Dispersion processing system and dispersion processing method

Abstract

A dispersion processing system 1 comprises a dispersion device 2 and a dispersion evaluation assistance device 100. The dispersion evaluation assistance device 100 comprises: piping 102 through which a solid-liquid mixture having been subjected to dispersion processing flows; a first electrode and a second electrode disposed in the piping 102 so that an AC voltage can be applied to or an AC current can be superimposed on the solid-liquid mixture in the piping 102; a power supply unit 106 that, between a pair of the electrodes, applies the AC voltage or superimposes the AC current; a measurement unit 108 that measures a current generated between the pair of electrodes due to the application of the AC voltage or measures a voltage generated between the pair of electrodes due to the superimposition of the AC current; and a calculation unit 110 that calculates, by using a measurement result of the measurement unit 108, the resistance of the solid-liquid mixture serving as an index of the degree of dispersion of a conductive solid in the solid-liquid mixture.

Description

Distributed processing system and distributed processing method

[0001] The present disclosure relates to a distributed processing system and a distributed processing method.

[0002] Conventionally, electric storage devices such as lithium ion batteries, lithium ion secondary batteries, alkaline dry batteries, electric double layer capacitors, and electrochemical capacitors have been known. These electric storage devices have used electrode slurries. Electrode slurries are solid-liquid mixtures having electronic conductivity, in which conductive solids such as electrode active materials and conductive additives are dispersed in a solvent such as water (see, for example, Patent Document 1).

[0003] International Publication No. 2014 / 142045

[0004] In the production of solid-liquid mixtures such as electrode slurries, there is a demand for grasping the degree of dispersion of a conductive solid in a solvent when dispersing the conductive solid in the solid-liquid mixture in order to ensure the quality of the solid-liquid mixture.

[0005] The present disclosure has been made in view of the above circumstances, and its purpose is to provide a technique for supporting evaluation of the degree of dispersion of a conductive solid in a dispersion treatment of the conductive solid.

[0006] One aspect of the present disclosure is a dispersion processing system. The system includes a dispersing device that performs a dispersion process on a solid-liquid mixture containing a solvent and a conductive solid to disperse the conductive solid, and a dispersion evaluation support device that supports evaluation of the degree of dispersion of the conductive solid in the solid-liquid mixture. The dispersion evaluation support device includes a pipe through which the dispersed solid-liquid mixture flows, first and second electrodes disposed within the pipe, the first and second electrodes being capable of applying an AC voltage or superimposing an AC current on the solid-liquid mixture in a space extending between a first position in the pipe and a second position offset from the first position in the extension direction of the pipe, a power supply unit that applies an AC voltage or superimposes an AC current between the first and second electrodes, a measurement unit that measures a current generated between the first and second electrodes by applying the AC voltage or a voltage generated between the first and second electrodes by superimposing the AC current, and a calculation unit that uses the measurement results from the measurement unit to calculate the resistance of the solid-liquid mixture, which serves as an indicator of the degree of dispersion of the conductive solid in the solid-liquid mixture.

[0007] Another aspect of the present disclosure is a dispersion treatment method, which includes: subjecting a solid-liquid mixture containing a solvent and a conductive solid to a dispersion treatment of the conductive solid; flowing the dispersed solid-liquid mixture through a pipe; applying an AC voltage or superimposing an AC current to the solid-liquid mixture in a space extending between a first position in the pipe and a second position shifted from the first position in the extension direction of the pipe; measuring the current generated by the application of the AC voltage or measuring the voltage generated by the superimposition of the AC current; and using the measurement results to calculate the resistance of the solid-liquid mixture, which is an index of the degree of dispersion of the conductive solid in the solid-liquid mixture.

[0008] Any combination of the above components, and conversion of the expression of the present disclosure into a method, device, system, etc., are also valid aspects of the present disclosure.

[0009] According to the present disclosure, it is possible to assist in evaluating the degree of dispersion of a conductive solid during dispersion treatment of the conductive solid.

[0010] 4A is a schematic diagram of a distributed processing system according to the first embodiment; FIG. 4B is a schematic diagram of an electrode unit; FIG. 4C is a diagram for explaining a method for setting a frequency to be used; FIG. 4D is a diagram showing the transition of the resistance of a solid-liquid mixture; FIG. 4E is a diagram showing the transition of the resistance of a solid-liquid mixture; Ｂ 4(C) is an enlarged view of the dashed line region R in FIG. Ｃ 4(D) is a diagram showing the standard deviation of the resistance in the dashed line region R in FIG. Ｄ 4(E) is a diagram showing the standard deviation of the resistance in the dashed line region R in FIG. Ｅ 4(F) is a diagram showing the standard deviation of the resistance in the dashed line region R in FIG. Ｆ 10 is a diagram showing the standard deviation of resistance in a distributed processing system according to a second embodiment of the present invention;

[0011] The present disclosure will be described below with reference to the drawings based on preferred embodiments. The embodiments are illustrative and do not limit the present disclosure, and all features and combinations thereof described in the embodiments are not necessarily essential to the present disclosure. The same or equivalent components, parts, and processes shown in each drawing are designated by the same reference numerals, and redundant descriptions will be omitted where appropriate. The scale and shape of each part shown in each drawing are set for convenience to facilitate explanation and should not be interpreted as limiting unless otherwise specified. Furthermore, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, these terms do not represent any order or importance, but are intended to distinguish one configuration from another. Furthermore, some components that are not important for explaining the embodiments are omitted from each drawing.

[0012] (First Embodiment) Fig. 1 is a schematic diagram of a distributed processing system 1 according to a first embodiment. In Fig. 1, some of the components of each device are depicted as functional blocks. These functional blocks are realized as a hardware configuration by elements and circuits such as a computer CPU and memory, and as a software configuration by a computer program or the like. Those skilled in the art will understand that these functional blocks can be realized in various ways by combining hardware and software.

[0013] The distributed processing system 1 includes a distribution device 2 , a valve 4 , a pump 6 , a feed pipe 8 , a return pipe 10 , a supply pipe 12 , a tank 14 , and a distribution evaluation support device 100 .

[0014] The dispersion device 2 subjects a solid-liquid mixture containing a solvent and a conductive solid to a dispersion treatment of the conductive solid. The dispersion device 2 can be configured with a known kneader, stirring tank, or the like. In this embodiment, the solid-liquid mixture is, for example, an electrode slurry. The electrode slurry is applied to a current collector and dried to obtain an electrode plate. The electrode slurry contains at least one of an electrode active material and a conductive additive as the conductive solid. In the case of a slurry for a positive electrode used in a typical lithium-ion secondary battery, an organic solvent such as N-methyl-2-pyrrolidone is exemplified as the solvent, lithium cobalt oxide or lithium iron phosphate is exemplified as the electrode active material, and graphite is exemplified as the conductive additive. In the case of a slurry for a negative electrode used in a typical lithium-ion secondary battery, water is exemplified as the solvent, and graphite is exemplified as the electrode active material and the conductive additive. Note that the solid-liquid mixture does not have to be an electrode slurry.

