JP6807626B2 - Cell stack, laminated battery, electrolytic cell, and dialysis tank - Google Patents

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 laminated has been proposed and prototyped for application to a laminated battery, an electrolytic cell, a dialysis tank, and the like.

For example, Patent Document 1 describes a cell stack for a redox flow battery in which a cell frame, an electrode, and a diaphragm are laminated. The cell frame includes a frame frame and a bipolar plate integrated with the frame frame, and is an electrode. Describes a cell stack for a redox flow battery, characterized in that it is brought into close contact with the bipolar plate by a tightening force without being adhered 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 a waste liquid portion are usually provided at the end of the rectangular electrode chamber. It is provided.

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

JP-A-2002-376660 Japanese Unexamined Patent Publication No. 2-183968

In such a cell stack, it is necessary to increase the number of stacked unit cells (cell units) in order to realize high capacity and large scale. However, as the number of stacks increases, the weight and cost of the entire cell stack become a problem.

Further, regarding the means for sending the solution into the cell stack, a method in which a slit for guiding the electrolytic solution from the manifold to each electrode chamber is formed into a tube shape and communicated with a manifold provided outside the cell stack is also a method in which the slit is long and electric It was carried out to increase the resistance and reduce the leakage current value flowing through the manifold.

However, increasing the thickness of the electrode chamber and increasing the diameter of the slit tube to secure a sufficient amount of liquid to be fed is not practical because it increases the internal resistance of the cell. Here, it is possible to increase the liquid feed pressure to increase the flow rate, 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 a pump.

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

The present invention has been made in view of the above problems, and is a cell stack capable of realizing weight reduction and cost reduction, suppressing slit flow resistance and leakage current, and efficiently sending a solution to the inside. An object of the present invention is to provide a laminated battery, an electrolytic cell, and a dialysis tank having the cell stack.

One aspect of the present invention is a cell stack that is applied to a laminated battery, an electrolytic cell, or a dialysis tank and is filled with a solution, and at least one frame and a solution that penetrates the frame and is inside. It is provided with an inflow slit tube for inflow, an outflow slit tube for allowing the solution to flow out through the frame, a diaphragm for separating the solution in the frame, and a electrode plate for separating a part of the frame, and the frame is independent. is constituted by a bubble resin, inlet slots pipe and the outlet slit tube plurality equipped et is for at least one frame, the total cross-sectional area of the inlet slit tube or outlet slits tract, in the direction in which a solution of the frame body flows On the other hand, it is 5% or more and 30% or less of the cross-sectional area of the vertical surface .

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, the slit flow resistance and the leakage current can be suppressed, and the solution can be efficiently sent to the cell stack.

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 from the viewpoint of efficiently delivering the solution to the cell stack.

Further, in one aspect 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 suitable for laminating because of their excellent adhesiveness and fusion property.

Further, in one aspect of the present invention, the solution permeation type 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 ratio of transmission resistance is within the above numerical range, the solution can be efficiently sent to the cell stack.

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

In this way, if the laminated battery is constructed by using the cell stack structure described above, the weight and cost of the laminated battery can be reduced, and the slit flow resistance and the leakage current can be suppressed to form the laminated battery. The active material liquid can be efficiently sent 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 terminal for collecting current so that it can directly input / output to and from the outside of the cell stack. Good.

By having an intermediate input / output terminal between the stacked single battery units in this way, it is possible to obtain a laminated battery capable of efficient input / output.

In addition, another aspect of the present invention is an electrolytic cell having the above-mentioned cell stack, in which the frame body, the diaphragm, and the electrode plate as the electrode plate are laminated by adhesion and / or fusion, and the frame is formed. The electrolytic solution flows through the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided on the body by adhesion and / or fusion.

In this way, if the electrolytic cell is constructed using the cell stack structure described above, the weight and cost of the electrolytic cell can be reduced, and the slit flow resistance and leakage current can be suppressed to form the electrolytic cell. The electrolytic solution can be efficiently sent 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 terminal for collecting current so that it can directly input / output to and from the outside of the cell stack. Good.

