JP2019079750A - Flow battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow battery capable of suppressing collision of bubbles discharged from a flow device with an active material. A flow battery includes a positive electrode and a negative electrode, an electrolytic solution, a flow device, and a collision suppressing member. The electrolytic solution contacts the positive electrode and the negative electrode. The flow device includes a generating unit that generates bubbles in the electrolytic solution and causes the electrolytic solution to flow. The collision suppressing member is provided below at least one of the positive electrode and the negative electrode so as to protrude from the main surface of the positive electrode or the negative electrode. [Selection diagram] Figure 1

Description

  Embodiments of the disclosure relate to flow batteries.

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

  There is also proposed a technology for suppressing the growth of dendrite by covering a negative electrode containing an active material such as a zinc species with an ion conductive layer having selective ion conductivity (see, for example, Patent Document 1).

JP, 2015-185259, A

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, when the bubbles released from the flow device for circulating the electrolyte collide with the active material generated on the electrode surface, the active material falls off from the electrode surface and does not contribute to charge and discharge. There is a concern that the battery performance may be degraded by staying in the state.

  One aspect of an embodiment is made in view of the above, and it aims at providing a flow battery which can control that a bubble emitted from a flow device collides with an active material.

  The flow battery according to one aspect of the embodiment includes a positive electrode and a negative electrode, an electrolytic solution, a flow device, and a collision suppression member. An electrolytic solution contacts the positive electrode and the negative electrode. The flow device includes a generator for generating bubbles in the electrolyte, and causes the electrolyte to flow. The collision suppressing member is provided below the positive electrode and at least one of the negative electrode so as to protrude with respect to the main surface of the positive electrode or the negative electrode.

  According to one aspect of the embodiment, it is possible to suppress that the air bubbles emitted from the flow device collide with the active material.

FIG. 1 is a schematic view of a flow battery according to an embodiment. FIG. 2 is a view for explaining an example of connection between electrodes of the flow battery according to the embodiment. FIG. 3 is a schematic view of a flow battery according to a modification of the embodiment.

  Hereinafter, embodiments of the disclosed flow battery will be described in detail with reference to the attached drawings. Note that the present invention is not limited by the embodiments described below.

Embodiment
FIG. 1 is a schematic view of a flow battery 1 according to an embodiment. The flow battery 1 shown in FIG. 1 includes the positive electrode 2, the negative electrode 3, the diaphragms 4 and 5, the electrolytic solution 6, the powder 7, the generating unit 9, the supply unit 14, the housing 17, and the upper plate 18. And The flow battery 1 is a device that causes the electrolytic solution 6 to flow by causing the bubbles 8 generated in the generation unit 9 to float. The generation unit 9 is an example of a flow device.

  In order to make the description easy to understand, FIG. 1 illustrates a three-dimensional orthogonal coordinate system including a Z axis in which the vertically upward direction is a positive direction and the vertically downward direction is 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 a conductive member containing, for example, a nickel compound, a manganese compound or a cobalt compound as a positive electrode active material. As the nickel compound, for example, nickel oxyhydroxide, nickel hydroxide, nickel compound-containing nickel hydroxide and the like can be used. As the manganese compound, for example, manganese dioxide can be used. As the cobalt compound, for example, cobalt hydroxide, cobalt oxyhydroxide and the like can be used. In addition, the positive electrode 2 may contain graphite, carbon black, a conductive resin, and the like. From the viewpoint of the redox potential at which the electrolytic solution 6 is decomposed, the positive electrode 2 may contain a nickel compound.

  The negative electrode 3 contains a negative electrode active material as a metal. The negative electrode 3 may be, for example, a metal plate of stainless steel, copper or the like, or a stainless steel plate or copper plate whose surface is plated with nickel, tin or zinc. In addition, the negative electrode 3 may be used in which the plated surface is partially oxidized.

