JP7649550B2 - battery - Google Patents

Description

The present invention relates to a capacitor battery and a secondary battery, and a method for manufacturing the battery. The capacitor battery and secondary battery of the present invention mainly use a perchlorate aqueous solution, a saturated perchlorate aqueous solution, etc. as the electrolyte.

The most widely used lithium-ion secondary battery is the manganese lithium secondary battery (ML type), which uses a manganese composite oxide for the positive electrode and a lithium-aluminum alloy for the negative electrode.
Patent Document 1 discloses a lithium ion secondary battery having features such as a positive electrode material for the lithium ion secondary battery.

Patent Publication No. 2020-155223

Conventional lithium-ion and sodium-ion secondary batteries use organic electrolytes, which pose a risk of fire.

The electromotive force of a secondary battery is governed by the redox reaction at the negative and positive electrodes. For example, in lithium-ion batteries, the electromotive force varies from 3V or more to 3V or less. This is because the reactions that occur at the negative and positive electrodes are different.

The present invention uses a saturated lithium perchlorate aqueous solution as the electrolyte for the capacitor battery. Aqueous perchlorate solutions have a wide potential window and therefore exhibit excellent properties as an electrolyte for secondary batteries.

The capacitor battery and secondary battery of the present invention use, as the electrolyte, an aqueous solution of any one of lithium perchlorate ( _LiClO4 ), sodium perchlorate ( _NaClO4 ), barium perchlorate (Ba( _ClO4 ) ₂ ), magnesium perchlorate (Mg(ClO4) ₂ ), or a mixture of these aqueous solutions. Each aqueous solution of perchloric acid is preferably a saturated aqueous solution of perchloric acid of 98% or more.
At least the positive electrode is made of or formed from an iron complex. At least one of the positive and negative electrodes is _coated with _Fe2O3 .
Since the battery of the present invention has a capacitor structure, it is sometimes called an electric double layer capacitor battery.

In one embodiment of the present invention, a capacitor battery, secondary battery, etc., is constructed with a negative electrode made of graphite, or a mixture of activated carbon, or a mixture of graphite and activated carbon, and a positive electrode made of graphite, or a mixture of _LiCoO2 (or a material that does not change structure when oxidized), or a mixture of graphite and _LiCoO2 .

A separator 204 is disposed between the positive electrode material 221 and the negative electrode material 231. The separator 204 is impregnated with an aqueous solution of lithium perchlorate (LiClO ₄ ). The positive electrode 205 and the negative electrode 206 are insulated by a gasket 207.

In one embodiment of the present invention, a capacitor battery, secondary battery, etc., has a positive electrode 205 and a negative electrode 206 formed on one substrate or film 301. An electrolyte solution 222 is placed on the substrate or film 301, or the positive electrode 205 and the negative electrode 206 are immersed in the electrolyte solution 222.

A positive electrode material 221 and a negative electrode material 231 are disposed adjacent to each other on a substrate 301a and a substrate 301b. A positive electrode material 221 is disposed on the substrate 301b facing the positive electrode material 221 on the substrate 301a. A negative electrode material 231 is disposed on the substrate 301b facing the negative electrode material 231 on the substrate _301a . The surfaces of the positive electrode material 221 and the negative electrode material 231 are coated with _Fe2O3 . The space between the substrates 301a and 301b is sealed with a gasket 207, and is filled with an electrolyte 222 consisting of an aqueous perchlorate solution.

The battery of the present invention comprises a negative electrode made of a mixture of graphite and activated carbon, a positive electrode containing lithium cobalt oxide, and an aqueous solution of lithium perchlorate filled between the positive and negative electrodes.

The battery of the present invention comprises a negative electrode made of a mixture of graphite and activated carbon, a positive electrode containing graphite and lithium cobalt oxide, and an aqueous solution of lithium perchlorate filled between the positive electrode and the negative electrode, and the ratio of the graphite in the positive electrode to the material mixed therewith is 1:0.8 to 1:1.5.

The battery of the present invention comprises a negative electrode made of a mixture of graphite and activated carbon, a positive electrode made of a low-spin iron(II) complex material, and an electrolyte filled between the positive electrode and the negative electrode, the electrolyte being any one of lithium perchlorate ( _LiClO4 ), sodium perchlorate ( _NaClO4 ), barium perchlorate (Ba( _ClO4 ) ₂ ), and magnesium perchlorate (Mg(ClO4) ₂ ).

The low-spin iron(II) complex material is preferably any one of [Fe(phen) ₃ ] ²⁺ , [Fe(bipy) ₃ ] ²⁺ , and [Fe(terpy) ₃ ] ²⁺ .

The battery of the present invention also comprises a negative electrode and a positive electrode made of a mixture of graphite and activated carbon, and an electrolyte filled between the positive electrode and the negative electrode, the electrolyte being any one of lithium perchlorate ( _LiClO4 ), sodium perchlorate ( _NaClO4 ), barium perchlorate (Ba( _ClO4 ) ₂ ), and magnesium perchlorate (Mg(ClO4) ₂ ).
At least one of the negative electrode and the positive electrode is preferably coated with Fe ₂ O ₃ .
The negative electrode and the positive electrode are formed or arranged adjacent to each other on the same substrate, sheet or film, and are formed or arranged so that there is a step between the negative electrode and the positive electrode.

The capacitor battery, secondary battery, etc. of the present invention uses a saturated aqueous perchlorate solution as the electrolyte, so there is no risk of fire. In addition, the conductivity of a saturated aqueous perchlorate solution is about 10 times higher than that of an organic electrolyte, so it can store large amounts of power, can be charged quickly, and can achieve a high current capacity.

By using an aqueous electrolyte (perchlorate aqueous solution) in a capacitor battery, the conductivity of the battery is increased while eliminating the risk of fire. In addition, there is no need to use a dry room to remove moisture in the capacitor battery manufacturing process, which reduces manufacturing equipment costs.

In the capacitor battery, secondary battery, etc. of the present invention, the positive electrode 205 and the negative electrode 206 are formed on a single substrate or film 301, so it is possible to construct a battery that does not use a separator 204. Therefore, there is no need to use a separator 204, and the positive electrode 205 and the negative electrode 206 will not short-circuit.

1A and 1B are diagrams illustrating the configuration and an explanatory diagram of a capacitor battery and a secondary battery of the present invention. 1 is a perspective view and a partial cross-sectional view of a capacitor battery and a secondary battery of the present invention. FIG. 2 is an explanatory diagram of a cyclic voltammogram (CV) of a saturated aqueous perchlorate solution. FIG. 1 is an explanatory diagram of a cyclic voltammogram (CV) and temperature change of a saturated aqueous lithium perchlorate solution. FIG. 2 is an explanatory diagram of a saturated aqueous lithium perchlorate solution and the conductivity of a saturated aqueous lithium perchlorate solution and its change with temperature. 3A to 3C are explanatory diagrams illustrating the charge and discharge operations of the capacitor battery and secondary battery of the present invention. 3A to 3C are explanatory diagrams illustrating the charge and discharge operations of the capacitor battery and secondary battery of the present invention. FIG. 2 is an explanatory diagram illustrating the characteristics of a capacitor battery and a secondary battery according to the present invention. FIG. 2 is an explanatory diagram illustrating the characteristics of a capacitor battery and a secondary battery according to the present invention. FIG. 2 is an explanatory diagram illustrating the characteristics of a capacitor battery and a secondary battery according to the present invention. FIG. 2 is an explanatory diagram illustrating the characteristics of a capacitor battery and a secondary battery according to the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A to 1C are explanatory diagrams illustrating a method for producing a capacitor battery and a secondary battery according to the present invention. 1A to 1C are explanatory diagrams illustrating a method for producing a capacitor battery and a secondary battery according to the present invention. 1A to 1C are explanatory diagrams illustrating a method for producing a capacitor battery and a secondary battery according to the present invention. 1A to 1C are explanatory diagrams illustrating a method for producing a capacitor battery and a secondary battery according to the present invention. 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention; 1A and 1B are configuration diagrams and explanatory diagrams of a capacitor battery and a secondary battery of the present invention;

The following describes an embodiment of the capacitor battery and secondary battery of the present invention with reference to the drawings.