[0015] A valve 4 is connected to the dispersing device 2 via a feed pipe 8 and a return pipe 10. A tank 14 is connected to the valve 4 via a supply pipe 12. A pump 6 is provided midway through the feed pipe 8, and the solid-liquid mixture is sent from the dispersing device 2 to the valve 4 via the feed pipe 8 by driving the pump 6. The valve 4 supplies the solid-liquid mixture sent from the dispersing device 2 to the tank 14 via the feed pipe 12. Alternatively, the valve 4 returns the solid-liquid mixture sent from the dispersing device 2 to the dispersing device 2 via the return pipe 10. The tank 14 that stores the solid-liquid mixture is sent to the next process.

[0016] A distributed evaluation support device 100 is provided midway along the feed pipe 8. The distributed evaluation support device 100 includes a pipe 102, an electrode unit 104, a power supply unit 106, a measurement unit 108, a calculation unit 110, an evaluation unit 112, and a storage unit 120.

[0017] The pipe 102 is a flow path through which the solid-liquid mixture, which has been subjected to a dispersion process of the conductive solid by the dispersing device 2, flows. In this embodiment, the region of the feed pipe 8 between the dispersing device 2 and the pump 6 constitutes the pipe 102. That is, the dispersion evaluation support device 100 is provided in the feed pipe 8. The dispersion evaluation support device 100 may also be provided in the region of the feed pipe 8 between the pump 6 and the valve 4. The dispersion evaluation support device 100 may also be provided in the return pipe 10 or the like.

[0018] The electrode unit 104 includes a first electrode 114 and a second electrode 116. Hereinafter, the first electrode 114 and the second electrode 116 may be collectively referred to as a pair of electrodes as appropriate. FIG. 2 is a schematic diagram of the electrode unit 104. The pair of electrodes is disposed within the pipe 102. As an example, the electrode unit 104 has a rod-shaped body 118 inserted into the pipe 102 and disposed at a distance from the pipe 102. The first electrode 114 is provided on the pipe 102, and the second electrode 116 is provided on the rod-shaped body 118. The first electrode 114 and the second electrode 116 are insulated from each other. The first electrode 114 and the second electrode 116 are made of an electrically conductive material. The material has, for example, a volume resistivity of 0.1 Ω·cm or less. Specific examples of materials constituting the first electrode 114 and the second electrode 116 include insoluble metals such as stainless steel, titanium, platinum, gold, niobium, and ruthenium, as well as carbon. These materials can also be combined as appropriate.

[0019] The first electrode 114 is provided at least on the inner wall, i.e., the inner circumferential surface, of the pipe 102. The first electrode 114 may be provided on the entire inner wall of the pipe 102, or on a portion thereof. When the first electrode 114 is provided on a portion of the inner wall, it may be on a partial region in the direction of flow of the solid-liquid mixture, or on a partial region in the circumferential direction of the pipe 102. Furthermore, the entire pipe 102 may be made of an insoluble metal or the like, and the entire pipe 102 may constitute the first electrode 114. In other words, the first electrode 114 may be provided only on the surface of the inner wall of the pipe 102, or may extend into the interior of the inner wall.

[0020] The second electrode 116 is provided at least on the outer wall, i.e., the outer peripheral surface, of the rod-shaped body 118. The second electrode 116 may be provided on the entire outer wall of the rod-shaped body 118, or on a portion thereof. When the second electrode 116 is provided on a portion of the outer wall, it may be on a partial region in the direction of flow of the solid-liquid mixture, or on a partial region in the circumferential direction of the rod-shaped body 118. Furthermore, the entire rod-shaped body 118 may be made of an insoluble metal or the like, and the entire rod-shaped body 118 may constitute the second electrode 116. In other words, the second electrode 116 may be provided only on the surface of the outer wall of the rod-shaped body 118, or may extend into the interior of the outer wall.

[0021] The first electrode 114 and the second electrode 116 are arranged so that an AC voltage can be applied to the solid-liquid mixture in the space extending between an arbitrary first position 102a of the pipe 102 and a second position 102b shifted from the first position 102a in the extension direction of the pipe 102, or so that an AC current can be superimposed thereon. As an example, the first electrode 114 and the second electrode 116 are elongated and extend in the extension direction of the pipe 102. Therefore, the pair of electrodes extend parallel to the axis of the pipe 102, spaced apart in the radial direction of the pipe 102. Preferably, the pair of electrodes are arranged so that the distance between the pair of electrodes is equal at any position in the extension direction of the pipe 102.

[0022] This allows an AC voltage to be applied or an AC current to be superimposed on the solid-liquid mixture that spreads between the first position 102a and the second position 102b in the extension direction of the pipe 102, in other words, in the flow direction of the solid-liquid mixture. This improves the efficiency of evaluating the degree of dispersion of the conductive solid in the solid-liquid mixture. Hereinafter, the "degree of dispersion of the conductive solid in the solid-liquid mixture" will be referred to simply as the "degree of dispersion" as appropriate. The distance between the first position 102a and the second position 102b, in other words, the length of the first electrode 114 and the second electrode 116 in the extension direction of the pipe 102, is, for example, equal to or greater than the distance between the pair of electrodes and, for example, equal to or greater than the diameter of the pipe 102.

[0023] Furthermore, rod-shaped body 118 is positioned so that the distance from the inner wall of pipe 102 is substantially equal at each position in the extension direction of pipe 102. In other words, rod-shaped body 118 has a uniform thickness at least from first position 102a to second position 102b, and extends parallel to the axis of pipe 102. This makes it possible to make the distance between the pair of electrodes in the extension direction of pipe 102, i.e., the distance between first electrode 114 and second electrode 116 in the radial direction of pipe 102, substantially equal. As a result, the accuracy of evaluation of the degree of dispersion by dispersion evaluation support device 100 can be improved.

[0024] Furthermore, the rod-shaped body 118 is arranged so that the distance from the inner wall of the pipe 102 is substantially equal at each position in the circumferential direction of the rod-shaped body 118. In other words, the pipe 102 and the rod-shaped body 118 are arranged coaxially. This makes it possible to make the distance between the pair of electrodes substantially equal in the circumferential direction of the rod-shaped body 118. As a result, the accuracy of the evaluation of the degree of dispersion by the dispersion evaluation support device 100 can be improved. In other words, the rod-shaped body 118 constituting the second electrode 116 is inserted through the center of the pipe 102, so that it extends without deviation in the radial direction of the pipe 102 and without inclination parallel to the axis of the pipe 102.

