Electrodes for secondary batteries, secondary batteries, aircraft, and methods for producing electrodes for secondary batteries

Abstract

To provide an electrode for a secondary battery which is used as a cathode or an anode of a secondary battery.SOLUTION: An electrode for a secondary battery is provided which comprises an electrolytic solution, or a solid or gelatinous electrolyte, the electrode further comprises a current collector 222 including electrically conductive substance and an active substance layer 224 in contact with at least a part of the current collector and including an active substance. In at least either the current collector or the active substance layer of the electrode for a secondary battery, ion permeation regions 462, 464 each at least having either a gap that allows electrolyte ions of the electrolytic solution to be entered therein or an ion conducting substance having an ion transport number higher than that of the active substance are disposed. The ion permeation region may be disposed at positions where the electrolytic solution or the electrolyte of the secondary battery can come into contact with a surface of the active substance when the electrode for a secondary battery is assembled in a secondary battery.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an electrode for a secondary battery, a secondary battery, an aircraft, and a method for producing an electrode for a secondary battery. [Background Art]

[0002] Patent Document 1 discloses that by employing a positive electrode containing rubeanic acid or a rubeanic acid polymer as a positive electrode active material, an electricity storage cell having a capacity density of about 400 [Ah / kg-electricity storage cell] can be produced. Patent Document 2 discloses that by employing a positive electrode containing a disulfide-based organic compound, an electricity storage cell having high energy density, high capacity and excellent stability can be produced. However, further improvement in performance of electricity storage cells is desired. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-147015 [Patent Document 2] U.S. Patent No. 4833048 specification [Summary of the Invention]

[0003] According to a first aspect of the present invention, an electrode for a secondary battery is provided. The electrode for a secondary battery described above is used, for example, as a positive electrode or a negative electrode of a secondary battery including an electrolytic solution or a solid or gel electrolyte. The electrode for a secondary battery described above includes, for example, a current collector containing a conductive substance. The electrode for a secondary battery described above includes, for example, an active material layer that is in contact with at least a part of the current collector and contains an active material. In the electrode for a secondary battery described above, for example, an ion permeable region is disposed in at least one of the current collector and the active material layer. The ion permeable region has, for example, at least one of a void into which electrolyte ions of the electrolytic solution can penetrate, and an ion conductive material having a higher ion transference number than the active material.

[0004] In the above electrode for a secondary battery, the ion permeable region may be arranged at a position capable of contacting the electrolyte solution or electrolyte of the secondary battery and the surface of the active material when the electrode for a secondary battery is incorporated into the secondary battery. In the above electrode for a secondary battery, the active material may include a crystalline or amorphous organic compound or a salt thereof. In the above electrode for a secondary battery, the active material may be a compound having a dithiadiazine group or a salt thereof. In the above electrode for a secondary battery, the compound having a dithiadiazine group may include a compound represented by the following general formula (1) or a derivative thereof. [General Formula (1)]

Chemical Formula

[0005] In the above electrode for a secondary battery, the voids of the ion permeable region may include pores having a diameter of 1 μm or more formed on the surface of the active material layer. In the above electrode for a secondary battery, the active material layer may have a plurality of particles containing the active material and a binder. The voids of the ion permeable region may be formed between the plurality of particles, and may extend from the surface of the active material layer toward the inside of the active material layer.

[0006] In the above electrode for a secondary battery, the ion conductive material in the ion permeable region may include at least one of a polymer gel electrolyte, a polymer electrolyte, and a solid electrolyte. In the above electrode for a secondary battery, the ion conductive material in the ion permeable region may include a mixture or a reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. In the above electrode for a secondary battery, the active material layer may include the active material and a binder. The ion conductive material in the ion permeable region may include a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound.

[0007] In the above-described electrode for a secondary battery, the secondary battery may include an electrolyte. In the above-described electrode for a secondary battery, the current collector and the active material layer may be arranged so that the first surface of the current collector and the first surface of the active material layer are in contact. The void in the ion-permeable region may include at least one of (i) a recess formed on the first surface of the current collector and extending from the side surface of the current collector toward the interior of the current collector, (ii) a through hole penetrating the current collector, and (iii) a recess disposed on the first surface of the active material layer and extending from the side surface of the active material layer toward the interior of the active material layer. In the above-described electrode for a secondary battery, the current collector and the active material layer may be arranged so that the first surface of the current collector and the first surface of the active material layer are in contact. The void in the ion-permeable region may include a second surface disposed on the opposite side of the first surface of the active material layer, or a recess formed on the side surface of the active material layer. In the above-described electrode for a secondary battery, the recess may have a hole shape, a groove shape, a depression shape, or a combination thereof.

[0008] In the above-described secondary battery electrode, the volume of the ion-permeable region may be 50% or less of the volume of the active material layer, including the volume of the ion-permeable region disposed within the active material layer. In the above-described secondary battery electrode, the mass of the ion-conducting material contained in the ion-permeable region may be 50% or less of the mass of the active material layer, including the mass of the ion-permeable region disposed within the active material layer. In the above-described secondary battery electrode, the thickness of the active material layer may be 80 μm or more.

[0009] In a second aspect of the present invention, a secondary battery is provided. The secondary battery comprises, for example, an electrode for a secondary battery according to the first aspect. The secondary battery comprises, for example, an electrolyte or a solid or gel-like electrolyte.

[0010] In a third aspect of the present invention, an aircraft is provided. The aircraft comprises, for example, a secondary battery according to the second aspect. The aircraft comprises, for example, a thrust generating device that generates thrust using electrical energy stored in the secondary battery.

[0011] A fourth aspect of the present invention provides a method for producing an electrode for a secondary battery, which includes a current collector and an active material layer. The production method includes, for example, the step of preparing a slurry containing an active material, an ion-conducting material having a greater ion transport rate than the active material, and a solvent. The production method includes, for example, the step of applying the slurry to the surface of the current collector. The production method includes, for example, the step of drying the slurry so that the active material and the ion-conducting material undergo phase separation.

[0012] It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. Furthermore, subcombinations of these features may also constitute an invention. [Brief explanation of the drawing]

[0013] [Figure 1] A schematic example of the system configuration of aircraft 100 is shown below. [Figure 2] A schematic example of a storage cell 112 is shown below. [Figure 3] Another example of the energy storage cell 112 is schematically shown below. [Figure 4] A schematic example of a cross-section of the positive electrode 220 is shown. [Figure 5] A schematic example of a cross-section of the positive electrode active material layer 224 is shown. [Figure 6] Another example of a cross-section of the positive electrode active material layer 224 is schematically shown. [Figure 7] Another example of a cross-section of the positive electrode 220 is schematically shown. [Figure 8] Further schematic examples of the cross-section of the positive electrode 220 are shown below. [Figure 9] An example of a production method for positive electrode 220 is outlined below. [Modes for carrying out the invention]

[0014] In recent years, in order to improve the capacity density per unit mass of the active material, secondary batteries using organic compounds with relatively small molecular weights as active materials have been developed. To improve the capacity density per unit mass, it is conceivable to increase the thickness of the active material layer arranged in the electrodes. However, even when the thickness of the active material layer is increased, the capacity does not always improve as much as expected from the increase in the amount of active material. According to one embodiment of this technology, the movement of ions inside the electrode is improved. For example, a region in which electrolyte ions can move is formed inside the electrode. This improves the energy density, output, and / or lifespan of the secondary battery. The secondary battery according to this embodiment has a high energy density per unit mass, making it particularly suitable for applications in aircraft.

[0015] The present invention will be described below through embodiments of the invention, but these embodiments are not intended to limit the invention as defined in the claims. Furthermore, not all combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0016] In this specification, when a numerical range is expressed as "A to B", it means A or greater and B or less. Furthermore, "substituted or unsubstituted" means "substituted with any substituent, or not substituted with any substituent." The types of substituents are not particularly limited unless otherwise specified in the specification. Furthermore, the number of substituents is not particularly limited unless otherwise specified in the specification.

[0017] Figure 1 schematically shows an example of the system configuration of the aircraft 100. In this embodiment, the aircraft 100 comprises a battery 110, a power control circuit 120, one or more electric motors 130, one or more propellers 140, one or more sensors 150, and a control device 160. In this embodiment, the battery 110 has one or more energy storage cells 112.

[0018] In this embodiment, the aircraft 100 flies using electrical energy stored in the battery 110. Examples of the aircraft 100 include airplanes, airships, balloons, helicopters, and drones.

[0019] In this embodiment, the battery 110 receives electrical energy from an external charging device or power generation device (not shown) via the power control circuit 120 and stores the electrical energy in one or more energy storage cells 112. The battery 110 also supplies the electrical energy stored in one or more energy storage cells 112 to the electric motor 130 via the power control circuit 120.

[0020] In this embodiment, the energy storage cell 112 stores electrical energy (sometimes referred to as charging the energy storage cell 112). The energy storage cell 112 also releases the stored electrical energy (sometimes referred to as discharging the energy storage cell 112). The energy storage cell 112 may be a secondary battery. The energy storage cell 112 may be a non-aqueous secondary battery.

[0021] Examples of non-aqueous secondary batteries include sodium-ion secondary batteries, lithium-ion secondary batteries, lithium-metal secondary batteries, lithium-air secondary batteries, lithium-sulfur secondary batteries, magnesium-ion secondary batteries, and aluminum-ion secondary batteries. Furthermore, lithium-ion secondary batteries, which are one form of non-aqueous secondary batteries, may be a concept that includes non-aqueous lithium-ion secondary batteries using a non-aqueous electrolyte and all-solid-state lithium-ion secondary batteries using a solid electrolyte.

[0022] For example, for secondary batteries mounted in vehicles, materials that can store a large amount of charge per unit volume are often selected as the active material. On the other hand, in this embodiment, the energy storage cell 112 is mounted on the aircraft 100. Therefore, it is preferable that the active material used in the energy storage cell 112 is a material that can store a large amount of charge per unit mass.

[0023] The mass energy density of the energy storage cell 112 is preferably 400 [Wh / kg-energy storage cell] or more, more preferably 500 [Wh / kg-energy storage cell] or more, more preferably 600 [Wh / kg-energy storage cell] or more, more preferably 650 [Wh / kg-energy storage cell] or more, and even more preferably 700 [Wh / kg-energy storage cell] or more. The mass energy density of the energy storage cell 112 may be 400 to 600 [Wh / kg-energy storage cell], 400 to 700 [Wh / kg-energy storage cell], or 500 to 700 [Wh / kg-energy storage cell]. This provides an energy storage cell particularly suitable for use as a power source for aircraft.

[0024] The volumetric energy density of the energy storage cell 112 is between 300 and 1200 [Wh / m³]. 3 - Energy storage cell] may be less than or equal to 400 to 1000 [Wh / m³] 3 - The energy storage cell may be less than or equal to 600 [Wh / m³]. When the energy storage cell 112 is mounted on the aircraft 100 as part of the power supply for the aircraft 100, the volumetric energy density of the energy storage cell 112 is 600 [Wh / m³]. 3 - Energy storage cell] may be less than or equal to 800 [Wh / m³] 3 - Energy storage cell] may be smaller than or equal to:

[0025] The capacity density of the energy storage cell 112 is preferably 150 [Ah / kg-energy storage cell] or more, preferably 180 [Ah / kg-energy storage cell] or more, and more preferably 200 [Ah / kg-energy storage cell] or more. This provides an energy storage cell that is particularly suitable for use as a power source for aircraft.

[0026] The energy storage cell 112 may have a mass energy density and a volume energy density within the above numerical range. This makes it possible to use energy storage cells that are relatively difficult to use as power sources for vehicles as power sources for aircraft. Details of the energy storage cell 112 will be described later.

