JP2018041592A - Cell stack, laminate battery, electrolytic cell, and dialysis tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a cell stack which enables the realization of weight reduction and lower cost, and which is arranged so that a liquid solution can be efficiently fed to the inside while keeping down a slit flow resistance and leak current; a laminate battery having the cell stack; an electrolytic cell; and a dialysis tank.SOLUTION: A cell stack is applicable to a laminate battery, an electrolytic cell, or a dialysis tank, into which a liquid solution is charged. The cell stack comprises: at least one or more frames 11, 21; inflow slit tubes 12, 22 extending through the at least one or more frames for letting the liquid solution flow to the inside; outflow slit tubes 13, 23 extending through the at least one or more frames for letting the liquid solution flow to the outside; a diaphragm 14 for isolating the liquid solution in the at least one or more frames; and an electrode plate 15 for partially isolating the at least one or more frames. The at least one or more frames are formed by a closed-cell resin. In the cell stack, a plural number of the inflow slit tubes and a plural number of the outflow slit tubes are included per at least one frame.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cell stack applicable to a laminated battery, an electrolytic cell, or a dialysis tank, and a laminated battery, an electrolytic cell, and a dialysis tank having the cell stack.

  An integrated cell stack in which a plurality of unit cells (cell units) are stacked has been proposed and prototyped for application to laminated batteries, electrolytic tanks, dialysis tanks, and the like.

  For example, Patent Document 1 discloses a cell stack for a redox flow battery in which a cell frame, an electrode, and a diaphragm are stacked, and the cell frame includes a frame frame and a bipolar plate integrated with the frame frame, Describes a cell stack for a redox flow battery, characterized in that the cell stack is closely attached to the bipolar plate with a clamping force without being bonded to the bipolar plate.

  In such a redox flow battery cell, in order to supply and drain the electrolytic solution to the positive electrode chamber and the negative electrode chamber, a single hole-shaped liquid supply portion and waste liquid portion are usually provided at the end of the rectangular electrode chamber. Provided.

  For example, in Patent Document 2, an electrolytic solution is circulated so as to enter the cell stack from the inlet provided in the cell stack, and to exit to the outside from the outlet provided in the cell stack after the electrode reaction. An electrolyte circulation type secondary battery for charging and discharging, wherein an inlet and an outlet are provided on a side surface portion of the cell stack parallel to the stacking direction. A cell stack is described.

JP 2002-367660 A JP-A-2-183968

  Such a cell stack needs to increase the number of stacked unit cells (cell units) in order to realize high capacity and large scale. However, as the number of layers increases, the weight and cost of the entire cell stack increase.

  In addition, regarding the means for feeding the solution into the cell stack, a method of making the slit for guiding the electrolyte from the manifold to each electrode chamber into a tube shape and communicating with the manifold provided outside the cell stack also takes a long slit for electric discharge. This was carried out in order to increase the resistance and reduce the leakage current value flowing through the manifold.

However, it is not practical to increase the thickness of the electrode chamber and increase the slit tube diameter to secure a sufficient amount of liquid feeding because the internal resistance of the cell is increased. Here, it is possible to increase the flow rate by increasing the liquid supply pressure, but the pressure (pump discharge pressure) may exceed 5 kg / cm ^2, and the pressure durability of the cell There was a new problem of having

  In such a cell stack, in order to maintain good uniformity of liquid feeding to each cell, generally, the flow resistance by the liquid permeable electrode needs to be 10 times or more the flow resistance by the slit. It was important how small the flow resistance could be suppressed. As a solution to this, it was effective to increase the cross-sectional area of the slit, but to that end, it was necessary to form a large number of grooves in the hard frame, which was an obstacle to weight reduction and cost reduction. It was.

  The present invention has been made in view of the above problems, and realizes a reduction in weight and cost, and a cell stack capable of efficiently feeding a solution into the interior while suppressing slit flow resistance and leakage current, And it aims at providing the laminated battery which has the said cell stack, an electrolytic vessel, and a dialysis tank.

  One embodiment of the present invention is a cell stack which is applied to a stacked battery, an electrolytic cell, or a dialysis tank and is filled with a solution, and includes at least one frame and a solution penetrating the frame. An inflow slit tube for inflow, an outflow slit tube for allowing the solution to flow out through the frame body, a diaphragm for separating the solution in the frame body, and an electrode plate for separating a part of the frame body. A plurality of inflow slit tubes and outflow slit tubes are provided for at least one frame body.

  According to one aspect of the present invention, the frame body is made of closed cell resin to realize weight reduction and cost reduction, and a plurality of inflow slit tubes and outflow slit tubes are provided for at least one frame body. By doing so, it is possible to efficiently feed the solution to the cell stack while suppressing the slit flow resistance and the leakage current.

  At this time, according to one embodiment of the present invention, the sum of the cross-sectional areas in the inflow slit tube or the outflow slit tube is 5% or more and 30% or less of the cross-sectional area of the surface perpendicular to the direction in which the solution in the frame flows. can do.

  According to one aspect of the present invention, it is most preferable that the ratio of the cross-sectional area of the slit tube is within the above numerical range in terms of efficiently feeding the solution to the cell stack.