By having the intermediate input / output terminals between the stacked electrolytic cell units in this way, it is possible to obtain an electrolytic cell capable of efficient input / output.

In addition, another aspect of the present invention is a dialysis tank having the above-mentioned cell stack, in which the frame body, the diaphragm, and the electrode plate as the current collector plate are laminated by adhesion and / or fusion. The liquid to be treated or the solution for concentration flows through the cell stack through a plurality of inflow slit tubes and outflow slit tubes provided on the frame by adhesion and / or fusion.

In this way, if the dialysis tank is constructed using the cell stack structure described above, the weight and cost of the dialysis tank can be reduced, and the slit flow resistance and leakage current can be suppressed to form the dialysis tank. The solution can be efficiently sent 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 terminal for collecting current so that it can directly input / output to and from the outside of the cell stack. Good.

By having an intermediate input / output terminal between the stacked dialysis tank units in this way, an efficient dialysis tank can be obtained.

As described above, according to the present invention, it is possible to realize weight reduction and cost reduction of the entire cell stack, and to suppress slit flow resistance and leakage current to maintain good equal distribution of liquid to the cell stack. ..

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

Hereinafter, preferred embodiments of the present invention will be described in detail in the following order with reference to the drawings. It should be noted that the present embodiment described below does not unreasonably limit the content of the present invention described in the claims, and all the configurations described in the present embodiment are essential as a means for solving the present invention. Is not always the case.
1. 1. Cell stack 1-1. Frame 1-2. Inflow slit pipe and outflow slit pipe 1-3. Septum 1-4. Plate 1-5. Electrode 2. Laminated battery 3. Electrolytic cell 4. Dialysis tank

<1. Cell stack>
FIG. 1 shows an exploded perspective view showing an example of a configuration of a cell stack according to an embodiment of the present invention. Further, FIG. 2 is a diagram showing an example of a partial configuration of a cell stack according to an 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 has at least one or more frames 11, 21 and frames 11, 21. The inflow slit tubes 12 and 22 that penetrate the frame and allow the solution to flow into the inside, the outflow slit tubes 13 and 23 that penetrate the frame and allow the solution to flow out to the outside, the diaphragm 14 that separates the solution in the frame, and the frame. A electrode plate 15 that separates 21 is provided, the frame bodies 11 and 21 are made of closed cell resin, and a plurality of inflow slit tubes 12 and 22 and outflow slit tubes 13 and 23 are provided for at least one frame body 11 and 21. It is characterized by being.

In this way, by forming the frames 11 and 21 with the closed cell resin, weight reduction and cost reduction are realized, and the inflow slit pipes 12 and 22 and the outflow slit tubes 13 and 23 are at least one frame 11, 21. By providing a plurality of the solutions, the slit flow resistance and the leakage current can be suppressed, and the solution can be efficiently sent to the cell stack 10. Hereinafter, the components of the cell stack 10 according to the 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)
The frames 11 and 21 used in the cell stack 10 according to the embodiment of the present invention are made of closed cell resin. The closed cells are those in which air-containing bubbles are not connected, and thus it is possible to prevent the solution from permeating through the resin. Further, since such a closed cell resin is lightweight, the total weight can be suppressed even when a large number of a plurality of cell units are laminated as in the cell stack 10.

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 laminating because they are excellent in adhesiveness and adhesiveness.

The frames 11 and 21 are partitioned by a diaphragm 14 and a electrode plate 15, which will be described later, depending on the intended use. 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 a electrode plate 15. It should be noted that the configuration of FIG. 1 shows a part of the cell stack, and in reality, a cell stack composed of a large number of layers can be configured by being stacked in such an order. At this time, it is preferable that the plurality of frame bodies 11 and 21 are laminated by adhesion or fusion through the diaphragm 14 or the electrode plate 15. By integrating the frame bodies 11 and 21 with the diaphragm 14 and the electrode plate 15 by adhesion or heat fusion, the force of holding the cell stack 10 with bolts or the like is reduced when the number of stacked cells increases. This can reduce the weight of the entire cell stack 10.

