JP2018037290A - Flow battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow battery arranged so that the electrical conduction of a negative electrode and a positive electrode can be suppressed.SOLUTION: A flow battery according to an embodiment hereof comprises: a first electrode; a second electrode; a reaction chamber; an electrolyte solution; and a bubble-generating device. The reaction chamber has a first restriction part on its inner face for restricting the displacement of the first electrode, and contains the first and second electrodes. The electrolyte solution is contained in the reaction chamber, and put in contact with the first and second electrodes. The bubble-generating device supplies gas into the electrolyte solution to generate bubbles.SELECTED DRAWING: Figure 1

Description

  The disclosed embodiments relate to flow batteries.

Conventionally, a flow battery in which an electrolytic solution containing tetrahydroxyzincate ions ([Zn (OH) ₄ ] ²⁻ ) is circulated between a positive electrode and a negative electrode is known (see, for example, Non-Patent Document 1). .

  In addition, a technique has been proposed in which dendrite growth is suppressed by covering a negative electrode containing an active material such as zinc species with an ion conductive layer having selective ion conductivity (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2015-185259

Y. Ito. Et al .: Zinc morphology in zinc-nickel flow assisted batteries and impact on performance, Journal of Power Sources, Vol. 196, pp. 2340-2345, 2011

  However, in the battery described above, there is a concern that the dendrite produced at the negative electrode still grows on the positive electrode side and the negative electrode and the positive electrode are conducted.

  One embodiment of the present invention has been made in view of the above, and an object thereof is to provide a flow battery that can suppress conduction between a negative electrode and a positive electrode.

  The flow battery according to one aspect of the embodiment includes a first electrode and a second electrode, a reaction chamber, an electrolytic solution, and a bubble generator. The reaction chamber is provided with a first restricting portion on the inner wall for accommodating the first electrode and the second electrode and restricting the arrangement of the first electrode. The electrolytic solution is accommodated in the reaction chamber and contacts the first electrode and the second electrode. The bubble generation device generates bubbles by supplying gas into the electrolytic solution.

  According to the flow battery of one aspect of the embodiment, conduction between the negative electrode and the positive electrode can be suppressed.

FIG. 1 is a diagram schematically illustrating the flow battery according to the first embodiment. FIG. 2A is a diagram schematically illustrating a reaction chamber included in the flow battery according to the first embodiment. FIG. 2B is a diagram illustrating an outline of a reaction chamber included in the flow battery according to the first embodiment. FIG. 2C is a diagram illustrating an outline of a reaction chamber provided in the flow battery according to the first embodiment. FIG. 3A is a diagram illustrating an outline of a reaction chamber included in the flow battery according to the first embodiment. FIG. 3B is a diagram illustrating an outline of a reaction chamber included in the flow battery according to the first embodiment. FIG. 4A is a diagram illustrating an outline of a bubble generation unit included in the flow battery according to the first embodiment. FIG. 4B is a diagram illustrating an outline of a bubble generation unit included in the flow battery according to the first embodiment. FIG. 5A is a diagram schematically illustrating a reaction chamber included in the flow battery according to the second embodiment. FIG. 5B is a diagram illustrating an outline of a reaction chamber included in the flow battery according to the second embodiment. FIG. 6 is a diagram illustrating an outline of a reaction chamber provided in a flow battery according to a modification of the first embodiment. FIG. 7 is a diagram illustrating an outline of a reaction chamber provided in a flow battery according to a modification of the first embodiment. FIG. 8 is a diagram showing an outline of a reaction chamber provided in a flow battery according to a modification of the second embodiment.

  Hereinafter, an embodiment of a flow battery disclosed in the present application will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.

  FIG. 1 is a diagram schematically illustrating the flow battery according to the first embodiment. A flow battery 1 shown in FIG. 1 includes a positive electrode 2 as a first electrode, a negative electrode 3 as a second electrode, a diaphragm 4, an electrolytic solution 5, a reaction chamber 10, a pump 11, a supply flow path 12, The bubble generating unit 13, the recovery port 14, and the recovery channel 15 are provided.

  For easy understanding, FIG. 1 shows a three-dimensional orthogonal coordinate system including a Z-axis having a vertically upward direction as a positive direction and a vertically downward direction as a negative direction. Such an orthogonal coordinate system may also be shown in other drawings used in the following description.