In each drawing for explaining the embodiment of the invention, elements having the same function are given the same reference numerals, and the description thereof may be omitted. In addition, the embodiments of the present invention described in this specification may be combined in part or in whole with each other.
In the drawings for explaining the embodiments of the invention, the drawings may be enlarged, reduced, or omitted in order to facilitate understanding and explanation and to facilitate illustration.

In addition, in the explanation or illustration of the embodiments of the present invention, the positive electrode and the negative electrode may be explained or illustrated as the concepts of a container or an electrode. They may also be explained as the concepts of the electrode material used. They may also be explained as the concepts including the container and the electrode material.

In charging an electric double layer capacitor, the adsorption of cations to the negative electrode is driven by electrostatic interactions between the negative electrode and cations. The storage capacity and charge/discharge rate are independent of temperature and are not affected by the conductivity of the electrolyte.
In cases where ion diffusion in the bulk is essential, such as in secondary batteries, the storage capacity and charge/discharge rate are affected by temperature and the conductivity of the electrolyte.
The electrical conductivity of the electrolyte is a dominant factor in the internal resistance of the cell, and is therefore also an important factor in the electric double layer capacitor.

Asymmetric capacitors behave differently from symmetric capacitors. When charging, if activated carbon or a substance with similar functions to activated carbon is present in the negative electrode, positive ions are adsorbed onto its large surface, and electrons accumulate in the electrode to maintain electrical neutrality.

In symmetrical capacitors, the positive electrode contains activated carbon or a substance with similar functions to activated carbon, so anions are adsorbed onto the surface of the positive electrode, maintaining electrical neutrality and creating positive holes in the electrode.

In an asymmetric capacitor, if the positive electrode does not contain activated carbon or a substance with similar functions to activated carbon, it is impossible for anions to be adsorbed to the positive electrode in the same way as to the negative electrode. In order to maintain electrical neutrality between the negative and positive electrodes, the positive electrode must have a positive charge.

This means that the positive electrode is oxidized. Since there is no oxygen at the positive electrode and water does not break down, oxidation of the positive electrode means that electrons are removed from the positive electrode, creating holes.

However, unlike a normal oxidation reaction, no substance (ions) is transferred, only electrons. This can be called a redox capacitor, in which an oxidation reaction occurs at the positive electrode when the capacitor is charged.

When an iron (II) low-spin complex is present at the positive electrode, the iron (II) low-spin complex is oxidized to become an iron (III) low-spin complex. Both iron II and iron III low-spin complexes are octahedral complexes and undergo reversible oxidation-reduction reactions.

Between iron divalent and iron trivalent, the number of d electrons changes from 6 to 5, and when the two coexist in an aqueous solution, an electron exchange reaction occurs, causing the iron divalent to change to iron trivalent and the iron trivalent to change to iron divalent.
The redox potential is 0.36 V for the hexacyanoiron(II) complex and 1.06 V for the tris-1,10-phenanthrolineiron(II) complex.
When the applied voltage at the positive electrode exceeds the redox potential, the iron(II) complex is oxidized to the iron(III) complex, a reaction that is reversible and proceeds rapidly.
The redox reaction of tris-1,10-phenanthroline iron (II) complex, [Fe(II)(phen) ₃ ] ^2+, is shown below.
1,10-phenanthroline: phen
[Fe(II)(phen) ₃ ] ²⁺ ←→ [Fe(III)(phen) ₃ ] ³⁺ + e ^-

Low-spin iron complexes maintain an octahedral structure in the divalent and trivalent states, with little structural change. However, the number of counter ions (ClO ₄ ^- ) increases by one upon oxidation. In other words, to maintain electrical neutrality, ClO ₄ ^- migrates from the negative electrode to the positive electrode upon charging.

In an electric double layer capacitor that uses _NaClO4 as an electrolyte, Na ⁺ moves from the positive electrode to the negative electrode as it is charged. From the perspective of neutralization of the entire cell, the movement ^of _ClO4- from the negative electrode to the positive electrode and the movement of Na ⁺ from the positive electrode to the negative electrode are the same phenomenon.

When an iron(II) low-spin complex is mixed with the positive electrode, the iron(II) is oxidized to iron(III) when the applied voltage at the positive electrode exceeds the redox potential of the iron(II) complex.
During discharge, iron(III) is reduced to iron(II). This means that the device is a redox capacitor, as charging and discharging involve an oxidation-reduction reaction.

Incorporating high-spin iron(II) complexes into the positive electrode does not negate the redox effect, but many high-spin iron(II) complexes are not as stable as low-spin complexes.
It may be oxidized in air, so care must be taken when handling it. Iron(II) sulfate and iron(II) phosphate are stable, and iron(II) phosphate in particular is insoluble in water.
As described above, the iron complex has a good oxidation-reduction effect. The present invention relates to a battery using the iron complex in the positive electrode.

The electrolyte is divided into the very vicinity of the electrode (Helmholtz layer) and the bulk diffusion layer. Localization of ions due to charging is restricted to the vicinity of the Helmholtz layer. At this time, cations remain solvated (hydrated in aqueous systems) and adsorb to the negative electrode.

When a saturated aqueous solution of sodium perchlorate is used as the electrolyte, the structure in which water is adsorbed on the surface of the electrode as shown in Fig. 7(b) is not rational, because in this aqueous solution, the water molecules are bound by metal ions and there are almost no free water molecules.
As the cations are separated from the counter ions (ClO ₄ ⁻ ) and adsorbed onto the surface of the negative electrode, electrons accumulate at the negative electrode to maintain electrical neutrality.

At the positive electrode, positively charged vacancies (holes) with the same charge as the electrons adsorbed at the negative electrode are generated. The adsorption of ions due to charging occurs near the Helmholtz layer and is not affected by diffusion in the bulk layer.

It is reasonable to assume that the adsorption of cations is caused by electrostatic interactions between the electrode and ions. Because if ion diffusion is rate-limiting during charging and discharging, it must be affected by the conductivity and temperature of the electrolyte. In addition, it is not possible to apply the statistical mechanical Boltzmann distribution to the ion distribution near the electrode, because the Boltzmann distribution is a function of temperature.

In secondary batteries, the redox reaction involves mass transfer, so diffusion of ions in the bulk layer is essential. No matter how fast the redox reaction is, it is rate-limited by the diffusion rate and is therefore affected by the conductivity and temperature of the electrolyte.

In principle, the charging rate in a secondary battery is not faster than the diffusion rate. In an electric double layer capacitor, the charge and discharge rate is governed by the electrostatic interaction between the negative electrode and the cations, and the ionic radius and charge of the cations are important factors.
We compare the results of using saturated _LiClO4 and saturated _NaClO4 aqueous solutions as electrolytes for electric double layer capacitors.

The collecting electrode is titanium foil, and the active material is a mixture of activated carbon and graphite. The active material is formed on the titanium using coating or printing techniques. Needless to say, in addition to titanium foil, other metal foils and metal plates such as stainless steel foil, iron foil, and silver foil can also be used.

The only difference between the two capacitors is the cations Li ⁺ and Na ⁺ . Li ⁺ has a smaller ionic radius than Na ⁺ , but the hydration radius of Li ⁺ is larger. Both ^{Na +} and Li ⁺ are classified as hard acids, and strong electrostatic interactions are expected between the negative electrode and the negative electrode.

When ions are adsorbed on the electrode, they move with hydration, as shown in Fig. 7(a). Here, the molar concentration of the saturated _LiClO4 solution is 5.27m(mol/kg), and the molar concentration of the saturated NaClO4 solution is 17.1m.

Although the solubility of _LiClO4 in water is not high, its potential window is the same as that of a saturated _NaClO4 aqueous solution. This is also evidence of the strong hydration power of Li ⁺ . It is said that the binding of water extends to the second coordination sphere. The conductivity of a saturated _LiClO4 aqueous solution exceeds 200 mS/cm at 20°C, which is about twice as high as that of a saturated _NaClO4 aqueous solution.

