Electrode for tertiary battery, tertiary battery, method for manufacturing electrode for tertiary battery

Abstract

To provide an electrode for a three-dimentional battery, which can be manufactured in a manufacturing processing that is similar to a secondary battery, a three-dimentional battery, and a manufacturing method of the electrode for the three-dimentional battery.SOLUTION: A manufacturing method for a three-dimentional battery, includes: an electrode board 2; and a first electrode mixture layer 3 that is existed onto the electrode board 2. In an electrode of the three-dimentional battery, the first electrode mixture layer 3 contains a first electrode material, and the first electrode material contains a prussian blue analog in a partial oxidation state. The manufacturing method for the three-dimentional battery, includes: a first step of making the prussian blue analog in a completion reduction state partially oxidize to obtain the prussian blue analog in the partial oxidation state; and a second step of forming a coating film by coating an electrode component containing the prussian blue analog in the partial oxidation state onto the electrode board, drying the coating film, and forming an electrode mixture layer containing the prussian blue analog in the partial oxidation state onto the electrode board.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electrode for a tertiary battery, a tertiary battery, and a method for manufacturing an electrode for a tertiary battery. [Background technology]

[0002] Tertiary batteries are a type of energy harvesting technology that converts temperature differences in the environment into electrical energy. The performance (electromotive force and discharge capacity) of a tertiary battery is determined by the temperature coefficient (α) and capacity coefficient (β) of the oxidation-reduction potential of the electrode materials. Specifically, the electromotive force generated in a tertiary battery is expressed as ΔT × (α (positive electrode) - α (negative electrode)). Here, ΔT is the change in device temperature, α (positive electrode) is the temperature coefficient of the positive electrode material, and α (negative electrode) is the temperature coefficient of the negative electrode material (see, for example, Patent Document 1). β (positive electrode) is the capacity coefficient of the positive electrode material and depends greatly on the degree of partial oxidation of the positive electrode. β (negative electrode) is the capacity coefficient of the negative electrode material and depends greatly on the degree of partial oxidation of the negative electrode. The smaller β (positive electrode) and β (negative electrode) are, the larger the discharge capacity. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2018-73596 [Overview of the project] [Problems that the invention aims to solve]

[0004] Conventionally, the manufacturing method of tertiary batteries includes a partial oxidation process as an essential step to equalize the potentials of the positive and negative electrodes and to maximize the discharge capacity. The partial oxidation process is typically a process in which the electrodes are partially oxidized after the battery cell (half-cell) equipped with electrodes has been manufactured.

[0005] Since the conventional method for manufacturing a tertiary battery has a partial oxidation process, the manufacturing process has one more step than that of a secondary battery. Since the Prussian blue analog that constitutes the tertiary battery undergoes partial oxidation in an aqueous electrolyte, the metal electrode is corroded by the aqueous electrolyte. Therefore, an expensive ITO electrode is used.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide an electrode for a tertiary battery, a tertiary battery, and a method for manufacturing an electrode for a tertiary battery that can be manufactured by the same manufacturing process as a secondary battery.