[0027] In this embodiment, the power control circuit 120 controls the power input and output of the battery 110. The power control circuit 120 may control the power input and output of the battery 110 based on commands from the control device 160. The power control circuit 120 includes, for example, a plurality of switching elements that operate based on control signals from the control device 160.

[0028] In this embodiment, the electric motor 130 receives electrical energy from the battery 110 via the power control circuit 120. The electric motor 130 uses the electrical energy received from the battery 110 to rotate the propeller 140. As a result, the electric motor 130 can generate thrust for the aircraft 100 using the electrical energy stored in the battery cell 112.

[0029] In this embodiment, the sensor 150 measures various physical quantities related to the position and attitude of the aircraft 100. Examples of sensors for measuring various physical quantities related to the position and attitude of the aircraft 100 include a GPS signal receiver, an accelerometer, an angular acceleration sensor, and a gyroscope. The sensor 150 may also measure various physical quantities related to the state of the battery 110. Examples of sensors for measuring various physical quantities related to the state of the battery 110 include a temperature sensor, a current sensor, and a voltage sensor.

[0030] In this embodiment, the control device 160 controls the aircraft 100. The control device 160 may control the input and output of power from the battery 110 by controlling the power control circuit 120. For example, the control device 160 controls the output current, output voltage, input current, input voltage, etc., of the battery 110. As a result, the control device 160 can control the position and attitude of the aircraft 100. The control device 160 may control the position and attitude of the aircraft 100 by controlling the power control circuit 120 based on the output from the sensor 150.

[0031] The battery 110 may be an example of a secondary battery. The energy cell 112 may be an example of a secondary battery. The electric motor 130 may be an example of a propulsion force generating device.

[0032] Figure 2 schematically shows an example of a storage cell 112. In this embodiment, the details of the storage cell 112 will be explained using the case where the storage cell 112 is a coin-type non-aqueous secondary battery as an example. In this embodiment, the details of the storage cell 112 will be explained using the case where a region in which ions can move (sometimes called an ion permeable region) is formed in a part of the positive electrode 220 as an example.

[0033] [Energy storage cell] In this embodiment, the energy storage cell 112 comprises a positive electrode case 212, a negative electrode case 214, a sealant 216, and a metal spring 218. The energy storage cell 112 also comprises a positive electrode 220, a separator 230, a negative electrode 240, and an electrolyte 250. In this embodiment, the positive electrode 220 has a positive electrode current collector 222 and a positive electrode active material layer 224. In this embodiment, the negative electrode 240 has a negative electrode current collector 242 and a negative electrode active material layer 244.

[0034] In this embodiment, a space is formed inside the positive electrode case 212 and the negative electrode case 214 by assembling them. Inside the space formed by the positive electrode case 212 and the negative electrode case 214, a metal spring 218, a positive electrode 220, a separator 230, a negative electrode 240, and an electrolyte 250 are housed. The positive electrode 220, the separator 230, and the negative electrode 240 are fixed inside the positive electrode case 212 and the negative electrode case 214 by the repulsive force of the metal spring 218.

[0035] The positive electrode case 212 and the negative electrode case 214 are made of a conductive material having, for example, a disc-shaped thin plate form. In this embodiment, the sealant 216 seals the gap formed between the positive electrode case 212 and the negative electrode case 214. The sealant 216 includes an insulating material. The sealant 216 insulates the positive electrode case 212 and the negative electrode case 214.

[0036] [Positive electrode] As described above, in this embodiment, a region in the positive electrode 220 into which ions can move (sometimes referred to as an ion-permeable region) is formed. Examples of ion-permeable regions include (i) a region in which voids are formed into which electrolyte ions of the electrolyte solution 250 can enter, and (ii) a region in which a material (sometimes referred to as an ion-conducting material) with a larger transport rate of ions (for example, electrolyte ions of a secondary battery, metal ions that serve as carriers in a secondary battery) than the positive electrode active material of the positive electrode 220 is formed. The ion-permeable region is located, for example, in at least one of the positive electrode current collector 222 and the positive electrode active material layer 224. Details of the ion-permeable region will be described later.

[0037] In this embodiment, the positive electrode current collector 222 holds the positive electrode active material layer 224. Examples of materials for the positive electrode current collector 222 include conductive materials such as aluminum, stainless steel, nickel, titanium, or alloys thereof. Examples of shapes for the positive electrode current collector 222 include foil, mesh, punched metal, expanded metal, etc. The thickness of the positive electrode current collector 222 is not particularly limited, but for example, it is 3 to 200 μm. The thickness of the positive electrode current collector 222 may be 4 to 150 μm, 5 to 100 μm, or 6 to 20 μm.

[0038] In this embodiment, the positive electrode active material layer 224 is formed on at least one surface of the positive electrode current collector 222. The positive electrode active material layer 224 is in contact with at least a portion of the positive electrode current collector 222. The thickness of the positive electrode active material layer 224 may be 1 to 300 μm or 2 to 200 μm per side of the positive electrode current collector 222. The thickness of the positive electrode active material layer 224 may be 80 μm or more, greater than 80 μm, 100 μm or more, or 120 μm or more per side of the positive electrode current collector 222.

[0039] When the thickness of the positive electrode active material layer 224 on one side of the positive electrode current collector 222 is 80 μm or more, or exceeds 80 μm, the capacity density of the actually manufactured energy storage cell 112 may be less than 80% of the theoretical capacity density calculated from the mass of the positive electrode active material contained in the positive electrode active material layer 224. In such cases, the effect of forming an ion-permeable region inside the electrode becomes particularly pronounced.

[0040] According to one embodiment, an ion-permeable region is formed on the contact surface between the positive electrode current collector 222 and the positive electrode active material layer 224. This promotes the reaction between the positive electrode active material, which is located in the region of the surface of the positive electrode active material layer 224 covered by the positive electrode current collector 222, and electrolyte ions or carrier ions. As a result, the ratio of the capacity density of the actually manufactured energy storage cell 112 to the theoretical capacity density calculated from the mass of the positive electrode active material contained in the positive electrode active material layer 224 is improved. This results in the above ratio becoming, for example, 80% or more, thereby improving the capacity density of the energy storage cell 112.

[0041] In another embodiment, an ion-permeable region is formed inside the positive electrode active material layer 224, with a portion of it located on the surface of the positive electrode active material layer 224. This promotes the movement of ions between the surface of the positive electrode active material layer 224 and the interior of the positive electrode active material layer 224, thereby promoting the reaction between the positive electrode active material located inside the positive electrode active material layer 224 and electrolyte ions or carrier ions. As a result, the ratio of the actual capacity density of the manufactured energy storage cell 112 to the theoretical capacity density calculated from the mass of the positive electrode active material contained in the positive electrode active material layer 224 is improved. This results in the above ratio becoming, for example, 80% or more, thereby improving the capacity density of the energy storage cell 112.

[0042] The positive electrode active material layer 224 includes, for example, a positive electrode active material and a binder (sometimes referred to as a binder). The positive electrode active material layer 224 may further contain a conductive additive. The positive electrode active material layer 224 may also contain the ion-conducting material described above. Details of each material that can constitute the positive electrode layer will be described later.

[0043] (Cathode active material) The positive electrode active material layer 224 contains, for example, an organic compound or a salt thereof as the positive electrode active material. The above organic compound may be a crystalline or amorphous organic compound. When the positive electrode active material layer 224 contains a crystalline or amorphous organic compound or a salt thereof as the positive electrode active material, a dense film (for example, a film of the organic compound) may be formed on the surface of the positive electrode active material layer 224. When a dense film is formed on the surface of the positive electrode active material layer 224, the movement of ions between the surface of the positive electrode active material layer 224 and the interior of the positive electrode active material layer 224 is hindered. In such a case, the effect of forming an ion-permeable region inside the electrode becomes particularly pronounced.

[0044] The positive electrode active material may be a compound having a dithiadiazine group or a salt thereof. The compound having a dithiadiazine group may be an example of a crystalline or amorphous organic compound. The compound having a dithiadiazine group may be a compound represented by general formula (1) or a derivative of said compound.

[0045] [General formula (1)] [ka]

[0046] In general formula (1), R 1 and R 2 Each of these independently represents a hydrogen atom or an organic group. The above organic group may consist of one or more atoms selected from the group consisting of carbon, hydrogen, boron, nitrogen, oxygen, and sulfur. The above organic group may contain at least one of nitrogen and sulfur as a heteroatom. In general formula (1), n ​​represents the degree of polymerization of the dithiadiazine group. The degree of polymerization n may be a positive integer of 1 or more. The degree of polymerization n may be between 1 and 20. When the degree of polymerization n is between 1 and 20, the rigidity of the molecule is smaller and the free volume is relatively larger compared to when the degree of polymerization is significantly greater than 20. As a result, the rate of the redox reaction, which is a charge-discharge reaction, is higher compared to when the degree of polymerization is significantly greater than 20.

[0047] The above organic groups may be substituted or unsubstituted hydrocarbon groups. Examples of the above organic groups include substituted or unsubstituted alkyl groups, substituted or unsubstituted alkenyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted carboxyl groups, substituted or unsubstituted alkoxycarbonyl groups, substituted or unsubstituted acyl groups, substituted or unsubstituted acyloxy groups, substituted or unsubstituted aryl groups, substituted or unsubstituted aryloxy groups, substituted or unsubstituted heteroaryl groups, substituted or unsubstituted heteroaryloxy groups, substituted or unsubstituted ester groups, substituted or unsubstituted ether groups, substituted or unsubstituted amino groups, substituted or unsubstituted sulfonic acid groups, substituted or unsubstituted cyano groups, and substituted or unsubstituted thioether groups. The above organic groups may be monovalent groups having an ester bond (-COO-) or monovalent groups having an ether bond (-O-).

[0048] The compound having a dithiadiazine group may also be a compound having a dithiadiazine group and a thioamide group. The compound having a dithiadiazine group may be a compound represented by general formula (2), or a derivative of said compound. The positive electrode active material layer 224 may contain multiple types of compounds as the positive electrode active material. The multiple types of compounds may be compounds represented by general formula (2), and may include multiple types of compounds with different degrees of polymerization n.

[0049] [General formula (2)] [ka]

[0050] In general formula (2), n represents the degree of polymerization of the dithiadiazine group. The degree of polymerization n may be a positive integer greater than or equal to 1. The degree of polymerization n may be between 1 and 20. When the degree of polymerization n is between 1 and 20, the rigidity of the molecule is lower and the free volume is relatively larger compared to when the degree of polymerization is significantly greater than 20. As a result, the rate of the redox reaction, which is a charge-discharge reaction, is higher compared to when the degree of polymerization is significantly greater than 20.

[0051] There is no particular limitation on the method for synthesizing a compound having a dithiadiazine group or a salt thereof. A compound having a dithiadiazine group or a salt thereof can be synthesized, for example, by (i) a cyclization reaction of diamino-N-alkylethanethioamide and alkyliminochloromethanesulfenyl chloride, (ii) oxidative polymerization of dithiooxamide, or the like.

[0052] That the positive electrode active material layer 224 contains a compound having a dithiadiazine group or a salt thereof is confirmed, for example, by Raman mapping measurement of the surface of the positive electrode active material layer 224. Specifically, first, in any one of a charged state, a discharged state, and an intermediate state, the positive electrode 220 constituting the electricity storage cell 112 is taken out in a dry atmosphere. Next, the taken-out positive electrode 220 is washed and dried. Next, a region with a low content of conductive material on the surface of the positive electrode active material layer 224 is observed by Raman mapping method.

[0053] When the substance contained in the positive electrode active material layer 224 has a dithiadiazine group, a peak derived from an S-S bond at 530 to 545 cm -1 is observed at the position, and a peak derived from an N-N bond at 1150 to 1250 cm -1 is observed at the position. The polymerization degree n in general formula (2) can be confirmed by Raman mapping measurement of the surface of the positive electrode 220 taken out in a charged state. For example, the polymerization degree n can be measured by comparing the peak intensity derived from a C=S bond appearing at 1000 to 1100 cm -1 with the peak intensities of the above-described S-S bond and N-N bond.