[0025] In the example shown in FIG. 2 , the rod-shaped body 118 is solid. However, the rod-shaped body 118 is not limited to a solid body. For example, the rod-shaped body 118 may be hollow. In this case, the interior of the rod-shaped body 118 is sealed, and the solid-liquid mixture does not flow. By using a solid or hollow rod-shaped body 118, it is possible to prevent the rod-shaped body 118 from increasing the pressure loss caused by the rod-shaped body 118 when the solid-liquid mixture passes through the pipe 102. The rod-shaped body 118 may also be a cylindrical mesh. In this case, the solid-liquid mixture can move between the inside and outside of the rod-shaped body 118 through openings in the mesh while flowing through the pipe 102. Using a cylindrical mesh rod-shaped body 118 increases the contact area between the second electrode 116 and the solid-liquid mixture, thereby improving the accuracy of the evaluation of the degree of dispersion by the dispersion evaluation support device 100.

[0026] Furthermore, each of the pair of electrodes may be filter-shaped and extend in a direction intersecting the extension direction of the pipe 102, for example, in the radial direction of the pipe 102. For example, the first electrode 114 extends in the radial direction of the pipe 102 at the first position 102a. The second electrode 116 extends in the radial direction of the pipe 102 at the second position 102b. The filter-shaped first electrode 114 and second electrode 116 are fixed to the pipe 102, for example. If the pipe 102 is made of metal, insulation is provided between each electrode and the pipe 102. If the pipe 102 is made of non-metal, insulation between each electrode and the pipe 102 can be omitted, and the electrodes may be in direct contact with each other. The first electrode 114 and second electrode 116 are formed, for example, of a mesh sheet, a slit sheet, or a porous sheet. The solid-liquid mixture flowing through the pipe 102 can pass through the mesh of each electrode and proceed downstream of each electrode. By making each electrode filter-like, the contact area between each electrode and the solid-liquid mixture can be increased, and the accuracy of the evaluation of the degree of dispersion by the dispersion evaluation support device 100 can be improved.

[0027] The power supply unit 106 applies an AC voltage or superimposes an AC current between the first electrode 114 and the second electrode 116. The power supply unit 106 can be configured with a known AC / DC converter, inverter, control circuit, etc. For example, the first electrode 114 is connected to the negative output terminal of the power supply unit 106, and the second electrode 116 is connected to the positive output terminal of the power supply unit 106. Therefore, the first electrode 114 is the negative electrode and the second electrode 116 is the positive electrode. Alternatively, the first electrode 114 may be the positive electrode and the second electrode 116 may be the negative electrode. The control circuit can be configured with, for example, a microcomputer, and can control each switching element of the power supply unit 106 so that the current or voltage maintains a target value according to the measurement result of the measurement unit 108.

[0028] As an example, the power supply unit 106 applies an AC voltage, the frequency of which is fixed at a predetermined operating frequency, between the pair of electrodes. Alternatively, the power supply unit 106 superimposes an AC current, the frequency of which is fixed at a predetermined operating frequency, between the pair of electrodes. The operating frequency is set in advance and stored in the memory unit 120. Note that the memory unit 120 also stores information such as a reference frequency A and a threshold value, which will be described below, as needed. FIG. 3 is a diagram for explaining a method for setting the operating frequency. In this embodiment, the operating frequency is determined based on the resistance of the solid-liquid mixture measured by the AC impedance method or the resistance of a standard solution measured by the AC impedance method.

[0029] The standard solution has a predetermined degree of dispersion of the conductive solid. As an example, the standard solution has the same composition as the solid-liquid mixture as the liquid to be evaluated, and the degree of dispersion is the degree of dispersion required for an electrode slurry. In other words, the standard solution differs from the solid-liquid mixture as the liquid to be evaluated only in that the degree of dispersion clearly meets the acceptance criteria. The acceptance criteria for the degree of dispersion can be set appropriately based on the designer's empirical knowledge or experiments or simulations by the designer.

[0030] Specifically, according to the AC impedance method, an AC voltage or an AC current is applied to a solid-liquid mixture or a standard solution while changing the frequency, and the resistance is measured. This results in the graph shown in Figure 3. In Figure 3, the horizontal axis represents the real resistance, and the vertical axis represents the imaginary resistance. The frequency decreases from left to right in Figure 3. The dashed line represents the resistance of the standard solution. The solid line represents the resistance of a solid-liquid mixture when the degree of dispersion does not meet the acceptance criteria. Regardless of the degree of dispersion, the resistance graph is arc-shaped on the high-frequency side and linear on the low-frequency side. Furthermore, as the frequency is gradually decreased, the graph switches from an arc to a linear curve at a certain frequency, which serves as an inflection point. When the degree of dispersion does not meet the acceptance criteria, the graph shifts almost entirely in the direction of increasing resistance compared to when the acceptance criteria are met.

[0031] In the obtained graph, the frequency of the inflection point is determined as the reference frequency A. Then, A×10 －１Any frequency within the range of 10 to 10 is determined as the frequency to be used. As shown in FIG. 3, if the dispersion degree does not satisfy the pass standard, the reference frequency A shifts to the high resistance side and becomes the reference frequency A'. In contrast, if the dispersion degree of A x 10 －１ By setting the operating frequency to a range of 100 Hz to 100 kHz, it becomes possible to more reliably detect changes in resistance corresponding to changes in the degree of dispersion. When the solid-liquid mixture is an electrode slurry, the operating frequency is, for example, in the range of 100 Hz to 100 kHz.

[0032] When a standard solution is used in resistance measurement by the AC impedance method, the frequency of the inflection point detected in a single resistance measurement can be set as the reference frequency A. When a solid-liquid mixture is used in the resistance measurement, preferably, multiple inflection points are detected by multiple resistance measurements, and the average value of the frequencies of the inflection points is set as the reference frequency A. In a solid-liquid mixture, the degree of dispersion may locally satisfy the pass criterion. By performing multiple resistance measurements, the number of inflection points detected at the timing when a portion whose degree of dispersion satisfies the pass criterion passes between a pair of electrodes can be increased. This allows the reference frequency A obtained using a solid-liquid mixture to approach the reference frequency A obtained using a standard solution.

[0033] When a standard liquid is used to set the operating frequency, the setting process is easy and an accurate operating frequency can be set. On the other hand, when a solid-liquid mixture is used in the setting process, the preparation of a standard liquid is not required, thereby reducing the cost and effort required for the setting process. Furthermore, when the setting process is performed by the dispersion evaluation support device 100, the effort of replacing the standard liquid with a solid-liquid mixture can be omitted when transitioning from the setting process to the dispersion degree evaluation process.