Means for Solving the Problems

[0007] [1] An electrode for a tertiary battery, comprising an electrode plate and a first electrode binder layer present on the electrode plate, The first electrode binder layer contains a first electrode material, The first electrode material contains a Prussian blue analog in a partially oxidized state, The Prussian blue analog in the partially oxidized state is represented by the following general formula (1), and Fe or M is greater than divalent In an oxidized state , an electrode for a tertiary battery. Na x M[Fe(CN)6] y (M = Mn, Fe, Co, Ni, Cu, Cd ;0≦x<4y-2, 0.67 <y<1.00 ) (1) [2] A first electrode and a second electrode face each other through a single electrolyte, The first electrode is the electrode for a tertiary battery according to claim 1, The second electrode includes an electrode plate and a second electrode binder layer present on the electrode plate, The second electrode binder layer contains a second electrode material, The second electrode material contains a Prussian blue analog in a partially oxidized state or a Prussian blue analog in a completely reduced state, The Prussian blue analog in the partially oxidized state is represented by the following general formula (1), and Fe or M is greater than divalent It is in an oxidized state. , The Prussian blue analog in the completely reduced state is represented by the following general formula (2) Fe and M are in a divalent state., a tertiary battery. Na x M[Fe(CN)6] y (M = Mn, Fe, Co, Ni, Cu, Cd ;0≦x<4y-2, 0.67 <y<1.00 ) (1) Na 4y-2 M[Fe(CN)6] y (M = Mn, Fe, Co, Ni, Cu, Cd; 0.67 < y < 1.00) (2) [3] A first step of partially oxidizing a Prussian blue analog in a fully reduced state to obtain a Prussian blue analog in a partially oxidized state, A second step of applying an electrode composition containing the Prussian blue analog in the partially oxidized state onto an electrode plate to form a coating film, drying the coating film, and forming an electrode active material layer containing the Prussian blue analog in the partially oxidized state on the electrode plate. The Prussian blue analog in the partially oxidized state is represented by the following general formula (1), and Fe or M is greater than divalent It is in an oxidized state. , The Prussian blue analog in the fully reduced state is represented by the following general formula (2) Fe and M are in a divalent state. , a method for manufacturing an electrode for a tertiary battery. Na x M[Fe(CN) 6 ] y (M = Mn, Fe, Co, Ni, Cu, Cd ;0≦x<4y-2, 0.67 < y < 1.00) (1) Na 4y-2 M[Fe(CN)6] y (M = Mn, Fe, Co, Ni, Cu, Cd; 0.67 < y < 1.00) (2) [4] The first step is a step of mixing a first solution containing sodium chloride and one selected from a chloride of a transition metal, a bromide of a transition metal, and a nitrate of a transition metal, and a second solution containing sodium chloride, sodium ferrocyanide, and potassium ferricyanide or sodium ferricyanide, filtering and recovering the precipitate to obtain the Prussian blue analog in the partially oxidized state. The method for manufacturing an electrode for a tertiary battery according to [3]. [5] The method for manufacturing an electrode for a tertiary battery according to [3], wherein the first step is to mix a fully reduced Prussian blue analog with an oxidizing agent to obtain the partially oxidized Prussian blue analog. [6] A method for manufacturing an electrode for a tertiary battery according to [3], comprising mixing a fully reduced Prussian blue analog with a fully oxidized Prussian blue analog, forming an electrode mixture layer containing the mixture on an electrode plate to form an electrode, and immersing the electrode in an electrolyte to convert the fully reduced Prussian blue analog and the fully oxidized Prussian blue analog contained in the electrode mixture layer into a partially oxidized Prussian blue analog. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an electrode for a tertiary battery, a tertiary battery, and a method for manufacturing an electrode for a tertiary battery, which can be manufactured using the same manufacturing process as for a secondary battery. [Brief explanation of the drawing]

[0009] [Figure 1] This is a cross-sectional view showing an electrode for a tertiary battery according to one embodiment of the present invention. [Figure 2] This is a cross-sectional view showing a tertiary battery according to one embodiment of the present invention. [Figure 3] This figure shows the X-ray diffraction patterns of the powder obtained in Experimental Example 1 and the Na1.76Ni[Fe(CN)6]0.94 powder. [Figure 4] This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 1. [Figure 5] This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 2. [Figure 6] This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 3. [Figure 7] This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 4. [Figure 8] This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 5. [Figure 9]This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 6. [Figure 10] This figure shows the results of measuring the electromotive force of the electrode containing the powder obtained in Experimental Example 7. [Modes for carrying out the invention]

[0010] Embodiments of the electrode for a tertiary battery, the tertiary battery, and the method for manufacturing the electrode for a tertiary battery according to the present invention will be described. This embodiment is provided to give a better understanding of the spirit of the invention and does not limit the present invention unless otherwise specified.

[0011] [Electrode for tertiary battery] The following describes an electrode for a tertiary battery according to one embodiment of the present invention, with reference to the drawings. Figure 1 is a cross-sectional view showing an electrode for a tertiary battery according to one embodiment of the present invention. As shown in Figure 1, the electrode 1 for the tertiary battery of this embodiment has an electrode plate 2 and an electrode mixture layer (first electrode mixture layer) 3 present on the electrode plate 2.

[0012] The electrode mixture layer 3 contains an electrode material (first electrode material). The electrode material contains a Prussian blue analog in a partially oxidized state.

