flow battery

Abstract

The present invention takes into consideration the drawbacks of conventional cell stack structures and aims to provide an improved flow battery, typically an RF battery. [Solution] The flow battery of the present invention has a cell stack constructed from multiple insertable and removable cell cartridges, and each cell cartridge is composed of multiple cells, and each cell is connected between electrodes with low resistance by a small binding force, and electrolyte leakage is prevented. The flow battery of the present invention also includes multiple cell cartridges and a backplane to which the multiple cell cartridges are physically attached so that they can be inserted and removed side by side with gaps between them, and a rack or unit on which multiple backplanes are mounted, and a removable electrolyte tank, which allows the output and capacity of the flow battery to be freely designed and changed according to demand.

Description

[Technical Field]

[0001] The present invention relates to a flow battery, typically a redox flow battery (hereinafter referred to as an "RF battery"). [Background technology]

[0002] Flow batteries will be explained below using RF batteries as an example. The use of renewable energy sources such as solar and wind power is being promoted. However, the output of solar and wind power generation fluctuates depending on the time of day, weather, and the environment, so when they are introduced into the power grid, they can disrupt the grid (deteriorating power quality).

[0003] Therefore, RF batteries are attracting attention as a type of energy storage battery (secondary battery), which is a key technology for stabilizing the power grid. Compared to other secondary batteries, RF batteries have excellent features such as a long life, large capacity, and safety.

[0004] FIG. 1 is a diagram illustrating the basic structure of a conventional RF battery. Essentially, an RF battery 100 is composed of a cell stack 101 located in the center, and a positive electrode liquid tank 102t and a positive electrode liquid feed pump 102p, and an negative electrode liquid tank 103t and a negative electrode liquid feed pump 103p, which are installed on either side of the cell stack 101. The positive electrode liquid feed pump 102p circulates the positive electrode liquid stored in the positive electrode liquid tank 102t through piping as shown by the solid lines. Similarly, the negative electrode liquid feed pump 103p circulates the negative electrode liquid stored in the negative electrode liquid tank 103t through piping as shown by the dashed lines.

[0005] The cell stack 101 has a cell stack structure in which many battery cells 104 are stacked. Each battery cell 104 includes two cell frames 104sf and is sandwiched between two electrode plates 104bp. A negative electrode 104ne, a separator 104se, and a positive electrode 104pe are arranged between the two cell frames 104sf. The stacked battery cells 104 are sandwiched between electrode plates 108 on both sides and are further sandwiched between end plates 105 on both sides. The end plates 105 on both sides are tightly fastened along their peripheries with fastening members (bolts and nuts) 106. A sealant 107 is placed along the edge of the cell frames between the two cell frames 104sf of each battery cell to seal against leakage of the electrolyte (positive electrode solution, negative electrode solution). The cell stack structure is formed by tightly fastening and integrating many battery cells 104 with the end plates 105 and fastening members 106.

[0006] This cell stack structure is a simple stack of battery cells, and the mechanism for sending and returning the electrolyte to the battery cells is also relatively simple. As a result, RF batteries with a cell stack structure have a relatively small number of parts, and material costs, manufacturing costs, etc. are relatively low. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] WO 2020 / 218418 A1 "Bipolar plate, battery cell, cell stack, and redox flow battery" [Patent Document 2] Patent Publication No. 2020-087836 "Bipolar plate for battery, manufacturing method for bipolar plate for battery, and redox flow battery" [Patent Document 3] Patent Publication No. 2022-526449 "Porous silicon film material, its production, and electronic devices incorporating the same" [Patent Document 4] Patent Publication 2002-015762 "Redox flow battery" [Patent Document 5] Patent Publication No. 2020-184406 "Method of operating a redox flow battery and a redox flow battery" [Patent Document 6] WO 2019 / 087377 "Redox flow battery" [Patent Document 7] Patent No. 5585311 "Battery Management System" [Patent Document 8] Patent No. 5916819 "Electric energy transportation system" Summary of the Invention [Problem to be solved by the invention]

[0008] Although the cell stack structure RF battery has the advantages mentioned above, it also has the following disadvantages. (1) The end plates, fastening members, etc. are relatively heavy, making the weight of the entire cell stack very heavy. (2) Because the fastening bolts are relatively long, they can stretch over time or due to temperature changes, which can cause the sealing material between the battery cells to lose its effectiveness and pose a risk of electrolyte leakage. (3) When a battery cell fails, it is difficult to remove the failed battery cell from the integrated cell stack structure and repair or replace it on site.