[0034] Resistance measurement using the AC impedance method, acquisition of the reference frequency A, setting of the operating frequency, and input into the storage unit 120 are performed in advance as a preparation step before the dispersion degree evaluation process is performed by the dispersion evaluation support device 100. The preparation step may be performed using the dispersion evaluation support device 100 or another device. The operating frequency may be appropriately set within a range that can be realized by the power supply unit 106, for example, in the range of 100 Hz to 100 kHz, without relying on the AC impedance method. While the time required to evaluate the dispersion degree can be shortened by fixing the frequency, the frequency may also be changed stepwise or continuously. When a solid-liquid mixture contains multiple types of solid materials, there may be two or more inflection points, in other words, two or more reference frequencies A, depending on the number of types of solid materials. In this case, the operating frequency may be set for each inflection point, or the operating frequency may be set based on any one of the inflection points. When setting the operating frequency based on one inflection point, as an example, when the resistance calculation interval is relatively short, the operating frequency is set based on the inflection point on the high frequency side, and when the calculation interval is relatively long, the operating frequency is set based on the inflection point on the low frequency side.

[0035] Returning to FIG. 1 , the measurement unit 108 measures the current generated between the first electrode 114 and the second electrode 116 due to the application of an AC voltage. Alternatively, the measurement unit 108 measures the voltage generated between the first electrode 114 and the second electrode 116 due to the superposition of an AC current. When measuring the current generated between the pair of electrodes, the measurement unit 108 can be configured with a known ammeter, FRA (Frequency Response Analyzer), or the like electrically connected to the pair of electrodes. When measuring the voltage generated between the pair of electrodes, the measurement unit 108 can be configured with a known voltmeter, FRA, or the like electrically connected to the pair of electrodes.

[0036] The calculation unit 110 calculates the resistance of the solid-liquid mixture using the measurement results of the measurement unit 108. When the power supply unit 106 applies an AC voltage between the pair of electrodes, the measurement unit 108 measures the current generated between the pair of electrodes via the solid-liquid mixture. In this case, the calculation unit 110 can calculate the resistance component of the solid-liquid mixture from the value of this current and the value of the AC voltage applied between the pair of electrodes. The magnitude of the applied AC voltage can be selected appropriately depending on the electrode area, the distance between the electrodes, the type of solid-liquid mixture, etc., but is preferably 1 to 100 mV, and more preferably 5 to 50 mV. The application time of the AC voltage is not particularly limited. Note that a bias may be applied to the AC voltage.

[0037] Furthermore, when the power supply unit 106 superimposes an AC current between the pair of electrodes, the voltage generated between the pair of electrodes via the solid-liquid mixture is measured by the measurement unit 108. In this case, the calculation unit 110 can calculate the resistance component of the solid-liquid mixture from the value of this voltage and the value of the AC current superimposed between the pair of electrodes. The magnitude of the superimposed AC current can be selected appropriately depending on the electrode area, the distance between the electrodes, the type of solid-liquid mixture, etc., but is preferably 5 nA to 5 A, and more preferably 50 nA to 500 mA. The superimposition time of the AC current is not particularly limited. Note that a bias may be applied to the AC current.

[0038] FIG. 4(A) is a diagram showing the transition of the resistance of the solid-liquid mixture. As the solid-liquid mixture is subjected to a dispersion treatment by the dispersing device 2 and the degree of dispersion increases, the resistance of the solid-liquid mixture gradually decreases. Generally, the resistance of the solid-liquid mixture decreases significantly at the beginning of the dispersion treatment. As the time during which the solid-liquid mixture is subjected to the dispersion treatment increases, the decrease in the resistance of the solid-liquid mixture gradually subsides. In other words, as the time of the dispersion treatment increases, the amount of decrease in resistance per unit time in the solid-liquid mixture decreases. As such, since there is a correlation between the degree of dispersion and the resistance of the solid-liquid mixture, the resistance of the solid-liquid mixture serves as an index of the degree of dispersion. Therefore, the degree of dispersion can be evaluated by calculating the resistance of the solid-liquid mixture flowing through the pipe 102.

[0039] The calculation unit 110 of this embodiment calculates the standard deviation σ of the resistance from a plurality of resistors. Ｂ 4A is an enlarged view of the solid-liquid mixture. Macroscopically, the resistance of the solid-liquid mixture gradually decreases as shown in FIG. 4A, but microscopically, it tends to repeatedly increase and decrease as shown in FIG. 4B. Furthermore, the amplitude of the resistance attenuates as the time of the dispersion process increases. Therefore, the calculation unit 110 calculates the standard deviation σ of the resistance as an index of the degree of dispersion. That is, the calculation unit 110 first calculates multiple resistances of the solid-liquid mixture flowing through the pipe 102. Next, the calculation unit 110 calculates the average value of the multiple resistances, and then calculates the deviation of each resistance. Then, the standard deviation σ of the resistance is calculated from the multiple deviations.

[0040] FIG. 4C shows the broken line region R in FIG. Ｃ 4(D) is a diagram showing the standard deviation σ of the resistance in the dashed line region R in FIG. Ｄ 4(E) is a diagram showing the standard deviation σ of the resistance in the dashed line region R in FIG. Ｅ 4(F) is a diagram showing the standard deviation σ of the resistance in the dashed line region R in FIG. Ｆ 4(C) to 4(F) are diagrams showing the standard deviation σ of resistance in the solid-liquid mixture flowing through the pipe 102. In FIGS. 4(C) to 4(F), the horizontal axis represents the standard deviation σ, and the vertical axis represents the distribution density. As shown in FIGS. 4(C) to 4(F), the standard deviation σ decreases as the dispersion process time increases. As described above, there is a correlation between the degree of dispersion and the standard deviation σ of resistance, and therefore the standard deviation σ of resistance serves as an index of the degree of dispersion. Therefore, the degree of dispersion can be evaluated by calculating the standard deviation σ of the resistance of the solid-liquid mixture flowing through the pipe 102. Furthermore, when the standard deviation σ of resistance is used, the accuracy of the evaluation of the degree of dispersion can be improved compared to when the resistance value itself is used.

[0041] The calculation unit 110 may calculate the change in resistance per unit time from multiple resistances. The unit time is, for example, several seconds to several minutes. In other words, the change in resistance per unit time in this embodiment is a change over a time span on the order of seconds to minutes. As described above, the resistance of the solid-liquid mixture decreases less as the dispersion treatment time increases. Therefore, since there is a correlation between the degree of dispersion and the change in resistance per unit time, the change in resistance per unit time serves as an index of the degree of dispersion. The calculation unit 110 calculates the change in resistance from multiple resistances calculated sequentially and differentiates this change with respect to time to calculate the change in resistance per unit time.