[0013] The electrode plate 2 is not particularly limited, but examples include metal electrodes. Examples of metal electrodes include electrodes made of copper, aluminum, and the like.

[0014] A partially oxidized Prussian blue analog is represented by the following general formula (1), where Fe or M is greater than the 2 valent value in general formula (1). Na x M[Fe(CN)6] y (M=Mn, Fe, Co, Ni, Cu, Cd) (1)

[0015] In addition, the Prussian blue analog in the fully reduced state is represented by the following general formula (2). Na 4y-2 M[Fe(CN)6] y (M = Mn, Fe, Co, Ni, Cu, Cd; 0.67 < y < 1.00) (2)

[0016] Also, the Prussian blue analog in the fully oxidized state is represented by the following general formula (3), the following general formula (4), the following general formula (5), or the following general formula (6). Na 3y-2 M[Fe(CN)6] y (M = Ni, Cu, Cd; 0.67 < y < 0.80; Fe is trivalent, M is divalent) (3) M[Fe(CN)6] y (M = Fe, Mn; 0.67 < y < 1.00) (4) M[Fe(CN)6] y (M = Co; 0.80 < y < 1.00) (5) Na 3y-2 M[Fe(CN)6] y (M = Co; 0.67 < y < 0.80; Fe is trivalent, M is divalent) (6)

[0017] In addition to the Prussian blue analog in the partially oxidized state, the electrode binder layer 3 may contain a binder resin (binder) and a conductive aid. Examples of the binder resin include polyvinylidene fluoride (PVdF) resin, polytetrafluoroethylene (PTFE) resin, fluorine rubber, and the like. Examples of the conductive aid include Ketjen black, acetylene black (AB), furnace black, vapor-grown carbon fiber (VGCF), carbon nanotube, and the like.

[0018] According to the electrode 1 for a tertiary battery of the present embodiment, since the electrode material contained in the electrode binder layer 3 contains a Prussian blue analog in the partially oxidized state, the partial oxidation process that was conventionally required in the manufacture of tertiary batteries becomes unnecessary, and it can be manufactured by the same manufacturing process as that of secondary batteries.

[0019] [Manufacturing Method of Electrode for Tertiary Battery] A method for manufacturing an electrode for a tertiary battery according to one embodiment of the present invention comprises: a first step of partially oxidizing a fully reduced Prussian blue analog to obtain a partially oxidized Prussian blue analog; and a second step of applying an electrode composition containing the partially oxidized Prussian blue analog onto an electrode plate to form a coating film, and drying the coating film to form an electrode mixture layer containing the partially oxidized Prussian blue analog on the electrode plate. The Prussian blue analog in the partially oxidized state is represented by the above general formula (1), in which Fe or M is greater than the divalent value in the above general formula (1). The Prussian blue analog in the fully reduced state is represented by the above general formula (2).

[0020] "First Embodiment" (First step) The method for manufacturing an electrode for a tertiary battery according to the first embodiment is a first step in which a first solution containing sodium chloride and one selected from a transition metal chloride, a transition metal bromide, and a transition metal nitrate is mixed with a second solution containing sodium chloride, sodium ferrocyanide, and potassium ferricyanide or sodium ferricyanide, and the precipitate is filtered and recovered to obtain the partially oxidized Prussian blue analog.

[0021] The first solution comprises sodium chloride and one selected from transition metal chlorides, transition metal bromides, and transition metal nitrates. The concentration of sodium chloride in the first solution is not particularly limited, but is preferably, for example, 1 mol / L to 5 mol / L. The concentration of one of the transition metals selected from the transition metal chloride, transition metal bromide, and transition metal nitrate in the first solution is not particularly limited, but is preferably, for example, 5 mmol / L to 30 mmol / L.