[0054] According to the present embodiment, the positive electrode active material layer 224 contains a compound having a dithiadiazine group or a salt thereof. Thereby, the electricity storage cell 112 having large capacity density, small capacity reduction even after repeated charge and discharge, and good cycle characteristics can be obtained.

[0055] Compounds containing a dithiadiazine group are thought to form complex salts in battery electrode reactions. For example, chemical equation (A) shows an example of a charge-discharge reaction expected when an organic compound represented by general formula (2) with a degree of polymerization n of 1 is used as the electrode active material, and lithium ions are used as the cation of the electrolyte salt. For the sake of simplicity, the thioamide group is omitted from chemical equation (A).

[0056] [Chemical reaction equation (A)] [ka]

[0057] As shown in chemical equation (A), in compounds containing a dithiadiazine group, two electrons are involved in the reaction during charging and discharging. Specifically, the dithion moiety (CSSC) contained in the compound containing the dithiadiazine group is reduced to Li + It combines with Li during oxidation. + It releases.

[0058] The compound having dithiadiazine groups according to this embodiment can be oxidized and reduced with 2 or more electrons per dithiadiazine group, resulting in an electrode active material with good charge-discharge efficiency and high capacity density per unit mass. Furthermore, the compound having dithiadiazine groups according to this embodiment is stable even after repeated reactions and experiences little decrease in the number of electrons. As a result, it remains stable even after repeated charge-discharge cycles and exhibits good cycle characteristics. Consequently, stability during charge-discharge is improved, and a secondary battery with high energy density can be realized.

[0059] Furthermore, the positive electrode active material is not limited to compounds having a dithiadiazine group or salts thereof. If the energy storage cell 112 is a lithium-ion secondary battery or a lithium metal secondary battery, other examples of positive electrode active materials include LiMnO2, LiNiO2, LiCoO2, and Li(Mn x Ni 1-x )O2, Li(Mn x Co 1-x )O2, Li(Niy Co 1-y )O2, Li(Mn x Ni y Co 1-x-y )O2 and other layered oxides; Li2MnO3-LiNiO2, Li2MnO3-LiCoO2, Li2MnO3-Li(Ni y Co 1-y )O2 and other solid solutions; Li2MnSiO4, Li2NiSiO4, Li2CoSiO4, Li2(Mn x Ni 1-x )SiO4, Li2(Mn x Co 1-x )SiO4, Li2(Ni y Co 1-y )SiO4, Li2(Mn x Ni y Co 1-x-y )SiO4 and other silicates; LiMnBO3, LiNiBO3, LiCoBO3, Li(Mn x Ni 1-x )BO3, Li(Mn x Co 1-x )BO3, Li(Ni y Co 1-y )BO3, Li(Mn x Ni y Co 1-x-y )BO3 and other borates; V2O5; LiV3O6; MnO, etc. In the above formula, 0<x<1, 0<y<1, and 0<x+y<1. These positive electrode active materials may be used alone, or two or more types of positive electrode active materials may be combined.

[0060] When the electricity storage cell 112 is a sodium-ion secondary battery, other examples of the positive electrode active material include NaFeO2, NaNiO2, NaCoO2, NaMnO2, NaVO2, Na(Ni X Mn 1-X )O2, Na(Fe X Mn 1-X )O2, NaVPO4F, Na2FePO4F, Na3V2(PO4)3, etc. In the above formula, 0<x<1. These positive electrode active materials may be used alone, or two or more types of positive electrode active materials may be combined.

[0061] The content of the positive electrode active material in the positive electrode active material layer 224 is not particularly limited. The content of the positive electrode active material in the positive electrode active material layer 224 is determined, for example, according to the specifications of the secondary battery.

[0062] In one embodiment, if the positive electrode active material layer 224 does not contain a conductive additive as described later, the content of the positive electrode active material in the positive electrode active material layer 224 may be 40 to 99% by mass, 70 to 99% by mass, or 70 to 97% by mass. The above content may be 80 to 99% by mass, or 80 to 95% by mass. The above content may be 90 to 98% by mass, or 94 to 97% by mass.

[0063] In other embodiments, if the positive electrode active material layer 224 contains a conductive additive, the content of the positive electrode active material and the conductive additive in the positive electrode active material layer 224 may be 40 to 99% by mass, 70 to 99% by mass, or 70 to 97% by mass. If the positive electrode active material layer 224 contains a conductive additive, the content of the positive electrode active material in the positive electrode active material layer 224 may be 39.8 to 98.8% by mass, 69.8 to 98.8% by mass, or 69.8 to 96.8% by mass.

[0064] The content of compounds having dithiadiazine groups or salts thereof relative to the total positive electrode active material in the positive electrode active material layer 224 may be 10 to 95% by mass, or 50 to 95% by mass. The positive electrode active material contained in the positive electrode active material layer 224 may be substantially compounds having dithiadiazine groups or salts thereof.

[0065] When the content of a compound having a dithiadiazine group or a salt thereof relative to the total positive electrode active material is 10 to 95% by mass, a high-capacity energy storage cell 112 can be obtained compared to when the content is less than 10% by mass. When the content is 10 to 95% by mass, the amount of conductive additive and binder added can be reduced compared to when the content exceeds 95% by mass. This can suppress a decrease in the output of the energy storage cell 112.

[0066] (Binding agent) In this embodiment, the binder binds the materials constituting the positive electrode active material layer 224 (e.g., positive electrode active material, conductive additive, ion-conducting material, etc.) and maintains the electrode shape of the positive electrode 220. The type of binder is not particularly limited, but examples of binders include polyethylene, polyvinylidene fluoride (PVDF), polytetrafluoroethylene, polyhexafluoropropylene, polyethylene oxide, carboxymethylcellulose, polyacrylic acid, and styrene-butadiene rubber. These binders may be used alone or in combination of two or more types.

[0067] The binder content in the positive electrode active material layer 224 is not particularly limited. The binder content in the positive electrode active material layer 224 may be 1 to 60% by mass, 1 to 30% by mass, or 3 to 30% by mass. The above content may be 1 to 20% by mass, or 5 to 20% by mass. The above content may be 2 to 10% by mass, or 3 to 6% by mass.

[0068] In one embodiment, the remainder of the positive electrode active material layer 224 may be the positive electrode active material. In another embodiment, the remainder of the positive electrode active material layer 224 may be a mixture of the positive electrode active material and at least one of a conductive additive and an ionic conductive material. In yet another embodiment, the positive electrode active material layer 224 may contain substances other than the positive electrode active material, binder, conductive additive and ionic conductive material.

[0069] (Conductive additive) In this embodiment, the conductive additive reduces the resistance of the positive electrode 220. The type of conductive additive is not particularly limited as long as it has the desired electronic conductivity, but examples of conductive additives include carbon materials and conductive polymers. Examples of carbon materials include graphite, carbon black (e.g., acetylene black, Ketjenblack, etc.), coke, amorphous carbon, carbon fibers, carbon nanotubes, and graphene. Examples of conductive polymers include polyaniline, polypyrrole, polythiophene, polyacetylene, and polyacene. These conductive additives may be used individually or in combination of two or more types.

[0070] The content of the conductive additive in the positive electrode active material layer 224 is not particularly limited. As described above, the positive electrode active material layer 224 may not contain a conductive additive substantially. If the positive electrode active material layer 224 contains a conductive additive, the content of the conductive additive in the positive electrode active material layer 224 may be 80% by mass or less. The content of the conductive additive in the positive electrode active material layer 224 is preferably 0.2 to 20% by mass, more preferably 1 to 10% by mass, and even more preferably 2 to 6% by mass.

[0071] (Ionic conductive material) In this embodiment, the ion-conducting material is a material with a larger ion transport fraction than the positive electrode active material of the positive electrode 220. The ions may be cations of the electrolyte of the energy storage cell 112 (sometimes simply referred to as electrolyte ions), or metal ions that serve as carriers in the energy storage cell 112.

[0072] Ion-conducting materials have a conductivity of 1 × 10⁻¹⁶ at room temperature. -5 It may be a substance having an ionic conductivity of [S / cm] or higher, and at room temperature it is 1 × 10⁻⁶ -4 The material may have an ionic conductivity of [S / cm] or higher. Ion-conducting materials have an ionic conductivity of 1 × 10⁻⁶ at 60 degrees Celsius. -4 It may be a substance having an ionic conductivity of [S / cm] or higher, and at 60 degrees Celsius, it is 5 × 10 -4 The material may have an ionic conductivity of [S / cm] or higher.

[0073] In one embodiment, the ion-conducting material includes (i) various electrolytes, (ii) various ionic liquids in which cations and anions are combined, (iii) glycol ethers, and / or (iv) chain sulfones. Examples of various electrolytes include at least one of polymer gel electrolytes, polymer electrolytes, and solid electrolytes. Examples of glycol ethers include (i) polyethylene glycol (sometimes referred to as polyethylene oxide, polyoxyethylene, etc.), (ii) glycol diethers, and (iii) crown ethers. The glycol diether may be a symmetric glycol diether. Examples of symmetric glycol diethers include gums.

[0074] For example, the ion-conducting material includes at least one of a polymer gel electrolyte, a polymer electrolyte, and a solid electrolyte. The ion-conducting material may be substantially at least one of a polymer gel electrolyte, a polymer electrolyte, and a solid electrolyte.

[0075] In other embodiments, the ion-conducting material comprises a mixture or reactant of the positive electrode active material with at least one of a nonionic surfactant and a stable radical compound. The ion-conducting material may substantially be a mixture or reactant of the positive electrode active material with at least one of a nonionic surfactant and a stable radical compound. This increases the free volume in the positive electrode mixture. As a result, the self-exchange reaction of the positive electrode active material is promoted.

[0076] As described above, in this embodiment, an organic compound is used as the positive electrode active material. The hydrogen atoms or functional groups of the organic compound used as the positive electrode active material may react with at least one of the hydrogen atoms or functional groups of the nonionic surfactant and the stable radical compound to produce the above-mentioned reactants.

[0077] The molecular weight of the nonionic surfactant and the stable radical compound may be 50 to 2000, 100 to 1000, 150 to 500, or 150 to 250. Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, and polyoxyethylene sorbitan fatty acid esters. Examples of stable radical compounds include 2,2,6,6-tetramethylpiperidine 1-oxyl, galbinoxyl radical, and 2,2-diphenyl-1-picrylhydrazyl. When the main component of the positive electrode active material of positive electrode 220 is a compound having a dithiadiazine group or a salt thereof, the nonionic surfactant may be polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, or a combination thereof, and the stable radical compound may be 2,2,6,6-tetramethylpiperidine 1-oxyl, galbinoxyl radical, or a combination thereof.

[0078] In yet another embodiment, the ion-conducting material comprises a reaction product of a binder and at least one of a nonionic surfactant and a stable radical compound. The ion-conducting material may be a reaction product of a binder and at least one of a nonionic surfactant and a stable radical compound. This increases the free volume in the positive electrode mixture. As a result, the self-exchange reaction of the positive electrode active material is promoted.

[0079] As described above, in this embodiment, an organic compound is used as a binder. The hydrogen atoms or functional groups of the organic compound used as a binder may react with the hydrogen atoms or functional groups of at least one of the nonionic surfactant and the stable radical compound to produce the above-mentioned reactants. The above-mentioned nonionic surfactant and / or stable radical compound may have the same configuration as the nonionic surfactant and / or stable radical compound described in relation to the positive electrode active material.