  Positive electrode 2 includes a positive electrode 2A and a positive electrode 2B. Negative electrode 3 includes negative electrode 3A, negative electrode 3B and negative electrode 3C. The positive electrode 2 and the negative electrode 3 are arranged such that the negative electrode 3A, the positive electrode 2A, the negative electrode 3B, the positive electrode 2B, and the negative electrode 3C are arranged in order along the Y-axis direction at predetermined intervals. Thus, by providing the space | interval of the positive electrode 2 and the negative electrode 3 which adjoin each other, the flow path of the electrolyte solution 6 and the bubble 8 between the positive electrode 2 and the negative electrode 3 is ensured.

  The diaphragms 4 and 5 are disposed so as to sandwich both sides in the thickness direction of the positive electrode 2, that is, the Y-axis direction. The diaphragms 4 and 5 are made of a material that allows the movement of ions contained in the electrolytic solution 6. Examples of the material of the membranes 4 and 5 include anion conductive materials having hydroxide ion conductivity. Examples of the anion-conductive material include gel-like anion-conductive materials having a three-dimensional structure such as organic hydrogels, solid polymer-type anion-conductive materials, and the like. The solid polymer type anion conductive material is, for example, an oxide, hydroxide, layered double hydroxide, containing a polymer and at least one element selected from Groups 1 to 17 of the periodic table. And at least one compound selected from the group consisting of sulfuric acid compounds and phosphoric acid compounds.

The diaphragms 4 and 5 are preferably made of a compact material so as to suppress the permeation of metal ion complexes such as [Zn (OH) ₄ ] ^2- or the like having a larger ion radius than hydroxide ions. It has a predetermined thickness. Examples of the dense material include materials having a relative density of 90% or more, more preferably 92% or more, and even more preferably 95% or more, as calculated by the Archimedes method. The predetermined thickness is, for example, 10 μm to 1000 μm, more preferably 50 μm to 500 μm.

  In this case, zinc deposited in the negative electrodes 3A to 3C grows as dendrites (needle-like crystals) during charging, and penetration of the diaphragms 4 and 5 can be reduced. As a result, the conduction between the negative electrode 3 and the positive electrode 2 facing each other can be reduced.

The electrolytic solution 6 is an alkaline aqueous solution containing a zinc species. Zinc species in the electrolyte 6 are dissolved in the electrolyte 6 as [Zn (OH) ₄ ] ²⁻ . As the electrolytic solution 6, for example, one in which an alkaline aqueous solution containing K ⁺ or OH ⁻ is saturated with zinc species can be used. In addition, if the electrolyte solution 6 is prepared with the powder 7 mentioned later, charge capacity can be enlarged. Here, as an aqueous alkali solution, for example, an aqueous solution of 6.7 moldm ⁻³ potassium hydroxide can be used. Moreover, the electrolyte solution 6 can be prepared by adding ZnO in the ratio of 0.5 mol with respect to the potassium hydroxide aqueous solution of 1 dm < ^-3 >, and adding the powder 7 mentioned later as needed. Further, hydroxides of alkali metals such as lithium hydroxide and sodium hydroxide may be added for the purpose of suppressing the generation of oxygen.

Powder 7 contains zinc. Specifically, the powder 7 is, for example, zinc oxide, zinc hydroxide or the like processed or produced into powder. The powder 7 is easily dissolved in the alkaline aqueous solution, but dispersed or suspended in the electrolytic solution 6 saturated with zinc species without being dissolved or suspended, and mixed in the electrolytic solution 6 in a partially precipitated state. When the electrolyte solution 6 is left standing for a long time, most of the powder 7 may be in a state of settling in the electrolyte solution 6, but if convection is caused in the electrolyte solution 6, sedimentation occurs. A portion of the powder 7 is dispersed or suspended in the electrolyte solution 6. That is, the powder 7 is movably present in the electrolytic solution 6. Here, movable means that the powder 7 can move only in the local space formed between other surrounding powders 7 but the powder 7 can be moved to another position in the electrolytic solution 6 The movement indicates that the powder 7 is exposed to the electrolyte solution 6 other than the initial position. Furthermore, in the movable category, the powder 7 can be moved to the vicinity of both of the positive electrode 2 and the negative electrode 3, or the powder 7 can be almost anywhere in the electrolytic solution 6 present in the housing 17. Includes being able to move. When the zinc species [Zn (OH) ₄ ] ^2- dissolved in the electrolyte solution 6 is consumed, the powder 7 mixed with the electrolyte solution 6 maintains the powder 7 and the electrolyte solution 6 in equilibrium with each other. Thus, the zinc species dissolved in the electrolyte solution 6 are dissolved until saturation.