  The positive electrode 2 is accommodated in the reaction chamber 10. The positive electrode 2 is a conductive member containing, for example, a nickel compound or a manganese compound as a positive electrode active material. The nickel compound is preferably, for example, nickel oxyhydroxide, nickel hydroxide, cobalt-containing nickel hydroxide, or the like. The manganese compound is preferably, for example, manganese dioxide. The positive electrode 2 may contain a cobalt compound, graphite, carbon black, a conductive resin, and the like. From the viewpoint of the redox potential at which the electrolytic solution 5 is decomposed, the positive electrode 2 preferably contains a nickel compound.

  The negative electrode 3 is accommodated in the reaction chamber 10. The negative electrode 3 contains a negative electrode active material as metallic zinc or a zinc compound. As the negative electrode 3, for example, a metal plate such as stainless steel or copper, or a surface obtained by plating the surface of the stainless steel or copper plate with nickel, tin, or zinc can be used. Moreover, you may use as the negative electrode 3 what the plated surface partially oxidized.

  The diaphragm 4 covers the positive electrode 2. The diaphragm 4 has hydroxide ion conductivity and conducts hydroxide ions involved in the electrode reaction. Moreover, it is preferable that the diaphragm 4 is comprised densely so that metal zinc may not pass. Thereby, the defect which the positive electrode 2 and the negative electrode 3 conduct | electrically_connect because the grown dendrite penetrates the diaphragm 4 can further be suppressed. Here, the term “dense” refers to a relative density of 90% or more calculated by Archimedes method, more preferably 92% or more, and still more preferably 95% or more. Moreover, the thickness of the diaphragm 4 becomes like this. Preferably they are 10 micrometers-1000 micrometers, More preferably, they are 100 micrometers-500 micrometers. However, the relative density and thickness of the diaphragm 4 are not limited to those described above as long as penetration of dendrites can be suppressed.

While the diaphragm 4 selectively transmits hydroxide ions, it is preferable to suppress the transmission of metal ions such as [Zn (OH) ₄ ] ^{2− having} a larger ion radius than the hydroxide ions. Thus, when the diaphragm 4 suppresses the transmission of metal ions such as [Zn (OH) ₄ ] ²⁻ , the formation of dendrite in the diaphragm 4 and in the vicinity of the positive electrode 2 is suppressed. It is possible to further suppress conduction.

  The diaphragm 4 is preferably formed using, for example, a gel-like anion conductive material or a solid polymer type anion conductive material having a three-dimensional structure such as an organic hydrogel. Here, the solid polymer type anion conductive material is, for example, an oxide, a hydroxide, a layered composite containing a polymer and one or more elements selected from Group 1 to Group 17 of the periodic table. And one or more compounds selected from the group consisting of hydroxides, sulfuric acid compounds and phosphoric acid compounds.

The electrolytic solution 5 is accommodated in the reaction chamber 10 so as to contact the positive electrode 2 and the negative electrode 3. The electrolytic solution 5 is, for example, an alkaline aqueous solution containing zinc species. Zinc species in the electrolytic solution 5 are dissolved in the electrolytic solution 5 as [Zn (OH) ₄ ] ²⁻ . As the electrolytic solution 5, for example, an alkaline aqueous solution containing K ⁺ or OH ⁻ and saturated with zinc oxide can be used. Here, as the alkaline aqueous solution, for example, a 6.7 mold ^-3 potassium hydroxide aqueous solution can be used. Moreover, the electrolyte solution 5 can be prepared by adding until the ZnO is saturated with respect to 1 dm- ³ potassium hydroxide aqueous solution.

  The reaction chamber 10 includes a case 8 and an upper plate 9. The case 8 and the upper plate 9 are made of a resin material having alkali resistance and insulation, such as polystyrene, polypropylene, polyethylene terephthalate, and polytetrafluoroethylene. The case 8 and the upper plate 9 are preferably made of the same material as each other, but may be made of different materials.

  The case 8 contains the positive electrode 2, the negative electrode 3, and the electrolytic solution 5. In addition, the case 8 is provided with an opening through which a pipe constituting the supply flow path 12 is inserted or connected. Further, a space is provided between the upper plate 9 and the liquid surface of the electrolytic solution 5, and the gas layer 7 is configured.