[0080] When an ion-permeable region having an ion-conducting material is formed in the positive electrode active material layer 224, the mass of the ion-conducting material included in the ion-permeable region formed in the positive electrode active material layer 224 may be 50% or less, 10% or less, or 1% or less of the mass of the positive electrode active material layer 224. The mass of the positive electrode active material layer 224 mentioned above includes the mass of the ion-permeable region arranged in the positive electrode active material layer 224.

[0081] When the mass of the ion-conducting material is 50% or less of the mass of the positive electrode active material layer 224, the increase in capacity density due to the effect of promoting electrolyte ion movement associated with an increase in the mass of the ion-conducting material is greater than the decrease in capacity density due to the decrease in positive electrode active material associated with an increase in the mass of the ion-conducting material. As a result, the capacity density of the energy storage cell 112 increases.

[0082] [Method for manufacturing the positive electrode active material layer 224] In one embodiment, the positive electrode active material layer 224 is formed, for example, by applying a paste (sometimes referred to as a slurry) containing the materials constituting the positive electrode active material layer 224 and an organic solvent onto at least one surface of the positive electrode current collector 222, and then drying the paste. The type of organic solvent and / or the mixing ratio of the positive electrode active material to the organic solvent can be arbitrarily set considering the required characteristics and productivity of the secondary battery.

[0083] The types of organic solvents listed above are not particularly limited, but examples include basic solvents, non-aqueous solvents, and protic solvents. Examples of basic solvents include dimethyl sulfoxide, dimethylformamide, 1-methyl-2-pyrrolidone (sometimes called N-methylpyrrolidone, NMP, etc.), propylene carbonate, diethyl carbonate, dimethyl carbonate, and γ-butyrolactone. Examples of non-aqueous solvents include acetonitrile, tetrahydrofuran, nitrobenzene, and acetone. Examples of protic solvents include methanol, ethanol, and water.

[0084] The structure of the positive electrode active material layer 224 is not particularly limited. In one embodiment, the positive electrode active material layer 224 is composed of a single layer. In other embodiments, the positive electrode active material layer 224 is composed of multiple layers. The multiple layers may have different compositions from each other, or some of the multiple layers may have the same composition. Some of the multiple layers may not substantially contain positive electrode active material.

[0085] Some of the layers may be connected by penetrating other layers. For example, a positive electrode active material layer 224 having multiple stacked layers can be fabricated by sequentially applying multiple types of paste with different coating patterns. Alternatively, when the positive electrode active material layer 224 has a first layer, a second layer, and a third layer stacked in order, an opening may be formed in the second layer, and the first and third layers may be connected through this opening. The opening in the second layer may be filled with the material constituting the first or third layer.

[0086] In other embodiments, the positive electrode active material layer 224 is manufactured without using the paste described above. The positive electrode active material layer 224 is formed, for example, by mixing the materials constituting the positive electrode active material layer 224, molding them into a sheet, and then pressing the sheet-like mixture onto at least one surface of the positive electrode current collector 222.

[0087] [Ion permeable region] In this embodiment, an ion-permeable region is formed in a part of the positive electrode 220. The ion-permeable region is formed, for example, in at least one of the positive electrode current collector 222 and the positive electrode active material layer 224. As described above, examples of ion-permeable regions include (i) a region in which voids are formed that allow electrolyte ions of the electrolyte solution 250 to penetrate, and (ii) a region in which an ion-conducting material is formed.

[0088] In one embodiment, the ion-permeable region may be a recess disposed on the surface of the positive electrode current collector 222. The recess may extend from the surface of the positive electrode current collector 222 toward the interior of the positive electrode current collector 222. The recess may have a hole shape, a groove shape, a depression shape, or a combination thereof. The ion-permeable region may also be an ion-conducting material disposed in at least a part of the recess. A hole-shaped recess may or may not penetrate the positive electrode current collector 222.

[0089] If the above-mentioned recess has a pore shape, the diameter of the pore may be 1 μm or more, or 0.1 μm or more. The diameter of the above-mentioned pore may be 0.01 μm to 5 μm, or 0.01 μm to 1 μm. As a result, if the energy storage cell 112 is equipped with an electrolyte 250, a portion of the electrolyte 250 may penetrate into the interior of the ion permeable region. The electrolyte 250 may fill all of the voids in the ion permeable region, or it may fill only a portion of the voids in the ion permeable region.

[0090] The diameter of the hole described above can be calculated, for example, by taking the area of ​​the hole opening as the diameter of a circle with an equivalent area. The diameter of the hole described above can also be calculated, for example, by observing a specific location on the sample with a scanning electron microscope (SEM).

[0091] In other embodiments, the ion-permeable region may be a recess disposed in the positive electrode active material layer 224. The recess may extend from the surface of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. The recess may have a hole shape, a groove shape, a depression shape, or a combination thereof. The ion-permeable region may also be an ion-conducting material disposed in at least a portion of the recess. A hole-shaped recess may penetrate the positive electrode active material layer 224, but may not penetrate the positive electrode current collector 222.

[0092] The ion-permeable region is positioned to be in contact with the electrolyte 250 or electrolyte 330 as described in relation to Figure 3, and with the surface of the positive electrode active material layer 224. For example, the ion-permeable region is positioned such that when the positive electrode 220 is incorporated into the energy storage cell 112, the ion-permeable region is in contact with both the electrolyte 250 or electrolyte 330 and the surface of the positive electrode active material layer 224. The surface of the positive electrode active material layer 224 may be (i) the surface on the side of the positive electrode current collector 222, (ii) the surface on the side of the separator 230 or negative electrode 240, or (iii) the surface of the surface (sometimes referred to as the side) connecting the surface on the side of the positive electrode current collector 222 and the surface on the side of the separator 230.

[0093] In one embodiment, the ion-permeable region is a recess in the positive electrode active material layer 224 or an ion-conducting material disposed in the recess, with one end of the ion-permeable region located on the surface of the positive electrode active material layer 224 or a plane substantially identical to that surface, and the other end of the ion-permeable region located inside the positive electrode active material layer 224. The recess may have a hole shape, a groove shape, a depression shape, or a combination thereof. When the ion-permeable region is the recess described above, an opening is formed on the surface of the positive electrode active material layer 224. In this case, one end of the ion-permeable region is located on a plane substantially identical to the surface of the positive electrode active material layer 224.

[0094] According to this embodiment, when the positive electrode 220 is incorporated into the energy storage cell 112, electrolyte ions can move between the ion-permeable region and the electrolyte 250 or electrolyte 330 present on or near the surface of the positive electrode active material layer 224. Furthermore, electrolyte ions can move between the ion-permeable region and the positive electrode active material present on the inner surface of the recess of the positive electrode active material layer 224. As described above, electrolyte ions can move within the ion-permeable region. This allows the positive electrode active material placed inside the positive electrode active material layer 224 to function effectively.

[0095] In other embodiments, the ion-permeable region is a recess extending from the side surface of the positive electrode current collector 222 toward the interior of the positive electrode current collector 222, or an ion-conductive material disposed in the recess, wherein one end of the ion-permeable region is located on the surface of the positive electrode active material layer 224, and the other end of the ion-permeable region is located inside the positive electrode current collector 222. The recess may have a hole shape, a groove shape, a depression shape, or a combination thereof.

[0096] According to this embodiment, when the positive electrode 220 is incorporated into the energy storage cell 112, electrolyte ions can move between the ion-permeable region and the electrolyte 250 or electrolyte 330 present on or near the side surface of the positive electrode current collector 222. Furthermore, electrolyte ions can move between the ion-permeable region and the positive electrode active material present on the surface of the positive electrode active material layer 224 facing the positive electrode current collector 222. As described above, electrolyte ions can move within the ion-permeable region. This allows the positive electrode active material placed in the region of the positive electrode active material layer 224 covered by the positive electrode current collector 222 to function effectively.

[0097] In yet another embodiment, the ion-permeable region is a recess that penetrates the positive electrode current collector 222 and reaches the surface of the positive electrode active material layer 224, or an ion-conductive material disposed in the recess, wherein one end of the ion-permeable region is located on the surface of the positive electrode active material layer 224, and the other end of the ion-permeable region is located on the surface of the positive electrode current collector 222 or on a plane substantially identical to that surface. The recess may have a hole shape, a groove shape, a depression shape, or a combination thereof. When the ion-permeable region is the above-mentioned recess, an opening is formed on the surface of the positive electrode current collector 222. In this case, the other end of the ion-permeable region is located on a plane substantially identical to the surface of the positive electrode current collector 222.

[0098] According to this embodiment, when the positive electrode 220 is incorporated into the energy storage cell 112, electrolyte ions can move between the ion-permeable region and the electrolyte 250 or electrolyte 330 present on or near the surface of the positive electrode current collector 222. Furthermore, electrolyte ions can move between the ion-permeable region and the positive electrode active material present on the surface of the positive electrode active material layer 224 facing the positive electrode current collector 222. As described above, electrolyte ions can move within the ion-permeable region. This allows the positive electrode active material placed in the region of the positive electrode active material layer 224 covered by the positive electrode current collector 222 to function effectively.

[0099] The volume of the ion-permeable region may be 50% or less of the volume of the positive electrode active material layer 224 (including the volume of the ion-permeable region arranged in the positive electrode active material layer 224), 10% or less of that volume, or 1% or less of that volume. This increases the capacity density of the energy storage cell 112.

[0100] The mass of the ion-permeable region may be 50% or less of the mass of the positive electrode active material layer 224 (including the mass of the ion-permeable region arranged in the positive electrode active material layer 224), 10% or less of that mass, or 1% or less of that mass. This increases the capacity density of the energy storage cell 112.

[0101] [Separator] In this embodiment, the separator 230 separates the positive electrode 220 and the negative electrode 240. The separator 230 ensures ionic conductivity between the positive electrode 220 and the negative electrode 240, for example, by holding the electrolyte. The material of the separator 230 is not particularly limited, but examples of materials for the separator 230 include polyethylene, polypropylene, ethylene-propylene copolymer, or laminates thereof, or composites of these with glass, ceramic, etc. Examples of the shape of the separator 230 include microporous film, nonwoven fabric, filter, etc. The thickness of the separator 230 is not particularly limited, but is preferably 10 to 50 μm. The aperture ratio of the separator 230 is not particularly limited, but is preferably 30 to 70%.

[0102] [Negative electrode] In this embodiment, the negative electrode current collector 242 holds the negative electrode active material layer 244. Examples of materials for the negative electrode current collector 242 include copper, aluminum, stainless steel, nickel, titanium, or alloys thereof. The negative electrode current collector 242 may comprise a resin support layer and a metal layer disposed on the surface of the support layer. Examples of the resin include polyethylene, polypropylene, polyethylene terephthalate, and polyimide. The metal layer may be made of copper, aluminum, stainless steel, nickel, titanium, or alloys thereof. The metal layer may include layers made of copper, aluminum, stainless steel, nickel, titanium, or alloys thereof. The metal layer may be a foil or a plated layer.

[0103] When lithium metal is used as the negative electrode active material, the lithium metal can also act as a current collector. Therefore, if the energy storage cell 112 is a lithium metal secondary battery, the energy storage cell 112 does not need to be equipped with a negative electrode current collector 242.

[0104] Examples of the shape of the negative electrode current collector 242 include foil, mesh, punched metal, and expanded metal. The thickness of the negative electrode current collector 242 is not particularly limited, but may be 5 to 200 μm. Preferably, the thickness of the negative electrode current collector 242 is 6 to 20 μm.

[0105] In this embodiment, the negative electrode active material layer 244 is formed on at least one surface of the negative electrode current collector 242. The thickness of the negative electrode active material layer 244 may be 1 to 300 μm or 2 to 200 μm per side of the negative electrode current collector 242. The negative electrode active material layer 244 includes, for example, a negative electrode active material and a binder. The negative electrode active material layer 244 may also include a conductive additive.