  The bubble 8 is made of, for example, a gas inert to the positive electrodes 2A, 2B, the negative electrodes 3A, 3B, 3C and the electrolytic solution 6. Examples of such a gas include nitrogen gas, helium gas, neon gas, or argon gas. Degeneration of the electrolyte solution 6 can be reduced by generating an inert gas bubble 8 in the electrolyte solution 6. In addition, for example, deterioration of the electrolytic solution 6 which is an alkaline aqueous solution containing a zinc species can be reduced, and the ion conductivity of the electrolytic solution 6 can be maintained high. The gas may be air.

  The bubbles 8 generated by the gas supplied from the generating portion 9 into the electrolytic solution 6 are between the electrodes arranged at predetermined intervals, that is, between the negative electrode 3A and the positive electrode 2A, between the positive electrode 2A and the negative electrode 3B, The electrolytic solution 6 floats up between the negative electrode 3B and the positive electrode 2B and between the positive electrode 2B and the negative electrode 3C. The gas that floats up as bubbles 8 in the electrolyte solution 6 disappears at the liquid surface of the electrolyte solution 6, and forms a gas layer 13 between the upper plate 18 and the liquid surface of the electrolyte solution 6.

  Here, the electrode reaction in the flow battery 1 will be described by taking a nickel zinc 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 at the time of charge are as follows.

Positive electrode: Ni (OH) ₂ + OH ⁻ → NiOOH + H ₂ O + e ⁻
The negative ^{_{electrode: [Zn (OH) 4]}} 2- + 2e - → Zn + 4OH -

In general, there is a concern that the dendrite generated at the negative electrode 3 grows toward the positive electrode 2 along with this reaction, and the positive electrode 2 and the negative electrode 3 become conductive. As apparent from the reaction formula, in the negative electrode 3, the concentration of [Zn (OH) ₄ ] ²⁻ in the vicinity of the negative electrode 3 decreases as zinc is deposited by charging. And the phenomenon in which the concentration of [Zn (OH) ₄ ] ^2- is lowered in the vicinity of the deposited zinc is one of the causes for the growth as dendrite. That is, by replenishing [Zn (OH) ₄ ] ^2- in the electrolyte solution 6 consumed at the time of charge, the concentration of the zinc species [Zn (OH) ₄ ] ^2-in the electrolyte solution 6 is saturated. Will be held by Thereby, the growth of dendrite is reduced and the conduction between the positive electrode 2 and the negative electrode 3 is reduced.

  In the flow battery 1 according to the embodiment, the powder 7 containing zinc is mixed in the electrolytic solution 6, and a gas is supplied from the discharge port 9 a of the generation unit 9 into the electrolytic solution 6 to generate the bubbles 8. The bubbles 8 are from the lower side to the upper side of the housing 17 in between the negative electrode 3A and the positive electrode 2A, between the positive electrode 2A and the negative electrode 3B, between the negative electrode 3B and the positive electrode 2B, and between the positive electrode 2B and the negative electrode 3C. The surface of the electrolytic solution 6 is floated upward.