  Here, a specific arrangement of the positive electrode 2 and the negative electrode 3 housed in the reaction chamber 10 will be described with reference to FIGS. 2A to 2C. FIG. 2A is a diagram schematically illustrating the reaction chamber 10 provided in the flow battery 1 according to the first embodiment. 2B is a plan view of the reaction chamber 10 shown in FIG. 2A from the positive side of the Z-axis, and FIG. 2C is a cross-sectional view taken along the line II of the reaction chamber 10 shown in FIG. 2B. 2A to 2C, illustration of some members including the diaphragm 4 and the upper plate 9 is omitted. Furthermore, illustration of the electrolyte solution 5 is abbreviate | omitted in FIG. 2A and 2B.

  The case 8 has inner walls 8a and 8b arranged in parallel along the ZX plane so as to face each other across the positive electrode 2 and the negative electrode 3 arranged along the YZ plane, and on both side ends of the inner walls 8a and 8b. Inner walls 8c and 8d arranged along the YZ plane so as to be connected to each other, and a bottom surface 8e arranged at the lower ends of the inner walls 8a, 8b, 8c and 8d along the XY plane.

  On the inner wall 8a, vertical grooves 8a1 and 8a2 extending in the Z-axis direction from the upper end of the case 8 are provided at predetermined intervals, respectively. The inner wall 8b is provided with longitudinal grooves 8b1 and 8b2 extending in the Z-axis direction from the upper end of the case 8 so as to face the longitudinal grooves 8a1 and 8a2.

  The positive electrode 2 is supported by the vertical groove 8a1 and the vertical groove 8b1, and movement of the positive electrode 2 in the reaction chamber 10 is restricted. The negative electrode 3 is supported by the vertical groove 8a2 and the vertical groove 8b2, and the movement of the negative electrode 3 in the reaction chamber 10 is restricted.

  First, the vertical groove 8a1 and the vertical groove 8b1 will be described. The vertical groove 8a1 and the vertical groove 8b1 have a width corresponding to the width of the side surfaces 2a and 2b of the positive electrode 2 in the X-axis direction, that is, the thickness of the positive electrode 2, respectively. For this reason, the positive electrode 2 is restricted from moving in the X-axis direction. Here, the “width corresponding to the thickness” of the positive electrode 2 is a width in consideration of a safety margin based on molding accuracy. That is, the widths of the vertical grooves 8a1 and the vertical grooves 8b1 preferably match the thickness of the positive electrode 2. However, the width is not limited to this, and is not necessarily the same as the thickness of the positive electrode 2 as long as the positive electrode 2 can be accommodated. May be.

  The vertical groove 8a1 and the vertical groove 8b1 have a distance corresponding to the length of the positive electrode 2 in the Y-axis direction, that is, the horizontal width of the positive electrode 2. For this reason, the positive electrode 2 is restricted from moving in the Y-axis direction. Here, the “interval corresponding to the lateral width” of the positive electrode 2 is a width in consideration of a safety margin based on molding accuracy. That is, the interval between the vertical groove 8a1 and the vertical groove 8b1 is preferably equal to the horizontal width of the positive electrode 2, but is not limited thereto, and is not necessarily equal to the horizontal width of the positive electrode 2 as long as the positive electrode 2 can be accommodated. May be.

  As shown in FIG. 2C, the vertical groove 8 a 1 has a lower end 21, and the vertical groove 8 b 1 has a lower end 31 at a position corresponding to the lower end 21. The lower ends 21 and 31 are provided above the bottom surface 8e of the case 8, and a space 17 through which the electrolytic solution 5 can flow is formed between the positive electrode 2 and the bottom surface 8e. By disposing the lower surface 2e of the positive electrode 2 in contact with the lower ends 21 and 31, the positive electrode 2 is restricted from moving in the negative Z-axis direction, that is, downward.

  Next, the vertical groove 8a2 and the vertical groove 8b2 will be described. The vertical groove 8 a 2 and the vertical groove 8 b 2 have a width corresponding to the width of the side surfaces 3 a and 3 b of the negative electrode 3 in the X-axis direction, that is, the thickness of the negative electrode 3. For this reason, the negative electrode 3 is restricted from moving in the X-axis direction.