[0022] The second solution contains sodium chloride, sodium ferrocyanide (Na4[Fe(CN)6]), and potassium ferricyanide (K3[Fe(CN)6]) or sodium ferricyanide (Na3[Fe(CN)6]). The concentration of sodium chloride in the second solution is not particularly limited, but for example, 1 mol / L to 5 mol / L is preferable. The concentration of sodium ferrocyanide in the second solution is not particularly limited, but for example, 5 mmol / L to 30 mmol / L is preferable. The concentration of potassium ferricyanide or sodium ferricyanide in the second solution is not particularly limited, but for example, 5 mmol / L to 30 mmol / L is preferable. The mixing ratio of sodium ferrocyanide and potassium ferricyanide or sodium ferricyanide in the second solution is not particularly limited and is appropriately adjusted according to the degree of partial oxidation of sodium ferrocyanide. When using potassium ferricyanide as a raw material, it is necessary to replace potassium ions in the second solution with sodium ions. To replace potassium ions with sodium ions, for example, Na 3y-2 Ni[Fe(CN)6] y (0.67 < y < 1.00) fine powder is added and stirred well.

[0023] When the first solution and the second solution are mixed, a partially oxidized Prussian blue analog is obtained as a precipitate. The precipitate is collected by filtration with filter paper, washed thoroughly, and dried. The temperature when the first solution and the second solution are mixed is not particularly limited, but for example, it is room temperature (25°C) to 50°C. After the first solution and the second solution are mixed, the time for holding the mixed solution is not particularly limited, but for example, it is 1 hour to 5 hours.

[0024] (The second step) In the first step, a partially oxidized Prussian blue analog is mixed with a binder resin (binding agent) and a conductive additive to form an electrode composition, which is then applied to an electrode plate to form a coating film. Next, the coating film is dried to form an electrode mixture layer containing a partially oxidized Prussian blue analog on the electrode plate.

[0025] "Second Embodiment" (First step) The method for manufacturing electrodes for tertiary batteries according to the second embodiment is a first step of mixing a fully reduced Prussian blue analog with an oxidizing agent to obtain a partially oxidized Prussian blue analog.

[0026] The Prussian blue analog in its fully reduced state is represented by the general formula (2) above.

[0027] The oxidizing agent is not particularly limited as long as it can oxidize a Prussian blue analog in a fully reduced state, but examples include potassium permanganate (KMnO4).

[0028] The mixing ratio of the fully reduced Prussian blue analog to the oxidizing agent is not particularly limited and can be adjusted as appropriate depending on the degree to which the fully reduced Prussian blue analog is partially oxidized.

[0029] To mix a fully reduced Prussian blue analog with an oxidizing agent, the fully reduced Prussian blue analog is dispersed in distilled water. When dispersing the fully reduced Prussian blue analog in distilled water, the concentration of the oxidizing agent is not particularly limited, but for example, when using potassium permanganate as the oxidizing agent, the concentration should be greater than 0 moles and less than or equal to 1 / 3 moles of the fully reduced Prussian blue analog.

[0030] A distilled water (dispersion) containing a fully reduced Prussian blue analog and an oxidizing agent is held, for example, at room temperature (25°C) to 50°C for 1 to 5 hours.

[0031] The above dispersion is held at a predetermined temperature for a predetermined time, and then filtered to obtain a Prussian blue analog in a partially oxidized state.

[0032] (Second step) The second step is carried out in the same manner as in the first embodiment.

[0033] "Third Embodiment" The third embodiment of the method for manufacturing an electrode for a tertiary battery involves mixing a fully reduced Prussian blue analog with a fully oxidized Prussian blue analog, forming an electrode mixture layer containing the mixture on an electrode plate to form an electrode, and immersing the electrode in an electrolyte to convert the fully reduced Prussian blue analog and the fully oxidized Prussian blue analog contained in the electrode mixture layer into a partially oxidized Prussian blue analog. The third embodiment of the method for manufacturing electrodes for tertiary batteries is a method for manufacturing electrodes for tertiary batteries through a process that includes the first and second steps described above.

[0034] The Prussian blue analog in its fully reduced state is represented by the general formula (2) above.

[0035] Prussian blue analogs in their fully oxidized state are represented by the above general formulas (3), (4), (5), or (6).

[0036] The mixing ratio of the fully reduced Prussian blue analog to the fully oxidized Prussian blue analog is not particularly limited and can be adjusted as appropriate depending on the degree to which the fully reduced Prussian blue analog is partially oxidized.