  In one embodiment of the present invention, the frame may be made of a resin containing polyvinyl chloride and / or polyvinylidene chloride.

  Polyvinyl chloride and polyvinylidene chloride are desirable in terms of weight reduction, and are excellent in adhesion and fusion properties, and thus are suitable for lamination.

  In one embodiment of the present invention, a solution permeable electrode is provided inside the frame, and the permeation resistance of the solution in the electrode is 10 times or more the permeation resistance of the inflow slit tube or the outflow slit tube.

  By designing the number of inflow slit tubes or outflow slit tubes so that the permeation resistance ratio falls within the above numerical range, the solution can be efficiently fed to the cell stack.

  Another aspect of the present invention is a laminated battery having the above-described cell stack, and the cell stack is formed by laminating a frame, a diaphragm, and an electrode plate as an electrode plate by bonding and / or fusing. The active material liquid flows in the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided by adhesion and / or fusion.

  As described above, if a stacked battery is configured using the above-described cell stack structure, the stacked battery can be realized while reducing the weight and cost of the stacked battery and suppressing the slit flow resistance and leakage current. The active material liquid can be fed efficiently to

  At this time, in another aspect of the present invention, the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a current collecting terminal so that it can be directly input / output from / to the outside of the cell stack. Good.

  Thus, by having an intermediate | middle input / output terminal between the laminated | stacked single battery units, it can be set as the laminated battery which can input / output efficiently.

  Another aspect of the present invention is an electrolytic cell having the above-described cell stack, wherein the cell stack is formed by laminating a frame, a diaphragm, and an electrode plate as an electrode plate by adhesion and / or fusion. The electrolyte flows through the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided by adhesion and / or fusion to the body.

  Thus, if an electrolytic cell is configured using the structure of the cell stack described above, the cell stack can be reduced in weight and cost, and the electrolytic cell can be configured by suppressing slit flow resistance and leakage current. It is possible to efficiently feed the electrolyte solution.

  At this time, in another aspect of the present invention, the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a current collecting terminal so that it can be directly input / output from / to the outside of the cell stack. Good.

  Thus, by having an intermediate | middle input / output terminal between the laminated electrolytic cell units, it can be set as the electrolytic cell which can input / output efficiently.

  Further, another aspect of the present invention is a dialysis tank having the above-described cell stack, wherein the cell stack is formed by laminating a frame, a diaphragm, and an electrode plate as a current collector plate by adhesion and / or fusion, The liquid to be treated or the concentration solution flows through the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided by adhesion and / or fusion to the frame.

  As described above, if the dialysis tank is configured using the structure of the cell stack described above, the dialysis tank can be reduced in weight and cost, and the dialysis tank can be configured by suppressing the slit flow resistance and leakage current. The solution can be fed efficiently to

  At this time, in another aspect of the present invention, the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a current collecting terminal so that it can be directly input / output from / to the outside of the cell stack. Good.

  Thus, by having an intermediate | middle input / output terminal between the laminated | stacked dialysis tank units, it can be set as an efficient dialysis tank.

  As described above, according to the present invention, the entire cell stack can be reduced in weight and cost, and the slit flow resistance and leakage current can be suppressed, and the liquid distribution to the cell stack can be favorably maintained. .

It is a disassembled perspective view which shows an example of a structure of the cell stack which concerns on one Embodiment of this invention. It is a figure which shows an example of a structure of a part of cell stack concerning one Embodiment of this invention. It is a disassembled perspective view which shows an example of a structure of the laminated battery or the electrolytic cell to which the cell stack which concerns on one Embodiment of this invention is applied. It is a perspective view which shows an example of a structure of the dialysis tank to which the cell stack which concerns on one Embodiment of this invention is applied.

DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail in the following order with reference to the drawings. The present embodiment described below does not unduly limit the contents of the present invention described in the claims, and all the configurations described in the present embodiment are essential as means for solving the present invention. Not necessarily.
1. Cell stack 1-1. Frame 1-2. Inflow slit tube and outflow slit tube 1-3. Diaphragm 1-4. Electrode plate 1-5. Electrode 2. Stacked battery 3. Electrolyzer 4. Dialysis tank

<1. Cell stack>
FIG. 1 is an exploded perspective view showing an example of the configuration of a cell stack according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a partial configuration of the cell stack according to the embodiment of the present invention. One embodiment of the present invention is a cell stack 10 that is applied to a laminated battery, an electrolytic cell, or a dialysis tank and is filled with a solution, and includes at least one or more frame bodies 11, 21 and frame bodies 11, 21. Flow-in slit tubes 12 and 22 through which the solution flows into the inside, flow-out slit tubes 13 and 23 through which the solution flows out through the frame, a diaphragm 14 separating the solution in the frame, and a frame 21, the frame bodies 11, 21 are made of closed cell resin, and a plurality of inflow slit tubes 12, 22 and outflow slit tubes 13, 23 are provided for at least one frame body 11, 21. It is characterized by being.