  Further, the vertical groove 8 a 2 and the vertical groove 8 b 2 have a distance corresponding to the length of the negative electrode 3 in the Y-axis direction, that is, the horizontal width of the negative electrode 3. For this reason, the negative electrode 3 is restricted from moving in the Y-axis direction. Further, the vertical groove 8a2 and the vertical groove 8b2 have a lower end (not shown). The lower end is provided above the bottom surface 8e of the case 8 similarly to the lower ends 21 and 31, and a space in which the electrolyte solution 5 can flow is formed between the negative electrode 3 and the bottom surface 8e. By disposing the lower end surface (not shown) of the negative electrode 3 in contact with the lower ends of the vertical groove 8a2 and the vertical groove 8b2, the negative electrode 3 is restricted from moving in the negative Z-axis direction, that is, downward.

  That is, the vertical groove 8 a 1 and the vertical groove 8 b 1 constitute a first restriction part that restricts the arrangement of the positive electrode 2 in the reaction chamber 10. Similarly, the vertical groove 8a2 and the vertical groove 8b2 constitute a second restricting portion that restricts the arrangement of the negative electrode 3 in the reaction chamber 10. As described above, by directly providing the restriction portion for restricting the movement of the positive electrode 2 and the negative electrode 3 in the case 8 of the reaction chamber 10, for example, a rack in which the positive electrode 2 and the negative electrode 3 are previously arranged at a predetermined interval is accommodated in the case 8. The case 8 can be downsized as compared with the configuration. Moreover, since the positive electrode 2 and the negative electrode 3 can be directly arranged in the restriction part provided in the reaction chamber 10, the number of parts can be reduced.

  Returning to FIG. 1, the flow battery 1 according to the first embodiment will be further described. The pump 11 is, for example, a gas pump, and sends the gas recovered from the reaction chamber 10 via the recovery port 14 and the recovery flow path 15 to the bubble generation unit 13 via the supply flow path 12. The pump 11 preferably has high airtightness so as not to reduce the power generation performance of the flow battery 1 by leaking the gas that is the generation source of the bubbles 6 or the water vapor derived from the electrolyte 5 to the outside.

  The bubble generating unit 13 is disposed in the lower part of the reaction chamber 10. The bubble generating unit 13 is connected to the pump 11 via a supply channel 12 that communicates the inside and outside of the case 8 of the reaction chamber 10. The bubble generating unit 13 supplies the gas sent from the pump 11 into the electrolytic solution 5 and generates bubbles 6. That is, the flow battery 1 according to the embodiment includes a bubble generation device including a pump 11 and a bubble generation unit 13. A specific configuration example of the bubble generating unit 13 will be described later.

  The bubble 6 is comprised with the gas inert with respect to the electrolyte solution 5, for example. Examples of such a gas include air, nitrogen gas, helium gas, neon gas, and argon gas. By generating inert gas bubbles 6 in the electrolytic solution 5, denaturation of the electrolytic solution 5 can be suppressed. The bubbles 6 generated by the gas supplied from the bubble generation unit 13 flow upward in the electrolytic solution 5 between the positive electrode 2 and the negative electrode 3. The gas that has flowed as bubbles 6 in the electrolytic solution 5 disappears at the liquid surface of the electrolytic solution 5, and constitutes a gas layer 7 above the electrolytic solution 5 in the reaction chamber 10.

  The recovery port 14 is provided in the upper part of the reaction chamber 10. One of the recovery ports 14 is connected to the pump 11 via a recovery flow path 15, and the other opens to the gas layer 7 formed in the reaction chamber 10. The recovery port 14 discharges the gas recovered from the reaction chamber 10 to the outside of the reaction chamber 10 and sends it to the pump 11. In the example shown in FIG. 1, the recovery port 14 is arranged at a position overlapping the bubble generating unit 13 when viewed from the Z-axis direction. However, the present invention is not limited to this, and any type can be used as long as it opens to face the gas layer 7. It may be arranged at a position. In the example shown in FIG. 1, the collection port 14 is arranged at one place, but the present invention is not limited to this, and a plurality of collection ports 14 may be arranged.

  Here, the electrode reaction in the reaction chamber 10 will be described by taking a nickel zinc flow battery to which nickel hydroxide is applied as a positive electrode active material as an example. The reaction formulas at the positive electrode 2 and the negative electrode 3 during charging are as follows.