[0106] In one embodiment, the negative electrode active material layer 244 is formed by applying a paste containing the materials constituting the negative electrode active material layer 244 and an organic solvent onto at least one surface of the negative electrode current collector 242, and then drying the paste. The type of organic solvent and / or the mixing ratio of the negative electrode active material to the organic solvent can be arbitrarily set considering the required characteristics and productivity of the secondary battery.

[0107] The types of organic solvents listed above are not particularly limited, but examples include basic solvents, non-aqueous solvents, and protic solvents. Examples of basic solvents include dimethyl sulfoxide, dimethylformamide, 1-methyl-2-pyrrolidone (sometimes called N-methylpyrrolidone, NMP, etc.), propylene carbonate, diethyl carbonate, dimethyl carbonate, and γ-butyrolactone. Examples of non-aqueous solvents include acetonitrile, tetrahydrofuran, nitrobenzene, and acetone. Examples of protic solvents include methanol, ethanol, and water.

[0108] In another embodiment, the negative electrode active material layer 244 is manufactured without using the paste described above. The negative electrode active material layer 244 is formed, for example, by mixing the materials constituting the negative electrode active material layer 244, molding them into a sheet, and then pressing the sheet-like mixture onto at least one surface of the negative electrode current collector 242.

[0109] (Negative electrode active material) The negative electrode active material layer 244 contains one or more negative electrode active materials. Examples of negative electrode active materials include (i) graphite, (ii) difficult-to-sinter carbon or difficult-to-graphitize carbon, (iii) tin, silicon and alloys containing these, and (iv) SiO. When materials such as (i) graphite, (ii) difficult-to-sinter carbon or difficult-to-graphitize carbon, (iii) tin, silicon and alloys containing these, and (iv) SiO are used as negative electrode active materials, these materials may be pre-doped with lithium.

[0110] The negative electrode active material may be a lithium-containing material such as metallic lithium or a lithium alloy. For example, if the energy storage cell 112 is a lithium metal secondary battery, metallic lithium is used as the negative electrode. These negative electrode active materials may be used individually, or two or more negative electrode active materials may be combined.

[0111] The negative electrode active material layer 244 may contain lithium metal foil. This supplies lithium to the energy storage cell 112. The thickness of the lithium metal foil may be 1 to 300 μm, 2 to 200 μm, or 3 to 100 μm. The thickness and / or mass of the lithium metal foil may be determined according to the content of the positive electrode active material in the positive electrode active material layer 224.

[0112] If the energy storage cell 112 is a sodium-ion secondary battery, other examples of negative electrode active materials include (i) graphite, (ii) poorly sinterable carbon or poorly graphitizable carbon, (iii) tin, silicon and alloys containing these, and (iv) titanium oxide. The negative electrode active material may also be a sodium-containing material such as metallic sodium or sodium alloy. These negative electrode active materials may be used individually or in combination of two or more types.

[0113] (Binding agent) In this embodiment, the binder binds the materials constituting the negative electrode active material layer 244 (e.g., negative electrode active material, conductive additive, etc.) and maintains the electrode shape of the negative electrode 240. The type of binder is not particularly limited, but examples of binders include polyethylene, polyvinylidene fluoride (PVDF), polytetrafluoroethylene, polyhexafluoropropylene, polyethylene oxide, carboxymethylcellulose, polyacrylic acid, and styrene-butadiene rubber. These binders may be used alone or in combination of two or more types.

[0114] (Conductive additive) In this embodiment, the conductive additive reduces the resistance of the negative electrode 240. The type of conductive additive is not particularly limited as long as it has the desired electronic conductivity, but examples of conductive additives include carbon materials and conductive polymers. Examples of carbon materials include graphite, carbon black (e.g., acetylene black, Ketjen black, etc.), coke, amorphous carbon, carbon fibers, carbon nanotubes, and graphene. Examples of conductive polymers include polyaniline, polypyrrole, polythiophene, polyacetylene, and polyacene. These conductive additives may be used individually or in combination of two or more types.

[0115] (Composition of the negative electrode active material layer 244) The composition of the negative electrode active material layer 244 is appropriately determined according to the specifications of the secondary battery. The content of the negative electrode active material in the negative electrode active material layer 244 may be the same as the content of the positive electrode active material in the positive electrode active material layer 224. The content of the binder in the negative electrode active material layer 244 may be the same as the content of the positive electrode active material in the positive electrode active material layer 224. The content of the conductive additive in the negative electrode active material layer 244 may be the same as the content of the positive electrode active material in the positive electrode active material layer 224.

[0116] [Electrolytes] In this embodiment, the electrolyte 250 facilitates ionic conduction between the positive electrode active material and the negative electrode active material via the ions of the electrolyte contained in the electrolyte 250. Examples of the electrolyte 250 include a liquid obtained by dissolving an electrolyte salt in an organic solvent, and an ionic liquid combining anions and cations. The ionic conductivity of the electrolyte 250 is 10 at room temperature. -5 ~10 -1 It can be around [S / cm].

[0117] According to this embodiment, a non-aqueous electrolyte is used as the electrolyte 250. Known organic electrolytes can be used as the non-aqueous electrolyte. For example, if the energy storage cell 112 is a lithium-ion secondary battery or a lithium metal secondary battery, the electrolyte 250 is a solution obtained by dissolving (ii) a lithium salt such as lithium perchlorate or LiPF6 in a solvent consisting of one or more such as ethylene carbonate, dimethyl carbonate, or diethyl carbonate.

[0118] The non-aqueous electrolyte contains, for example, a metal salt and a non-aqueous solvent. The non-aqueous electrolyte may also contain a hydrofluoroether. The presence of a hydrofluoroether in the electrolyte 250 makes it easier for the electrolyte 250 to permeate the positive electrode active material layer 224, the separator 230, etc.

[0119] Examples of metal salts include sodium salts and lithium salts. Examples of sodium salts include inorganic sodium salts such as NaPF6, NaBF4, NaClO4, and NaAsF6, and organic sodium salts such as NaCF3SO3, NaN(CF3SO2)2, NaN(C2F5SO2)2, and NaC(CF3SO2)3. Examples of lithium salts include inorganic lithium salts such as LiPF6, LiBF4, LiClO4, and LiAsF6, and organic lithium salts such as LiCF3SO3, LiN(CF3SO2)2, LiN(C2F5SO2)2, and LiC(CF3SO2)3.

[0120] Examples of non-aqueous solvents include ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), butylene carbonate (BC), fluoroethylene carbonate (FEC), γ-butyrolactone, sulfolane, acetonitrile, 1,2-dimethoxymethane, 1,3-dimethoxypropane, diethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, and mixtures thereof. Examples of hydrofluoroethers include 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether and 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxybutane.

[0121] The concentration of sodium salt in the non-aqueous electrolyte is not particularly limited, but may be in the range of 0.5 to 4.0 mol / L. The concentration of sodium salt may also be in the range of 0.7 mol / L to 2.0 mol / L, or in the range of 1.0 mol / L to 1.5 mol / L. The concentration of lithium salt in the non-aqueous electrolyte is not particularly limited, but may be in the range of 0.5 to 4.0 mol / L. The concentration of lithium salt may also be in the range of 0.7 mol / L to 2.0 mol / L, or in the range of 1.0 mol / L to 1.5 mol / L.

[0122] [An example of an alternative embodiment] In this embodiment, the details of the energy storage cell 112 were described using the case where the energy storage cell 112 is a coin-type secondary battery as an example. However, the type and structure of the energy storage cell 112 are not limited to this embodiment. In other embodiments, the energy storage cell 112 may be a cylindrical battery comprising a wound electrode body in which a positive electrode, a separator, and a negative electrode are wound in a spiral shape. In yet another embodiment, the energy storage cell 112 may be a laminated battery in which a laminated electrode body, in which positive and negative electrodes are alternately stacked with a separator in between, is sealed with a laminate.

[0123] In this embodiment, the details of the energy storage cell 112 were described as an example in which the negative electrode 240 has a negative electrode current collector 242 and a negative electrode active material layer 244. However, the negative electrode of the energy storage cell 112 is not limited to this embodiment. In other embodiments, for example, if the energy storage cell 112 is a lithium metal secondary battery, metallic lithium can be used as the negative electrode.

[0124] In this embodiment, an example of a storage cell 112 was described using the case where the electrolyte solution 250 is used as the electrolyte for the storage cell 112. However, the electrolyte for the storage cell 112 is not limited to this embodiment.

[0125] In other embodiments, a solid electrolyte or a gel electrolyte may be used as the electrolyte for the energy storage cell 112. A polymer compound containing an electrolyte salt may also be used as the electrolyte for the energy storage cell 112.

[0126] Examples of solid electrolytes include inorganic solid electrolytes such as Li2S-P2S5 systems and Li2S-GeS2-P2S5 systems. Polymer compounds may also be used as solid electrolytes. Examples of polymer compounds that can be used as solid electrolytes include vinylidene fluoride polymers, acrylonitrile polymers, polyethylene oxide, ethylene oxide-propylene oxide copolymers, and polymers of their acrylates and / or methacrylates.

[0127] Examples of vinylidene fluoride polymers include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-ethylene copolymer, vinylidene fluoride-monofluoroethylene copolymer, vinylidene fluoride-trifluoroethylene copolymer, vinylidene fluoride-tetrafluoroethylene copolymer, and vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene ternary copolymer. Examples of acrylonitrile polymers include acrylonitrile-methyl methacrylate copolymer, acrylonitrile-methyl acrylate copolymer, acrylonitrile-ethyl methacrylate copolymer, acrylonitrile-ethyl atarylate copolymer, acrylonitrile-methacrylic acid copolymer, acrylonitrile-acrylic acid copolymer, and acrylonitrile-vinyl acetate copolymer.

[0128] In this embodiment, an example of a storage cell 112 was described, in which a region in which ions can move (sometimes referred to as an ion-permeable region) is formed in a part of the positive electrode 220. However, the storage cell 112 is not limited to this embodiment. In other embodiments, an ion-permeable region may be formed in a part of the negative electrode 240.

[0129] In this embodiment, an example of a storage cell 112 was described using the case where a non-aqueous electrolyte is used as the electrolyte 250. However, the storage cell 112 is not limited to this embodiment. In other embodiments, an ionic liquid may be used as the electrolyte 250.

[0130] Examples of ionic liquid cations include imidazolium, ammonium, alkylpyridinium, dialkylpyrrolidinium, tetraalkylphosphonium, and trialkylsulfonium. Examples of imidazolium include 2-ethylimidazolium, 3-propylimidazolium, 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, and 1,3-dimethylimidazolium. Examples of ammonium include diethylmethylammonium, tetrabutylammonium, cyclohexyltrimethylammonium, methyltri-n-octylammonium, triethyl(2-methoxyethoxymethyl)ammonium, benzyldimethyltetradecylammonium, and benzyltrimethylammonium.

[0131] Examples of anions in ionic liquids include halide anions, boride anions, amide anions or imide anions, sulfate anions or sulfonate anions, phosphate anions, antimony anions, lactates, nitrate ions, and trifluoroacetates. Examples of halide anions include Cl - , Br - , I - Examples include BF4. - , B(CN)4 - B(C2O4)2 - Examples include (CN)2N as an amide anion or imide anion. - [N(CF3)2] - [N(SO2CF3)2] - Examples include RSO3. - , RSO4 - , R f SO3 - , R f SO4 - (R indicates an aliphatic hydrocarbon group or an aromatic hydrocarbon group) f This indicates a fluorine-containing halogenated hydrocarbon group. Examples include ). As for phosphate anions, R f 2P(O)O - PF6- , R f 3PF3 - Examples include (R f (This indicates a fluorine-containing halogenated hydrocarbon group). SbF6 is an example of an antimony anion.