Further, since the frame bodies 11 and 21 are formed of the closed cell resin, the frame bodies 11 and 21 may be configured to be compressed in the thickness direction and thinned by the pressurization at the time of laminating. By doing so, it is possible to realize thinning of the entire cell stack 10. When the frame bodies 11 and 21 are thinned by pressurization, the inflow slit pipe, the outflow slit pipe, the electrodes, etc. provided in the frame bodies 11 and 21 consider the thinning of the frame bodies 11 and 21. It is desirable to put it in the design.

When the cell stack 10 according to the embodiment of the present invention is used for 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. Can be configured as follows. At this time, it is preferable that each electrode plate 15 is in contact with the electrode 34 of the adjacent frame body, and the electrode plate 15 is provided with a current collecting terminal 16. Then, by adjusting the number of cells stacked in series as described later, the function of the DC-DC converter can be provided.

(1-2. Inflow slit pipe and outflow slit pipe)
Inflow slit pipes 12 (12A, 12B, 12C), 22 (22A, 22B, 22C) and outflow slit pipes 13 (13A), which are slit-shaped pipes for circulating the solution, are provided in the cell stack frames 11 and 21. , 13B, 13C), 23 (23A, 23B, 23C) are provided. For the inflow slit pipes 12 and 22 and the outflow slit pipes 13 and 23, for example, those made of polyvinyl chloride (PVC) are used, and are adhered to or fused to the frames 11 and 21 with a solvent (for example, acetone) or the like. It is preferable to be worn. As a result, the slit flow resistance and the leakage current from the slit can be suppressed.

The total cross-sectional area of the plurality of inflow slit pipes 12 and 22 or the outflow slit pipes 13 and 23 is 5% or more of the cross-sectional area of the plane perpendicular to the direction in which the solution flows in the frames 11 and 21. It is preferably 30% or less. It is desirable that the ratio of the cross-sectional area of the slit tube is within this numerical range in order to efficiently feed the solution to the cell stack. For example, when a frame having a thickness of 3 mm, a width of 30 mm, and a height of 20 mm is used inside and a slit tube having an inner diameter of 1.5 mm is provided perpendicular to the width direction, the cross-sectional area of each 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. If the ratio of the cross-sectional area is less than 5%, the flow resistance in the slit becomes too high. Further, when the ratio of the cross-sectional area exceeds 30%, the leakage current flowing through the slit tube and the manifold increases too much, which is not efficient.

The inflow slit pipe 32 (32A, 32B, 32C) and / or the outflow slit pipe 33 (33A, 33B, 33C) has, for example, an inflow manifold 37 and / or an outflow manifold 38 attached to the outside as shown in FIG. It is preferable that it is. By doing so, the loss due to the leakage current can be reduced, and the solution can be efficiently sent into the frame of the cell stack. Further, by providing the inflow side on-off valve 35 (35A, 35B, 35C) and / or the outflow side on-off valve 36 (36A, 36B, 36C) in the plurality of inflow slit pipes 32 and / or the outflow slit pipes 33, It is preferable to be able to adjust the number of slit tubes to be used according to the situation. In FIG. 2, the inflow slit pipe 32 and / or the outflow slit pipe 33 is 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 permeation type 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. This makes it possible to easily realize the equidistant distribution of the solution in the cell.

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

(1-3. Septum)
The diaphragm 14 is mainly a proton-anion exchange membrane having high proton conductivity. For example, fluororesin-based (Nafion (registered trademark) 117, 211, etc.), polystyrene sulfonic acid-based, polyolefin-based, and other ion exchange membranes are used. As the porous membrane, a precision filtration membrane (MF) is used. There are examples of use such as an outer filter membrane (UF) and a nanofilter membrane (NF). The volume resistance of the iron / chromium-based active material solution is about 1 Ωcm, which is close to that of hydrochloric acid, but polystyrene-acidic vanadium is used as the active material. In this case, the resistance is several times higher than this, and it is necessary to give due consideration to the ion exchange capacity and thickness of the diaphragm.