Positive electrode: Ni (OH) ₂ + OH ⁻ → NiOOH + H ₂ O + e ⁻
Negative electrode: [Zn (OH) ₄ ] ² + 2e ⁻ → Zn + 4OH ⁻

As apparent from the reaction formula, in the negative electrode 3, the concentration of [Zn (OH) ₄ ] ²⁻ in the electrolytic solution 5 in the vicinity of the negative electrode 3 decreases as zinc is deposited by charging. Then, when the electrolytic solution 5 in which the concentration of [Zn (OH) ₄ ] ²⁻ is reduced stays in the vicinity of the negative electrode 3, the zinc deposited on the negative electrode 3 becomes a cause of growing as dendrites. That is, when the electrolytic solution 5 in which the concentration of [Zn (OH) ₄ ] ²⁻ is locally decreased by the charging reaction is caused to flow quickly without staying in the vicinity of the negative electrode 3, dendrite growth is suppressed.

  Therefore, in the flow battery 1 according to the first embodiment, gas 6 is generated by supplying gas into the electrolytic solution 5 from the bubble generating unit 13 of the bubble generating device provided in the lower part of the reaction chamber 10. . The bubbles 6 flow between the positive electrode 2 and the negative electrode 3 so as to rise in the electrolytic solution 5 from the lower side to the upper side of the reaction chamber 10. Further, as the bubbles 6 flow, the electrolytic solution 5 flows so as to circulate inside the reaction chamber 10. This point will be described with reference to FIGS. 3A and 3B.

  3A and 3B are diagrams schematically illustrating the reaction chamber 10 provided in the flow battery 1 according to the first embodiment. 3A and 3B correspond to II-II sectional views of the reaction chamber 10 shown in FIG. 2B. FIG. 3A is an example in which the bubble generating part 13 is arranged in the middle part of the inner walls 8a and 8b, and FIG. 3B is an example in which the bubble generating part 13 is arranged in a place close to the inner wall 8a.

  First, a configuration example of the bubble generating unit 13 will be described with reference to FIGS. 4A and 4B. The bubble generating unit 13 shown in FIG. 4A has a plurality of openings 13a arranged in a row. The bubble generating unit 13 is disposed in the lower part of the reaction chamber 10, more specifically, on the bottom surface 8 e of the case 8 containing the electrolytic solution 5. The bubble generating unit 13 generates bubbles 6 in the electrolytic solution 5 from the opening 13 a by the gas supplied from the pump 11.

  The arrangement of the openings 13a shown in FIG. 4A is not limited to that shown in the figure, and the openings 13a may be arranged in a plurality of rows, and the number of the openings 13a may be one. Moreover, as long as the electrolyte 5 flows appropriately, the size of the bubble generating part 13 is not limited, but it is preferably arranged so as not to contact the positive electrode 2 and the negative electrode 3 in order to continuously perform an appropriate battery reaction. . Further, as shown in FIG. 4B, a porous body made of, for example, ceramics may be used as the bubble generating unit 13. In such a case, a configuration corresponding to the opening 13a is not necessary.

  Returning to FIGS. 3A and 3B, the circulation of the electrolytic solution 5 accompanying the flow of the bubbles 6 will be further described. As described above, as the bubbles 6 flow between the positive electrode 2 and the negative electrode 3, a rising liquid flow is generated in the electrolytic solution 5. That is, between the positive electrode 2 and the negative electrode 3, the electrolyte solution 5 flows from the lower side to the upper side of the case 8 at a location close to the bubbles 6. In the example shown in FIG. 3A, a descending liquid flow of the electrolytic solution 5 is generated in the vicinity of both the inner wall 8 a and the inner wall 8 b along with the rising liquid flow of the electrolytic solution 5 generated in the central portion of the inner walls 8 a and 8 b. The electrolytic solution 5 flows from the upper side to the lower side of the case 8 along the inner wall 8a and the inner wall 8b.