  Thus, weight reduction and cost reduction are realized by configuring the frame bodies 11 and 21 with closed cell resin, and the inflow slit pipes 12 and 22 and the outflow slit pipes 13 and 23 are at least one frame body 11, 21. By providing a plurality of them, it is possible to efficiently feed the solution to the cell stack 10 while suppressing the slit flow resistance and the leakage current. Hereinafter, each component of the cell stack 10 according to an embodiment of the present invention will be described, and the laminated battery 40, the electrolytic cell 40, and the dialysis tank 60 using the cell stack 10 will also be described.

(1-1. Frame)
Frame bodies 11 and 21 used in cell stack 10 concerning one embodiment of the present invention are constituted by closed cell resin. The closed cells are those in which bubbles containing air are not connected, thereby preventing the solution from passing through the resin. Moreover, since such closed cell resin is lightweight, even if it is a case where many cell units are laminated | stacked like the cell stack 10, the whole weight can be restrained.

  The frames 11 and 21 are not particularly limited as long as they are closed-cell resins, but are preferably made of a resin containing polyvinyl chloride (PVC) and / or polyvinylidene chloride (PVDC). Polyvinyl chloride and polyvinylidene chloride are desirable in terms of weight reduction and are suitable for lamination because they have excellent adhesion and fusion properties.

  The frames 11 and 21 are partitioned by a diaphragm 14 and an electrode plate 15 which will be described later according to the application. As an example, as shown in FIG. 1, the frame body 11 and the frame body 21 are separated by a diaphragm 14, and the other end side of the frame body 21 is partitioned by an electrode plate 15. The configuration of FIG. 1 shows a part of the cell stack. In practice, a cell stack composed of a number of layers can be configured by being stacked in layers in this order. At this time, the plurality of frames 11 and 21 are preferably laminated by adhesion or fusion via the diaphragm 14 or the electrode plate 15. By integrating the frames 11 and 21 with the diaphragm 14 and the electrode plate 15 by bonding or heat fusion, when the number of stacked cells increases, the force to hold the cell stack 10 with a bolt or the like is reduced. And the weight of the entire cell stack 10 can be reduced.

  Moreover, since the frame bodies 11 and 21 are formed with closed-cell resin, it is good also as a structure compressed by the thickness direction by the pressure at the time of lamination | stacking, and making it thin. By doing so, it is possible to realize a thin layer of the entire cell stack 10. In addition, when thinning the frame bodies 11 and 21 by pressurization, the inflow slit tube, the outflow slit tube, the electrode, and the like provided in the frame bodies 11 and 21 are considered in thinning of the frame bodies 11 and 21. It is desirable to design in

  When the cell stack 10 according to an embodiment of the present invention is used in a laminated battery or an electrolytic cell, the cell unit 30 includes a liquid-permeable electrode 34 inside a frame 31 as shown in FIG. It can be constituted as follows. At this time, each electrode plate 15 is in contact with the electrode 34 of the adjacent frame, and the electrode plate 15 is preferably provided with a current collecting terminal 16. And, as will be described later, by adjusting the number of cells stacked in series, the function of a DC-DC converter can be provided.

(1-2. Inflow slit tube and outflow slit tube)
The cell stack frames 11 and 21 include inflow slit tubes 12 (12A, 12B, and 12C) and 22 (22A, 22B, and 22C) and an outflow slit tube 13 (13A) that are slit-like piping for circulating the solution. , 13B, 13C), 23 (23A, 23B, 23C). The inflow slit tubes 12 and 22 and the outflow slit tubes 13 and 23 are made of, for example, polyvinyl chloride (PVC), and are bonded to the frames 11 and 21 with a solvent (for example, acetone) or melted. Preferably it is worn. Thereby, the slit flow resistance and the leakage current from the slit can be suppressed.

The plurality of inflow slit tubes 12, 22 or outflow slit tubes 13, 23 has a total cross-sectional area of 5% or more of the cross-sectional area of the surface perpendicular to the direction in which the solution in the frames 11, 21 flows, 30% or less is preferable. It is desirable that the ratio of the sectional area of the slit tube be within this numerical range in terms of efficiently feeding the solution to the cell stack. For example, when the inside is a frame having a thickness of 3 mm, a width of 30 mm, and a height of 20 mm, and a slit tube having an inner diameter of 1.5 mm is provided perpendicular to the width direction, the sectional area of one slit tube is about 1 a .8Mm ^2, the cross-sectional area in a plane perpendicular to the direction of circulation 90 mm ^2, and the order that the proportion is about 2.0%, the slit tube to the ratio of the cross-sectional area 5% or more It is preferable that there are three or more. When the ratio of the cross-sectional area is less than 5%, the flow resistance in the slit becomes too high. On the other hand, when the ratio of the cross-sectional area exceeds 30%, the leakage current flowing through the slit tube and the manifold is excessively increased, which is not efficient.

