and cell structure as in the sheet-like battery of Example 2 except that the composite positive electrode contained no Palladium on 4-to 8-mesh carbon in the composite positive electrode of Example 2. Thus, a sheet-like battery of Comparative Example 2 was produced.

The electrode areas of the sheet batteries of Example 2 and Comparative Example 2 can be variously changed depending on the manufacturing process. In Example 2 and Comparative Example 2, the electrode area is 100 cm ^2. Was prepared.

(Experiment 3) Using the sheet batteries of Example 2 and Comparative Example 2, a charge / discharge cycle test was performed immediately after cell production and after storage at 60 ° C. for 100 days. 50 μA / cm ² at 25 ° C
A constant current charge / discharge cycle test was performed. The charge / discharge cycle test conditions were a charge end voltage of 3.2 V and a discharge end voltage of 2.0 V. FIG. 3 shows the relationship between the number of charge / discharge cycles and the battery capacity. As can be seen from FIG.
It can be seen that the sheet-shaped battery according to the present invention exhibits excellent charge / discharge cycle characteristics as compared with the sheet-shaped battery of the comparative example. The cause may be that the sheet-shaped battery of this example has good contact between the composite positive electrode / electrolyte layer and the negative electrode / electrolyte layer because no swelling due to gas generation is present.

(Experiment 4) Using the sheet batteries of Example 2 and Comparative Example 2, the number of sheet batteries swelled after storage at 60 ° C. for 100 days was examined. As a result, as shown in Table 2,
In the sheet-shaped battery of Comparative Example 2, swelling was observed in 20% of the cells. However, in the sheet-shaped battery of Example 2 of the present invention, Palladium on 4-to 8-mesh carbon was added. No swelling was observed.

[0056]

Example 3 A sheet-like battery of Example 3 of the present invention was manufactured according to the following procedure. a) LiCoO ₂ was used as a positive electrode active material of a battery, acetylene black was used as a conductive agent, and polyethylene glycol diacrylate (molecular weight: 5000) and polyethylene glycol monoacrylate (molecular weight: 400) were used.
A mixture mixed with an organic compound mixed at a weight ratio of 4 was used as a composite positive electrode.

The method for producing the composite positive electrode is as follows. That is, LiCoO ₂ and acetylene black
In a mixture of 5:15 by weight, 10 parts by weight of the organic compound, 1 part by weight of lithium tetrafluoroborate, 1,
10 parts by weight of 2-dimethoxyethane and 10 parts by weight of γ-butyrolactone and Palladium on 4-to 8-mesh carbo
n (Palladium content 1.0%) (Aldrich) 0.
A mixture of 2 parts by weight is dried in an inert gas atmosphere,
They were mixed at a weight ratio of 10: 3. These mixtures were cast on a current collector having a conductive carbon film formed on the surface of a positive electrode current collector plate made of aluminum. Thereafter, the composite positive electrode was cured by irradiating it with an electron beam having an electron dose of 12 Mrad in a dry inert gas atmosphere. The thickness of the composite positive electrode film formed on the positive electrode current collector was 60 μm.

Next, 30 parts by weight of the organic compound, 6 parts by weight of lithium tetrafluoroborate, 32 parts by weight of 1,2-dimethoxyethane and γ A mixture of 32 parts by weight of butyrolactone was cast on the composite positive electrode in a dry inert gas atmosphere, and then irradiated with an electron beam of 8 Mrad in a dry inert gas atmosphere to increase the ion conductivity. The molecular compound layer was cured. The thickness of the electrolyte layer thus obtained was 25 μm.

B) Carbon powder was used as the negative electrode active material of the battery, and mixed with an organic compound in which polyethylene glycol diacrylate (molecular weight: 5,000) and polyethylene glycol monoacrylate (molecular weight: 400) were mixed at a weight ratio of 6: 4. This was used as a composite negative electrode.

The method for producing this composite negative electrode is as follows. That is, 1 part by weight of lithium tetrafluoroborate, 10 parts by weight of 1,2-dimethoxyethane and 10 parts by weight of γ-butyrolactone
Parts by weight and Palladium on 4-to 8-mesh carbon (Palladium
A mixture of 0.2 parts by weight (dium content 1.0%) (manufactured by Aldrich) was mixed in a dry inert gas atmosphere at a weight ratio of 8: 2. These mixtures were cast on a negative electrode current collector made of stainless steel. Thereafter, the composite negative electrode was cured by irradiating it with an electron beam having an electron dose of 15 Mrad in a dry inert gas atmosphere. The thickness of the composite negative electrode formed on the negative electrode current collector was 30 μm.

Next, 30 parts by weight of the organic compound, 6 parts by weight of lithium tetrafluoroborate, 32 parts by weight of 1,2-dimethoxyethane, and γ A mixture of 32 parts by weight of butyrolactone was cast on the composite anode in a dry inert gas atmosphere, and then irradiated with an electron beam of 8 Mrad in a dry inert gas atmosphere to increase the ion conductivity. The molecular compound layer was cured. The thickness of the electrolyte layer thus obtained was 25 μm.