(1-4. Plate)
In the cell stack 10 according to the embodiment of the present invention, in order to optimize the input / output (voltage) by using many intermediate input / output terminals (trim cell terminals), the electrode plate 15 (multi-pole partition plate, bipolar plate) ) 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. By doing so, the internal resistance (cell area resistivity) is reduced, and by having the current collecting terminal 16 at one end of the electrode plate 15, consideration is given to creating a uniform potential distribution over the entire surface of the electrode plate 15. You don't need it anymore.

As an example of the electrode plate 15 (bipolar plate), a carbon plastic sheet / a copper sheet having a current collecting terminal / a carbon plastic sheet, or a copper mesh / a carbon plastic sheet is preferable. In the case of a multi-pole partition plate (bipolar plate) in which electrodes are in contact with both sides of the electrode plate 15, it is necessary to sandwich both sides of the metal sheet with conductive resin sheets, but only one side of the cell stack 10 has electrodes. In the case of a unipolar 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 preferably 0.01 Ωcm or less, preferably 0.005 Ωcm or less, and more preferably 0.001 Ωcm or less. It is important to reduce the volume resistivity in the overall length direction in order to carry out a uniform charge / discharge reaction on the electrode surface and to maintain high voltage efficiency. However, in order to obtain a uniform potential distribution, such a 0.01 Ωcm electrode plate needs to have a thickness of 3 to 5 mm or more, and a thickness of about 1 mm to 2 mm for a small cell stack 10. In order to realize the production, it is preferable that the average volume resistivity is 0.005 Ωcm to 0.0005 Ωcm or less. For this purpose, it is necessary to make a plate with a metal sheet or mesh having high conductivity sandwiched between them.

Further, it is preferable that the carbon plastic sheet uses a thermoplastic resin such as polyethylene or polypropylene as the resin and is integrated with the conductive carbon fiber non-woven fabric which is an electrode by means such as heat welding and welding with a solvent. The resin of the carbon plastic sheet suitable for heat welding is a polyolefin resin or the like, and the resin suitable for welding is polyvinyl chloride or the like. As a result, the contact resistance between the electrode and the plate can be minimized. The contact resistance between the case of fusion and the case of no fusion has a difference of about 0.01Ωcm ² and 0.10Ωcm ² in area resistivity, respectively.

(1-5. Electrode)
When the cell stack according to the embodiment of the present invention is used for a laminated battery or an electrolytic cell, it has an electrode 34 in a frame 31 as shown in FIG. The electrode 34 is a porous conductor through which an active material liquid is circulated and impregnated, and the material is a metal such as carbon or lead. The electrode 34 is, for example, a carbon fiber felt (carbon fiber electrode). Further, it is preferable that the presence of carbon fibers constituting the carbon fiber electrode having a fiber diameter of 5 μm or less can be confirmed by microscopic observation (for example, scanning electron microscope (SEM)) from the viewpoint of active material catching property.

The fiber diameter of conventional polyacrylonitrile (PAN), cellulose, pitch, quinol, etc. is in the range of about 7 to 12 μm, and as observed by SEM, there are usually no fibers having a diameter of 5 μm or less. 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, which enables electrolysis by high-dimensional diffusion, and when used as a collecting electrode, it has a high current density (for example, stationary) even in an active material liquid stationary system. Even in the system, 100 mAcm- ² ) can be obtained. Further, the carbon fiber electrode having a reduced fiber diameter can also be obtained by electrolytic oxidation treatment or the like. In this way, by using the carbon fiber electrode having a reduced fiber diameter as the electrode 34, the output density in the battery body (electrolytic cell) is increased, and the battery is downsized (in some cases, the size is 1/2 or less). , It becomes possible to greatly reduce the manufacturing cost. If the fiber diameter is actually set to about 5 μm or less, the mass transfer can be improved, and the flow type can have a current density of several hundred mAcm- ² .