  The inflow slit tube 32 (32A, 32B, 32C) and / or the outflow slit tube 33 (33A, 33B, 33C) are, for example, attached to the outside with an inflow manifold 37 and / or an outflow manifold 38 as shown in FIG. It is preferable that In this way, the loss due to leakage current can be reduced, and the solution can be efficiently fed into the frame of the cell stack. Further, by providing a plurality of inflow slit pipes 32 and / or outflow slit pipes 33 with inflow side opening / closing valves 35 (35A, 35B, 35C) and / or outflow side opening / closing valves 36 (36A, 36B, 36C), It is preferable that the number of slit tubes to be used can be adjusted according to the situation. In FIG. 2, the inflow slit tube 32 and / or the outflow slit tube 33 are inserted from the upper part of the frame body 31, but may be inserted from the left and right sides of the frame body 31. When the solution permeable electrode is provided inside the frame, it is preferable that the permeation resistance of the solution in the electrode is 10 times or more the permeation resistance of the inflow slit tube or the outflow slit tube. As a result, it is possible to easily realize equal distribution in the cell of the solution.

  The inflow slit tube 32 and the outflow slit tube 33 connected to the manifolds 37 and 38 circulate and supply the solution via a pump or the like. Furthermore, a control unit that measures numerical values such as the voltage of the cell stack or the voltage of an arbitrary cell unit 30 is provided, and by adjusting the transport of the solution by the pump (including on / off control), the required power for transporting the liquid can be reduced. It can also be greatly reduced. Furthermore, it may be used separately for the positive electrode and the negative electrode, such as a positive electrode pump and a negative electrode pump, and it is preferable to use a biaxial active material liquid feed pump capable of feeding the solution to both the positive electrode and the negative electrode. . For example, the pump power can be reduced by about 30% by using a double-shaft active material liquid feed pump. At this time, a stationary system in which the active material liquid is stopped may be used.

(1-3. Diaphragm)
The diaphragm 14 is mainly a cation or anion exchange membrane having a large proton conductivity. For example, ion exchange membranes such as fluororesins (Nafion (registered trademark) 117, 211, etc.), polystyrene sulfonic acids, polyolefins, etc. are used. There are examples of use such as outer filtration membrane (UF), nanofiltration membrane (NF), etc. The volume resistivity of the iron / chromium-based active material liquid is about 1 Ωcm, which is close to hydrochloric acid, but it uses sulfuric acid acidic vanadium as the active material. In this case, the resistance is several times or more, and it is necessary to pay sufficient attention to the ion exchange capacity and thickness of the diaphragm.

(1-4. Electrode plate)
In the cell stack 10 according to one embodiment of the present invention, the electrode plate 15 (bipolar partition plate, bipolar plate) is used to optimize input / output (voltage) using many intermediate input / output terminals (trim cell terminals). ) Is preferably a structure having a metal current collecting terminal 16. On the other hand, when the metal electrode plate 15 is used, it may be dissolved or hydrogen may be generated when it comes into contact with the active material liquid or the like in the cell. Therefore, in the present invention, for example, the electrode plate 15 can be formed by sandwiching a metal sheet between conductive resin sheets. In this way, the internal resistance (cell area resistivity) is reduced, and the current collecting terminal 16 is provided at one end of the electrode plate 15 so that a uniform potential distribution can be created over the entire surface of the electrode plate 15. No longer needed.

  As an example of the electrode plate 15 (bipolar plate), a configuration of carbon plastic sheet / copper sheet / carbon plastic sheet having a current collecting terminal or copper mesh / carbon plastic sheet is preferable. In the case of a bipolar plate with electrodes on both sides of the electrode plate 15, it is necessary to sandwich both sides of the metal sheet with a conductive resin sheet, but only one side of both ends of the cell stack 10 is an electrode. In the case of a monopolar partition plate (end plate) in contact with the electrode, only the surface in contact with the electrode may be covered with a conductive resin sheet.

  The average volume resistivity of the electrode plate 15 is 0.01 Ωcm or less, preferably 0.005 Ωcm or less, more preferably 0.001 Ωcm or less. Lowering the volume resistivity in the entire length direction is important for performing uniform charge / discharge reaction on the electrode surface and maintaining high voltage efficiency. However, in order to obtain a uniform potential distribution, such an electrode plate of 0.01 Ωcm needs to have a thickness of 3 to 5 mm or more, and the thickness of the small cell stack 10 is reduced to about 1 mm to 2 mm. In order to realize the production, it is preferable that the average volume resistivity is 0.005 Ωcm to 0.0005 Ωcm. For this purpose, it is necessary to use a highly conductive metal sheet or an electrode plate sandwiched with a mesh.

Further, it is preferable that the carbon plastic sheet is made of a thermoplastic resin such as polyethylene or polypropylene as the resin, and is integrated with the conductive carbon fiber nonwoven fabric as the electrode by means such as heat fusion or welding with a solvent. The resin of the carbon plastic sheet suitable for heat fusion is a polyolefin resin or the like, and the resin suitable for welding is polyvinyl chloride or the like. Thereby, the contact resistance between an electrode and a plate can be minimized. Contact resistance of both the case and without the fusion as sheet resistivity, respectively, a difference of about 0.01? Cm ² and 0.10Omucm ² is arise.