Figure 8 shows the relationship between the ratio of activated carbon and energy density when saturated _NaClO4 aqueous solution and saturated _LiClO4 aqueous solution are used as the electrolyte. In both electrolytes, the energy density increases in proportion to the ratio of activated carbon.

As shown in Figure 8, the energy density value of the saturated _NaClO4 solution is slightly larger than that of the saturated _LiClO4 solution. This is believed to be due to the fact that the hydration radius of Li ⁺ is larger than that of Na ⁺ .

Therefore, Na ⁺ has a smaller ionic volume than Li ⁺ (Stokes radii of Na ⁺ and Li ⁺ are 1.84 and 2.38 Å, respectively), and as a result, more Na+ ions can be adsorbed onto the electrode, resulting in a larger charge storage capacity.

In this case, the molar concentration of the saturated _LiClO4 aqueous solution is relatively low at 5.27 m, but since the energy density and the activated carbon ratio are proportional, this means that the electrolyte is sufficiently concentrated.

The conductivity of a saturated _LiClO4 solution is twice as high as that of a saturated _NaClO4 solution. Nevertheless, the energy density of the former is lower than that of the latter, which supports the idea that conductivity does not affect the storage capacity.

Asymmetric capacitors have a different appearance from symmetric electric double layer capacitors. In Figure 10, the negative electrode is a mixture of graphite (containing acetylene black) and activated carbon, and the positive electrode is composed of only graphite (containing acetylene black).

The cell voltage during charging is about 3V. The cut-off voltage during discharging is changed from 2.5V to 3.2V. There is a large difference between the cut-off voltages of 3.2V and 2.7V during discharging. It can be seen that the storage capacity is very low below the cut-off voltage of 2.7V.
This means that the electrode surface area on the positive electrode where the anions, ClO ₄ ^{− ,} are adsorbed is small, and holes are unlikely to be generated in the electrode.

However, at a cut-off voltage of 3.2V, the discharge curve changes completely and the energy density becomes 20Wh/kg. This can be explained as follows. When the applied voltage exceeds the threshold value at the positive electrode, the graphite is oxidized. When we say oxidation, there is no oxygen at the positive electrode and water does not decompose. In the end, electrons are pulled out of the graphite and holes are created. In other words, the following oxidation reaction occurs at the positive electrode. C is graphite.
C → C ⁺ + e ^-
Although mass transfer is usually involved, here there is no mass transfer and only electron transfer occurs.
Another type of asymmetric capacitor is shown in Figure 11. Carbon cloth coated with _Fe2O3 provides an electrode with a large surface area _, similar to activated carbon.

In Fig. 11(a), both the positive and negative _electrodes are coated with _Fe2O3 . In Fig. 11(b), only the negative electrode is coated _{with Fe2O3} . The positive electrode is made of carbon cloth only.

As shown in Fig. 11(a), when carbon cloth coated _{with Fe2O3} is used as the negative and positive electrodes, an electric double layer capacitor that is comparable to activated carbon can be made. On the other hand, as shown in Fig. 11(b), when the negative _electrode is coated with _Fe2O3 and only carbon cloth is used as the positive electrode, the storage capacity is extremely reduced.
As in the embodiment of FIG. 11(a), it is preferable to use an electrode formed of carbon cloth or the like and coated with Fe ₂ O ₃ .

From the above results, it can be seen that the electric double layer capacitor is driven by the negative electrode, and if activated carbon or something with similar functions to activated carbon is present, ions are adsorbed there, and electrons accumulate at the negative electrode.

In the positive electrode, holes accumulate to maintain electrical neutrality throughout the cell. In asymmetric capacitors, if the positive electrode does not contain activated carbon or a material with similar functions to activated carbon, the positive electrode may become oxidized. In this case, the energy density is comparable to that of a symmetric electric double layer capacitor with activated carbon, and the discharge curve shows plateau characteristics like a secondary battery.

As an additive to the positive electrode, we assume that the additive is an iron(II) low-spin complex. The same applies to transition metal complexes other than iron. As mentioned at the beginning, when an iron(II) low-spin complex is oxidized, it becomes an iron(III) low-spin complex.

The redox potential is 0.36 V for the hexacyanoiron(II) complex and 1.06 V for the tris-1,10-phenanthrolineiron(II) complex. When the applied voltage at the positive electrode exceeds the redox potential, the iron(II) complex is oxidized to the iron(III) complex.

This reaction is known to be reversible and proceeds rapidly. The redox reaction of tris-1,10-phenanthroline iron (II) complex, [Fe(II)(phen) ₃ ] ²⁺ , is shown below.
Here, phen: 1,10-phenanthroline.
[Fe(II)(phen) ₃ ] ²⁺ ←→ [Fe(III)(phen) ₃ ] ³⁺ + e ^-

Low-spin iron complexes maintain an octahedral structure in the divalent and trivalent states, with little structural change. However, the number of counter ions (ClO ₄ ^- ) increases by one upon oxidation. In other words, to maintain electrical neutrality, ClO ₄ ^- migrates from the negative electrode to the positive electrode upon charging.

In electric double layer capacitors, ions also move throughout the cell. For example, when _NaClO4 is used as the electrolyte, Na ⁺ moves from the positive electrode to the negative electrode as the battery is charged. The difference from secondary batteries is that in electric double layer capacitors, the movement of ions is not the rate-limiting step. From the perspective of neutralization of the entire cell, the movement ^of _ClO4- from the negative electrode to the positive electrode and the movement of Na ⁺ from the positive electrode to the negative electrode are the same phenomenon.

From the viewpoint of practical application of asymmetric capacitors, it is desirable that the oxidation reaction at the positive electrode due to charging occurs at a cell voltage of 2 to 2.5 V. There are many iron(II) low-spin complexes, so one can simply select one that satisfies the above conditions.
Low-spin iron(II) complexes include naturally occurring complexes: iron(II) porphyrin complexes can be isolated from mammalian blood.
Assuming that general-purpose activated carbon or inexpensive metal compounds are used as the active material, and taking long-term stability into consideration, the cut-off voltage is set to 2.5 to 2.7 V.

In Figure 9, when the ratio of graphite to activated carbon in the electrode is changed, the energy density increases in proportion to the ratio of activated carbon. This means that the ion concentration is high enough, and the adsorbed ion concentration increases with increasing activated carbon. In the graphite and activated carbon mixture, the activated carbon content is limited to 70%, but in the activated carbon and acetylene black mixture, the activated carbon content can be increased to 90%. In that case, the energy density exceeds 30Wh/kg.
Based on the results so far, it has been shown that by using activated carbon as an electrode, an energy density of 30Wh/kg can be achieved in an aqueous electric double layer capacitor.

Below, the capacitor battery (electric double layer capacitor battery) of the present invention is illustrated as being configured as a lithium ion secondary battery, and the structures of the capacitor battery and secondary battery according to the embodiment are described with reference to the drawings. Figure 1 is a cross-sectional view showing an example of a capacitor battery.

In FIG. 1, a coin-type lithium ion secondary battery is illustrated as an example, but the technical concept of the present invention is not limited to this. For example, it goes without saying that the battery may be cylindrical, as shown in FIG. 2. Other examples include a film shape and a box shape.

As shown in FIG. 1, in a lithium ion secondary battery as an example of a capacitor battery of the present invention, a positive electrode material 221 is formed or disposed on a conductor forming a positive electrode 205. A negative electrode material 231 is formed or disposed on a conductor forming a negative electrode 206. A separator 204 is disposed between the positive electrode material 221 and the negative electrode material 231, and the separator 204 is filled, permeated, or impregnated with an electrolyte 222.

Although omitted in FIG. 1, a positive electrode terminal 202 is connected to the positive electrode 205, and a negative electrode terminal 203 is connected to the negative electrode 206. The positive electrode 205 and the negative electrode 206 are insulated from each other by a gasket 207.

The positive electrode is composed of a positive electrode material 221 that is located on and connected to the inner surface of the positive electrode 205, the negative electrode is positioned facing the positive electrode material 221, and a separator 204 is placed between the positive electrode and the negative electrode.

A material containing cobalt is used as the positive electrode material 221. For example, a mixture of graphite and lithium cobalt oxide (LiCoO ₂ ) may be used. The content ratio of the graphite to the mixed material is preferably in the range of 1:0.8 to 1:1.5.