[0009] The present invention takes into consideration the drawbacks of these cell stack structures and aims to provide an improved flow battery, typically an RF battery. [Means for solving the problem]

[0010] In one aspect, the flow battery of the present invention comprises N cell cartridges (N is an integer of 1 or greater) and a backplane having N or more mounting spaces, on which the cell cartridges can be physically and detachably mounted side by side in the mounting spaces with gaps between them.

[0011] In the flow battery described above, the backplane may further include a positive electrode liquid outgoing channel and a positive electrode liquid return channel that connect to each of the cell cartridges, and couplers provided at each connection location, and a negative electrode liquid outgoing channel, a negative electrode liquid return channel, and couplers provided at each connection location, thereby ensuring the flow of positive and negative electrolytes to the cell cartridges attached to the backplane.

[0012] The flow battery may further include a rack frame, and the backplanes in multiple stages may be attached to the rack frame, and a positive and negative electrolyte outward connecting pipe and a positive and negative electrolyte return connecting pipe attached to the rack frame may be connected to a positive and negative electrolyte outward channel and a positive and negative electrolyte return channel attached to each of the backplanes via a coupler, respectively, thereby ensuring the flow of positive and negative electrolytes to each of the backplanes.

[0013] In the flow battery, the coupler may be a coupler with an electrolyte leakage prevention function, and the backplane or the cell cartridge may be replaceable without electrolyte leakage.

[0014] In the above-described flow battery, the cell cartridge has any desired number of stacked cells, and the cells are formed by stacking at least both electrode plates and / or one electrode plate and one separator out of both electrode plates, a separator, and one electrode plate as constituent parts, and some or all of the cell cartridge constituent parts may be fixed to each other.

[0015] The flow battery may further include a heat exchange component that exchanges heat by blowing air into gaps between the plurality of cell cartridges.

[0016] In the above flow battery, the backplane may further include a diode functional component connected in parallel to each of the cell cartridges so that the anode is connected to the negative electrode of the cartridge and the cathode is connected to the positive electrode of the cartridge, thereby preventing an excessive reverse voltage from being applied to the backplane when a faulty cell cartridge is removed during operation.

[0017] In the above flow battery, a sensor capable of measuring the voltage of each cell constituting the cell cartridge may further be incorporated into the backplane.

[0018] In the above flow battery, the backplane may further include a sensor that can measure at least one of the voltage of each cell that constitutes the cell cartridge, and the flow rate, temperature, pressure, or oxidation-reduction potential of the positive and negative electrode solutions.

[0019] In the flow battery described above, an electrolyte flow rate adjustment valve may further be incorporated in each of the positive electrode liquid outflow channel and the negative electrode liquid outflow channel of the backplane.

[0020] The flow battery may further include an RF main unit, a plurality of positive electrode liquid tanks, and a plurality of negative electrode liquid tanks, wherein the backplane and the forward and return channels are attached to the RF main unit in a plurality of stages, and one or more pairs of leak prevention couplers are attached to one pair of the positive electrode liquid forward channel and the positive electrode liquid return channel, and one or more pairs of leak prevention couplers are attached to one pair of the negative electrode liquid forward channel and the negative electrode liquid return channel, thereby connecting or disconnecting any number of electrolyte tanks and piping via the couplers, and enabling the increase or decrease of the electrolyte to be charged or discharged, and the exchange of the electrolyte after charging and the electrolyte after discharging.

[0021] In one aspect of the flow battery according to the present invention, the battery section comprises a stack having any number of cells, and the cells are constituted by appropriately stacking at least both electrode plates and / or one electrode plate and one separator out of two electrode plates, a separator, and one electrode plate as constituent parts, and the two electrode plates or one electrode plate are fixed (adhered or welded) to form an integrated unit, or adjacent constituent parts are fixed (adhered or welded) to each other to form an integrated unit.

[0022] In the flow battery, the stack may be integrated by fixing (adhering or welding) adjacent cells to each other.