(1-5. Electrode)
When the cell stack according to the embodiment of the present invention is used in a laminated battery or an electrolytic cell, the electrode body 34 is provided in the frame 31 as shown in FIG. The electrode 34 is a porous conductor that circulates and impregnates the active material liquid, and the material is carbon or a metal such as lead. The electrode 34 is, for example, a carbon fiber felt (carbon fiber electrode). In addition, it is preferable from the viewpoint of the active material complementation that the carbon fibers constituting the carbon fiber electrode can be confirmed by microscopic observation (for example, scanning electron microscope (SEM)) with a fiber diameter of 5 μm or less.

Conventional fiber diameters of polyacrylonitrile (PAN), cellulose, pitch, quinol, and the like are in the range of about 7 to 12 μm, and no fiber having a diameter of 5 μm or less is usually present in observation by SEM. When such an electrode 34 (carbon fiber felt) was used, the current density capable of maintaining good voltage efficiency (for example, 85% or more) was up to about 100 mAcm ⁻² .

On the other hand, in the case of vapor-grown carbon fiber, the diameter is about 0.1 μm or less, and it becomes possible to perform electrolysis by high-dimensional diffusion. When used as an assembly electrode, a high current density (for example, static) Even in the system, 100 mAcm ⁻² ) can be obtained. In addition, a carbon fiber electrode having a thin fiber diameter can be obtained by electrolytic oxidation treatment or the like. Thus, by using a carbon fiber electrode with a reduced fiber diameter as the electrode 34, the output density in the battery body (electrolyzer) is increased, and the battery is reduced in size (in some cases, the size is ½ or less). The manufacturing cost can be greatly reduced. Actually, if the fiber diameter is about 5 μm or less, the mass mobility can be improved, and a current density of several hundred mAcm ⁻² can be achieved in the flow type.

Also, the carbon fiber felt may be subjected to electrolytic oxidation treatment in dilute sulfuric acid or the like. As a result, the fiber diameter becomes smaller and the surface is remarkably oxidized and the specific surface area is increased by 1 to 2 digits (for example, the BET specific surface area value by nitrogen gas is about 1 m ² / g to 10 to 100 m ² / increase to g). At the same time, oxygen elements are introduced on the surface as carbonyl groups, carboxyl groups, etc. (for example, the O / C ratio of ESCA is about 0.1% to 1-5%), increasing the electron transfer reaction rate in the charge / discharge reaction. As a result, gas generation as a side reaction can be suppressed by improving the overvoltage. Furthermore, you may make it improve a graphitization degree by baking at the temperature of 2000 to 2500 degreeC.

  By using such a carbon fiber electrode, the voltage efficiency is generally improved by 10% or more and the Coulomb efficiency excluding the leakage current loss (shunt current loss) of the manifold is improved by about 1 to 2% compared to the battery of the conventional electrode. Will be able to.

<2. Multilayer battery>
One embodiment of the present invention is a laminated battery having the above-described cell stack, and the cell stack is formed by laminating a frame, a diaphragm, and an electrode plate as an electrode plate by adhesion and / or fusion, and the frame. The active material liquid flows in the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided by adhesion and / or fusion.

  FIG. 3 is a perspective view showing an example of a configuration of a laminated battery to which a cell stack according to an embodiment of the present invention is applied or an electrolytic cell described later. A laminated battery 40 according to an embodiment of the present invention includes: a frame body 41 / an electrode plate 42 / a frame body 43 / a diaphragm 44 / a frame body 45 / an electrode plate 46 / a frame body 47 / a diaphragm 48 / a frame body 49. / The diaphragm 50 / the end plate 51, etc., have a structure in which a frame, a diaphragm, and an electrode plate as an electrode plate are stacked as a cell stack, and each frame has an electrode inside.

  In the laminated battery 40, the solution to be circulated is an active material liquid. The active material liquid refers to a liquid containing a solid active material such as a solution (active material liquid), a suspension, or a lump. Examples of the active material liquid include an iron / chromium-based solution and a vanadium-based solution. In order to increase the electrode reactivity, it is important to have affinity with the electrode and high fluidity. In addition, in the case of sulfuric acid acidity, it is necessary to consider viscosity and conductivity. When an acidic vanadium sulfate aqueous solution is used as the active material, increasing the concentration such that the vanadium concentration exceeds 2.5M and the total sulfate radical concentration exceeds 5M can increase the energy density of the active material solution to some extent, but the viscosity increases. In addition, the conductivity tends to decrease and the cell resistance tends to increase.

  The active material liquid (including not only a normal electrolytic solution but also a suspension) may be always circulated (circulated) in the cell or may be circulated intermittently.

  As an example of the configuration of the laminated battery 40, an exterior plate / current collector plate / end plate / electrode integrated (single side) electrode plate / frame / diaphragm / frame / bipolar partition plate / electrode integrated (double side) electrode plate / Diaphragm / Frame / Bipolar divider / electrode integrated (double-sided) electrode plate /.../ Frame / Diaphragm / Frame / End plate / electrode integrated (single side) electrode plate / Frame / End plate Examples include electrode-integrated (single-sided) electrode plates / exterior plates. That is, it has a cell stack structure in which a frame, a diaphragm, and an electrode plate are appropriately laminated. Each component is fused and / or bonded to each other.