Further, the carbon fiber felt may be electrolytically oxidized in dilute sulfuric acid or the like. Thus, the fiber diameter becomes smaller, the surface is subjected to significantly oxide etch, increase the specific surface area is 1 to 2 orders of magnitude (e.g., 10 to 100 m from ^{1 m} 2 / g approximately as a BET specific surface area by nitrogen gas ² / Increase to g). At the same time, an oxygen element is introduced into the surface as a carbonyl group, a carboxyl group, etc. (for example, the O / C ratio of ESCA is about 0.1% to 1 to 5%) to increase the electron transfer reaction rate in the charge / discharge reaction. , Gas generation, which is a side reaction, can be suppressed by improving the overvoltage. Further, the degree of graphitization may be improved by firing at a temperature of 2000 ° C. to 2500 ° C.

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% as compared with the battery of the conventional electrode. Will be able to.

<2. Laminated battery ＞
One embodiment of the present invention is a laminated battery having the cell stack described above. In the cell stack, a frame body, a diaphragm, and an electrode plate as an electrode plate are laminated by adhesion and / or fusion, and the cell stack is formed on the frame body. The active material liquid flows through 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 the configuration of a laminated battery to which the cell stack according to the embodiment of the present invention is applied or an electrolytic cell described later. The laminated battery 40 according to the embodiment of the present invention is ... / Frame 41 / Electrode 42 / Frame 43 / Septum 44 / Frame 45 / Electrode 46 / Frame 47 / Septum 48 / Frame 49 It has a structure in which a frame, a diaphragm, and an electrode plate as an electrode plate are laminated as a cell stack, such as / diaphragm 50 / end plate 51, and each frame has an electrode inside.

In the laminated battery 40, the solution to be distributed is an active material solution. 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 solution include iron / chromium-based solutions and vanadium-based solutions. In order to increase the electrode reactivity, it is important that the electrode has an affinity with the electrode and that the fluidity is high. In the case of sulfuric acid acidity, it is necessary to consider the viscosity and conductivity. When an aqueous solution of acidic vanadium sulfate is used as an active material, a high concentration such that the vanadium concentration exceeds 2.5 M and the total sulfate root concentration exceeds 5 M can increase the energy density of the active material solution to some extent, but increases the viscosity. In addition, the conductivity tends to decrease and the cell resistance tends to increase.

The active material solution (including not only a normal electrolytic solution but also a suspension) may be constantly 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-sided) electrode plate / frame / diaphragm / frame / multi-pole partition plate / electrode integrated (double-sided) electrode plate / Diaphragm / frame / multi-pole partition plate / electrode integrated (both sides) electrode plate / ・ ・ ・ / frame / diaphragm / frame / end plate / electrode integrated (single sided) electrode plate / frame / end plate ・Electrode integrated (single-sided) Electrode plate / exterior plate-like configuration can be mentioned. That is, it has a cell stack structure in which a frame body, a diaphragm, and an electrode plate are appropriately laminated. The components are fused and / or glued to each other.

As described above, in the laminated battery according to the embodiment of the present invention, the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a terminal for current collection and can directly input / output to the outside of the cell stack. Can be done.

For example, by arranging a large number of cell units of the same standard in series, it is possible to make a secondary battery with an arbitrary voltage and current rating value, and by having an intermediate input / output terminal between adjacent cell cell units, It can be a secondary battery system capable of efficient input / output. In such a secondary battery system, for example, a contactless switching element and a contact type switching switch that can switch to at least one of the current collecting terminals of a plurality of cells based on the output voltage of a natural energy power generation device. It is possible to improve the charge acceptability by an inexpensive method without using a DC-DC converter or the like. By having such a switching mechanism, it is possible to obtain a laminated battery 40 (secondary battery system) capable of efficient input / output.

<3. Electrolytic cell ＞
One embodiment of the present invention is an electrolytic cell 40 having the above-mentioned cell stack. In the cell stack, a frame body, a diaphragm, and an electrode plate as an electrode plate are laminated by adhesion and / or fusion, and the frame body is formed. The electrolytic solution 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 electrolytic solution circulates inside, and a voltage is applied through the electrode plate to perform chemical decomposition.

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 rechargeable redox flow secondary battery.