[0023] In the flow battery, the cell may be applied to either a battery cell having a cell stack structure or a cell battery having the cell cartridge-backplane structure. [Effects of the Invention]

[0024] According to the present invention, it is possible to provide an improved flow battery, typically an RF battery, which compensates for the drawbacks of the cell stack structure. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a diagram illustrating the basic structure of a conventional RF battery. [Figure 2] FIG. 2 shows an example of a cell cartridge module constituting the RF battery according to the first embodiment. [Figure 3] Figure 3 shows four cell cartridge modules mounted vertically on a rack frame. [Figure 4] FIG. 4 is a diagram showing a cell cartridge. [Figure 5A] FIG. 5A, together with FIG. 5B, is an overall view of the RF battery according to this embodiment. [Figure 5B] FIG. 5B, together with FIG. 5A, is an overall view of the RF battery according to this embodiment. [Figure 6] Figure 6 shows an example of a cell cartridge made with one electrode plate and two electrode plates. [Figure 7] FIG. 7 shows an example of the configuration of both electrode plates realized by conductive impermeable sheets. [Figure 8A] FIG. 8A, together with FIG. 8B, shows an electrolyte coupler with a leak-proof valve. [Figure 8B] FIG. 8B, together with FIG. 8A, shows an electrolyte coupler with a leak-proof valve. [Figure 9] Figure 9 shows the electrical structure and wiring diagram of the backplane and cell cartridge. [Figure 10] Figure 10 shows an example in which the functions required for managing and controlling the cartridge module are incorporated into the backplane. [Figure 11] FIG. 11 is a block diagram of a multi-sense control communication board integrated into a backplane. [Figure 12] FIG. 12 shows an example of a system in which the anode and cathode electrolyte tanks can be separated in an RF battery. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, an embodiment of a flow battery according to the present invention will be described in detail with reference to the accompanying drawings, taking an RF battery as an example. In the drawings, the same elements are given the same reference numerals, and redundant explanations will be omitted.

[0027] [First embodiment] 2 shows an example of a cell cartridge module 12 constituting the RF battery 10 (see FIG. 5A) according to the first embodiment. (a) is a front view of the cell cartridge module, and (b) is an AA cross-sectional view thereof.

[0028] The RF battery 10 according to the first embodiment employs a cell cartridge-backplane structure (the structure of a cell cartridge module 12) in place of the stack structure of the cell stack 101 of the RF battery shown in Fig. 1. The cell cartridges 11 are mounted with gaps between them.

[0029] Below, we will explain the structure of the cell cartridge module that realizes the cell cartridge-backplane structure, the detailed structure of the cell cartridge, and the overall configuration of the RF battery realized by the cell cartridge module.

[0030] (Structure of cell cartridge module) As shown in the front view of FIG. 2(a), in the cell cartridge module 12, three cell cartridges 11 are attached to the backplane 13 using cartridge fixing bolts 151. The backplane 13 is attached to the horizontal square pipe 14 using backplane fixing bolts 152. The horizontal square pipe 14 is fixed to the rack frame 15 (see FIG. 3) in advance. Although the number of cell cartridges 11 attached to the backplane 13 is three in FIG. 2, any desired number may be used. The mounting area of ​​the backplane 13 may be provided to accommodate more than the actual number of cell cartridges 11.

[0031] Each cell cartridge 11 is provided with electrolyte couplers 33, 34 at the inlet and outlet for the electrolyte to flow in. The electrolyte passing through the interior of each cell cartridge 11 is separated into a positive electrode route and a negative electrode route. For this reason, elements of the positive electrode route are distinguished by adding a "p" to the reference symbol, and elements of the negative electrode route are distinguished by adding an "n" to the reference symbol.

[0032] Positive electrode liquid (shown by a solid line) supplied from tank 36t (see FIG. 5A) is diverted from positive electrode liquid outflow channel 17p by electrolyte coupler 33p provided in each cell cartridge unit, and is supplied to positive electrode 1045 of the cell constituting the cell cartridge. The electrolyte that has reacted at positive electrode 1045 joins at positive electrode liquid return channel 19p from electrolyte coupler 34p and is returned to tank 36t. The same is true for negative electrode liquid (shown by a dashed line).