[0042] Returning to FIG. 1 , the evaluation unit 112 evaluates the degree of dispersion of the conductive solid in the solid-liquid mixture according to the calculation results of the calculation unit 110. As an example, the evaluation unit 112 evaluates the degree of dispersion based on the progression of resistance change. When the calculation unit 110 calculates the standard deviation σ, the evaluation unit 112 evaluates that the solid-liquid mixture has the desired degree of dispersion, i.e., satisfies the pass criterion, for example, when the standard deviation σ falls below a predetermined threshold. Furthermore, when the calculation unit 110 calculates the change in resistance per unit time, the evaluation unit 112 evaluates that the solid-liquid mixture satisfies the pass criterion, for example, when the change per unit time falls below a predetermined threshold. The threshold is set in advance and stored in the storage unit 120. Furthermore, the threshold can be set appropriately based on the designer's empirical knowledge or experiments or simulations performed by the designer.

[0043] The evaluation unit 112 may evaluate the degree of dispersion as satisfying the pass criterion when the standard deviation σ of resistance or the amount of change per unit time remains below a threshold for a predetermined time, for example, several seconds to several minutes, which is longer than the above-mentioned unit time. The predetermined time can be set appropriately based on the designer's empirical knowledge or experiments or simulations performed by the designer. The dispersion evaluation support device 100 including the evaluation unit 112 allows the user to more quickly grasp the degree of dispersion.

[0044] Alternatively, the calculation unit 110 may calculate the amount of change in the standard deviation σ per unit time, and the evaluation unit 112 may evaluate the degree of dispersion based on the amount of change. Alternatively, the evaluation unit 112 may evaluate the degree of dispersion based on the difference between the standard deviation σ calculated at the nth time and the standard deviation σ calculated at the (n-1)th time or earlier, or the difference between the resistance calculated at the nth time and the resistance calculated at the (n-1)th time or earlier, for example, based on whether or not the difference is below a predetermined threshold. Alternatively, the evaluation unit 112 may evaluate the degree of dispersion based on the resistance of the solid-liquid mixture itself, for example, based on whether or not the resistance is below a predetermined threshold. The threshold can be set as appropriate based on the designer's empirical knowledge or experiments, simulations, or the like conducted by the designer.

[0045] As an example, the evaluation result of the evaluation unit 112 is sent to the control device 24. The control device 24 may display the evaluation result of the evaluation unit 112 on a monitor (not shown). Furthermore, when the evaluation unit 112 evaluates that the degree of dispersion meets the pass criterion, the control device 24 may notify the user of the dispersion evaluation support device 100 of the evaluation result by a known notification method. The notification method is not particularly limited, and known methods such as generating a notification sound or turning on a notification light can be used. These methods allow the user to monitor the progress of the dispersion processing in real time. Furthermore, the user can more quickly grasp the degree of dispersion.

[0046] Furthermore, the voltage and current values ​​measured by the measuring unit 108 may be sent to the control device 24. The control device 24 may display the waveforms of the voltage and current values ​​on an oscilloscope (not shown). Furthermore, the resistance, standard deviation σ, amount of change in resistance per unit time, etc. calculated by the calculation unit 110 may be sent to the control device 24. The control device 24 may display these values ​​on a monitor. In this case, the user can evaluate the degree of dispersion from the values ​​displayed on the monitor. When the calculation results of the calculation unit 110 are used by the user, the evaluation unit 112 may be omitted.

[0047] For example, execution of the process for evaluating the degree of dispersion can be instructed by a user via the control device 24 or by an operating program in the control device 24. The same applies to changing the settings of the process for evaluating the degree of dispersion. The control device 24 may also control the dispersing device 2, the valve 4, and the pump 6.

[0048] For example, the control device 24 drives the dispersing device 2 to perform a dispersion treatment of the solid-liquid mixture. When performing the dispersion treatment, the control device 24 controls the valve 4 to drive the pump 6 so that the flow path of the solid-liquid mixture is on the return pipe 10 side. In this case, the solid-liquid mixture is subjected to a dispersion treatment in the dispersing device 2 while circulating through the feed pipe 8 and the return pipe 10. Alternatively, the control device 24 stops driving the pump 6 while performing the dispersion treatment of the solid-liquid mixture. In this case, the solid-liquid mixture is subjected to a dispersion treatment while remaining in the dispersing device 2.

[0049] After the dispersion process of the solid-liquid mixture has been performed for a predetermined time, the control device 24 instructs the dispersion evaluation support device 100 to perform an evaluation process of the degree of dispersion. In this evaluation process, the control device 24 controls the valve 4 to drive the pump 6 so that the flow path of the solid-liquid mixture is on the return pipe 10 side. If this state has already been reached in the dispersion process, this state is maintained. Furthermore, the control device 24 continues to drive the dispersion device 2. In other words, the dispersion process and the evaluation process are performed simultaneously in parallel.

[0050] The dispersion evaluation support device 100 can perform evaluation processing on the solid-liquid mixture that flows successively into the pipe 102 from the dispersion device 2. In other words, it can switch evaluation targets one after another. Because the dispersion processing continues even during the evaluation processing, the degree of dispersion of the solid-liquid mixture gradually increases, and therefore the resistance of the solid-liquid mixture gradually decreases. When the evaluation unit 112 evaluates that the degree of dispersion meets the pass criterion, the control device 24 stops operation of the dispersion device 2 and controls the valve 4 so that the flow path of the solid-liquid mixture is on the supply pipe 12 side. The operation of the pump 6 is maintained. As a result, a solid-liquid mixture whose degree of dispersion meets the pass criterion is supplied to the tank 14. Note that operation of the dispersion device 2 may be stopped during execution of the evaluation processing. In this case, the dispersion processing and the evaluation processing are alternately repeated until the degree of dispersion meets the pass criterion.

[0051] 5 is a flowchart showing an example of a dispersion processing method. This flow is executed repeatedly, for example, at a predetermined timing. First, the resistance of the solid-liquid mixture or the resistance of the standard solution is measured by an AC impedance method (S101). Then, based on the resistance measured in step S101, the operating frequency is determined (S102).

[0052] Next, the solid-liquid mixture is subjected to a dispersion treatment, and the solid-liquid mixture is flowed through the pipe 102. Then, an AC voltage having a frequency fixed to the operating frequency is applied between the first electrode 114 and the second electrode 116, or an AC current having a frequency fixed to the operating frequency is superimposed thereon (S103). As a result, the AC voltage is applied to the solid-liquid mixture in the space extending between the first position 102a and the second position 102b, or an AC current is superimposed thereon. Then, the current generated between the first electrode 114 and the second electrode 116 due to the application of the AC voltage is measured, or the voltage generated between the first electrode 114 and the second electrode 116 due to the superimposition of the AC current is measured (S104). Next, the standard deviation σ of the resistance is calculated using the measurement results from step S104 (S105).