  Further, with the floating of the air bubbles 8 between the electrodes, a rising liquid flow is generated in the electrolytic solution 6, and the negative electrode 3B and the positive electrode 2B are generated between the negative electrode 3A and the positive electrode 2A, between the positive electrode 2A and the negative electrode 3B. During the period, the electrolytic solution 6 flows upward from the inner bottom side of the housing 17 between the positive electrode 2B and the negative electrode 3C. Then, with the rising liquid flow of the electrolyte 6, a descending liquid flow is mainly generated between the inner wall 17a of the housing 17 and the negative electrode 3A and between the inner wall 17b and the negative electrode 3C, and the electrolyte 6 is It flows from the top of 17 to the bottom.

Thereby, when [Zn (OH) ₄ ] ^2- in the electrolytic solution 6 is consumed by charging, zinc in the powder 7 is dissolved to follow this [Zn (OH) ₄ ] ^2-2 Is replenished into the electrolyte solution 6. Therefore, the concentration of [Zn (OH) ₄ ] ^2-in the electrolytic solution 6 can be maintained in a saturated state, and the conduction between the positive electrode 2 and the negative electrode 3 can be reduced along with the growth of dendrite.

  In addition to zinc oxide and zinc hydroxide, examples of the powder 7 include metal zinc, calcium zincate, zinc carbonate, zinc sulfate, zinc chloride and the like, with zinc oxide and zinc hydroxide being preferable.

In addition, in the negative electrode 3, Zn is consumed by discharge to generate [Zn (OH) ₄ ] ²⁻ , but since the electrolytic solution 6 is already in a saturated state, it becomes excessive in the electrolytic solution 6 [Zn ZnO is precipitated from (OH) ₄ ] ²⁻ . The zinc consumed by the negative electrode 3 at this time is zinc deposited on the surface of the negative electrode 3 at the time of charge. Therefore, unlike the case where charge and discharge are repeated using the negative electrode originally containing zinc species, so-called shape change in which the surface shape of the negative electrode 3 changes is not generated. Thereby, according to the flow battery 1 which concerns on embodiment, the time-dependent deterioration of the negative electrode 3 can be reduced. In addition, depending on the state of the electrolyte solution 6, what precipitates out from [Zn (OH) ₄ ] ^{2 −} which is excessive is a mixture of Zn (OH) ₂ or ZnO and Zn (OH) ₂ .

  The flow battery 1 according to the embodiment will be further described. The generating unit 9 is disposed below the housing 17, more specifically below the positive electrode 2 and the negative electrode 3. The generation unit 9 has a plurality of discharge ports 9 a aligned along the X-axis direction and the Y-axis direction. The discharge port 9 a generates bubbles 8 in the electrolytic solution 6 by discharging a gas supplied from a supply unit 14 described later. The discharge port 9a has a diameter of, for example, 0.05 mm or more and 0.1 mm or less. By defining the diameter of the discharge port 9 a in this manner, it is possible to reduce the problem that the electrolytic solution 6 and the powder 7 enter from the discharge port 9 a into the inside of the generating portion 9. Further, a pressure loss suitable for generating the bubbles 8 can be given to the gas discharged from the discharge port 9a.

  Moreover, the space | interval (pitch) along the X-axis direction of the discharge port 9a is 2.5 mm or more and 10 mm or less, for example. However, the size and the interval of the discharge ports 9a are not limited as long as the generated bubbles 8 can be appropriately flowed between the positive electrode 2 and the negative electrode 3 facing each other.

  As described above, zinc deposited by charging adheres to the surface of the negative electrode 3, in particular, to the main surface 3 a of the negative electrode 3 facing the positive electrode 2. When the bubbles 8 flowing in the vicinity of the negative electrode 3 collide with the zinc attached to the main surface 3a, the zinc is dropped from the main surface 3a and stays in the housing 17 without contributing to charge and discharge. It can not be used as a substance, and there is a concern that the coulomb efficiency may decrease and the cycle life may decrease. In addition, if zinc adhering to the main surface 3a of the negative electrode 3 falls off on the generation portion 9 and stays there, there is a possibility that short circuit may occur due to clogging of the discharge port 9a or conduction with the negative electrode 3 or the positive electrode 2.