  As described above, in the laminated battery according to the embodiment of the present invention, the electrode plate includes the bipolar electrode partition plate, and the bipolar electrode partition plate has a current collecting terminal and can directly input / output from / to the outside of the cell stack. Can be.

  For example, by arranging a large number of cell units of the same standard in series, a secondary battery having an arbitrary voltage and current rating value can be made, and by having an intermediate input / output terminal between adjacent cell units, An efficient secondary battery system capable of input / output can be obtained. In such a secondary battery system, for example, a non-contact switching element and a contact-type change-over switch that can be switched to at least one of the current collecting terminals of a plurality of cells based on the output voltage of the power generator of natural energy The charge acceptability can be improved without using a DC-DC converter or the like by an inexpensive method. By having such a switching mechanism, a stacked battery 40 (secondary battery system) capable of efficient input / output can be obtained.

<3. Electrolyzer>
One embodiment of the present invention is an electrolytic cell 40 having the above-described cell stack, in which the frame, the diaphragm, and the electrode plate as the electrode plate are laminated by adhesion and / or fusion, and the frame. The electrolyte flows through the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided by adhesion and / or fusion.

  The structure of the cell stack used in the electrolytic cell is basically the same as that of the laminated battery. The electrolyte circulates inside, and a chemical is decomposed by applying a voltage through the electrode plate.

  Although the laminated battery and the electrolytic cell are described separately, the cell stack according to the embodiment of the present invention can of course be applied as a chargeable / dischargeable redox flow secondary battery.

<4. Dialysis tank>
One embodiment of the present invention is a dialysis tank having the above-described cell stack, and the cell stack includes a frame body, a diaphragm, and an electrode plate as a current collector plate laminated by adhesion and / or fusion. The solution to be treated or the concentration solution flows through the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided by adhesion and / or fusion. In the dialysis tank according to an embodiment of the present invention, the electrode plates may be provided as end plates (terminal plates) at both ends of the cell stack configuration, and may be provided as a bipolar plate for each unit of a single cell. is there.

  The dialysis tank according to an embodiment of the present invention is applicable as an apparatus for separating and recovering heavy metal components from a solution or suspension liquid to be treated. For example, when the dialysis tank according to one embodiment of the present invention recovers heavy metals from various process waste liquids containing heavy metals such as liquid discharged from a plating process or the like, and makes the heavy metal concentration in the effluent of the water treatment facility lower than the reference value It is possible to apply in a wide range. In particular, when it is necessary to remove heavy metals up to environmental standards, it can be handled by increasing the required treatment area for irrigation water or natural water with low conductivity of the liquid to be treated. Further, when a slurry or sludge such as sewage sludge is used as a target, it can be dealt with by changing the workpiece introduction part and adding an electrodeposition method. Furthermore, since the dialysis tank according to an embodiment of the present invention can easily adjust the residence time, a single-stage processing apparatus can be used in any case.

  FIG. 4 is a perspective view showing an example of the configuration of a dialysis tank to which the cell stack according to one embodiment of the present invention is applied. The dialysis tank 60 according to an embodiment of the present invention has a configuration of a cathode side current collector plate 62 / cathode chamber 63 / diaphragm 64 / treatment liquid introduction chamber 65 / diaphragm 66 / anode chamber 67 / anode side current collector plate 68. Have. The cathode chamber 63, the liquid to be treated introduction chamber 65, and the anode chamber 67 are provided with the inflow slit tube and the outflow slit tube, but it is not necessary to provide a plurality of all the frame bodies. For example, the liquid inlet chamber 65 through which the liquid to be processed flows is provided with only one inflow slit tube and outflow slit tube, and a plurality (in the cathode chamber 63 and the anode chamber 67 through which the concentration solution and the like flow). For example, a configuration in which three inflow slit tubes and outflow slit tubes are provided may be employed.

  In addition, the dialysis tank 60 which concerns on one Embodiment of this invention may laminate | stack a layer further by making the said structure into 1 unit. For example, a configuration such as exterior plate / current collector plate / end plate / frame / diaphragm / frame / diaphragm / frame /.../ frame / diaphragm / frame / end plate / current collector / exterior plate But you can. At this time, the respective components are fused and / or bonded to each other. Further, in the dialysis tank 60 according to one embodiment of the present invention, the electrode plate includes a bipolar electrode partition plate, and the bipolar electrode partition plate has a current collecting terminal so that it can directly input / output from / to the outside of the cell stack. Can be.

  The cathode side current collecting plate 62 is used as a multipolar partition plate in addition to the end cell (end plate), and in any case, an electrode plate for water electrolysis is used. The cathode-side current collecting plate is, for example, a stainless steel or titanium plate coated with a platinum-based noble metal.

  The cathode chambers 61 and 63 are surrounded by a stretchable frame material, and are partitioned on one side by a cathode and the other side by a permeable membrane. The heavy metal that has permeated through the permeable membrane is deposited here as a basic compound. In the dialysis tank 60 according to an embodiment of the present invention, the cathode chamber is compressed after the deposition step to reduce moisture, and can be recovered as heavy metal sludge. When heavy metals such as zinc are electrodeposited on the cathode, after sludge is collected, water is injected, and the polarity is inverted from the cathode to the anode to elute the heavy metals and collect as a concentrated solution.