[0053] Then, the degree of dispersion of the solid-liquid mixture is evaluated according to the calculation result in step S105. In this example, it is determined whether the calculated standard deviation σ is below a threshold value (S106). If the standard deviation σ of resistance is below the threshold value (Y in S106), the user is notified that the degree of dispersion of the solid-liquid mixture meets the pass criterion (S107), and this routine ends. If the standard deviation σ of resistance is equal to or greater than the threshold value (N in S106), this routine ends without notifying the user.

[0054] As described above, the distributed processing system 1 according to this embodiment includes a dispersion device 2 and a dispersion evaluation support device 100. The dispersion evaluation support device 100 measures resistance, which serves as an evaluation index for the degree of dispersion, by applying an AC voltage or superimposing an AC current on the solid-liquid mixture. This can support the evaluation of the degree of dispersion of the conductive solid in the dispersion treatment of the conductive solid. Therefore, the dispersion treatment of the conductive solid can be performed while understanding the degree of dispersion of the conductive solid in the solid-liquid mixture. Preferably, the calculation unit 110 calculates the standard deviation of the resistance or the amount of change in resistance per unit time. This can further improve the accuracy of the evaluation of the degree of dispersion.

[0055] Furthermore, the power supply unit 106 fixes the frequency of the AC voltage applied to the solid-liquid mixture or the AC current superimposed thereon to the operating frequency. This makes it possible to further improve the accuracy of the evaluation of the degree of dispersion. It also makes it possible to shorten the time required to evaluate the degree of dispersion. Furthermore, because an electric field is generated in the solid-liquid mixture flowing inside the pipe 102, it is possible to evaluate the degree of dispersion while the solid-liquid mixture is being transported. In other words, it is possible to realize an in-line evaluation process of the degree of dispersion. Furthermore, since there is no need for work such as sampling, the degree of dispersion can be easily evaluated.

[0056] As an example, the solid-liquid mixture is an electrode slurry containing a solvent and at least one of an electrode active material and a conductive additive. In this case, evaluating the degree of dispersion can improve the performance of the power storage device. Furthermore, the dispersion evaluation support device 100 can be attached to an existing device by simply using part of the piping in the device as the piping 102 or by replacing part of the piping with the piping 102 of the dispersion evaluation support device 100. Therefore, the dispersion evaluation support device 100 is easy to install, replace, and maintain.

[0057] The configuration of each part of the distributed processing system 1 is not limited to that described above. For example, the solid-liquid mixture may be sent directly to the next process without being stored in the tank 14. Furthermore, multiple dispersion evaluation support devices 100 may be arranged in parallel with the dispersing device 2. For example, the feed pipe 8 may be configured with two pipes 102 connected in parallel to the dispersing device 2 and the pump 6, and a dispersion evaluation support device 100 may be provided for each pipe 102. This reduces pressure loss in the flow of the solid-liquid mixture due to the installation of the dispersion evaluation support devices 100. Furthermore, increasing the number of dispersion evaluation support devices 100 increases the speed of the dispersion degree evaluation process. Furthermore, by changing the dispersion degree evaluation index in each dispersion evaluation support device 100, it becomes possible to grasp the dispersion degree in more detail, which may lead to improved evaluation accuracy of the dispersion degree.

[0058] 6 is a schematic diagram of a distributed processing system 1 according to embodiment 2. The following description of this embodiment will focus on configurations that are different from embodiment 1, and common configurations will be explained briefly or omitted.

[0059] The distributed processing system 1 of this embodiment includes a distribution device 2, a pump 6, a control device 24, a distributed evaluation support device 100, a first tank 204, a second tank 206, a first pipe 208, a second pipe 210, and a third pipe 212.

[0060] The dispersion device 2, the control device 24, and the dispersion evaluation support device 100 have the same configurations as the dispersion device 2, the control device 24, and the dispersion evaluation support device 100 according to the first embodiment, respectively. The first tank 204 stores, at least temporarily, a solid-liquid mixture before the degree of dispersion is evaluated by the dispersion evaluation support device 100. For example, a solid-liquid mixture is introduced into the first tank 204 from outside the distributed processing system 1. The second tank 206 stores a solid-liquid mixture whose degree of dispersion is evaluated by the dispersion evaluation support device 100 to be equal to or greater than a predetermined value. For example, the second tank 206 stores a solid-liquid mixture whose degree of dispersion is evaluated to satisfy the pass standard.

[0061] The first pipe 208 has one end connected to the first tank 204 and the other end connected to the distributed assessment support device 100. The second pipe 210 has one end connected to the distributed assessment support device 100 and the other end connected to the first tank 204. The third pipe 212 has one end connected to the distributed assessment support device 100 and the other end connected to the second tank 206. The distribution device 2 is disposed midway along the first pipe 208.

[0062] The distributed processing system 1 of this embodiment also has a first switching valve 214 and a fourth pipe 216. The first switching valve 214 can be configured with a known valve such as an electromagnetic three-way valve. The first switching valve 214 is disposed in the first pipe 208 between the dispersion device 2 and the dispersion evaluation support device 100. One end of the fourth pipe 216 is connected to the first switching valve 214, and the other end is connected to the first tank 204. The first switching valve 214 can switch whether the solid-liquid mixture that has passed through the dispersion device 2 is sent to the dispersion evaluation support device 100 via the first pipe 208 or to the first tank 204 via the fourth pipe 216.

[0063] The distributed processing system 1 of this embodiment also includes a second switching valve 218. The second switching valve 218 can be configured as a known valve such as a three-way electromagnetic valve. The second switching valve 218 is disposed midway through the second pipe 210 and the third pipe 212. In this embodiment, the second pipe 210 and the third pipe 212 are configured as a common pipe between the distributed evaluation support device 100 and the second switching valve 218. The second pipe 210 and the third pipe 212 are configured as different pipes downstream of the second switching valve 218. The second switching valve 218 can switch whether the solid-liquid mixture that has passed through the distributed evaluation support device 100 is sent to the first tank 204 via the second pipe 210 or to the second tank 206 via the third pipe 212. The pump 6 is disposed midway through the first pipe 208. By driving the pump 6, the solid-liquid mixture can be flowed from the first tank 204 to each pipe.

[0064] The control device 24 acquires the evaluation results from the dispersion evaluation support device 100, and controls the first switching valve 214 and the second switching valve 218 in accordance with the evaluation results to switch the flow path of the solid-liquid mixture. The control device 24 also controls the operation of the dispersion device 2 and the pump 6. As an example, the control device 24 can control the distributed processing system 1 to assume one of first to third states. In Figure 6, the flow of the solid-liquid mixture in the first state is indicated by arrow I, the flow of the solid-liquid mixture in the second state is indicated by arrow II, and the flow of the solid-liquid mixture in the third state is indicated by arrow III.