[0037] In the third embodiment of the method for manufacturing electrodes for tertiary batteries, a fully reduced Prussian blue analog and a fully oxidized Prussian blue analog are mixed, and the mixture is mixed with a binder resin (binding agent) and a conductive additive to form an electrode composition, which is then applied to an electrode plate to form a coating film. Next, the coating film is dried to form an electrode mixture layer containing a partially oxidized Prussian blue analog on the electrode plate. By immersing the electrodes obtained in this way in an electrolyte, electrons and sodium are exchanged between the fully reduced Prussian blue analog and the fully oxidized Prussian blue analog within the electrodes, which enhances electrical contact. This converts the fully reduced and fully oxidized Prussian blue analogs into a partially oxidized Prussian blue analog.

[0038] According to the method for manufacturing electrodes for tertiary batteries of this embodiment, since the electrode composition for forming the electrode mixture layer contains a partially oxidized Prussian blue analog, the partial oxidation step that was conventionally required in the manufacture of tertiary batteries is eliminated, and they can be manufactured using the same manufacturing process as secondary batteries.

[0039] [Tertiary battery] Figure 2 is a cross-sectional view showing a tertiary battery according to one embodiment of the present invention. In Figure 2, the same reference numerals are used for components identical to those in Figure 1, and their descriptions are omitted. As shown in Figure 2, the tertiary battery 10 of this embodiment has a first electrode 11, a second electrode 12, and an electrolyte 13.

[0040] The first electrode 11 is the electrode 1 for the tertiary battery in the embodiment described above.

[0041] The second electrode 12 comprises an electrode plate 14 and an electrode mixture layer (second electrode mixture layer) 15 present on the electrode plate 14.

[0042] The electrode mixture layer 15 contains an electrode material (second electrode material). The electrode material includes a Prussian blue analog in a partially oxidized state or a Prussian blue analog in a fully reduced state. Furthermore, if the electrode mixture layer 15 of the second electrode 12 contains a fully reduced Prussian blue analog, after fabricating the tertiary battery 10, the first electrode 11 and the second electrode 12 are short-circuited via a resistor to partially oxidize the fully reduced Prussian blue analog contained in the electrode mixture layer 15. This allows the tertiary battery 10 to function.

[0043] The electrode plate 14 is the same as the electrode plate 2.

[0044] Examples of Prussian blue analogs in the fully reduced state include those represented by the general formula (2) above.

[0045] The second electrode material described above may contain, in addition to a partially oxidized or fully reduced Prussian blue analog, a binder resin (binding agent) or a conductive additive.

[0046] According to the tertiary battery 10 of this embodiment, it is possible to convert thermal energy into electrical energy by utilizing the temperature change of the entire element, and it is also possible to make it thinner. [Examples]

[0047] The present invention will be described in more detail below with reference to experimental examples, but the present invention is not limited to the following experimental examples.

[0048] [Experimental Example 1] Na 1.76 Ni[Fe(CN)6] 0.94 The powder was partially oxidized with potassium permanganese. Na 1.76 Ni[Fe(CN)6] 0.94 Disperse 120 mg of powder in 10 ml of distilled water, Na 1.76 Ni[Fe(CN)6] 0.94 A dispersion of the powder was prepared. The resulting dispersion was kept at 50°C for 1 hour. In the above dispersion, Na 1.76 Ni[Fe(CN)6] 0.94 Add potassium permanganate in amounts of 1 / 3, 1 / 6, or 1 / 12 of the moles of Ni, and stir for 1 hour. The dispersion containing potassium permanganate was then filtered, washed with distilled water, and the powder was collected using filter paper.

[0049] "X-ray diffraction" The powder obtained in Experimental Example 1 (partially oxidized powder) and Na 1.76Ni[Fe(CN)6] 0.94 X-ray diffraction (XRD) was performed on the powder. A Rigaku MiniFlex (product name) X-ray diffractometer was used. The results of the X-ray diffraction are shown in Figure 3. From the results shown in Figure 3, Na 1.76 Ni[Fe(CN)6] 0.94 Add potassium permanganate to Na 1.76 Ni[Fe(CN)6] 0.94 Even if Na is partially oxidized, 1.76 Ni[Fe(CN)6] 0.94 It was confirmed that the framework (crystal structure) was preserved.