  Therefore, in the flow battery 1 according to the embodiment, the collision suppressing member 10 that suppresses the collision of the air bubble 8 with the main surface 3 a of the negative electrode 3 below the negative electrode 3, in other words, between the negative electrode 3 and the generation portion 9 I decided to provide. Specifically, the collision suppression member 10 is provided at the lower end portion 3 b of the negative electrode 3, and is configured integrally with the negative electrode 3. In addition, the collision suppressing member 10 is provided to protrude with respect to the main surface 3 a of the negative electrode 3. Here, the term “protrusing” means that both ends 10a and 10b of the collision suppressing member 10 in the direction in which the positive electrode 2 and the negative electrode 3 are arranged (that is, the Y-axis direction) are adjacent from the same plane on which the adjacent main surfaces 3a are located It represents that it arrange | positions on the positive electrode 2 side which the main surface 3a to carry out faces. Thereby, when the air bubbles 8 flowing in the electrolytic solution 6 rise in the vicinity of the lower end portion 3 b of the negative electrode 3, the air bubbles 8 can be separated from the main surface 3 a. That is, when the air bubbles 8 rise along the main surface 3 a of the negative electrode 3, collision with zinc adhering to the main surface 3 a can be suppressed. Therefore, according to the embodiment, it is possible to suppress the reduction of the coulomb efficiency and the reduction of the cycle life, and to suppress the clogging of the discharge port 9 a and the short circuit due to the conduction with the negative electrode 3 or the positive electrode 2. In the case of a battery in which the active material adheres to the positive electrode 2, the same collision suppression member may be provided on the positive electrode 2.

  Further, in the flow battery 1 according to the embodiment, oxygen generated by the electrolysis of the water in the electrolytic solution 6 may be contained in the bubbles 8. And, when the bubbles 8 containing oxygen collide with the zinc, the zinc may be oxidized and inactivated. However, in the embodiment, since the collision suppression member 10 suppresses the collision between the zinc and the air bubbles 8, it is possible to suppress the oxidation and deactivation of zinc.

  In the embodiment, the collision suppression member 10 may be formed of an insulating member such as resin. Thereby, it is possible to prevent zinc from being deposited on the surface of the collision suppressing member 10 integrally formed with the negative electrode 3 during charging. Therefore, according to the embodiment, in the collision suppression member 10, the bubbles 8 collide with the zinc deposited on the surface, and the zinc can be suppressed from dropping off. As described above, when the collision suppressing member 10 is made of resin, the collision suppressing member 10 may be formed by molding the lower end 3 b of the negative electrode 3 with resin. In this case, the surface of the lower end 3b of the negative electrode 3 may be roughened. As a result, the adhesion of the collision suppressing member 10 made of resin to the lower end portion 3b can be improved, so that the reliability of the flow battery 1 can be improved.

  Furthermore, when the lower end 3b of the negative electrode 3 is molded with resin, it is preferable to mold not only the lower end 3b of the negative electrode 3 but also both side ends of the negative electrode 3 with resin. Thereby, it can suppress that an electric current concentrates on the lower end part 3b of the negative electrode 3, and both the side end parts in the case of charge. Therefore, it can suppress that zinc concentrates and precipitates in the lower end part 3b of the negative electrode 3, and both the side end in charge.