C) The electrolyte layer obtained in b) / composite negative electrode /
Negative electrode current collector, positive electrode current collector obtained in a) / composite positive electrode /
By bringing the electrolyte layers into contact, a sheet-like battery of Example 2 of the present invention was produced.

Comparative Example 3 In the composite positive electrode and the composite negative electrode of Example 3, the Pallad was added in the composite positive electrode and the composite negative electrode.
A sheet-shaped battery of Comparative Example 2 was manufactured using the same manufacturing method and cell structure as the sheet-shaped battery of Example 3 except that ium on 4-to 8-mesh carbon was not included.

The electrode area of the sheet batteries of Example 3 and Comparative Example 3 can be variously changed depending on the manufacturing process. In Example 3 and Comparative Example 3, the electrode area is 100 cm ^2. Was prepared.

(Experiment 5) Using the sheet batteries of Example 3 and Comparative Example 3, a charge / discharge cycle test at 25 ° C. and a constant current of 50 μA / cm ^{2 and} a charge / discharge cycle test at 60 ° C. 100 days later were performed. . The charge end voltage is 4.1 V, the discharge end voltage is 2.7
The charge / discharge cycle test was performed as V. FIG. 4 shows the relationship between the number of charge / discharge cycles and the battery capacity.
As can be seen from FIG. 4, the sheet battery according to the present invention is:
It can be seen that the battery exhibits excellent charge / discharge cycle characteristics as compared with the sheet battery of the comparative example. The cause may be that the sheet-shaped battery of this example has good contact between the composite positive electrode / electrolyte layer and the composite negative electrode / electrolyte layer because there is no swelling due to gas generation.

(Experiment 6) Using the sheet batteries of Example 3 and Comparative Example 3, the number of sheet batteries swelled after storage at 60 ° C. for 100 days was examined. As a result, as shown in Table 3,
In the sheet battery of Comparative Example 3, swelling was observed in 42.5% of the cells. However, in the sheet battery of Example 3 of the present invention to which Palladium on 4-to 8-mesh carbon was added, No swelling was observed.

[0068]

[0069]

As is apparent from the above description, in the battery using the ion-conductive polymer compound of the present invention, the battery containing Pd in the composite positive electrode (A) and the composite negative electrode (B) is the same as the conventional battery. In comparison with the battery of the above, the battery characteristics (in particular, cycle characteristics and cycle characteristics after long-term storage) can be improved and a high-performance electrode can be manufactured. By forming the electrolyte layer, it has become possible to provide a battery which has extremely high workability, has no fear of liquid leakage to the outside, and has high long-term reliability and safety. From these facts, there is an effect that the performance of a battery, particularly a small and light sheet battery having high performance and high energy density can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a sheet-shaped battery of the present invention.

FIG. 2 shows the initial discharge characteristics and the discharge characteristics after storage at 60 ° C. for 100 days of the sheet batteries of Example 1 and Comparative Example 1.

FIG. 3 is a graph showing the relationship between the number of charge / discharge cycles and the battery capacity of the sheet batteries of Example 2 and Comparative Example 2.

FIG. 4 is a graph showing the relationship between the number of charge / discharge cycles and the battery capacity of the sheet batteries of Example 3 and Comparative Example 3. Reference Signs List 1 positive electrode current collector 2 composite positive electrode 3 electrolyte layer 4 metallic lithium 5 negative electrode current collector 6 sealing agent

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01M 10/36-10/40 H01M 4/02-4/04 H01M 4/62

Claims (5)

(57) [Claims] 1. An ion-conductive polymer compound composed of a polymer substance in which at least one ionic compound is dissolved, having a polyether structure and having ion conductivity. Composite anode (A) and composite anode (B1) composed of molecular compound and electrochemically active substance
And / or a negative electrode (B2): a battery comprising an electrolyte (C) made of an ion-conductive polymer compound composed of a polymer substance in which at least one ionic compound is dissolved, A) and the composite anode (B1
), Wherein the battery contains a Pd element in addition to the electrochemically active substance. 2. The polymer compound, wherein the ion-conductive polymer compound is a polyether having a reactive double bond in which at least one ionic compound is dissolved, and forms a crosslinked network structure by a polymerization reaction. The battery according to claim 1, wherein the battery is a polymer compound. 3. The composite positive electrode (A) and the composite negative electrode (B1)
3. The battery according to claim 1, wherein the composite electrode and the electrolyte layer are formed by irradiating active rays such as ultraviolet rays and ionizing radiation as a method of forming the electrolyte layer (C). Wherein the composite negative electrode (B1) is, the battery according to claim 1, wherein characterized in that it is composed of a carbonaceous material and the ion-conductive polymer compound. Wherein said ion-conductive polymeric compound is, cell according to claim 1, 2, 3 or 4, wherein the containing a substance capable of dissolving the ionic compound.