  The diaphragms 64, 66, and 70 are provided on both surfaces of the treatment liquid introduction chamber, and are used for ion processing when ionized heavy metal is mainly processed and when suspended heavy metal is mainly processed. It is selected whether to use a porous membrane or a microporous membrane.

  A solution for performing dialysis treatment flows through the liquid to be treated introduction chambers 65 and 71. For example, heavy metals and the like are removed from this solution. If the liquid to be treated has a large flow rate, the dialysis treatment may not be sufficiently performed. Therefore, it is preferable that the liquid to be treated be circulated slowly.

  In the anode chambers 67 and 69, heavy metals generally do not easily precipitate, and the permeated heavy metals are concentrated here and collected as a concentrated liquid. Further, the anode side current collector plate 68 has the same structure as the cathode side current collector plate except for the end cell (end plate), and can have the same structure as the cathode side current collector plate.

  In the dialysis tank according to an embodiment of the present invention, for example, the following heavy metals can be targeted.

  Dialysis separation of Cr (III). Since Cr (III) is difficult to electrodeposit as a metal (electrode potential of Cr (II) → Cr (0) to −1.0V, electrode potential of Cr (III) → Cr (II) to −0.4V), dialysis It is separated by the method and concentrated and recovered as a basic precipitate on the cathode chamber side where hydrogen ions are consumed. Although it behaves like iron, it has stronger properties as an amphoteric element than iron, and can be eluted with strong alkalinity and separated from iron (fully dissolved at pH 10 or higher). Cr is similar to iron in that it does not make much ammonia complexes, while it makes some complexes with organic acids such as acetic acid.

  Ni (II) separation, dialysis method and electrodeposition / elution method. Ni (II) is considered to be relatively easily recovered by the dialysis method, but can be electrodeposited by keeping the electrode at the base (Ni (II) → Ni (0) electrode potential to −0.25). V). In this case, it is considered that the elution potential can be adjusted to be separated and recovered from zinc or copper, and separation from Cu that is electrodeposited at a particularly noble potential is easy. On the other hand, Ni is insoluble in strong alkali, but is different from Cr and Fe in that it is easily dissolved by forming an ammonia complex. However, Zn is similar in reactivity to alkalis, complex ligands, sulfide ions, etc., so it is difficult to separate it cheaply by chemical reaction, and a method of separation by changing the electrodeposition / elution potential is preferable.

  Zn (II) can be electrodeposited by keeping the electrode sufficiently base. Furthermore, the elution potential can be adjusted to separate and recover from other metals. (Zn (II) → Zn (0) electrode potential to -0.76V)

  Cu (II) can be easily electrodeposited even when the electrode potential is noble. It is also possible to separate and recover from other electrodeposited heavy metals by adjusting the elution potential. (Cu (II) → Cu (0) electrode potential to + 0.34V, in the presence of a large amount of halide ions, the potential may be negative due to complex formation.)

In addition, there are the following heavy metals as harmful substances.
Pb and Hg can be electrodeposited at a noble potential, and can be separated and recovered by adjusting the elution potential in the same manner as copper.
Cd and As are difficult to recover by electrodeposition, and are generally selectively separated and recovered by electrodialysis.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely using an Example, this invention is not limited to a following example at all.

  Using a 30 mm wide and 20 mm long bipolar electrolytic cell (3-cell stack type) with a 3 mm thick electrode chamber, 3.5 M sulfuric acid 1.5 M vanadium ions (the negative electrode side is vanadium divalent and trivalent, The positive electrode side was subjected to a charge / discharge test of a redox flow secondary battery configured as shown in FIG. 3 using vanadium tetravalent and pentavalent) as an active material liquid.

  Three PVC inflow / outflow tubes were inserted into a foamed polyvinyl chloride resin (PVC) frame and bonded with a solvent (acetone). The electrode chamber surrounded by the PVC frame was filled with carbon fiber felt activated by anodizing so that a space of 2 mm was formed above and below the chamber. The bipolar separator was manufactured by sandwiching a 300 mesh copper mesh between PVC resin sheets kneaded with graphite powder, and the above activated carbon fiber felt was fused and integrated by hot pressing. (Polyolefin cation exchange membrane was used for the diaphragm.)

The active material liquid was fed to the bipolar chambers by a tube pump, and a screw cock was attached in the middle of each of the three active material liquid inflow / outflow pipes so that the number of the active material liquids could be determined arbitrarily.
The number of stacked cells was 3 cells.

When the electrolyte solution is introduced into the electrode chamber with a single slit tube, the sheet feed rate, the feed pressure (pump discharge pressure), and the charge / discharge 1A charge / discharge (approximately 170 mA / cm ² charge / discharge) area resistivity ( [Voltage difference of charge / discharge] / [current density × 2]). The results are as follows.