[0050] "Measurement of electromotive force of electrodes containing powder" On the ITO electrode plate, Na 1.76 Ni[Fe(CN)6] 0.94 An electrode composition containing a powder obtained by adding potassium permanganate in an amount equal to 1 / 3 the number of moles of Ni, polyvinylidene fluoride resin, and acetylene black was applied to form a coating film, and the coating film was dried to form an electrode mixture layer containing the electrode material on the electrode plate, thereby obtaining an electrode. Using an Ag / AgCl standard electrode as the counter electrode, the electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes. As the electrolyte, an aqueous solution containing 17 mol / kg of sodium perchlorate (NaClO4) was used. The measurement temperature was set to 50°C. The results are shown in Figure 4. From the results shown in Figure 4, the ratio of the second charge capacity (blue line) to the first charge capacity (red line) is Na 1.76 Ni[Fe(CN)6] 0.94 The degree of oxidation of Na changed from 0.25. 1.76 Ni[Fe(CN)6] 0.94 It was confirmed that it is partially oxidized with potassium permanganate.

[0051] [Experimental Example 2] Solution A1 was prepared containing 4 mol / L of sodium chloride and 10 mmol / L of cobalt chloride. Distilled water was used as the solvent. Solution B1 was prepared containing 4 mol / L of sodium chloride and 10 mmol / L of Na4[Fe(CN)6]. Distilled water was used as the solvent. 100 mL of solution A1 and 100 mL of solution B1 were mixed at 35°C, the mixture was held for 12 hours, washed with distilled water, filtered, and a powder was obtained.

[0052] "Measurement of heavy metal element ratios" The heavy metal element ratio of the powder obtained in Experimental Example 2 was quantified using an energy-dispersive X-ray spectrometer (SEM-EDX). A JST-IT2000 (product name) manufactured by JEOL Ltd. was used as the energy-dispersive X-ray spectrometer. The results are shown in Table 1.

[0053] "Measurement of electromotive force of electrodes containing powder" On the ITO electrode plate, the powder (Na) obtained in Experimental Example 2 was placed. 1.49 Co[Fe(CN)6] 0.88 An electrode composition containing polyvinylidene fluoride resin and acetylene black was applied to form a coating film, and the coating film was dried to form an electrode mixture layer containing electrode material on the electrode plate to obtain an electrode. Using an Ag / AgCl standard electrode as the counter electrode, the electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes. As the electrolyte, an aqueous solution containing 17 mol / kg of sodium perchlorate (NaClO4) was used. The measurement temperature was set to 50°C. The results are shown in Figure 5. As shown in Figure 5, the ratio of the second charge capacity to the first charge capacity changed the degree of oxidation of Na4[Fe(CN)6] from 0.02.

[0054] [Experimental Example 3] Solution A1 was prepared containing 4 mol / L of sodium chloride and 10 mmol / L of cobalt chloride. Distilled water was used as the solvent. Solution B2 was prepared containing 4 mol / L sodium chloride, 4 mmol / L Na4[Fe(CN)6], and 6 mmol / L K3[Fe(CN)6]. Distilled water was used as the solvent. 100 mL of solution A1 and 100 mL of solution B2 were mixed at 35°C, the mixture was held for 12 hours, washed with distilled water, filtered, and a powder was obtained.

[0055] "Measurement of heavy metal element ratios" The heavy metal element ratio of the powder obtained in Experimental Example 3 was quantified in the same manner as in Experimental Example 2. The results are shown in Table 1.

[0056] "Measurement of electromotive force of electrodes containing powder" The powder obtained in Experimental Example 3 (Na 1.23 Co[Fe(CN)6] 0.82 The electrodes were obtained in the same manner as in Experimental Example 2, except that a different material was used. The electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes, in the same manner as in Experimental Example 2. The results are shown in Figure 6. As shown in Figure 6, the ratio of the second charge capacity to the first charge capacity indicates that the degree of oxidation of Na4[Fe(CN)6] was 0.04.

[0057] [Experimental Example 4] Solution A1 was prepared containing 4 mol / L of sodium chloride and 10 mmol / L of cobalt chloride. Distilled water was used as the solvent. Solution B3 was prepared containing 4 mol / L sodium chloride, 2 mmol / L Na4[Fe(CN)6], and 8 mmol / L K3[Fe(CN)6]. Distilled water was used as the solvent. 100 mL of solution A1 and 100 mL of solution B3 were mixed at 35°C, the mixture was held for 12 hours, washed with distilled water, filtered, and a powder was obtained.