Other examples include a mixture of graphite and cobalt ( _LiCoO2 ), a mixture of graphite and manganese _{( LiMn2O4} ), a mixture of graphite and nickel ( _LiNiO2 ), a mixture of graphite and iron phosphate (LiFePO4), _and a mixture of graphite and iron oxide ( _Fe2O , _Fe2O3 ) _. Carbon quantum dots (CQDs) are also examples.
As described above, in addition to lithium cobalt oxide, lithium manganate, lithium iron phosphate, and the like can be used for the positive electrode.

As explained in Fig. 11, at least one of the positive electrode and the negative _electrode is coated with _Fe2O3 . Preferably, both the positive electrode and the negative _electrode are coated with _Fe2O3 .

The mixture such as _LiCoO2 may be any oxide as long as it does not undergo structural changes when oxidized. It is not limited to graphite, and carbon materials such as graphite and coke can be used.

A mixture of graphite and a material using cobalt (LiCoO ₂ ) may be used. The content ratio of the graphite to the material to be mixed is preferably in the range of 1:0.8 to 1:1.5.

The material to be mixed with graphite is not limited to oxide materials. For example, a mixture of graphite and a material using an iron phenanthroline complex ([Fe(phen) ₃ ](ClO ₄ ) ₂ ) or a mixture of graphite and a material using an iron cyano complex (Li ₄ [Fe(CN) ₆ ]) can be used.

The ligand of the iron(II) complex is not limited to phenanthroline, but may be one that forms a low-spin complex such as bipyridine. Other examples include a mixture of materials using graphite and nickel hydroxide (Ni(OH) ₂ ).

The negative electrode is composed of a negative electrode material 231 located and connected to the inner surface of the negative electrode 206. Examples of the negative electrode material 231 include graphite (LiC ₆ ), hard carbon (LiC ₆ ), titanate (Li ₄ Ti ₅ O ₁₂ ), and lithium titanate (LTO).

The separator 204 is impregnated with an aqueous solution of a perchlorate such as lithium perchlorate (LiClO ₄ ). The aqueous solution of the perchlorate is preferably a saturated aqueous solution of perchlorate, but there is no difference in performance or efficiency even if the aqueous solution is close to a saturated state. It is sufficient if the aqueous solution is 95% or more saturated. More preferably, it is 98% or more saturated.

The negative electrode 206 is inserted into the positive electrode 205 with its bottom end and both sides wrapped in a gasket 207, and the negative electrode 206 is fixed to the positive electrode 205 by crimping, and is insulated from the negative electrode 206 and the positive electrode 205 by the gasket 207.

Figure 6 is an explanatory diagram explaining the charging and discharging operation of the electric double layer capacitor battery of the present invention. In Figure 6, Figure 6 (a) is an explanatory diagram of the operation when the electric double layer capacitor battery is being charged by the charger 101, and Figure 6 (b) is an explanatory diagram of the operation when discharging to a load device such as a mobile device 102.

Electric double layer capacitor batteries are generated by the localization of ions dissolved in the electrolyte. That is, when a voltage is applied to the solution, positive ions localize at the negative electrode and negative ions localize at the positive electrode. To maintain electrical neutrality, electrons are adsorbed to the negative electrode, and positively charged vacancies are created at the positive electrode.

As shown in Fig. 6(a), when a voltage is applied to a Li-ion battery, cobalt is partially oxidized from trivalent ( _LiCoO2 ) to tetravalent ( _CoO2 ) in the positive electrode, as shown in the formula below. Partial is expressed by x < 1.
LiCoO ₂ ←→ Li _(1-x) CoO ₂ + xLi ⁺ + xe ^-positive electrode (Formula 1)
6xC + xLi ⁺ + xe ^- ←→ xC ₆ Li negative electrode (Formula 2)

Meanwhile, at the negative electrode, lithium ions are intercalated into the graphite and partially reduced, that is, Li+ released at the positive electrode is reduced to C ₆ Li at the negative electrode.

In this case, the redox potential of the intercalated C ₆ Li (C ₆ Li / Li ⁺ = 2.90) is lower than that of elemental Li (Li / Li ⁺ = 3.05). Since the potential at the positive electrode (reaction 1) is 0.90 V, adding (equation 1) and (equation 2) results in an electromotive force of 3.8 V for the total reaction (battery). However, the electromotive force changes depending on the value of x. In fact, Toshiba's aqueous lithium-ion battery operates at 2.4 V.

In an electric double-layer capacitor battery using graphite as the negative electrode, there is nothing to oxidize at the positive electrode, and positively charged vacancies are generated to maintain electrical neutrality. At the negative electrode, Li ⁺ is not reduced but simply localized in the electrode.

If the positive electrode contains a substance that can be oxidized, such as LiCoO2, at a certain voltage (exceeding the electromotive force), the Li ⁺ in the negative electrode intercalates into the graphite to produce _C6Li . In other words, Li ⁺ is reduced. In this case, the same phenomenon occurs as in the negative electrode of a lithium-ion battery.
In other words, the only difference between the lithium ion battery and the electric double layer capacitor battery of the present invention is the mixture of the positive electrode.

When a voltage is applied as shown in Figure 6 (a), charging begins as the voltage rises. Initially, all charging is done by the electric double-layer capacitor battery. When the voltage exceeds 2V and a certain voltage (electromotive force), an oxidation-reduction reaction similar to that of a lithium-ion battery occurs. The cut-off voltage is set to 2.7V. This can be said to be a new concept of energy storage device that combines an oxidation-reduction reaction with an electric double-layer capacitor battery.

When a large current is applied, the redox reaction cannot keep up, and only the electric double-layer capacitor battery functions. When a small current is applied for a long time, the redox reaction occurs at a voltage that exceeds the electromotive force, and the overall energy density increases significantly.

For example, in the electric double-layer capacitor battery we developed, a charge/discharge capacity of 0.03 mAh/ ^cm2 was obtained at a current density of 20 mA/ ^cm2 (Coulombic efficiency is nearly 100%). This means that it can be fully charged in 5.4 seconds and a charge capacity of 0.03 mAh/ ^cm2 can be obtained.

In 5.4 seconds, the secondary battery (redox reaction) barely responds, and only the electric double layer capacitor functions during rapid charging. On the other hand, when charging for a long time at a low current density, for example when the current density is 1/10 or less, the secondary battery (redox reaction) begins to function.

At the negative electrode, Li ⁺ intercalates into graphite to form _C6Li , which is partially reduced. At the positive electrode, for example, _LiCoO2 is partially oxidized to Li _{(1-x) CoO2} . If [Fe(phen) ₃ ]( _ClO4 ) ₂ is present at the positive electrode, it is oxidized to [Fe(phen) ₃ ]( _ClO4 ) ₃ . That is, iron is oxidized from divalent to trivalent.

The above-mentioned power storage method is only possible with aqueous electrolytes that have a wide potential window. If the potential window of the electrolyte is narrow, the applied voltage cannot be increased and the redox reaction does not occur. In other words, it does not function as a secondary battery. It is essentially different from the redox capacitors reported so far. Similarly, it can also be done with organic electrolytes, but the storage capacity of an electric double layer capacitor with organic electrolytes is only a few percent of that of a secondary battery, which is almost within the margin of error.

Secondary batteries convert the redox reaction that occurs at the negative and positive electrodes into electrical energy. The role of the electrolyte is to enable the movement of electrons and ions between the negative and positive electrodes.

A saturated lithium perchlorate aqueous solution with a potential window of 3 V or more can be used as an electrolyte for lithium-ion batteries. Even if it is not saturated, a concentrated aqueous solution close to saturation has a wide potential window and can therefore be used as an electrolyte for secondary batteries.

In order to use a saturated aqueous perchlorate solution as the electrolyte for a secondary battery, the electromotive force of the secondary battery must be smaller than the potential window of the electrolyte, since the potential window of the electrolyte is specific.