<4. Dialysis tank ＞
One embodiment of the present invention is a dialysis tank having the above-mentioned cell stack. In the cell stack, a frame body, a diaphragm, and a electrode plate as a current collecting plate are laminated by adhesion and / or fusion, and the frame body is formed. The liquid to be treated or the solution for concentration 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 the embodiment of the present invention, the electrode plates may be provided as end plates (terminal plates) at both ends of the cell stack configuration, or may be provided as a multi-pole partition plate for each single cell unit. is there.

The dialysis tank according to the embodiment of the present invention can be applied as an apparatus for separating and recovering heavy metal components from a solution or suspension liquid to be treated. For example, in the dialysis tank according to the embodiment of the present invention, heavy metal recovery from various process waste liquids containing heavy metals such as liquid discharged from a plating process, and heavy metal concentration in water discharged from a water treatment facility are set to a reference value or less. It can be applied in a wide range. Especially when it is necessary to remove heavy metals up to the environmental standard, it can be dealt with by increasing the required treatment area for irrigation water or natural water with low conductivity of the liquid to be treated. Further, when targeting a slurry or sludge such as sewage sludge, it can be dealt with by changing the introduction portion of the object to be treated and adding an electrodeposition method. Further, since the dialysis tank according to the embodiment of the present invention can easily adjust the residence time, any case can be dealt with by the one-stage treatment apparatus.

FIG. 4 is a perspective view showing an example of the configuration of a dialysis tank to which the cell stack according to the embodiment of the present invention is applied. The dialysis tank 60 according to the embodiment of the present invention has a configuration such as a cathode side current collector plate 62 / cathode chamber 63 / diaphragm 64 / liquid introduction chamber 65 / diaphragm 66 / anode chamber 67 / anode side current collector plate 68. Have. The cathode chamber 63, the liquid to be introduced chamber 65, and the anode chamber 67 are provided with an inflow slit pipe and an outflow slit pipe, but not all of the frames may be provided with a plurality of the inflow slit pipe and the outflow slit pipe. For example, the liquid to be introduced chamber 65 through which the liquid to be treated flows is provided with only one inflow slit tube and the outflow slit pipe, and the cathode chamber 63 and the anode chamber 67 through which the solution for concentration and the like flow are provided with a plurality of ( For example, the configuration may be such that three) inflow slit pipes and outflow slit pipes are provided.

The dialysis tank 60 according to the embodiment of the present invention may be further laminated with the above configuration as one unit. For example, exterior plate / current collector plate / end plate / frame body / diaphragm / frame body / diaphragm / frame body / ... / frame body / diaphragm / frame body / end plate / current collector plate / exterior plate It may be. At this time, the components are fused and / or bonded to each other. Further, in the dialysis tank 60 according to the embodiment of the present invention, the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a terminal for collecting current so that it can directly input / output to the outside of the cell stack. Can be.

The cathode side current collector plate 62 is used as a multi-pole partition plate other than the end cell (end plate), but in either case, an electrode plate for water electrolysis is used. The cathode side current collector plate is, for example, a stainless steel or titanium plate coated with a platinum-based precious metal.

The cathode chambers 61 and 63 are surrounded by an elastic frame material, and one side is separated by a cathode and the other side by a permeable membrane. The heavy metal that has permeated the permeable membrane is precipitated here as a basic compound. In the dialysis tank 60 according to the embodiment of the present invention, the cathode chamber is compressed after the precipitation step to reduce the water content, and the sludge can be recovered as heavy metal sludge. When a heavy metal such as zinc is electrodeposited on the cathode, sludge is collected, water is injected, the polarity is reversed from the cathode to the anode, and the heavy metal is eluted and recovered as a concentrated solution.

The diaphragms 64, 66, and 70 are located on both sides of the liquid introduction chamber to be treated, and ionize permeation depending on whether the ionized heavy metal is mainly treated or the suspended heavy metal is mainly treated. Select whether to use a sexual diaphragm or a microporous diaphragm.

Solutions for performing dialysis treatment flow through the liquid to be introduced chambers 65 and 71. For example, heavy metals and the like are removed from this solution. If the flow rate of the liquid to be treated is large, the dialysis treatment may not be sufficiently performed. Therefore, it is preferable to distribute the liquid to be treated slowly.