[0132] [Other examples of energy storage cell 112] Figure 3 schematically shows another example of the energy storage cell 112. The energy storage cell 112 described in relation to Figure 3 has a similar configuration to the energy storage cell 112 described in relation to Figure 2, except that the positive electrode 220 and the negative electrode 240 are arranged via a solid or gel-like electrolyte 330 instead of a separator 230, and that there is no electrolyte 250 inside the energy storage cell 112.

[0133] Examples of solid electrolytes include inorganic solid electrolytes such as Li2S-P2S5 systems and Li2S-GeS2-P2S5 systems, as explained in relation to Figure 2. Polymer compounds may be used as solid electrolytes. Examples of polymer compounds that can be used as solid electrolytes include vinylidene fluoride polymers, acrylonitrile polymers, polyethylene oxide, ethylene oxide-propylene oxide copolymers, and polymers of their acrylates and / or methacrylates. Known gel electrolytes may be used as gel electrolytes.

[0134] [Details of the ion permeable region] Figures 4, 5, 6, 7, and 8 illustrate the details of the ion-permeable region. Figure 4 schematically shows an example of a cross-section of the positive electrode 220. Figure 5 schematically shows an example of a cross-section of the positive electrode active material layer 224. Figure 6 schematically shows another example of a cross-section of the positive electrode active material layer 224. Figure 7 schematically shows another example of a cross-section of the positive electrode 220. Figure 8 schematically shows yet another example of a cross-section of the positive electrode 220.

[0135] As shown in Figure 4, in this embodiment, the positive electrode current collector 222 has a first surface 422, a second surface 424, and a side surface 426. In this embodiment, the positive electrode active material layer 224 has a first surface 442, a second surface 444, and a side surface 446. In this embodiment, one or more ion-permeable regions 460 are formed in the positive electrode active material layer 224. In this embodiment, the ion-permeable region 460 includes one or more ion-permeable regions 462 and one or more ion-permeable regions 464.

[0136] In this embodiment, the positive electrode current collector 222 and the positive electrode active material layer 224 are arranged such that the first surface 422 of the positive electrode current collector 222 and the first surface 442 of the positive electrode active material layer 224 are in contact. In this embodiment, the second surface 424 is the surface opposite to the first surface 422, and the side surface 426 connects the first surface 422 and the second surface 424. In this embodiment, the second surface 444 is the surface opposite to the first surface 442, and the side surface 446 connects the first surface 442 and the second surface 444.

[0137] In this embodiment, each of the one or more ion-permeable regions 462 extends from the second surface 444 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. The ion-permeable region 462 may be a recess extending from the second surface 444 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. The recess may have a hole shape, a groove shape, a depression shape, or a combination thereof. The ion-permeable region 462 may be an ion-conducting material disposed in at least a part of the recess. The first portion of the ion-conducting material is in contact with the inner surface of the recess. The second portion of the ion-conducting material is disposed on or near the second surface 444. The second portion may be a different portion from the first portion.

[0138] In this embodiment, each of the one or more ion-permeable regions 464 penetrates the positive electrode active material layer 224 in the thickness direction (z direction in the figure) of the positive electrode active material layer 224. The ion-permeable region 464 may be a through-hole penetrating the positive electrode active material layer 224. The ion-permeable region 464 may be an ion-conducting material disposed in at least a portion of the above-mentioned through-hole. The first portion of the above-mentioned ion-conducting material is in contact with the inner surface of the above-mentioned through-hole. The second portion of the above-mentioned ion-conducting material is disposed on or near the second surface 444. The second portion may be a different portion from the first portion.

[0139] Figure 5 illustrates other features of the ion-permeable regions formed in the positive electrode active material layer 224. As shown in Figure 5, in this embodiment, the positive electrode active material layer 224 has one or more ion-permeable regions 462, one or more ion-permeable regions 464, one or more ion-permeable regions 562, one or more ion-permeable regions 572, one or more ion-permeable regions 574, one or more ion-permeable regions 582, and one or more ion-permeable regions 584.

[0140] In this embodiment, each of the one or more ion-permeable regions 562 extends from the second surface 444 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. Each of the one or more ion-permeable regions 562 differs from the ion-permeable region 462 described in relation to Figure 4 in that the direction of extension is inclined with respect to the thickness direction of the positive electrode active material layer 224 (the z direction in the figure). With respect to features other than the above-mentioned differences, each of the one or more ion-permeable regions 562 may have the same configuration as the ion-permeable region 462. In other embodiments, the ion-permeable region 562 may penetrate the positive electrode active material layer 224.

[0141] In this embodiment, each of the one or more ion-permeable regions 572 differs from the ion-permeable region 462 described in relation to Figure 4 in that it extends from the side surface 446 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. With respect to features other than the above-mentioned differences, each of the one or more ion-permeable regions 572 may have the same configuration as the ion-permeable region 462.

[0142] In this embodiment, one or more ion-permeable regions 574 differ from the ion-permeable regions 464 described in relation to Figure 4 in that they penetrate the positive electrode active material layer 224 in the width direction (x direction in the figure) of the positive electrode active material layer 224. Regarding features other than the above-mentioned differences, each of the one or more ion-permeable regions 574 may have the same configuration as the ion-permeable region 464.

[0143] In this embodiment, each of the one or more ion-permeable regions 582 extends from a part of the ion-permeable region 464 toward the interior of the positive electrode active material layer 224. One end of the ion-permeable region 582 is located on the inner surface of the ion-permeable region 464. The other end of the ion-permeable region 582 may be located inside the positive electrode active material layer 224 or on the surface of the positive electrode active material layer 224. In other embodiments, the ion-permeable region 582 may extend from a part of an ion-permeable region other than the ion-permeable region 464 toward the interior of the positive electrode active material layer 224.

[0144] In this embodiment, each of the one or more ion-permeable regions 584 connects a plurality of ion-permeable regions 462 within the positive electrode active material layer 224. In other embodiments, the ion-permeable region 584 may connect any type of ion-permeable region. The ion-permeable region 584 may connect any number of ion-permeable regions.

[0145] According to this embodiment, the ion-permeable regions 462, 464, 582, and 584 promote the movement of electrolyte ions between the electrolyte 250 or electrolyte 330 disposed on or near the second surface 444 and the positive electrode active material disposed on the inner surface of each ion-permeable region. According to this embodiment, the ion-permeable regions 572 and 574 promote the movement of electrolyte ions between the electrolyte 250 disposed on or near the side surface 446 and the positive electrode active material disposed on the inner surface of each ion-permeable region.

[0146] Figure 6 illustrates other features of the ion-permeable region formed in the positive electrode active material layer 224. As shown in Figure 6, in this embodiment, the positive electrode active material layer 224 includes a plurality of particles 640. Each of the plurality of particles 640 includes a positive electrode active material and a binder. At least a portion of the plurality of particles 640 may include a positive electrode active material, a binder, and at least one of a conductive additive and an ion-conducting material.

[0147] According to this embodiment, one or more voids 660 are formed between a plurality of particles. Each of the one or more voids 660 extends from the surface of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224.

[0148] In one embodiment, the void 660 extends from the first surface 442 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. In another embodiment, the void 660 extends from the second surface 444 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. In yet another embodiment, the void 660 extends from the side surface 446 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224. In yet another embodiment, the void 660 penetrates the positive electrode active material layer 224. The void 660 may penetrate the positive electrode active material layer 224 in the thickness direction, the width direction, or the length direction (y direction, not shown) of the positive electrode active material layer 224.

[0149] Figure 7 illustrates other features of the ion-permeable region formed in the positive electrode 220. Figure 7 schematically shows examples of the first cross-section 702 and the second cross-section 704 of the positive electrode 220. The first cross-section 702 may be an example of a cross-section of the positive electrode 220 when the positive electrode 220 is cut in a section substantially parallel to the stacking direction of the constituent members of the positive electrode 220 (the z direction in the figure). The first cross-section 702 may be B-B' in the second cross-section 704. The second cross-section 704 may be A-A' in the first cross-section 702.

[0150] As shown in Figure 7, in this embodiment, groove-shaped recesses 772, 774, and 776, and recess-shaped recess 778 are formed on the first surface 442 of the positive electrode active material layer 224. In this embodiment, the positive electrode current collector 222 and the positive electrode active material layer 224 are arranged so that the first surface 422 of the positive electrode current collector 222 and the first surface 442 of the positive electrode active material layer 224 are in contact. As a result, the recesses 772, 774, 776, and 778 extend from the side surface 446 of the positive electrode active material layer 224 toward the interior of the positive electrode active material layer 224.

[0151] In one embodiment, each of the recesses 772, 774, 776, and 778 may be a void. This allows each of the recesses 772, 774, 776, and 778 to function as an ion-permeable region. The ion-permeable regions facilitate the movement of electrolyte ions between the electrolyte 250, which is placed on or near the surface of the side surface 446, and the positive electrode active material, which is placed on the inner surface of each ion-permeable region.

[0152] In other embodiments, an ion-conducting material may be placed inside at least one of the recesses 772, 774, 776, and 778. This allows the ion-conducting material to function as an ion-permeable region. The ion-permeable region facilitates the movement of electrolyte ions between the electrolyte 250, which is placed on or near the surface of the side surface 446, and the positive electrode active material, which is placed on the inner surface of each ion-permeable region.

[0153] Figure 8 illustrates other features of the ion-permeable region formed in the positive electrode 220. Figure 8 schematically shows examples of the first cross-section 802 and the second cross-section 804 of the positive electrode 220. The first cross-section 802 may be an example of a cross-section of the positive electrode 220 when the positive electrode 220 is cut in a section substantially parallel to the stacking direction of the constituent members of the positive electrode 220 (the z direction in the figure). The first cross-section 802 may be B-B' in the second cross-section 804. The second cross-section 804 may be A-A' in the first cross-section 802.

[0154] As shown in Figure 8, in this embodiment, the first surface 422 of the positive electrode current collector 222 has groove-shaped recesses 872, 874, and 876, a recessed shape recess 878, and a hole-shaped recess 882. In this embodiment, the positive electrode current collector 222 and the positive electrode active material layer 224 are arranged so that the first surface 422 of the positive electrode current collector 222 and the first surface 442 of the positive electrode active material layer 224 are in contact.

[0155] As a result, recesses 872, 874, 876, and 878 extend from the side surface 426 of the positive electrode current collector 222 toward the interior of the positive electrode current collector 222. Recess 882 penetrates the positive electrode current collector 222. In addition, the upper ends of recesses 872, 874, 876, 878, and 882 in Figure 8 are in contact with the first surface 442 of the positive electrode active material layer 224.

[0156] In one embodiment, each of the recesses 872, 874, 876, 878, and 882 may be a void. This allows each of the recesses 872, 874, 876, 878, and 882 to function as an ion-permeable region. Each ion-permeable region corresponding to each of the recesses 872, 874, 876, and 878 facilitates the movement of electrolyte ions between the electrolyte 250, which is located on or near the surface of the side surface 446, and the positive electrode active material, which is located on the inner surface of each ion-permeable region. Each ion-permeable region corresponding to the recess 882 facilitates the movement of electrolyte ions between the electrolyte 250 or electrolyte 330, which is located on or near the surface of the first surface 424, and the positive electrode active material, which is located on the inner surface of each ion-permeable region.

[0157] In other embodiments, an ion-conducting material may be placed inside at least one of the recesses 872, 874, 876, 878, and 882. This allows the ion-conducting material to function as an ion-permeable region. Each ion-permeable region corresponding to recesses 872, 874, 876, and 878 facilitates the movement of electrolyte ions between the electrolyte 250, which is placed on or near the surface of side 446, and the positive electrode active material, which is placed on the inner surface of each ion-permeable region. Each ion-permeable region corresponding to recess 882 facilitates the movement of electrolyte ions between the electrolyte 250 or electrolyte 330, which is placed on or near the surface of the first surface 424, and the positive electrode active material, which is placed on the inner surface of each ion-permeable region.