[0065] In the first state, the first switching valve 214 is controlled so that the solid-liquid mixture that has passed through the dispersing device 2 returns to the first tank 204 via the fourth pipe 216. Then, the dispersing device 2 and the pump 6 are driven. This causes the solid-liquid mixture to circulate between the first tank 204 and the dispersing device 2. As a result, the solid-liquid mixture is subjected to a dispersion treatment. After the first state has continued for a predetermined time, the control device 24 switches the distributed processing system 1 to the second state. This predetermined time can be set appropriately based on the designer's empirical knowledge or experiments or simulations performed by the designer. As an example, even when the state of the distributed processing system 1 is switched, the dispersing device 2 and the pump 6 remain driven.

[0066] In the second state, the first switching valve 214 is controlled so that the solid-liquid mixture that has passed through the dispersing device 2 is directed toward the dispersion evaluation support device 100 via the first pipe 208. Furthermore, the second switching valve 218 is controlled so that the solid-liquid mixture that has passed through the dispersion evaluation support device 100 is returned to the first tank 204 via the second pipe 210. Furthermore, an instruction to execute an evaluation process is given to the dispersion evaluation support device 100. As a result, the solid-liquid mixture flows from the first tank 204 via the first pipe 208, through the dispersing device 2, and into the dispersion evaluation support device 100. After the degree of dispersion is evaluated, the solid-liquid mixture flows from the dispersion evaluation support device 100 to the first tank 204 via the second pipe 210. Thus, the solid-liquid mixture circulates between the first tank 204, the dispersing device 2, and the dispersion evaluation support device 100. When the distributed processing system 1 assumes the second state, the solid-liquid mixture that has been subjected to the dispersion process can be subjected to a process to evaluate the degree of dispersion.

[0067] When the control device 24 acquires from the dispersion evaluation support device 100 an evaluation result indicating that the degree of dispersion satisfies the pass criterion, the control device 24 switches the distributed processing system 1 to the third state after a predetermined time has elapsed since the acquisition. The predetermined time is, for example, the time it takes for the solid-liquid mixture present in the piping from the dispersion evaluation support device 100 to the second switching valve 218 to finish passing through the second switching valve 218. By waiting the predetermined time from the acquisition of the evaluation result until the switching to the third state, it is possible to prevent the solid-liquid mixture that has passed through the dispersion evaluation support device 100 before the degree of dispersion is evaluated to satisfy the pass criterion from being sent to the second tank 206.

[0068] In the third state, the first switching valve 214 is controlled so that the solid-liquid mixture that has passed through the dispersing device 2 is directed toward the dispersion evaluation support device 100 via the first piping 208. Furthermore, the second switching valve 218 is controlled so that the solid-liquid mixture that has passed through the dispersion evaluation support device 100 is directed toward the second tank 206 via the third piping 212. As a result, the solid-liquid mixture flows from the first tank 204 to the dispersion evaluation support device 100 via the first piping 208, and flows from the dispersion evaluation support device 100 to the second tank 206 via the third piping 212. As a result, a solid-liquid mixture whose degree of dispersion meets the pass criterion can be stored in the second tank 206.

[0069] Furthermore, when the control device 24 receives an evaluation result from the distribution evaluation support device 100 indicating that the degree of dispersion does not meet the pass criterion while the distributed processing system 1 is in the third state, the control device 24 immediately switches the distributed processing system 1 to the second state. That is, the control device 24 switches the flow path of the solid-liquid mixture between the second pipe 210 and the third pipe 212 in accordance with the evaluation result of the distribution evaluation support device 100. This makes it possible to more reliably guarantee that the degree of dispersion of the solid-liquid mixture stored in the second tank 206 meets the pass criterion. Furthermore, as an example, when a new solid-liquid mixture is added to the first tank 204, the control device 24 switches the distributed processing system 1 to the first state and repeats the above-described flow.

[0070] The structure of the distributed processing system 1, including the arrangement of each pipe, pump 6, and each switching valve, is not limited to that shown in FIG. 6 and can be modified as appropriate. For example, when the distributed processing system 1 is in the second state, a solid-liquid mixture evaluated to have an insufficient degree of dispersion may be returned from the dispersion evaluation support device 100 to the dispersing device 2 without passing through the first tank 204, or may be circulated between the dispersing device 2 and a tank other than the first tank 204 and the second tank 206. This allows the solid-liquid mixture that has been subjected to dispersion treatment in the dispersing device 2 and the solid-liquid mixture that remains in the first tank 204 and has not been subjected to dispersion treatment in the dispersing device 2 to be handled separately. This makes it possible to suppress mixing of these solid-liquid mixtures and improve the efficiency of the dispersion treatment.

[0071] The above describes the embodiments of the present disclosure in detail. The above-described embodiments merely illustrate specific examples of implementing the present disclosure. The content of the embodiments does not limit the technical scope of the present disclosure, and many design modifications, such as changing, adding, or deleting components, are possible within the scope of the concept of the present disclosure defined in the claims. A new embodiment with design modifications will combine the effects of the combined embodiments and modifications. In the above-described embodiments, the content in which such design modifications are possible is emphasized by using notations such as "in this embodiment" or "in this embodiment," but design modifications are also permitted even in content without such notation. Any combination of the above components is also valid as an aspect of the present disclosure. Hatching in cross sections in the drawings does not limit the material of the hatched object.