[0058] "Measurement of heavy metal element ratios" The heavy metal element ratio of the powder obtained in Experimental Example 4 was quantified in the same manner as in Experimental Example 2. The results are shown in Table 1.

[0059] "Measurement of electromotive force of electrodes containing powder" The powder obtained in Experimental Example 4 (Na 1.32 Co[Fe(CN)6] 0.85The electrodes were obtained in the same manner as in Experimental Example 2, except that a different material was used. The electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes, in the same manner as in Experimental Example 2. The results are shown in Figure 7. As shown in Figure 7, the ratio of the second charge capacity to the first charge capacity changed the degree of oxidation of Na4[Fe(CN)6] from 0.07.

[0060] [Table 1]

[0061] [Experimental Example 5] Solution A2 was prepared, containing 4 mol / L of sodium chloride and 10 mmol / L of nickel chloride. Distilled water was used as the solvent. Solution B1 was prepared containing 4 mol / L of sodium chloride and 10 mmol / L of Na4[Fe(CN)6]. Distilled water was used as the solvent. 100 mL of solution A2 and 100 mL of solution B1 were mixed at 35°C, the mixture was held for 12 hours, washed with distilled water, filtered, and a powder was obtained.

[0062] "Measurement of heavy metal element ratios" The heavy metal element ratio of the powder obtained in Experimental Example 5 was quantified in the same manner as in Experimental Example 2. The results are shown in Table 2.

[0063] "Measurement of electromotive force of electrodes containing powder" The powder obtained in Experimental Example 5 (Na 1.25 Ni[Fe(CN)6] 0.82 The electrodes were obtained in the same manner as in Experimental Example 2, except that a different material was used. The electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes, in the same manner as in Experimental Example 2. The results are shown in Figure 8. As shown in Figure 8, the ratio of the second charge capacity to the first charge capacity changed the degree of oxidation of Na4[Fe(CN)6] from 0.02.

[0064] [Experimental Example 6] Solution A2 was prepared, containing 4 mol / L of sodium chloride and 10 mmol / L of nickel chloride. Distilled water was used as the solvent. Solution B4 was prepared containing 4 mol / L sodium chloride, 5 mmol / L Na4[Fe(CN)6], and 5 mmol / L K3[Fe(CN)6]. Distilled water was used as the solvent. 100 mL of solution A2 and 100 mL of solution B4 were mixed at 35°C, the mixture was held for 12 hours, washed with distilled water, filtered, and a powder was obtained.

[0065] "Measurement of heavy metal element ratios" The heavy metal element ratios of the powders obtained in Experimental Example 6 were quantified in the same manner as in Experimental Example 2. The results are shown in Table 2.

[0066] "Measurement of electromotive force of electrodes containing powder" The powder obtained in Experimental Example 6 (Na 1.25 Ni[Fe(CN)6] 0.85 The electrodes were obtained in the same manner as in Experimental Example 2, except that a different material was used. The electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes, in the same manner as in Experimental Example 2. The results are shown in Figure 9. As shown in Figure 9, the ratio of the second charge capacity to the first charge capacity changed the degree of oxidation of Na4[Fe(CN)6] from 0.11.

[0067] [Experimental Example 7] Solution A2 was prepared, containing 4 mol / L of sodium chloride and 10 mmol / L of nickel chloride. Distilled water was used as the solvent. Solution B5 was prepared containing 4 mol / L sodium chloride, 1 mmol / L Na4[Fe(CN)6], and 9 mmol / L K3[Fe(CN)6]. Distilled water was used as the solvent. 100 mL of solution A2 and 100 mL of solution B5 were mixed at 35°C, the mixture was held for 12 hours, washed with distilled water, filtered, and a powder was obtained.

[0068] "Measurement of heavy metal element ratios" The heavy metal element ratio of the powder obtained in Experimental Example 7 was quantified in the same manner as in Experimental Example 2. The results are shown in Table 2.

[0069] "Measurement of electromotive force of electrodes containing powder" The powder obtained in Experimental Example 7 (Na 1.18 Ni[Fe(CN)6] 0.85 The electrodes were obtained in the same manner as in Experimental Example 2, except that a different material was used. The electromotive force of the electrode mixture layer of the above electrode was measured in response to temperature changes, in the same manner as in Experimental Example 2. The results are shown in Figure 10. As shown in Figure 10, the ratio of the second charge capacity to the first charge capacity changed the degree of oxidation of Na4[Fe(CN)6] from 0.16.