  From the results in Table 1, a charge / discharge test was conducted when the amount of electrolyte introduced into the electrode chamber was 10 ml / min, and one, two, and three slit tubes were used. The liquid feeding pressure and the sheet resistivity of charge / discharge 1A charge / discharge were as follows.

  As can be seen from the results in Table 2, the stack cell having a plurality of slit tubes according to an embodiment of the present invention has a half area resistivity as compared with the case of a single slit tube as in the conventional comparative example 1. It turns out that it can reduce to the following.

  Although the embodiments and examples of the present invention have been described in detail as described above, it will be understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. It will be easy to understand. Therefore, all such modifications are included in the scope of the present invention.

  For example, a term described with a different term having a broader meaning or the same meaning at least once in the specification or the drawings can be replaced with the different term in any part of the specification or the drawings. Further, the configurations and operations of the cell stack, the laminated battery, the electrolytic cell, and the dialysis tank are not limited to those described in the embodiments and examples of the present invention, and various modifications can be made.

  The cell stack according to the present invention can also be applied to a redox secondary battery, and is provided as a power supply system by electrically connecting a solar battery or a wind power generator to a redox secondary battery system via a switch element. You can also The cell stack according to an embodiment of the present invention, as a dialysis tank, recovers heavy metals from various process waste liquids containing heavy metals such as liquids discharged from plating processes, etc., and reduces the heavy metal concentration in the water discharged from the water treatment facility to a reference value or less. It is possible to apply in a wide range.

10 Cell stack, 11, 21, 31, 41, 43, 45, 47, 49 Frame, 12 (12A, 12B, 12C), 22 (22A, 22B, 22C), 32 (32A, 32B, 32C) Inflow slit Tube, 13 (13A, 13B, 13C), 23 (23A, 23B, 23C), 33 (33A, 33B, 33C) Outflow slit tube, 14, 44, 48, 64, 66 Diaphragm, 15, 42, 46, 50 Electrode plate, 16 Current collecting terminal, 30 Cell unit, 34 Electrode, 35 (35A, 35B, 35C) Inflow side on / off valve, 36 (36A, 36B, 36C) Outflow side on / off valve, 37 Inflow manifold, 38 For outflow Manifold, 40 Stacked battery, 40 Electrolyzer, 51 End plate, 60 Dialysis tank, 61 Cathode chamber, 62 Cathode side current collector plate, 63 Cathode chamber, 65 Cover Physical fluid introduction chamber, 67 an anode compartment, 68 anode side collector plate

Claims (10)

A cell stack that is applied to a laminated battery, an electrolyzer, or a dialysis tank and is filled with a solution,
At least one or more frames;
An inflow slit tube for allowing the solution to flow into the inside through the frame,
An outflow slit tube that allows the solution to flow out to the outside through the frame;
A diaphragm separating the solution in the frame;
Comprising an electrode plate separating a part of the frame,
The frame is made of closed cell resin,
A cell stack comprising a plurality of the inflow slit tubes and the outflow slit tubes for at least one frame.   The sum of the cross-sectional areas in the inflow slit tube or the outflow slit tube is 5% or more and 30% or less of the cross-sectional area of a plane perpendicular to the direction in which the solution flows in the frame. The cell stack according to claim 1.   The cell stack according to claim 1 or 2, wherein the frame is made of a resin containing polyvinyl chloride and / or polyvinylidene chloride.   4. A solution permeable electrode is provided inside the frame, and the permeation resistance of the solution in the electrode is 10 times or more of the permeation resistance of the inflow slit tube or the outflow slit tube. The cell stack according to any one of the above. A laminated battery having the cell stack according to any one of claims 1 to 4,
The cell stack is formed by laminating a frame, a diaphragm, and an electrode plate as an electrode plate by adhesion and / or fusion, and a plurality of the inflow slit tubes provided by adhesion and / or fusion to the frame. An active material liquid flows through the cell stack through an outflow slit tube.   6. The laminated battery according to claim 5, wherein the electrode plate includes a multi-polar partition plate, and the multi-pole partition plate has a current collecting terminal and can directly input / output from / to the outside of the cell stack. An electrolytic cell having the cell stack according to any one of claims 1 to 4,
The cell stack is formed by laminating a frame, a diaphragm, and an electrode plate as an electrode plate by adhesion and / or fusion, and a plurality of the inflow slit tubes provided by adhesion and / or fusion to the frame. An electrolytic cell characterized in that an electrolyte flows through the cell stack through an outflow slit tube.   The electrolytic cell according to claim 7, wherein the electrode plate includes a multi-electrode partition plate, the multi-electrode partition plate has a current collecting terminal, and can directly input / output from / to the outside of the cell stack. A dialysis tank having the cell stack according to any one of claims 1 to 3,
The cell stack includes a plurality of inflow slit tubes provided by laminating and / or fusing a frame, a diaphragm, and an electrode plate as a current collector plate, and bonding and / or fusing to the frame. A dialysis tank, wherein a liquid to be treated or a concentration solution flows through the cell stack through the outflow slit tube.   The dialysis tank according to claim 9, wherein the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a current collecting terminal and can directly input / output from / to the outside of the cell stack.

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