[0072] The invention according to the above-described embodiment may be specified by the following items. [Item 1] A dispersion device (2) for dispersing a conductive solid in a solid-liquid mixture containing a solvent and a conductive solid, and a dispersion evaluation support device (100) for supporting evaluation of the degree of dispersion of the conductive solid in the solid-liquid mixture, wherein the dispersion evaluation support device (100) comprises: a pipe (102) through which the solid-liquid mixture that has been subjected to the dispersion treatment flows; a first electrode (114) and a second electrode (116) disposed in the pipe (102), the first electrode (114) and the second electrode (116) being disposed so as to be able to apply an AC voltage or to be able to superimpose an AC current to the solid-liquid mixture in a space extending between a first position (102a) of the pipe (102) and a second position (102b) displaced from the first position (102a) in the extension direction of the pipe (102); a power supply unit (106) for applying an AC voltage or superimposing an AC current between the first electrode (114) and the second electrode (116); A distributed processing system (1) comprising: a measurement unit (108) that measures a current generated between a first electrode (114) and a second electrode (116) by applying an AC voltage, or that measures a voltage generated between the first electrode (114) and the second electrode (116) by superimposing an AC current; and a calculation unit (110) that calculates a resistance of the solid-liquid mixture, which serves as an index of the degree of dispersion of a conductive solid in the solid-liquid mixture, using the measurement results of the measurement unit (108). [Item 2] The distributed processing system (1) of Item 1, in which the calculation unit (110) calculates a standard deviation of the resistance as the index. [Item 3] The distributed processing system (1) of Item 1, in which the calculation unit (110) calculates a change in resistance per unit time as the index. [Item 4] The distributed processing system (1) according to any one of Items 1 to 3, wherein the power supply unit (106) applies an AC voltage whose frequency is fixed to a predetermined operating frequency, or superimposes an AC current whose frequency is fixed to the operating frequency, and the operating frequency is determined based on the resistance of the solid-liquid mixture or the resistance of a standard solution in which the conductive solid has been dispersed to a predetermined degree, measured by an AC impedance method.[Item 5] The dispersion evaluation support device (100) is provided with an evaluation unit (112) that evaluates the degree of dispersion of the conductive solid in the solid-liquid mixture according to the calculation result of the calculation unit (110). [Item 6] The dispersion processing system (1) of any of items 1 to 5, wherein the solid-liquid mixture is an electrode slurry containing at least one of an electrode active material and a conductive additive as the conductive solid. [Item 7] A first tank (204) for at least temporarily storing a solid-liquid mixture before the dispersion degree of the conductive solid is evaluated by the dispersion evaluation support device (100); a second tank (206) for storing a solid-liquid mixture whose dispersion degree has been evaluated by the dispersion evaluation support device (100) to be equal to or greater than a predetermined value; a first pipe (208) connected to the first tank (204) and the dispersion evaluation support device (100) and having a dispersion device (2) disposed midway through, through which the solid-liquid mixture flows from the first tank (204) toward the dispersion evaluation support device (100); a second pipe (210) connected to the dispersion evaluation support device (100) and the first tank (204) and through which the solid-liquid mixture flows from the dispersion evaluation support device (100) toward the first tank (204); A fifth item of the distributed processing system (1) comprises: a third pipe (212) connected to the distributed evaluation support device (100) and the second tank (206), through which a solid-liquid mixture flows from the distributed evaluation support device (100) toward the second tank (206); and a control device (24) that switches the flow path of the solid-liquid mixture between the second pipe (210) and the third pipe (212) depending on the evaluation result of the distributed evaluation support device (100). [Item 8] A dispersion treatment method comprising: subjecting a solid-liquid mixture containing a solvent and a conductive solid to a dispersion treatment of the conductive solid; flowing the dispersed solid-liquid mixture through a pipe (102); applying an AC voltage or superimposing an AC current to the solid-liquid mixture in a space extending between a first position (102a) of the pipe (102) and a second position (102b) shifted from the first position (102a) in the extension direction of the pipe (102); measuring the current generated by the application of the AC voltage or measuring the voltage generated by the superimposition of the AC current; and using the measurement results, calculating the resistance of the solid-liquid mixture, which is an index of the degree of dispersion of the conductive solid in the solid-liquid mixture.

[0073] The present disclosure relates to a distributed processing system and a distributed processing method.

[0074] 1 Distributed processing system, 2 Distributed device, 14 Tank, 24 Control device, 100 Distributed evaluation support device, 102 Piping, 106 Power supply unit, 108 Measurement unit, 110 Calculation unit, 112 Evaluation unit, 114 First electrode, 116 Second electrode, 204 First tank, 206 Second tank, 208 First piping, 210 Second piping, 212 Third piping.

Claims

1. A dispersed processing system comprising: a dispersing device that subjects a solid-liquid mixture containing a solvent and a conductive solid to a dispersion treatment of the conductive solid; and a dispersion evaluation support device that supports evaluation of the degree of dispersion of the conductive solid in the solid-liquid mixture, wherein the dispersion evaluation support device comprises: a pipe through which the solid-liquid mixture that has been subjected to the dispersed treatment flows; first and second electrodes disposed within the pipe, the first and second electrodes being disposed so that an AC voltage can be applied to the solid-liquid mixture in a space extending between a first position in the pipe and a second position shifted from the first position in the extension direction of the pipe, or so that an AC current can be superimposed on the solid-liquid mixture; a power supply unit that applies an AC voltage or superimposes an AC current between the first and second electrodes; a measurement unit that measures the current generated between the first and second electrodes by applying the AC voltage, or measures the voltage generated between the first and second electrodes by superimposing the AC current; and a calculation unit that uses the measurement results of the measurement unit to calculate the resistance of the solid-liquid mixture, which is an index of the degree of dispersion of the conductive solid in the solid-liquid mixture.

2. The distributed processing system according to claim 1, wherein the calculation unit calculates a standard deviation of the resistance as the index.

3. The distributed processing system according to claim 1, wherein the calculation unit calculates the amount of change in the resistance per unit time as the index.

4. A distributed processing system according to any one of claims 1 to 3, wherein the power supply unit applies an AC voltage whose frequency is fixed at a predetermined operating frequency, or superimposes an AC current whose frequency is fixed at the operating frequency, and the operating frequency is determined based on the resistance of the solid-liquid mixture or the resistance of a standard solution in which the conductive solid has a predetermined degree of dispersion, measured by an AC impedance method.

5. A distributed processing system according to any one of claims 1 to 3, wherein the dispersion evaluation support device comprises an evaluation unit that evaluates the degree of dispersion of the conductive solid in the solid-liquid mixture according to the calculation result of the calculation unit.

6. The distributed processing system according to any one of claims 1 to 3, wherein the solid-liquid mixture is an electrode slurry containing at least one of an electrode active material and a conductive additive as the conductive solid.

7. The distributed processing system according to claim 5, comprising: a first tank for at least temporarily storing the solid-liquid mixture before the degree of dispersion of the conductive solid is evaluated by the dispersion evaluation support device; a second tank for storing the solid-liquid mixture whose degree of dispersion has been evaluated by the dispersion evaluation support device to be equal to or greater than a predetermined value; a first pipe connected to the first tank and the dispersion evaluation support device, with the disperser disposed midway, and through which the solid-liquid mixture flows from the first tank to the dispersion evaluation support device; a second pipe connected to the dispersion evaluation support device and the first tank, and through which the solid-liquid mixture flows from the dispersion evaluation support device to the first tank; a third pipe connected to the dispersion evaluation support device and the second tank, and through which the solid-liquid mixture flows from the dispersion evaluation support device to the second tank; and a control device for switching the flow path of the solid-liquid mixture between the second pipe and the third pipe depending on the evaluation result of the dispersion evaluation support device.

8. A dispersion treatment method comprising: subjecting a solid-liquid mixture containing a solvent and a conductive solid to a dispersion treatment of the conductive solid; flowing the dispersed solid-liquid mixture through a pipe; applying an AC voltage or superimposing an AC current to the solid-liquid mixture in a space extending between a first position in the pipe and a second position shifted from the first position in an extension direction of the pipe; measuring the current generated by the application of the AC voltage or measuring the voltage generated by the superimposition of the AC current; and using the measurement results, calculating the resistance of the solid-liquid mixture, which is an index of the degree of dispersion of the conductive solid in the solid-liquid mixture.

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