  In the embodiment, the height at which the collision suppressing member 10 protrudes with respect to the major surface 3 a of the negative electrode 3 is, for example, 1 mm or more and 2 mm or less. However, such a projecting height can prevent the bubbles 8 from colliding with the main surface 3 a of the negative electrode 3, and allow the bubbles 8 to appropriately flow between the positive electrode 2 and the negative electrode 3 facing each other. There is no limit to the height as long as it is arranged to be able to

The collision suppression member 10 is not provided on the positive electrode 2, but is provided only on the negative electrode 3, so that the bubbles 8 floating between the positive electrode 2 and the negative electrode 3 can cause an asymmetric movement. Specifically, due to the presence of the collision suppression member 10, the bubble 8 moved to the positive electrode 2 vibrates between the direction in which the positive electrode 2 is present and the direction in which the negative electrode 3 is present at the position after movement. Movement remains. By this movement, the electrolytic solution 6 in the vicinity of the negative electrode 3 is more well stirred. Thereby, the fall of the density | concentration of [Zn (OH) ₄ ] ^2- in the vicinity of the negative electrode 3 which arises by charge can be eliminated more rapidly.

  The flow battery 1 according to the embodiment will be further described. The generator 9, the housing 17 and the upper plate 18 are made of, for example, a resin material having alkali resistance and insulation, such as polystyrene, polypropylene, polyethylene terephthalate, polytetrafluoroethylene, polyvinyl chloride and the like. The housing 17 and the upper plate 18 are preferably made of the same material as each other, but may be made of different materials. In addition, the housing 17 and the upper plate 18 may be made of the same material as the generator 9 or may be made of a different material.

  The supply unit 14 supplies the gas recovered from the inside of the housing 17 via the pipe 16 to the generator 9 via the pipe 15. The supply unit 14 is, for example, a pump (gas pump) capable of transferring gas, a compressor, or a blower. If the air tightness of the supply unit 14 is increased, the power generation performance of the flow battery 1 is unlikely to be lowered due to the gas or the water vapor derived from the electrolytic solution 6 leaking to the outside.

  Next, connection between electrodes in the flow battery 1 will be described. FIG. 2 is a view for explaining an example of connection between electrodes of the flow battery 1 according to the embodiment.

  As shown in FIG. 2, the negative electrodes 3A, 3B and 3C are connected in parallel via the tabs 3A1, 3B1 and 3C1 which the negative electrodes 3A, 3B and 3C respectively have. The positive electrodes 2A and 2B are connected in parallel via the tabs 2A1 and 2B1 of the positive electrodes 2A and 2B, respectively. By thus connecting the negative electrode 3 and the positive electrode 2 in parallel, the electrodes of the flow battery 1 can be appropriately connected and used even if the total number of the positive electrode 2 and the negative electrode 3 is different.

  In the flow battery 1 shown in FIG. 1, a total of five electrodes are configured such that the negative electrode 3 and the positive electrode 2 are alternately disposed, but the present invention is not limited thereto. Three or six or more electrodes are used. They may be alternately arranged, and one positive electrode 2 and one negative electrode 3 may be arranged. Further, in the flow battery 1 shown in FIG. 1, both ends are configured to be negative electrodes (3A, 3C). However, the present invention is not limited thereto, and both ends may be configured to be positive electrodes.

  Furthermore, the same number of negative electrodes 3 and positive electrodes 2 may be alternately arranged so that one end is the positive electrode 2 and the other end is the negative electrode 3. In such a case, the connection between the electrodes may be in parallel or in series.

<Modification>
FIG. 3 is a schematic view of a flow battery 1A according to a modification of the embodiment. The flow battery 1A shown in FIG. 3 has the same configuration as the flow battery 1 according to the embodiment except that the configuration of the collision suppressing member 10A is different.

  Similar to the embodiment, the collision suppression member 10A is provided below the negative electrode 3 and provided so as to protrude with respect to the main surface 3a of the negative electrode 3. On the other hand, unlike the embodiment, the collision suppression member 10A is configured separately from the negative electrode 3. Thus, even when the collision suppression member 10A is configured separately from the negative electrode 3, the air bubbles 8 can be separated from the main surface 3a when the air bubbles 8 rise near the lower side of the negative electrode 3. Thereby, when the air bubbles 8 rise along the main surface 3 a of the negative electrode 3, collision with zinc adhering to the main surface 3 a can be suppressed. Therefore, according to the modification, it is possible to suppress a decrease in coulomb efficiency and a decrease in cycle life, and to suppress a short circuit due to clogging of the discharge port 9 a or conduction with the negative electrode 3 or the positive electrode 2.