A solid electrolyte may be used for the separator 204. The solid electrolyte suppresses the movement of ions between the negative and positive electrodes, and is applied independently to each electrode, i.e., the negative and positive electrodes, so that the reduction potential at the negative electrode and the oxidation potential at the positive electrode can be kept low during charging.

This makes it possible to use aqueous solutions with narrow potential windows as electrolytes. A saturated aqueous solution of lithium perchlorate has a wider potential window (3.2 V at 25°C) than other aqueous solutions, making it a preferable electrolyte.

The present invention has a wide potential window, allowing stable long-term use. Similarly, a saturated aqueous sodium perchlorate solution can be used as the electrolyte in sodium ion batteries.

Saturated perchlorate solutions include lithium perchlorate (LiClO ₄ ), sodium perchlorate (NaClO ₄ ), barium perchlorate (Ba(ClO ₄ ) ₂ ), and magnesium perchlorate (Mg(ClO4) ₂ ). These saturated perchlorate solutions are used as electrolytes in secondary batteries.

In the examples of the present invention, a saturated aqueous perchlorate solution is used as the electrolyte, but this is not limited to being saturated. Even if the aqueous perchlorate solution is close to being saturated, there is no significant difference in effect, capacity, or performance. Therefore, it goes without saying that an aqueous perchlorate solution may be used.

Figures 1 and 2 are perspective views and partial cross-sectional views of the electric double layer capacitor battery (secondary battery) of the present invention. This is an embodiment in which the electric double layer capacitor battery (secondary battery) of the present invention is configured in a cylindrical shape. Note that, for ease of illustration, the positive electrode 205, the negative electrode 206, etc. are omitted. It goes without saying that the electric double layer capacitor battery (secondary battery) of the present invention can be configured in a wide variety of other shapes, such as a box shape or a plate shape.

As shown in Figures 1 and 2, the electric double layer capacitor battery (secondary battery) of the present invention is configured such that a positive electrode material 221, a negative electrode material 231, and a separator 204 are contained in a container 107, and an insulating film 108 is disposed between the positive electrode material 221, the negative electrode material 231, the separator 204, etc., as necessary.
An electrolyte solution 222 is filled between the separator 204 , the positive electrode material 221 , and the negative electrode material 231 , and the electrolyte solution 222 is filled between the positive electrode material 221 and the negative electrode material 231 .
3 is an explanatory diagram of a cyclic voltammogram (CV) of a saturated aqueous solution of perchlorate. An Ag/AgCl electrode was used as the reference electrode.
In the CV measurement shown in Figure 3, no current flows in the flat areas. This means that the water decomposition reaction is not occurring. The flat areas are potential windows.

The potential window is 3.2 V for saturated sodium perchlorate and saturated lithium perchlorate aqueous solutions, and it can be seen that saturated magnesium perchlorate, saturated perchlorate aqueous solution, and saturated barium perchlorate aqueous solution also have a wide potential window (about 3 V).

This means that saturated aqueous solutions of lithium perchlorate (LiClO ₄ ), sodium perchlorate (NaClO ₄ ), barium perchlorate (Ba(ClO ₄ ) ₂ ) and magnesium perchlorate (Mg(ClO4) ₂ ) can be used as electrolytes in secondary batteries.
As shown in Figure 3, saturated aqueous solutions of perchlorate have a wide potential window. If these aqueous solutions are used as electrolytes, it is possible to operate at high applied voltages.

4 is an explanatory diagram of the cyclic voltammogram (CV) and temperature change of a saturated aqueous solution of lithium perchlorate. An Ag/AgCl electrode is used as the reference electrode.
Since CV depends on temperature, the potential window also changes with temperature. It is 3.2 V at 25°C, but decreases to 3.0 V at 40°C and 2.8 V at 60°C.

In Figure 4, the solution is saturated at 25°C, but as the temperature rises, the solubility of lithium perchlorate increases, so at 40°C and 60°C, the solution is not saturated but is concentrated and close to saturated.

In Figure 4, a wide potential window is maintained at 40°C and 60°C. In other words, even in a concentrated aqueous solution close to saturation, the potential window is wide, and it can be used as an electrolyte for secondary batteries.

Aqueous solutions other than lithium perchlorate ( _LiClO4 ) can also be used as the electrolyte, such as aqueous solutions of perchlorates such as sodium perchlorate ( _NaClO4 ), magnesium perchlorate (Mg( _ClO4 ) ₂ ), calcium perchlorate (Ca( _ClO4 ) ₂ ), barium perchlorate (Ba( _ClO4 ) ₂ ) or aluminum perchlorate (Al( _ClO4 ) ₃ ).
FIG. 5 is an explanatory diagram of the conductivity of a saturated aqueous lithium perchlorate solution and its temperature change.
The conductivity of a saturated aqueous solution of lithium perchlorate is more than twice as high as that of a saturated aqueous solution of sodium perchlorate. In either case, the conductivity increases with increasing temperature.

In Figure 5, the horizontal axis of the graph is temperature, and the vertical axis is conductivity in millisiemens per centimeter (mS/cm). The conductivity of a lithium perchlorate ( _LiClO4 ) solution is about twice as high as that of a saturated _NaClO4 solution, making the saturated _LiClO4 solution an excellent electrolyte.

As a result of the above, when a saturated aqueous solution of lithium perchlorate (LiClO ₄ ) is used as the electrolyte, a maximum applied voltage of 3.2 V is possible at 25°C, and a voltage of 2.8 V is possible even at 60°C.

The electrical conductivity of an aqueous solution of lithium perchlorate (LiClO ₄ ) is higher than that of an aqueous solution of sodium perchlorate (NaClO ₄ ), and is therefore preferable as an electrolyte for electric double layer capacitor batteries (secondary batteries).

Water forms large cluster-like structures through hydrogen bonds. These cluster structures weaken the bonds of water, narrowing the potential window as a result. Conversely, it is assumed that independent H ₂ O would have a wider potential window. This is made possible by ultra-concentrated aqueous solutions.

The weight concentration of a saturated aqueous solution of sodium perchlorate is extremely high (17.1 mol/(1 kg of water) at 25°C), and it is assumed that the water cluster structure is almost completely destroyed.

A mixture of two or more of the above-mentioned saturated aqueous solutions of sodium perchlorate, lithium perchlorate, magnesium perchlorate, calcium perchlorate, barium perchlorate, aluminum perchlorate, magnesium sulfate, potassium sulfate, and sodium sulfate can also be used as the electrolyte.

The mixture is not limited to a combination of two types of saturated aqueous solutions, such as a mixture of a saturated aqueous solution of sodium perchlorate and a saturated aqueous solution of lithium perchlorate, but may also be a mixture of three or more types of saturated aqueous solutions, such as a mixture of a saturated aqueous solution of sodium perchlorate, a saturated aqueous solution of lithium perchlorate, and a saturated aqueous solution of barium perchlorate.
Such a mixture does not necessarily have to contain an aqueous solution of lithium perchlorate, and a mixture of various combinations can be used as the electrolyte.

Although it has been stated that a saturated aqueous solution of lithium perchlorate or a concentrated aqueous solution of lithium perchlorate close to saturation is used as the electrolyte for lithium ion batteries, it is also within the technical scope of this invention to use a saturated aqueous solution of sodium perchlorate as the electrolyte for sodium ion batteries, just as in lithium ion batteries.

Other embodiments of the present invention will be described below. Details that are the same as or similar to those previously described may be omitted. In addition, the embodiments described in this specification and drawings may be combined in part or in whole.

Figure 12 is a diagram of the structure and explanation of a battery in another embodiment of the present invention. In the embodiment of Figures 1 and 2, the negative electrode material 231 and the positive electrode material 221 are arranged in a position facing the separator 204.

In the embodiment of the present invention shown in FIG. 12, negative electrode material 231 and positive electrode material 221 are alternately arranged or formed adjacent to each other on a substrate or film (sheet) (hereinafter referred to as substrate (film)) 301a. An electrolyte solution 222 is filled around the negative electrode material 231 and the positive electrode material 221.

Also, the positive electrode material 221 and the negative electrode material 231 are arranged or formed adjacent to each other alternately on the substrate (film) 301b. The positive electrode material 221 and the negative electrode material 231 are surrounded by an electrolyte solution 222.