  On the other hand, in the example shown in FIG. 3B, with the rising liquid flow of the electrolytic solution 5 flowing along the inner wall 8a, a falling liquid flow is generated in the vicinity of the inner wall 8b, so that the electrolytic solution 5 runs along the inner wall 8b. The fluid flows from the upper side of the case 8 to the lower side. That is, in both the examples shown in FIG. 3A and FIG. 3B, the electrolyte solution 5 between the positive electrode 2 and the negative electrode 3 is obtained by disposing the bubble generating part 13 in a part between the positive electrode 2 and the negative electrode 3. The inside of the reaction chamber 10 can be circulated along the YZ plane.

As described above, in the flow battery 1 according to the first embodiment, the [Zn (OH) ₄ ] ²⁻ concentration of the [Zn (OH) ₄ ] ²⁻ is rapidly circulated to rapidly circulate [Zn ( OH) ₄ ] ^2- concentration can be kept uniform, and conduction between the negative electrode 3 and the positive electrode 2 accompanying dendrite growth can be suppressed.

Here, the distance between the vertical groove 8a1 and the vertical groove 8a2 is preferably set so that the distance between the negative electrode 3 and the diaphragm 4 (see FIG. 1) is 1 cm or less. By setting the distance between the negative electrode 3 and the diaphragm 4 to 1 cm or less, it is possible to suppress a voltage drop due to ion conduction between the electrodes. Further, since the bubbles 6 can be reliably flowed in the vicinity of the negative electrode 3, the concentration of [Zn (OH) ₄ ] ^{2− in} the electrolytic solution 5 can be quickly made uniform, which accompanies the growth of dendrites. The conduction between the negative electrode 3 and the positive electrode 2 can be suppressed.

  In the above-described embodiment, the arrangement of the electrodes is regulated by the vertical grooves provided in the inner walls 8a and 8b, but the present invention is not limited to this. This point will be described below with reference to FIGS. 5A and 5B.

  FIG. 5A is a diagram schematically showing the reaction chamber 10 provided in the flow battery 1 according to the second embodiment, and FIG. 5B is a cross-sectional view taken along the line III-III in FIG. 5A.

  The inner wall 8a is provided with guide portions 18a1 and 18a2 configured to protrude from the inner wall 8a, instead of the longitudinal grooves 8a1 and 8a2 shown in FIGS. 2A to 2C. In addition, instead of the vertical grooves 8b1 and 8b2, guide portions 18b1 and 18b2 configured to protrude from the inner wall 8b are provided on the inner wall 8b so as to face the guide portions 18a1 and 18a2, respectively.

  The positive electrode 2 is supported by a guide portion 18a1 and a guide portion 18b1 as first convex portions. The guide portion 18a1 includes convex portions 22 and 23 arranged at intervals corresponding to the thickness of the side surface 2a of the positive electrode 2. The guide portion 18b1 includes convex portions 32 and 33 arranged at intervals corresponding to the thickness of the side surface 2b of the positive electrode 2. For this reason, the movement of the positive electrode 2 in the X-axis direction is restricted by the guide portion 18a1 and the guide portion 18b1.

  Further, the lateral width of the positive electrode 2 corresponds to the distance between the inner wall 8a and the inner wall 8b, and movement of the positive electrode 2 in the reaction chamber 10 in the Y-axis direction is restricted.

  Further, as shown in FIG. 5B, the inner wall 8a is provided with an abutting portion 24 configured to protrude from the inner wall 8a instead of the lower end 21, and the inner wall 8b is abutted instead of the lower end 31. A contact portion 34 configured to protrude from the inner wall 8 b is provided at a position corresponding to the contact portion 24. The lower surface 2e of the positive electrode 2 is disposed so as to come into contact with the contact portions 24 and 34 as the second convex portions, whereby the positive electrode 2 is restricted from moving in the negative Z-axis direction, that is, downward.

  Next, a configuration for restricting the arrangement of the negative electrode 3 will be described. The negative electrode 3 is supported by the guide part 18a2 and the guide part 18b2. The guide portion 18a2 includes convex portions 25 and 26 arranged at intervals corresponding to the thickness of the side surface 3a of the negative electrode 3. Further, the guide portion 18b2 includes convex portions 35 and 36 arranged at intervals corresponding to the thickness of the side surface 3b of the negative electrode 3. Therefore, the movement of the negative electrode 3 in the X-axis direction is restricted by the guide portion 18a2 and the guide portion 18b2.