In the anode chambers 67 and 69, heavy metals are generally difficult to precipitate, and the permeated heavy metals are concentrated here and recovered as a concentrated liquid. Further, the anode-side current collector plate 68 has a multi-pole partition plate structure other than the end cell (end plate) like the cathode-side current collector plate, and the same one as the cathode-side current collector plate can be used.

In the dialysis tank according to the embodiment of the present invention, for example, heavy metals such as those listed below can be targeted.

Separation of Cr (III) by dialysis. Cr (III) is difficult to electrodeposit as a metal (Cr (II) → Cr (0) electrode potential ~ −1.0V, Cr (III) → Cr (II) electrode potential ~ −0.4V), so 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 (sufficiently dissolved at pH 10 or higher). Cr is similar to iron in that it does not form much ammonia complexes, while it does form some complexes with organic acids such as acetic acid.

Separation of Ni (II), dialysis method and electrodeposition / elution method. It is thought that Ni (II) can be recovered relatively easily by the dialysis method, but electrodeposition is also possible by keeping the electrodes low (Ni (II) → Ni (0) electrode potential ~ -0.25. V). In this case, it is considered that the elution potential can be adjusted to separate and recover from zinc and copper, and separation from Cu, which is electrodeposited at a noble potential, is particularly easy. On the other hand, Ni is insoluble in strong alkali, but differs from Cr and Fe in that it forms an ammonia complex and is easily dissolved. However, since it is similar to Zn in reactivity with alkali, complex ligand, sulfide ion, etc., it is difficult to separate it inexpensively by a chemical reaction, and a method of separating by changing the electrodeposition / elution potential is preferable.

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

Cu (II) can be easily electrodeposited even if the electrode potential is noble. It is also possible to adjust the elution potential to separate and recover from other electrodeposited heavy metals. (Cu (II) → Cu (0) electrode potential ~ + 0.34V, in the presence of a large amount of halide ions, the potential may become 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 an electrodialysis method.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

Using a multi-pole electrolytic cell (3-cell laminated type) with a width of 30 mm and a length of 20 mm, which has an electrode chamber with a thickness of 3 mm, 3.5 M sulfate-acidic 1.5 M vanadium ion (vanadium divalent and trivalent on the negative electrode side, A charge / discharge test of a redox flow secondary battery having a configuration as shown in FIG. 3 using vanadium tetravalent and pentavalent) as an active material solution was performed on the positive electrode side.

Three PVC inflow / outflow tubes were inserted into the frame made of foamed polyvinyl chloride resin (PVC), and three PVC inflow / outflow tubes were inserted into the frame and adhered with a solvent (acetone). The electrode chamber surrounded by the PVC frame was filled with carbon fiber felt activated by anodizing, so that gaps of 2 mm were formed above and below the chamber. The multi-pole partition plate was manufactured by sandwiching a 300 mesh copper net between PVC resin sheets kneaded with graphite powder, and further fused and integrated the above-mentioned activated carbon fiber felt by hot pressing. (A polyolefin-based cation exchange membrane was used for the diaphragm.)

The active material liquid was sent to both polar chambers by a tube pump, and a screw cock was attached in the middle of the active material liquid inflow and outflow pipes, each of which had three in each chamber, so that the number could be arbitrarily determined.
The number of stacked cells was set to 3.

Area resistivity of liquid feed amount, liquid feed pressure (pump discharge pressure) and charge / discharge 1A charge / discharge (about 170 mA / cm ² charge / discharge) when the electrolyte is introduced into the electrode chamber with a single slit tube. [Charge / discharge voltage difference] / [Current density x 2]) was determined. The results are as follows.

From the results in Table 1, a charge / discharge test was performed when the amount of the electrolytic solution introduced into the electrode chamber was 10 ml / min and the number of slit tubes was 1, 2, and 3. The area resistivity of the liquid feed pressure and charge / discharge 1A charge / discharge was as follows.

As can be seen from the results in Table 2, the stack cell having a plurality of slit tubes according to the embodiment of the present invention has half the area resistivity as compared with the case of one slit tube as in the conventional Comparative Example 1. It can be seen that it can be reduced as follows.