The positive electrode material 221 of the substrate (film) 301a is disposed opposite the positive electrode material 221 of the substrate (film) 301b. The negative electrode material 231 of the substrate (film) 301a is disposed opposite the negative electrode material 231 of the substrate (film) 301b. A separator 204 is disposed between the substrate (film) 301a and the substrate (film) 301b, and the separator 204 is attached to a gasket 207. An electrolyte 222 is filled around the substrate (film) 301a, the substrate (film) 301b, and the separator 204.

A positive electrode material 221 of the substrate (film) 301b is arranged or formed at a position facing the positive electrode material 221 of the substrate (film) 301a, and a negative electrode material 231 of the substrate (film) 301b is arranged or formed at a position facing the negative electrode material 231 of the substrate (film) 301a.
In FIG. 1, the separator 204 functions as an electrolytic membrane, but also has the function of preventing the negative electrode material 231 and the positive electrode material 221 from contacting each other.

In the embodiment of Figure 12, the positive electrode material 221 of the substrate (film) 301b is arranged or formed at a position facing the positive electrode material 221 of the substrate (film) 301a, so there is no separator 204a, and even if the positive electrode material 221 of the substrate (film) 301a and the positive electrode material 221 of the substrate (film) 301b come into contact with each other, no electrical short circuit occurs.
In addition, since the battery is composed of the electrolyte 222 and the adjacent cathode material 221 and anode material 231, the efficiency is good.
The positive electrode material 221 of each substrate (film) 301 functions as a positive electrode, the negative electrode material 231 functions as a negative electrode, and the electrolyte solution 222 functions to form a battery.

The negative electrode material 231 and the positive electrode material 221 are disposed or formed on one side of the substrate (film) 301a and the substrate (film) 301d. The negative electrode material 231 and the positive electrode material 221 are disposed or formed on both sides of the substrate (film) 301b and the substrate (film) 301c.

Both ends of each substrate (film) 301 are sealed with gaskets 207, and each separator 204 (separator 204a, separator 204b, separator 204c) is disposed to prevent the opposing electrode materials from contacting each other.
Substrate (film) 301a, substrate (film) 301b, substrate (film) 301c,
The substrate (film) 301 d is held in a container 107 .
The power capacity can be increased by stacking multiple substrates (films) 301 .

Figure 13 is a diagram of the structure and an explanatory diagram of a battery in another embodiment of the present invention. In Figure 13, the negative electrode material 231 is coated with a negative electrode coating material 303, and the positive electrode material 221 is coated with a positive electrode coating material 302.

As explained in FIG. 11, when an electrode material made of or formed from carbon cloth or the like is coated with Fe ₂ O ₃ , an electrode with a large surface area like activated carbon is obtained.
In Fig. 11(a), both the positive and negative _electrodes are coated with _Fe2O3 , while in Fig. 11(b), only the negative _electrode is coated with _Fe2O3 .

13, by coating the positive electrode material 221 with an _iron oxide material such as _Fe2O3 as a positive electrode coating material 302 and coating the negative electrode material 231 with an _iron oxide material such as _Fe2O3 as a negative electrode coating material 303, an electrode with a large surface area like activated carbon is obtained, and the battery efficiency is improved. Note that the electrode may be coated with a coating material on either the positive electrode material 221 or the negative electrode material 231.
As in the embodiment of FIG. 13, it is preferable to use an electrode formed of carbon cloth or the like and coated with Fe ₂ O ₃ .

As shown in Figures 12 and 13, by arranging electrodes of the same polarity in opposing positions, the battery functions even if the opposing electrodes (for example, the positive electrode material 221 of the substrate (film) 301a and the positive electrode material 221 of the substrate (film) 301b) are positively charged. Therefore, the separator 204 used to prevent contact between the electrode materials is not necessary. It goes without saying that the separator 204 may also be used in the configuration of Figure 13. Figures 14 and 15 are diagrams and explanatory diagrams of the configuration of a battery in another embodiment of the present invention. They mainly show the state when the separator 204 is not configured or arranged.

14 is an explanatory diagram of the arrangement of the positive electrode material 221 and the negative electrode material 231. The positive electrode material 221 and the negative electrode material 231 are formed in a comb-like shape and are arranged with a gap therebetween. A gasket 207 is arranged around the electrode materials, and an electrolyte 222 is filled in the gasket 207.
One end of the positive electrode material 221 is connected to an electrode terminal 304a for applying a positive potential, and one end of the negative electrode material 231 is connected to an electrode terminal 304b for applying a negative potential.
A battery or the like is constituted by a positive electrode material 221 formed in a comb-like shape, a negative electrode material 231 formed in a comb-like shape, and a filled electrolyte solution 222.

By arranging or forming the positive electrode material 221 and the negative electrode material 231 adjacent to each other on the substrate (film) 301a, the separator 204 is unnecessary. By forming them in a comb-tooth shape, the area where the positive electrode material 221 and the negative electrode material 231 are adjacent to each other is increased, and good current capacity can be achieved.

In addition, in FIG. 14 and other figures, the electrode material is illustrated as having a comb-like shape, but this is not limited thereto, and any configuration may be used as long as the positive electrode material 221 and the negative electrode material 231 are arranged or formed so as to be adjacent to each other on one plane.

Figure 15 is a cross-sectional view taken along line AA' in Figure 14. Figure 15(a) shows an embodiment in which a positive electrode material (positive electrode) and a negative electrode material (negative electrode) are formed or configured on substrate 301a. Figure 15(b) shows an embodiment in which a positive electrode material (positive electrode) and a negative electrode material (negative electrode) are formed or configured on substrates 301a and 301b.

In FIG. 15(a), a filling hole (inlet/outlet hole) 305 for the electrolyte 222 is formed in the substrate 301b. The electrolyte can be injected from the inlet/outlet hole 305a, and the electrolyte can be discharged from the inlet/outlet hole 305b. Therefore, the electrolyte 222 can be replaced.

The electrolyte 222 deteriorates with use of the battery. Therefore, it is preferable to replace the electrolyte 222 at a certain level. In addition, the battery can be manufactured more easily if the electrolyte is injected after assembling the substrates 301a and 301b with the gasket 207.

Inlet/outlet holes 305 may be formed or placed on both substrates 301a and 301b. In addition, inlet/outlet holes (not shown) for electrolyte 222 etc. may be formed in gasket 207, container 107 etc., and electrolyte 222 may be injected and poured out from these inlet/outlet holes (not shown). Also, electrolyte 222 may be constantly injected from inlet/outlet hole 305a and poured out from inlet/outlet hole 305b, allowing the electrolyte 222 to circulate.

15(b) and the like, it is preferable to arrange the positive electrode material 221 of the substrate 301a and the positive electrode material 221 of the substrate 301b in opposing positions, and the negative electrode material 231 of the substrate 301a and the negative electrode material 231 of the substrate 301b in opposing positions. This is because there are few problems in terms of the operation of the battery even if the substrates 301a and 301b are deformed by external pressure or the like, and the positive electrode material 221 of the substrate 301a comes into contact with the positive electrode material 221 of the substrate 301b, and also the negative electrode material 231 of the substrate 301a comes into contact with the negative electrode material 231 of the substrate 301b.
14 and 15 show a configuration in which a positive electrode material 221 and a negative electrode material 231 are disposed or formed adjacent to each other on a flat surface of a substrate 301.

Figure 16 shows a configuration in which a step t is formed in the substrate 301a. The step t is created by forming a protrusion 307. The protrusion 307 may be formed by using a resin or the like on the substrate 301a, or may be formed by cutting the substrate 301a into a groove shape.

In the embodiment of FIG. 16, the positive electrode material 221 is formed on the convex portion 307, and the negative electrode material 231 is formed on the concave portion 308. The positions of the positive electrode material 221 and the negative electrode material 231 may be reversed. For example, the negative electrode material 231 is formed on the convex portion 307, and the positive electrode material 221 is formed on the concave portion 308.

The step t is determined by the film thickness of the positive electrode material 221 and the negative electrode material 231. If the film thickness of the positive electrode material 221 or the negative electrode material 231 is a, then the film is formed so that the relationship t > a is satisfied, and more preferably, the relationship 2t > a is satisfied.