  The lateral width of the negative electrode 3 corresponds to the distance between the inner wall 8a and the inner wall 8b, and movement of the negative electrode 3 in the reaction chamber 10 in the Y-axis direction is restricted. The inner wall 8b is provided with a contact portion (not shown) configured to protrude from the inner wall 8b. By disposing the lower surface of the negative electrode 3 so as to come into contact with a contact portion (not shown), the negative electrode 3 is restricted from moving in the negative Z-axis direction, that is, downward.

  That is, the guide part 18 a 1, the contact part 24, the guide part 18 b 1, and the contact part 34 constitute a first restriction part that restricts the arrangement of the positive electrode 2 in the reaction chamber 10. Similarly, the guide portion 18 a 2, the guide portion 18 b 2, and the contact portion (not shown) constitute a second restriction portion that restricts the arrangement of the negative electrode 3 in the reaction chamber 10. Thus, instead of the groove-shaped restriction portions provided on the inner wall 8a and the inner wall 8b, the restriction portions protruding from the inner wall 8a and the inner wall 8b are provided, thereby reducing the size of the positive electrode 2 and the negative electrode 3 in the Y-axis direction. For example, the manufacturing cost can be reduced.

  In the above-described embodiment, it has been described that there is a space in which the electrolytic solution 5 can flow between the positive electrode 2 and the negative electrode 3 and the bottom surface 8e of the case 8, but the present invention is not limited thereto. This point will be described with reference to FIG.

  FIG. 6 is a diagram showing an outline of the reaction chamber 10 provided in the flow battery 1 according to the modification of the first embodiment. The reaction chamber 10 shown in FIG. 6 is shown in FIGS. 2A to 2C except that the vertical groove 8a1 and the vertical groove 8b1 and the vertical groove 8a2 and the vertical groove 8b2 (not shown here) are provided in contact with the bottom surface 8e. It has the same configuration as the reaction chamber 10 according to the first embodiment shown. According to the reaction chamber 10 configured as described above, for example, the reaction chamber 10 can be downsized in the Z-axis direction as compared with the reaction chamber 10 having a space between the positive electrode 2 and the negative electrode 3 and the bottom surface 8 e of the case 8. it can.

  In the above-described embodiment, the first restricting portion and the second restricting portion are described as being provided on the inner walls 8a and 8b. However, the present invention is not limited to this, and it is only necessary to provide the inner surface of the reaction chamber 10 including the bottom surface 8e. . This point will be described with reference to FIGS.

  First, FIG. 7 will be described. FIG. 7 is a diagram illustrating an outline of the reaction chamber 10 provided in the flow battery 1 according to the modification of the first embodiment. The reaction chamber 10 shown in FIG. 7 has a lateral groove 8e1 having a width corresponding to the thickness of the lower surface 2e of the positive electrode 2 and a lateral groove (not shown) having a width corresponding to the thickness of the lower surface of the negative electrode 3 on the bottom surface 8e of the case 8. Except for being provided, it has the same configuration as the reaction chamber 10 shown in FIG.

  According to the reaction chamber 10 configured as described above, the movement of the positive electrode 2 and the negative electrode 3 can be regulated in the three directions of the inner walls 8a and 8b and the bottom surface 8e. For example, the lifetimes of the positive electrode 2 and the negative electrode 3 are increased. .

  Next, FIG. 8 will be described. FIG. 8 is a diagram showing an outline of the reaction chamber 10 provided in the flow battery 1 according to the modification of the second embodiment. The reaction chamber 10 shown in FIG. 8 is provided with contact portions 44 and 54 configured to protrude from the bottom surface 8e instead of the contact portions 24 and 34 protruding from the inner walls 8a and 8b. It has the same configuration as the reaction chamber 10 shown in FIG. 5B.

  According to the reaction chamber 10 configured as described above, the contact portions 44 and 54 are not dropped due to the load received from the positive electrode 2 and the negative electrode 3. For example, the strength of the contact portions 44 and 54 can be reduced. And the degree of design freedom is improved.

  As mentioned above, although each embodiment of this invention was described, this invention is not limited to each said embodiment, A various change is possible unless it deviates from the meaning. For example, you may use combining suitably the combination of the 1st control part and 2nd control part which concern on each embodiment and a modification. Further, the restricting portion may be applied to only one of the positive electrode 2 and the negative electrode 3. In such a case, the arrangement of the other electrode may be regulated by fixing a current collector plate, for example.