  The collision suppressing member 10A is held on the inner wall or the like of the housing 17 between the lower end portion 3b of the negative electrode 3 and the generating portion 9. Further, since the collision suppression member 10A is configured separately from the negative electrode 3, it may be configured of a conductive material or may be configured of an insulating material. For example, when the collision suppression member 10A is made of a conductive material, zinc which is dropped from the negative electrode 3 and attached to the collision suppression member 10A forms a local battery with the collision suppression member 10A. Then, the zinc on the collision suppressing member 10A dissolves in the electrolytic solution 6 in a short time by the corrosion reaction caused by the local current generated between the collision suppressing member 10A and the zinc. As described above, by forming the collision suppression member 10A with a conductive material, even if zinc deposited on the negative electrode 3 is dropped on the collision suppression member 10A, the zinc attached to the collision suppression member 10A is dissolved. Thus, the negative electrode active material can be contributed to the charge reaction. When the collision suppressing member 10A is made of a conductive material, the collision suppressing member 10A may be made of the same material as that of the negative electrode 3 or may be made of a material different from that of the negative electrode 3.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning. For example, in the embodiment described above, an example in which the collision suppression member 10 or the collision suppression member 10A is provided is shown, but both the collision suppression member 10 and the collision suppression member 10A may be provided.

  Further, in the above-described embodiment, the powder 7 is described as being mixed in the electrolytic solution 6, but the present invention is not limited to this, and the powder 7 may not be included. In such a case, it is preferable to increase the amount of the negative electrode active material contained in the negative electrode 3.

  In the above-described embodiment, the diaphragms 4 and 5 are described as being disposed so as to sandwich the both sides in the thickness direction of the positive electrode 2. However, the present invention is not limited thereto, and may be disposed between the positive electrode 2 and the negative electrode 3 In addition, the positive electrode 2 may be coated.

  Although the supply unit 14 may be operated at all times, from the viewpoint of reducing power consumption, the supply rate of gas may be reduced during discharge rather than during charge.

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

1, 1A flow battery 2, 2A, 2B positive electrode 3, 3A, 3B, 3C negative electrode 4, 5 diaphragm 6 electrolyte 7 powder 8 bubble 9 generation part 9a discharge port 10, 10A collision suppression member 14 supply part 17 case 18 top Board

Claims (7)

Positive electrode and negative electrode,
An electrolytic solution contacting the positive electrode and the negative electrode;
A flow device including a generator for generating bubbles in the electrolytic solution and flowing the electrolytic solution;
And a collision suppressing member provided to protrude to a main surface of the positive electrode or the negative electrode below at least one of the positive electrode and the negative electrode.   The flow battery according to claim 1, wherein the collision suppressing member is made of an insulating material, and is integrally formed with the negative electrode.   The flow battery according to claim 1, wherein the collision suppression member is configured separately from the negative electrode. The negative electrode includes a first negative electrode and a second negative electrode facing each other with the positive electrode interposed therebetween,
The air bubbles float between the first negative electrode and the positive electrode, and between the positive electrode and the second negative electrode.
The electrolytic solution descends between a first inner wall and a first negative electrode of a case containing the electrolytic solution, and between a second inner wall of the case facing the first inner wall and the second negative electrode. The flow battery according to any one of claims 1 to 3, wherein:   The flow battery according to any one of claims 1 to 4, wherein the collision suppression member is provided only on one of the positive electrode and the negative electrode.   The flow battery according to any one of claims 1 to 5, wherein the collision suppressing member is provided on the negative electrode. The flow battery according to any one of claims 1 to 6, further comprising: a powder containing zinc and movably mixed in the electrolytic solution.

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