[0158] Figure 9 schematically shows an example of a method for producing a positive electrode 220. In this embodiment, an example of a method for producing a secondary electrode is described, using the case in which a positive electrode 220 is produced in which an ion-conducting material that functions as an ion-permeable region is arranged inside the positive electrode active material layer 224.

[0159] According to this embodiment, first, in step 912 (the step may be referred to as S), a slurry containing the materials constituting the positive electrode active material layer 224 and an organic solvent is prepared. For example, a slurry containing a positive electrode active material, an ion-conducting material, and a solvent is prepared. At least one of a binder and a conductive additive may be further added to the slurry. Also, in S914, the slurry prepared in S912 is applied to the first surface 422 of the positive electrode current collector 222.

[0160] Next, in S916, the slurry is dried so that the positive electrode active material and the ion-conducting material undergo phase separation. Specifically, a portion of the solvent contained in the slurry is evaporated while suppressing the evaporation rate of the solvent until the ion-conducting material aggregates. Examples of methods for suppressing the evaporation rate of the solvent include controlling the temperature and / or pressure of the slurry. The degree of phase separation between the positive electrode active material and the ion-conducting material is determined, for example, by observing the surface and / or cross-section of the positive electrode using a scanning electron microscope (SEM). For example, the operating parameters for the slurry drying operation are determined based on the slurry temperature and / or pressure, the drying time, and the observation results from the SEM. By controlling the temperature and / or pressure of the slurry, the step of evaporating the solvent while suppressing the evaporation rate of the solvent can be terminated when the degree of phase separation between the positive electrode active material and the ion-conducting material meets a predetermined standard.

[0161] After sufficient phase separation has occurred between the positive electrode active material and the ion-conducting material, the slurry is completely dried in S918. This produces a positive electrode 220 in which an ion-permeable region is formed on at least a portion of the surface of the positive electrode active material layer 224.

[0162] [An example of an alternative embodiment] In this embodiment, an example of a method for producing a secondary electrode was described, using as an example a case in which a positive electrode 220 is produced in which an ion-conducting material that functions as an ion-permeable region is arranged inside the positive electrode active material layer 224. However, the method for producing a secondary electrode is not limited to this embodiment.

[0163] In another embodiment, a positive electrode 220 is produced in which holes, grooves, or depressions that function as ion-permeable regions are formed on the surface of the positive electrode active material layer 224. The holes may be through holes penetrating the positive electrode active material layer 224.

[0164] According to this embodiment, for example, first, a slurry containing the material constituting the positive electrode active material layer 224 and an organic solvent is prepared. For example, a slurry containing the positive electrode active material and a solvent is prepared. At least one of a binder and a conductive additive may be further added to the slurry. Next, the slurry prepared in S912 is applied to the first surface 422 of the positive electrode current collector 222. Next, holes, grooves, or depressions are formed in the slurry. After that, the slurry is dried. This produces the positive electrode 220. Note that holes, grooves, or depressions may be formed after the slurry has been dried. [Examples]

[0165] [Example 1] [Manufacturing of secondary batteries] (Fabrication of positive electrode active material) Lithium bis(trifluoromethanesulfonyl)imide (LiN(CF3SO2)2) was added to a glass container containing a 0.05 M sulfolane solution with dithiogizamide and stirred. Lithium bis(trifluoromethanesulfonyl)imide was added to make a total solution of 0.25 M. Two platinum electrodes were immersed in the above solution, and a constant voltage of 4.2 V was applied to the platinum electrodes for 24 hours while stirring the solution. A black solution was obtained from the above 24-hour reaction. The above black solution was filtered and dried to obtain a black powder.

[0166] Raman spectroscopy (Raman mapping) and infrared spectroscopy were performed on the black powder. The results of the Raman and infrared spectroscopy measurements confirmed that the product of the above reaction is 1,2,4,5-dithiadiazine-3,6-dicarbothioamide, represented by chemical formula (3). [Chemical formula (3)] [ka]

[0167] (Fabrication of the positive electrode) Next, a slurry was prepared by mixing 300 mg of the above-mentioned 1,2,4,5-dithiadiazine-3,6-dicarbothioamide as the positive electrode active material, 600 mg of graphite powder as a conductive additive, 100 mg of polytetrafluoroethylene as a binder, and 2 g of N-methyl-2-pyrrolidone as an organic solvent.

[0168] Next, an aluminum foil measuring 150 mm in width, 230 mm in length, and 15 μm in thickness was prepared as a current collector. Then, the slurry described above was applied to one side of the aluminum foil. After that, the aluminum foil coated with the slurry was dried at 80°C for 30 minutes. This formed an active material layer on the surface of the aluminum foil. The thickness of the active material layer after drying was 80 μm.

[0169] Subsequently, the aluminum foil with the active material layer formed on it was punched out into a 12 mm diameter circle, and holes were drilled at 10 μm intervals using a 2 μm diameter needle. This created 1.13 × 10¹⁶ holes that penetrated the active material layer in the thickness direction. 6 Numerous through-holes were formed. This allowed for the fabrication of a positive electrode with an active material layer having an ion-permeable region.

[0170] (Assembly of secondary batteries) Next, the positive electrode was impregnated with the electrolyte, allowing the electrolyte to seep into the voids within the positive electrode. The electrolyte used was a mixed solution containing equimolar amounts of methyltetraglyceride (organic solvent) and LiN(CF3SO2)2 (electrolyte salt).

[0171] Next, a 20 μm thick separator made of a porous polypropylene film impregnated with the above electrolyte was laminated on the positive electrode, a 0.2 mm thick lithium extruded plate punched to a diameter of 14 mm was placed on top of it, and a 16 mm diameter stainless steel current collector was further laminated. After that, a metal spring was placed on the current collector, and the negative electrode case was joined to the positive electrode case with a gasket placed around the periphery, and the outer casing was sealed with a crimping machine to fabricate a sealed coin-type secondary battery having 1,2,4,5-dithiadiazine-3,6-dicarbothioamide as the positive electrode active material and metallic lithium as the negative electrode active material.

[0172] In this embodiment, the positive electrode and separator were immersed in the electrolyte and used while still wet. Therefore, the filling of the internal space of the coin-type secondary battery with electrolyte was omitted.

[0173] [Checking the operation of the rechargeable battery] The coin-type secondary battery prepared as described above was charged using a charge / discharge tester (TOSCAT3100, manufactured by Toyo Systems Co., Ltd.) with a constant current of 0.1 mA until the voltage reached 4.2 V, and then discharged with a constant current of 0.1 mA until the voltage reached 1.5 V. As a result, it was confirmed that this battery is a secondary battery with a discharge capacity of 2.1 mAh and a voltage flat region at a charge / discharge voltage of 2.1 V. The capacity density per unit mass of the positive electrode active material calculated from the above discharge capacity was 500 Ah / kg.

[0174] Furthermore, the above-mentioned charge / discharge tester was used to repeat the charge / discharge cycle 100 times within the range of 1.5 to 4.2 [V]. As a result, the discharge capacity after 100 cycles was 1.8 [mAh] (97% of the initial capacity), indicating excellent stability.

[0175] [Comparative Example 1] [Manufacturing of secondary batteries] 1,2,4,5-Dithiadiazine-3,6-Dicarbothioamide was prepared using the same procedure as in Example 1. 300 mg of 1,2,4,5-Dithiadiazine-3,6-Dicarbothioamide as the positive electrode active material, 600 mg of graphite powder as a conductive additive, and 100 mg of polytetrafluoroethylene as a binder were mixed and kneaded, then pressure-molded to obtain a sheet-like material with a thickness of approximately 150 μm. Next, this sheet-like material was dried in a vacuum at 70°C for 1 hour, and then punched out into a circle with a diameter of 12 mm to produce the positive electrode. Furthermore, using the above positive electrode, a sealed coin-type secondary battery was prepared using the same procedure as in Example 1, with 1,2,4,5-Dithiadiazine-3,6-Dicarbothioamide as the positive electrode active material and metallic lithium as the negative electrode active material.

[0176] [Checking the operation of the rechargeable battery] The coin-type secondary battery prepared as described above was charged using a charge / discharge tester (TOSCAT3100, manufactured by Toyo Systems Co., Ltd.) with a constant current of 0.1 mA until the voltage reached 4.2 V, and then discharged with a constant current of 0.1 mA until the voltage reached 1.5 V. As a result, it was confirmed that this battery is a secondary battery with a discharge capacity of 2.7 mAh and a voltage flat region at a charge / discharge voltage of 2.1 V. The capacity density per unit mass of the positive electrode active material calculated from the above discharge capacity was 350 [Ah / kg].

[0177] Subsequently, the above-mentioned charge / discharge tester was used to repeat the charge / discharge cycle 100 times within the range of 1.5 to 4.2V. As a result, the discharge capacity after 100 cycles was 2.3mAh (85% of the initial capacity).

[0178] [Example 2] [Manufacturing of secondary batteries] (Fabrication of positive electrode active material) Lithium hexafluorophosphate was added to a glass container containing a 0.01 M ethanol solution of dithioxamide and stirred. Lithium hexafluorophosphate was added to make a total solution of 0.25 M. Two platinum electrodes were immersed in the above solution, and a constant voltage of 4.2 V was applied to the platinum electrodes for 48 hours while stirring the solution. A black solution was obtained after the above 48 hours of reaction. The above black solution was filtered and dried to obtain a black powder.

[0179] Raman spectroscopy (Raman mapping) and infrared spectroscopy were performed on the black powder. The results of the Raman and infrared spectroscopy measurements confirmed that the main product of the above reaction is [3,3'-bis-1,2,4,5-dithiadiazine]-6,6'-dicarbothioamide, represented by chemical formula (4). [Chemical formula (4)] [ka]

[0180] (Fabrication of the positive electrode and assembly of the secondary battery) A coin-type battery was fabricated in the same manner as in Example 1, except that [3,3'-bis-1,2,4,5-dithiadiazine-3,6-dicarbothioamide]-6,6'-dicarbothioamide was used as the positive electrode active material instead of 1,2,4,5-dithiadiazine-3,6-dicarbothioamide in Example 1.

[0181] [Checking the operation of the rechargeable battery] Using the same charge / discharge tester as in Example 1, the coin-type secondary battery was charged with a constant current of 0.1 [mA] until the voltage reached 4.2 [V], and then discharged with a constant current of 0.1 [mA] to 1.5 [V]. As a result, it was confirmed that this battery is a secondary battery with a discharge capacity of 1.8 [mAh] and a voltage flat region at a charge / discharge voltage of 2.1 [V]. The capacity density per unit mass of the positive electrode active material calculated from the above discharge capacity was 450 [Ah / kg].

[0182] Furthermore, the above-mentioned charge / discharge tester was used to repeat the charge / discharge cycle 100 times within the range of 1.5 to 4.2 [V]. As a result, the discharge capacity after 100 cycles was 1.6 [mAh] (89% of the initial capacity), indicating excellent stability.

[0183] [Comparative Example 2] [Manufacturing of secondary batteries] A coin-type battery was fabricated in the same manner as in Comparative Example 1, except that [3,3'-bis-1,2,4,5-dithiadiazine-3,6-dicarbothioamide]-6,6'-dicarbothioamide was used as the positive electrode active material instead of 1,2,4,5-dithiadiazine-3,6-dicarbothioamide in Comparative Example 1.

[0184] [Checking the operation of the rechargeable battery] Using the same charge / discharge tester as in Example 1, the coin-type secondary battery was charged with a constant current of 0.1 [mA] until the voltage reached 4.2 [V], and then discharged with a constant current of 0.1 [mA] to 1.5 [V]. As a result, it was confirmed that this battery is a secondary battery with a discharge capacity of 2.25 [mAh] and a voltage flat region at a charge / discharge voltage of 2.1 [V]. The capacity density per unit mass of the positive electrode active material calculated from the above discharge capacity was 300 [Ah / kg].