[0070] [Table 2] [Explanation of Symbols]

[0071] 1 Electrode for tertiary battery 2 Electrode plate 3. Electrode mixture layer (first electrode mixture layer) 10 Tertiary battery 11 First electrode 12 Second electrode 13 Electrolyte 14 Electrode plate 15 Electrode mixture layer (second electrode mixture layer)

Claims

1. It comprises an electrode plate and a first electrode mixture layer present on the electrode plate, The first electrode mixture layer comprises the first electrode material, The first electrode material comprises a Prussian blue analog in a partially oxidized state. The Prussian blue analog in the partially oxidized state is represented by the following general formula (1), and is an electrode for a tertiary battery in which Fe or M is in an oxidation state greater than divalent. Na ｘ M[Fe(CN) ６ ] ｙ (M=M.、Fe、Co、Ni、Cu、Cd;0≦x<4y-2、0.67<y<1.00) (1)

2. The first electrode and the second electrode are positioned opposite each other with a single electrolyte in between. The first electrode is the electrode for a tertiary battery described in claim 1, The second electrode comprises an electrode plate and a second electrode mixture layer present on the electrode plate. The second electrode mixture layer comprises the second electrode material, The second electrode material comprises a Prussian blue analog in a partially oxidized state or a Prussian blue analog in a fully reduced state. The Prussian blue analog in the partially oxidized state is represented by the following general formula (1), where Fe or M is in an oxidation state greater than divalent. The Prussian blue analog in the fully reduced state is represented by the following general formula (2), and the tertiary battery is in which Fe and M are in a divalent state. Na ｘ M[Fe(CN) ６ ] ｙ (M=M.、Fe、Co、Ni、Cu、Cd;0≦x<4y-2、0.67<y<1.00) (1) Na ４ｙ－２ M[Fe(CN) ６ ] ｙ (M=Mn、Fe、Co、Ni、Cu、Cd;0.67<y<1.00) (2)

3. The first step involves partially oxidizing a fully reduced Prussian blue analog to obtain a partially oxidized Prussian blue analog, The method comprises a second step of applying an electrode composition containing the partially oxidized Prussian blue analog onto an electrode plate to form a coating film, and drying the coating film to form an electrode mixture layer containing the partially oxidized Prussian blue analog on the electrode plate. The Prussian blue analog in the partially oxidized state is represented by the following general formula (1), where Fe or M is in an oxidation state greater than divalent. A method for manufacturing electrodes for tertiary batteries, wherein the fully reduced Prussian blue analog is represented by the following general formula (2), and Fe and M are in a divalent state. Na x M[Fe(CN) 6 ] y (M=Mn, Fe, Co, Ni, Cu, Cd; 0≦x<4y-2, 0.67<y<1.00) (1) Na ４ｙ－２ M[Fe(CN) ６ ] ｙ (M=Mn、Fe、Co、Ni、Cu、Cd;0.67<y<1.00) (2)

4. The method for producing an electrode for a tertiary battery according to claim 3, wherein the first step is to mix a first solution containing sodium chloride and one selected from a transition metal chloride, a transition metal bromide, and a transition metal nitrate with a second solution containing sodium chloride, sodium ferrocyanide, and potassium ferricyanide or sodium ferricyanide, and then filter and recover the precipitate to obtain the partially oxidized Prussian blue analog.

5. The method for manufacturing an electrode for a tertiary battery according to claim 3, wherein the first step is to mix a fully reduced Prussian blue analog with an oxidizing agent to obtain the partially oxidized Prussian blue analog.

6. A method for manufacturing an electrode for a tertiary battery according to claim 3, comprising: mixing a fully reduced Prussian blue analog with a fully oxidized Prussian blue analog; forming an electrode mixture layer containing the mixture on an electrode plate to serve as an electrode; and immersing the electrode in an electrolyte to convert the fully reduced Prussian blue analog and the fully oxidized Prussian blue analog contained in the electrode mixture layer into a partially oxidized Prussian blue analog.

Images