  In the above-described embodiment, the bubble generation unit 13 has been described as being disposed on the bottom surface 8e of the case 8. However, the present invention is not limited thereto, and the bubble generation unit 13 may be disposed so as to be embedded inside the bottom surface 8e.

  In the above-described embodiment, the example in which the bubble generation unit 13 is unevenly distributed in the middle portion of the inner walls 8a and 8b or a location close to the inner wall 8a has been described. You may arrange | position so that it may extend. Above and below the positive electrode 2 and the negative electrode 3, there is an electrolyte 5 that can flow along the XY plane. For this reason, the electrolytic solution 5 flows over the positive electrode 2 and the negative electrode 3 so as to move parallel to both the inner wall 8c and the inner wall 8d, and further above the case 8 so as to follow the inner wall 8c and the inner wall 8d. It flows downward from. That is, according to the flow battery 1 including the bubble generating unit 13 having such a configuration, the electrolyte solution 5 circulates not only between the electrodes but also throughout the reaction chamber 10.

  In the above-described embodiment, it has been described that the positive electrode 2 and the negative electrode 3 are housed one by one in the reaction chamber 10, but the present invention is not limited thereto, and a plurality of positive electrodes 2 and negative electrodes 3 may be arranged. At this time, in the flow battery 1 in which the positive electrode 2 and the negative electrode 3 are alternately arranged so that the two negative electrodes 3 correspond to one positive electrode 2, the flow in which the positive electrode 2 and the negative electrode 3 correspond 1: 1. Compared with the battery 1, the current density per negative electrode is lowered. For this reason, according to the flow battery 1 which has this structure, since the production | generation of the dendrite in the negative electrode 3 is further suppressed, conduction | electrical_connection with the negative electrode 3 and the positive electrode 2 can further be suppressed.

  In the above-described embodiment, the diaphragm 4 has been described as covering the positive electrode 2. However, the present invention is not limited to this, and it may be disposed between the positive electrode 2 and the negative electrode 3.

The pump 11 may be operated at all times. However, from the viewpoint of suppressing power consumption, it is preferable to operate the pump 11 only at the time of charging / discharging in which the concentration of the electrolyte in the electrolytic solution 5 is likely to be biased. It is more preferable to operate only occasionally. Moreover, you may comprise so that the supply speed | rate of the gas supplied from the bubble generation part 13 may be changed according to the consumption rate of [Zn (OH) ₄ ] ^{2- in} the electrolyte solution 5. FIG.

  Further effects and modifications can be easily derived by those skilled in the art. Thus, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications can be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

DESCRIPTION OF SYMBOLS 1 Flow battery 2 Positive electrode 3 Negative electrode 4 Diaphragm 5 Electrolyte 6 Bubble 7 Gas layer 8 Case 9 Upper board 10 Reaction chamber 11 Pump 12 Supply flow path 13 Bubble generation part 14 Recovery port 15 Recovery flow path

Claims (7)

A first electrode and a second electrode;
A reaction chamber for accommodating the first electrode and the second electrode, comprising a first regulating portion on the inner surface for regulating the arrangement of the first electrode;
An electrolyte contained in the reaction chamber and in contact with the first electrode and the second electrode;
A flow battery comprising: a bubble generating device that supplies gas into the electrolyte solution to generate bubbles.   The flow battery according to claim 1, wherein the first restricting portion includes a groove having a width corresponding to a thickness of the first electrode.   3. The flow battery according to claim 1, wherein the first restriction portion includes a plurality of first protrusions arranged at intervals corresponding to the thickness of the first electrode.   The flow battery according to claim 1, wherein the first restricting portion includes a second convex portion that restricts a height of a bottom surface of the first electrode. The flow battery according to any one of claims 1 to 4, wherein the inner surface further includes a second restriction portion that restricts the arrangement of the second electrode. The flow battery according to any one of claims 1 to 5, wherein the first electrode is a positive electrode and the second electrode is a negative electrode. Further comprising a diaphragm disposed between the first electrode and the second electrode;
The flow cell according to any one of claims 1 to 6, wherein the bubbles flow in the electrolyte solution between the second electrode and the diaphragm.

Images