[0185] Furthermore, the above-mentioned charge / discharge tester was used to repeat the charge / discharge cycle 100 times within the range of 1.5 to 4.2 [V]. As a result, the discharge capacity after 100 cycles was 1.58 [mAh] (70% of the initial capacity).

[0186] Comparing the secondary battery of Example 1 with the secondary battery of Comparative Example 1, the capacity density per unit mass of the positive electrode active material in the secondary battery of Example 1 is greater than that of the secondary battery of Comparative Example 1. Similarly, comparing the secondary battery of Example 2 with the secondary battery of Comparative Example 2, the capacity density per unit mass of the positive electrode active material in the secondary battery of Example 2 is greater than that of the secondary battery of Comparative Example 2. This is thought to be because the through-holes formed in the active material layer of the positive electrode functioned as ion-permeable regions, allowing the positive electrode active material disposed within the active material layer to be effectively utilized.

[0187] Furthermore, a person skilled in the art who has read the description in this specification will understand that when an ion-conducting material is placed inside the active material layer, and a portion of the ion-conducting material is placed on the surface of the active material layer, the ion-conducting material functions as an ion-permeable region, similar to the through-holes in Examples 1 and 2. Therefore, a person skilled in the art who has read the descriptions in Examples 1 and 2, and Comparative Examples 1 and 2, will understand that a positive electrode utilizing the aforementioned ion-conducting material as an ion-permeable region also has a large capacity density.

[0188] Furthermore, a person skilled in the art will understand that by separating the active material and the ion-conducting material in the process of drying a slurry containing the active material and the ion-conducting material, an ion-permeable region having the same function as the through-holes in Examples 1 and 2 can be formed using the ion-conducting material. As a result, a person skilled in the art who has read the description of this specification can produce a positive electrode using the aforementioned ion-conducting material as an ion-permeable region.

[0189] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It will be clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.

[0190] It should be noted that the execution order of operations, procedures, steps, and stages in the apparatus, systems, programs, and methods described in the claims, specifications, and drawings is not explicitly stated as "before" or "prior to," and that these can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," and "next," for convenience, this does not mean that it is essential to perform the operations in that order. [Explanation of Symbols]

[0191] 100 Aircraft body, 110 Battery, 112 Energy cell, 120 Power control circuit, 130 Electric motor, 140 Propeller, 150 Sensor, 160 Control device, 212 Positive electrode case, 214 Negative electrode case, 216 Sealant, 218 Metal spring, 220 Positive electrode, 222 Positive electrode current collector, 224 Positive electrode active material layer, 230 Separator, 240 Negative electrode, 242 Negative electrode current collector, 244 Negative electrode active material layer, 250 Electrolyte, 330 Electrolyte, 422 First surface, 424 Second surface, 426 Side, 442 First surface, 444 Second surface, 446 Side, 460 Ion permeable region, 462 Ion permeable region, 464 Ion permeable region, 562 Ion permeable region, 572 Ion permeable region, 574 Ion permeable region, 582 Ion permeable region, 584 Ion permeable region, 640 Particle, 660 Void, 702 First cross section, 704 Second cross section, 772 Recess, 774 Recess, 776 Recess, 778 Recess, 802 First cross section, 804 Second cross section, 872 Recess, 874 Recess, 876 Recess, 878 Recess, 882 Recess

Claims

1. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. Electrodes for secondary batteries.

2. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

3. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region includes a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

4. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes at least one of a recess extending inward from the surface of the current collector or the active material layer, or a through hole penetrating the current collector or the active material layer. Electrodes for secondary batteries.

5. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes at least one of a recess extending inward from the surface of the current collector or the active material layer, or a through hole penetrating the current collector or the active material layer. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

6. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes at least one of a recess extending inward from the surface of the current collector or the active material layer, or a through hole penetrating the current collector or the active material layer. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region includes a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

7. The ion-permeable region is positioned so as to be able to contact the electrolyte of the secondary battery and the surface of the active material when the secondary battery electrode is incorporated into the secondary battery. An electrode for a secondary battery according to any one of claims 1 to 6.

8. The current collector and the active material layer are arranged such that the first surface of the current collector and the first surface of the active material layer are in contact with each other. The void in the ion permeable region is (i) A recess formed on the first surface of the current collector and extending from the side surface of the current collector toward the interior of the current collector, (ii) Through holes that penetrate the current collector, (iii) A recess disposed on the first surface of the active material layer and extending from the side surface of the active material layer toward the interior of the active material layer, Further including at least one of the An electrode for a secondary battery according to any one of claims 4 to 6.

9. The current collector and the active material layer are arranged such that the first surface of the current collector and the first surface of the active material layer are in contact with each other. The void in the ion-permeable region includes a second surface located on the opposite side of the first surface of the active material layer, or a recess formed on the side surface of the active material layer. An electrode for a secondary battery according to any one of claims 4 to 6.

10. The recess has a hole shape, a groove shape, a depression shape, and a combination thereof. The electrode for a secondary battery according to claim 8 or claim 9.

11. A secondary battery electrode used as the positive or negative electrode of a secondary battery having a solid or gel-like electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The void in the ion-permeable region containing the ion-conducting material inside includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. Electrodes for secondary batteries.

12. A secondary battery electrode used as the positive or negative electrode of a secondary battery having a solid or gel-like electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The void in the ion-permeable region containing the ion-conducting material inside includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

13. A secondary battery electrode used as the positive or negative electrode of a secondary battery having a solid or gel-like electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The void in the ion-permeable region containing the ion-conducting material inside includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region includes a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

14. A secondary battery electrode used as the positive or negative electrode of a secondary battery having a solid or gel-like electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The void in the ion-permeable region containing the ion-conducting material includes at least one of a recess extending inward from the surface of the current collector or the active material layer, or a through hole penetrating the current collector or the active material layer. Electrodes for secondary batteries.

15. A secondary battery electrode used as the positive or negative electrode of a secondary battery having a solid or gel-like electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The void in the ion-permeable region containing the ion-conducting material includes at least one of a recess extending inward from the surface of the current collector or the active material layer, or a through hole penetrating the current collector or the active material layer. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

16. A secondary battery electrode used as the positive or negative electrode of a secondary battery having a solid or gel-like electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having an ion-conducting material with a greater ion transport rate than the active material. The void in the ion-permeable region containing the ion-conducting material includes at least one of a recess extending inward from the surface of the current collector or the active material layer, or a through hole penetrating the current collector or the active material layer. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region includes a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. Electrodes for secondary batteries.

17. The ion-permeable region is positioned so as to be able to contact the electrolyte of the secondary battery and the surface of the active material when the secondary battery electrode is incorporated into the secondary battery. An electrode for a secondary battery according to any one of claims 11 to 16.

18. The active material comprises a crystalline or amorphous organic compound or a salt thereof (excluding polymethine imine), An electrode for a secondary battery according to any one of claims 1 to 17.

19. The active material is a compound having a dithiadiazine group or a salt thereof. The electrode for a secondary battery according to claim 18.

20. The compound having the dithiadiazine group includes the compound represented by the following general formula (1) or a derivative thereof. The electrode for a secondary battery according to claim 19. [General formula (1)] 【Chemistry 1】 [In general formula (1), R １ and R ２ Each of these independently represents either a hydrogen atom or an organic group. Furthermore, the degree of polymerization n is a positive integer greater than or equal to 1.

21. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the active material layer. An electrode for a secondary battery according to any one of claims 4 to 6 or 11 to 17.

22. The active material layer has a plurality of particles comprising the active material and a binder, The void in the ion permeable region is Formed between the plurality of particles, Extending from the surface of the active material layer toward the interior of the active material layer, An electrode for a secondary battery according to any one of claims 4 to 6 or 11 to 17.

23. The ion-conducting material in the ion-permeable region includes at least one of a polymer gel electrolyte, a polymer electrolyte, and a solid electrolyte. An electrode for a secondary battery according to any one of claims 1 to 22.

24. The volume of the ion-permeable region is 50% or less of the volume of the active material layer, including the volume of the ion-permeable region disposed within the active material layer. An electrode for a secondary battery according to any one of claims 1 to 23.

25. The mass of the ion-conducting material contained in the ion-permeable region is 50% or less of the mass of the active material layer, including the mass of the ion-permeable region disposed in the active material layer. An electrode for a secondary battery according to any one of claims 1 to 24.

26. The thickness of the active material layer is 80 μm or more. An electrode for a secondary battery according to any one of claims 1 to 25.

27. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The active material layer has a plurality of particles comprising the active material and a binder, The void in the ion permeable region is Formed between the plurality of particles, Extending from the surface of the active material layer toward the interior of the active material layer, Electrodes for secondary batteries.

28. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. The active material layer has a plurality of particles comprising the active material and a binder, The void in the ion permeable region is Formed between the plurality of particles, Extending from the surface of the active material layer toward the interior of the active material layer, Electrodes for secondary batteries.

29. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region comprises a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. The active material layer has a plurality of particles comprising the active material and a binder, The void in the ion permeable region is Formed between the plurality of particles, Extending from the surface of the active material layer toward the interior of the active material layer, Electrodes for secondary batteries.

30. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The volume of the ion-permeable region is 10% or less of the volume of the active material layer, including the volume of the ion-permeable region disposed within the active material layer. Electrodes for secondary batteries.

31. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. The volume of the ion-permeable region is 10% or less of the volume of the active material layer, including the volume of the ion-permeable region disposed within the active material layer. Electrodes for secondary batteries.

32. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region comprises a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. The volume of the ion-permeable region is 10% or less of the volume of the active material layer, including the volume of the ion-permeable region disposed within the active material layer. Electrodes for secondary batteries.

33. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, An active material layer comprising an active material containing a crystalline or amorphous organic compound or a salt thereof, which is in contact with at least a portion of the current collector, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The thickness of the active material layer is 80 μm or more. Electrodes for secondary batteries.

34. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The ion-conducting material in the ion-permeable region comprises a mixture or reaction product of the active material and at least one of a nonionic surfactant and a stable radical compound. The thickness of the active material layer is 80 μm or more. Electrodes for secondary batteries.

35. A secondary battery electrode used as the positive or negative electrode of a secondary battery equipped with an electrolyte, A current collector containing a conductive material, In contact with at least a portion of the current collector, an active material layer containing an active material, Equipped with, The current collector and the active material layer, or the active material layer, are provided with an ion-permeable region having at least one of a void into which electrolyte ions of the electrolyte can enter, and an ion-conducting material having a greater ion transport rate than the active material. The void in the ion-permeable region includes a pore with a diameter of 1 μm or more formed on the surface of the current collector or the active material layer. The active material layer comprises the active material and a binder. The ion-conducting material in the ion-permeable region comprises a reaction product of the binder and at least one of a nonionic surfactant and a stable radical compound. The thickness of the active material layer is 80 μm or more. Electrodes for secondary batteries.

36. An electrode for a secondary battery according to any one of claims 1 to 35, An electrolyte solution or a solid or gel-like electrolyte, A secondary battery equipped with these features.

37. The secondary battery according to claim 36, A propulsion force generating device that generates propulsion force using electrical energy stored in the secondary battery, An aircraft equipped with [the following features].

38. A method for producing electrodes for secondary batteries, including a current collector and an active material layer, A step of preparing a slurry containing an active material comprising a crystalline or amorphous organic compound or a salt thereof, an ion-conducting material having a greater ion transport rate than the active material, and a solvent, The steps include applying the slurry to the surface of the current collector, The steps include controlling the evaporation rate of the solvent to dry the slurry so that the active material and the ion-conducting material undergo phase separation, A method for producing electrodes for secondary batteries, having the following characteristics.

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