16, a positive electrode material 221 and a negative electrode material 231 are formed on a substrate 301a having projections and recesses, and an electrolyte solution 222 is filled between the substrates 301b and 301a. The positive electrode material 221, the negative electrode material 231, and the electrolyte solution 222 therebetween constitute a capacitor battery or the like.
In the battery manufacturing method of the present invention, the positive electrode material 221 and the negative electrode material 231 are formed by a deposition technique and a sputtering technique.

Figures 17, 18, 19, and 20 are explanatory diagrams of the manufacturing method of the present invention for batteries, etc. Figure 17(a) is a plan view of substrate 301a, and Figure 17(b) is a cross-sectional view taken along line AA' in Figure 17(a).

A step t is formed in the substrate 301a. The protrusion 307 may be formed by using a resin or the like on the substrate 301a. The recess 308 may be formed by cutting the substrate 301a into a groove shape.

As shown in FIG. 17(a), comb-shaped recesses 308 and protrusions 307 are formed on substrate 301a, and electrode terminal 304a for applying a negative voltage is disposed on one end of recess 308, and electrode terminal 304b for applying a positive voltage is disposed on one end of recess 308. Note that the shape is not limited to comb-shaped, and it is sufficient that at least one pair of protrusions 307 and recesses 308 are formed.

Figure 18 shows an example in which a film 306 is formed on a substrate 301a by a deposition technique (deposition film formation). Note that this is not limited to deposition techniques (deposition film formation), and sputtering film formation may also be used. It goes without saying that the film 306 may also be formed or configured by using ion plating or chemical vapor deposition (CVD).

The deposition material 309 (positive electrode material 221, negative electrode material 231) is evaporated from the evaporation source, and the film 306 on the substrate 301a arranged above is deposited. The film 306a becomes the positive electrode material 221, and the film 306b becomes the negative electrode material 231.

The positive electrode material 221 and the negative electrode material 231 are formed from the same deposition material 309, but because of the step t, the deposition film 306 is "cut at the film step" and separated into deposition film 306a and deposition film 306b.

The deposited film 306a formed on the convex portion 307 becomes the positive electrode material 221, and the deposited film 306b formed on the concave portion 308 becomes the negative electrode material 231. Therefore, in one deposition process, the step t allows the positive electrode material 221 and the negative electrode material 231 to be formed or configured simultaneously. Furthermore, the step t allows the positive electrode material 221 and the negative electrode material 231 to be formed in a comb-like shape, as shown in FIG. 17(a). In addition, the electrode terminal 304a and the electrode terminal 304b can be formed from the deposited material 309.

As described in Figure 11 _etc. , when the positive electrode material 221 and the negative electrode material 231 are coated with iron oxide (e.g., _Fe2O3 ), after forming the vapor deposition film 306 (vapor deposition film 306a, vapor deposition film 306b), iron oxide (e.g., _Fe2O3 ) is used as the vapor deposition material 309 to form iron oxide (e.g., _Fe2O3 ) on the vapor deposition film 306 (vapor deposition film 306a, vapor deposition film _{306b )} .
The deposition material 309 for the electrode terminals 304a and 304b is preferably formed into a plated film by a plating technique such as Ni plating or Cu plating.

The embodiment of the manufacturing method of the present invention shown in Fig. 18 is an embodiment in which the positive electrode material 221 and the negative electrode material 231 are formed of the same material. The manufacturing method of the present invention shown in Fig. 19 is an embodiment in which the positive electrode material 221 and the negative electrode material 231 are formed of different materials.
In order to change or modify the forming materials of the positive electrode material 221 and the negative electrode material 231, a deposition mask 310 is used.

As shown in FIG. 19(a), a deposition mask 310a having an opening in the recess 308 is placed under the substrate 301a. The deposition material 309 passes through the opening of the deposition mask 310a and is deposited as a deposition film 306b on the recess 308 of the substrate 301a. The deposition film 306b becomes the negative electrode material 231. The deposition mask 310a may be placed in the opposite manner. A deposition mask 310a having an opening in the protrusion 307 is placed under the substrate 301a. The deposition material 309 passes through the opening of the deposition mask 310a and is deposited as a deposition film 306b on the protrusion 307 of the substrate 301a.

As shown in FIG. 19(b), a deposition mask 310b having an opening in the convex portion 307 is placed under the substrate 301a. The deposition material 309 passes through the opening of the deposition mask 310b and is deposited as a deposition film 306a on the convex portion 307 of the substrate 301a. The deposition film 306a becomes the positive electrode material 221. The deposition mask 306 may be positioned in the reversed position as described above.

In the embodiment of FIG. 19, the deposition mask 310a used to form the positive electrode material 221 and the deposition mask 310b used to form the negative electrode material 231 are used, so that the positive electrode material 221 and the negative electrode material 231 can be formed from different materials.

As shown in Fig. 20, when one of the positive electrode material 221 and the negative electrode material 231 is formed and the electrode material is coated with iron oxide (e.g., _Fe2O3 ) as described in Fig. ₁₁ etc., a vapor deposition film 306 (vapor deposition film 306a or 306b) is formed. Next, iron oxide (e.g., _Fe2O3 ) is used as the vapor deposition material 309 to form iron oxide (e.g., _Fe2O3 ) on the vapor deposition film 306 (vapor deposition film 306a or _306b ) _.
In order to form one of the positive electrode material 221 and the negative electrode material 231, a deposition mask 310 is used.

As shown in FIG. 20(a), a deposition mask 310 having openings in the recessed portions 308 is placed under the substrate 301. The deposition material 309 passes through the openings of the deposition mask 310 and is deposited as a deposition film 306b on the recessed portions 308 of the substrate 301a. The position of the deposition mask 310 may be reversed. A deposition mask 310 having openings in the protruding portions 307 is placed under the substrate 301. The deposition material 309 passes through the openings of the deposition mask 310 and is deposited as a deposition film 306b on the protruding portions 307 of the substrate 301a.

As shown in FIG. 20B, no deposition mask 310 is used, and iron oxide (for example, Fe ₂ O ₃ ) is used as the deposition material 309 to form iron oxide (for example, Fe ₂ O ₃ ) on the deposition film 306 b .

20, a deposition mask 310 is used to form the negative electrode material 231. Also, iron oxide (for example, Fe ₂ O ₃ ) can be formed so as to cover the entire substrate 301a.

The above embodiment is an embodiment in which the positive electrode material 221 and the negative electrode material 231 are arranged in a comb-like shape. The present invention is not limited to this. For example, as shown in FIG. 21, they may be formed in a spiral or helical shape. In other words, the present invention may have any configuration or structure as long as a positive electrode made of the positive electrode material 221 and a negative electrode made of the negative electrode material 231 are formed adjacent to one substrate or film, and the electrolyte solution 222 is filled between the positive electrode material 221 and the negative electrode material 231.

The above examples are examples in which the adjacent positive electrode made of positive electrode material 221 and the negative electrode made of negative electrode material 231 are fixed in position, but the present invention is not limited to this.

Figure 22 is a diagram of the configuration and an explanatory diagram of the battery of the present invention. In Figure 22, a positive electrode made of a positive electrode material 221 is arranged in a container 107 so that it can rotate in the L direction around a central position C. Also, a negative electrode made of a negative electrode material 231 is arranged in a container 107 so that it can rotate in the R direction around a central position C. The container 107 is filled with an electrolyte 222.

The positive electrode made of the positive electrode material 221 rotates around the center position C, and the negative electrode made of the negative electrode material 231 rotates around the center position C. With the rotation, the positional relationship between the positive electrode and the negative electrode changes, and the electrolyte solution 222 is agitated.

22, as shown in FIG. 15(a), a filling hole (inlet/outlet hole) 305 (not shown) for the electrolyte 222 may be formed or disposed in the container 107. The electrolyte can be injected from the inlet/outlet hole 305, and the electrolyte can be discharged from the inlet/outlet hole 305. Therefore, the electrolyte 222 can be replaced.
The state of charge or discharge may be monitored, and the flow rate or movement of the electrolyte may be changed or adjusted according to the state of charge or discharge.
By injecting and discharging the electrolyte through the inlet/outlet hole 305, the electrolyte can be moved and stirred, and the charging and discharging conditions can be improved.