Although each embodiment and each embodiment of the present invention have been described in detail as described above, those skilled in the art can understand that many modifications that do not substantially deviate from the novel matters and effects of the present invention are possible. , Will be easy to understand. Therefore, all such modifications are included in the scope of the present invention.

For example, a term described at least once in a specification or drawing with a different term in a broader or synonymous manner may be replaced by that different term anywhere in the specification or drawing. Further, the configuration and operation of the cell stack, the laminated battery, the electrolytic cell, and the dialysis tank are not limited to those described in each embodiment and each embodiment of the present invention, and various modifications can be carried out.

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 cell or a wind power generator to the redox secondary battery system via a switch element. You can also do it. As a dialysis tank, the cell stack according to the embodiment of the present invention recovers heavy metals from various process waste liquids containing heavy metals such as liquid discharged from a plating process, and reduces the concentration of heavy metals in water discharged from a water treatment facility to a reference value or less. It can be applied in a wide range, such as when

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 Plate, 16 current collecting terminals, 30 cell unit, 34 electrodes, 35 (35A, 35B, 35C) inflow side on-off valve, 36 (36A, 36B, 36C) outflow side on-off valve, 37 inflow manifold, 38 outflow Manifold, 40 laminated battery, 40 electrolytic cell, 51 end plate, 60 dialysis tank, 61 cathode chamber, 62 cathode side current collector, 63 cathode chamber, 65 treatment liquid introduction chamber, 67 anode chamber, 68 anode side current collector

Claims (9)

A cell stack that is applied to a laminated battery, an electrolytic cell, or a dialysis tank and is filled with a solution.
At least one or more frames and
An inflow slit tube that penetrates the frame and allows the solution to flow into the inside,
An outflow slit tube that penetrates the frame and allows the solution to flow out to the outside,
The diaphragm that separates the solution in the frame and
A plate that separates a part of the frame is provided.
The frame is made of closed cell resin.
The inlet slit tube and the outlet slit tube plurality equipped et been for at least one frame,
The total cross-sectional area of the inflow slit pipe or the outflow slit pipe is 5% or more and 30% or less of the cross-sectional area of the plane perpendicular to the direction in which the solution flows in the frame. Cell stack. The cell stack according to claim 1 , wherein the frame is made of a resin containing polyvinyl chloride and / or polyvinylidene chloride. Claim 1 or claim 2 is characterized in that a solution permeation type 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. The cell stack described in. A laminated battery having the cell stack according to any one of claims 1 to 3 .
In the cell stack, a frame body, a diaphragm, and an electrode plate as an electrode plate are laminated by adhesion and / or fusion, and a plurality of the inflow slit tubes provided on the frame body by adhesion and / or fusion and the said A laminated battery characterized in that an active material liquid flows through the cell stack through an outflow slit tube. The laminated battery according to claim 4 , wherein the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a terminal for collecting current and can directly input / output to and from the outside of the cell stack. An electrolytic cell having the cell stack according to any one of claims 1 to 3 .
In the cell stack, a frame body, a diaphragm, and an electrode plate as an electrode plate are laminated by adhesion and / or fusion, and a plurality of the inflow slit tubes provided on the frame body by adhesion and / or fusion and the said An electrolytic cell characterized in that an electrolytic solution flows through the cell stack through an outflow slit tube. The electrolytic cell according to claim 6 , wherein the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a terminal for collecting current and can directly input / output to and from the outside of the cell stack. A dialysis tank having the cell stack according to any one of claims 1 to 3.
In the cell stack, a frame body, a diaphragm, and a electrode plate as a current collecting plate are laminated by adhesion and / or fusion, and a plurality of the inflow slit tubes and the inflow slit tubes provided on the frame body by adhesion and / or fusion. A dialysis tank characterized in that a solution to be treated or a solution for concentration flows through the cell stack through the outflow slit tube. The dialysis tank according to claim 8 , wherein the electrode plate includes a multi-pole partition plate, and the multi-pole partition plate has a terminal for collecting current and can directly input / output to and from the outside of the cell stack.

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