In FIG. 22, the positive electrode made of the positive electrode material 221 is arranged and configured so that it can rotate in the L direction, and the negative electrode made of the negative electrode material 231 is arranged and configured so that it can rotate in the R direction, but this is not limited to this. The rotation direction of the positive electrode made of the positive electrode material 221 and the rotation direction of the negative electrode material 231 may be the same. The rotation direction of the positive electrode made of the positive electrode material 221 and the rotation direction of the negative electrode material 231 may be synchronized and rotated while maintaining the positional relationship. By maintaining the positional relationship, the charging or discharging state of the battery can be kept constant, and the electrolyte can be stirred.

The above points also apply to other embodiments. In addition, it is not limited to rotation, and for example, in the embodiment of FIG. 21, it may be rotated around center O. In addition, it is not limited to rotation, and it may be vibrated. For example, in the embodiment of FIG. 16, the electrolyte can be stirred by moving or vibrating the substrate (film, sheet) 301a in the vertical or horizontal directions. The vibration may be vibration or movement caused by ultrasonic waves, etc.

In the embodiment of the present invention, electrodes or electrode materials of the same polarity are arranged in opposing positions, but this is not limited to this. Electrodes or electrode materials of different polarities may be arranged in opposing positions.

In the above embodiment, a gap or step is formed or configured between the negative electrode or negative electrode material 231 and the positive electrode or positive electrode material 221, and the electrolyte 222 is filled therein, but this is not limited to the above. An insulating film or insulating wall made of an insulating material (not shown) may be formed or disposed between the negative electrode material 231 and the positive electrode material 221.

The negative electrode material 231 and the positive electrode material 221 may be patterned and separated by an etching method or the like, or the negative electrode material 231 and the positive electrode material 221 may be formed separately by a printing method. The negative electrode material 231 and the positive electrode material 221 may be formed as one electrode, and a laser or the like may be irradiated between the negative electrode material 231 and the positive electrode material 221 to separate the negative electrode material 231 and the positive electrode material 221.

In the above embodiment, a gap or step is formed or configured between the negative electrode or negative electrode material 231 and the positive electrode or positive electrode material 221, and the electrolyte 222 is filled in, but this is not limited to the above.

Figure 23 is a diagram of the structure and an explanatory diagram of a battery in another embodiment of the present invention. In Figure 23, an insulating film or insulating wall made of insulating material 312 is formed or placed between the negative electrode material 231 and the positive electrode material 221. By forming or placing insulating material 312, there is no electrolyte in the negative electrode material 231 and the positive electrode material 221, and the electric field strength between the negative electrode material 231 and the positive electrode material 221 becomes uniform.

The presence of separator 204 only prevents the positive and negative electrodes from shorting out. If the function of preventing shorting was available, separator 204 would not be necessary. However, if the structure is such that the internal resistance is governed by the conductivity of the electrolyte, it is better for the distance between the positive and negative electrodes to be short.

As shown in Fig. 23, by disposing the insulating material 312, the effective distance between the positive and negative electrodes can be shortened. If a short circuit occurs (if the resistance becomes abnormally small), the part is automatically removed, and the entire battery will function without any problems.
Examples of the insulating material 312 include inorganic materials such as SiO ₂ , SiN _x , TiO ₂ , and SiON, and organic materials such as polyethylene, polyester, and polypropylene.

The insulating material 312 may be a wall-shaped insulating wall. It goes without saying that it may also be an isolation film or isolation wall that provides isolation or isolation spacing so that the electric field strength between adjacent electrodes is uniform or there is no electric field concentration.

The negative electrode material 231 and the positive electrode material 221 may be patterned and separated by an etching method or the like, or may be formed separately by a printing method. The negative electrode material 231 and the positive electrode material 221 may be formed as one electrode, and a laser or the like may be irradiated between the negative electrode material 231 and the positive electrode material 221 to separate the negative electrode material 231 and the positive electrode material 221. It goes without saying that the configuration and form of the insulating material 312 etc. in FIG. 23 can be applied to other embodiments of the present invention.

The capacitor battery of the present invention not only functions as a capacitor, but also as a secondary battery or has secondary battery-like functions. When a voltage is applied, charging begins as the voltage rises. Initially, it is all due to the electric double layer capacitor. When a certain voltage (electromotive force) is exceeded, an oxidation-reduction reaction similar to that of a lithium-ion battery occurs. In other words, it is a new concept of an electricity storage device that combines an oxidation-reduction reaction with an electric double layer capacitor. Therefore, it has both the functions, configuration, and structure of high-speed charging and discharging and the voltage generation of a secondary battery.

The electric double-layer capacitor battery of the present invention is capable of faster charging and discharging than conventional secondary batteries. Electric double-layer capacitor batteries have excellent high-output characteristics and are expected to be applied in a variety of fields, including the storage of new energy sources.

Aqueous electric double layer capacitor batteries (secondary batteries) that use aqueous electrolytes have high electrical conductivity, excellent electrolyte dissociation and ion mobility, and are highly safe because the solvent is water, are non-volatile, easy to manage moisture, and are low cost. They also have high-speed charge and discharge capabilities.
The electric double layer capacitor battery (secondary battery) of the present invention can overcome the limitations of water electrolysis and is expected to be used in a variety of fields.

101 Charger 102 Load 107 Container 108 Insulating film 202 Positive electrode terminal 203 Negative electrode terminal 204 Separator 205 Positive electrode 206 Negative electrode 207 Gasket 222 Electrolyte 221 Positive electrode material 231 Negative electrode material 301 Substrate (film, sheet)
302 Positive electrode coating material 303 Negative electrode coating material 304 Electrode terminal 305 Inlet/outlet hole 306 Film 307 Convex portion 308 Concave portion 309 Vapor deposition material 310 Metal mask 312 Insulating material (insulating wall, partition wall)

Claims (7)

A container;
a negative electrode containing at least one of graphite, activated carbon, and acetylene black disposed in the container;
a positive electrode containing at least one of a low-spin iron complex and lithium cobalt oxide (LiCoO ₂ ) disposed in the container;
A battery comprising an aqueous solution of lithium perchlorate in a saturated state of 95% or more filled between the positive electrode and the negative electrode. A container;
a negative electrode containing at least one of graphite, activated carbon, and acetylene black disposed in the container;
a positive electrode containing lithium cobalt oxide ( _LiCoO2 ) disposed within the container;
A battery comprising an aqueous solution of lithium perchlorate in a saturated state of 95% or more filled between the positive electrode and the negative electrode. The battery according to claim 1 or 2, characterized in that the material of the positive electrode is a mixture of graphite and lithium cobalt oxide (LiCoO ₂ ), and the content ratio of the graphite to the lithium cobalt oxide (LiCoO ₂ ) is in the range of 1:0.8 to 1:1.5. 2. The battery according to claim 1, wherein the low-spin iron complex is any one of iron(II) porphyrin, [Fe(phen) ₃ ] ²⁺ , [Fe(bipy) ₃ ] ²⁺ , and [Fe(terpy) ₃ ] ²⁺ . 3. The battery according to claim 1, wherein the surface of at least one of the positive electrode and the negative _electrode is coated with _Fe2O3 . 3. The battery according to claim 1, wherein the negative electrode and the positive electrode are formed or disposed adjacent to each other on the same substrate, sheet or film. The negative electrode includes a first negative electrode and a second negative electrode,
The positive electrode includes a first positive electrode and a second positive electrode,
the first negative electrode and the first positive electrode are formed or disposed on a first substrate or a first sheet or a first film;
the second negative electrode and the second positive electrode are formed or disposed on a second substrate or a second sheet or a second film;
The first substrate, the first sheet, or the first film and the second substrate, the second sheet, or the second film are disposed facing each other;
The first negative electrode and the second negative electrode are disposed in opposing positions,
3. The battery according to claim 1, wherein the second positive electrode and the second positive electrode are disposed in opposing positions.

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