[0033] The electrolyte coupler 33p is provided with a convex insertion / removal coupler (hereinafter referred to as "plug") 331p on the cell cartridge 11 side, and a concave receiving coupler (hereinafter referred to as "socket") 332p on the backplane side. The plug and socket are connected via an O-ring 333p. The mechanism (plug, socket, and O-ring) of the electrolyte coupler 34p is similar. Insertion and removal are possible due to the mechanism of the plug 331p and socket 332p. The mechanism of the electrolyte coupler 33n and electrolyte coupler 34n for the negative electrode route is also similar.

[0034] The cell cartridge 11 is connected to the backplane side via an electrolyte coupler. If the electrolyte coupler is a coupler with a leakage prevention function, electrolyte leakage will not occur even when the cell cartridge 11 is attached to or detached from the backplane during operation. The leakage prevention mechanism of such an electrolyte coupler will be described in detail with reference to Figures 8A and 8B.

[0035] Compared to the integrated cell stack structure shown in FIG. 1, the cell cartridge module 12 shown in FIG. 2 has gaps (preferably 1 to 50 mm) between the cell cartridges, allowing them to be attached to and detached from the backplane 13. As a result, the cell cartridges 11 can be handled individually. That is, each cell cartridge is small and lightweight, making transportation, installation, replacement, maintenance, and the like easy. Furthermore, heat generated in each cell cartridge 11 can be efficiently released to the outside by forced air cooling, utilizing the gaps between them. If necessary, warm air can be blown into these gaps to heat each cell cartridge 11.

[0036] 3 shows four vertically arranged cell cartridge modules 12 mounted on a rack frame 15. (a) is a front view with the front panel removed, and (b) is a cross-sectional view taken along the line AA.

[0037] A cooling fan 22 is installed on the upper stage of the rack frame 15. Four sets of horizontal square pipes 14, two at the top and two at the bottom, are pre-attached to the rack frame 15, allowing four sets of cell cartridge modules 12 to be fixed.

[0038] The symbols shown in (b) are as follows: PF: forward path positive electrode liquid, PR: return path positive electrode liquid, NF: forward path negative electrode liquid, NR: return path negative electrode liquid.

[0039] The positive electrode liquid PF from the positive electrode liquid forward connecting pipe 18p at the bottom of the rack frame is divided into the positive electrode liquid forward channels 17p of the four cell cartridge modules 12. The positive electrode liquid PR from the positive electrode liquid return channels 19p of the cell cartridge modules is combined into one and joins the positive electrode liquid return connecting pipe 20p at the top of the rack frame. Similarly, the negative electrode liquid is divided into the negative electrode liquid forward channel 17n of each cell cartridge module, and the negative electrode liquid NR from the negative electrode liquid return channel 19n of the cell cartridge module joins the negative electrode liquid return connecting pipe 20n.

[0040] The rack frames can be easily connected together and installed in large enclosures such as containers.

[0041] (Detailed structure of the cell cartridge) 4 is a diagram showing the cell cartridge 11. Here, (a) is a front view of the cell cartridge 11, (b) is a left side view, and (c) is an AA cross-sectional view.

[0042] The cell cartridge 11 can be constructed by stacking any number of cells 28. In the illustrated example, as shown in (b), it is constructed from two cells 28. This cell cartridge 11 is constructed with one electrode plate 121 sandwiched between two separators 122 and two single electrode plates 123, and is fastened with fastening members (insulating bushings 124 and fastening screws 125). In general, the cell cartridge 11 can be constructed by stacking any number N of cells, and in this case, it is constructed from N-1 electrode plates, N separators, and two single electrode plates.

[0043] As shown in (a) and (b), the cell cartridge 11 is provided with two electrolyte couplers 33, 34, one above the other and one below the cell body. The lower electrolyte coupler 33 has protrusions (plugs) that couple to the positive electrode liquid outflow channel 17p and the negative electrode liquid outflow channel 17n of the backplane 13, and the upper electrolyte coupler 34 has protrusions (plugs) that couple to the positive electrode liquid return channel 19p and the negative electrode liquid return channel 19n of the backplane 13. By attaching the cell cartridge to the backplane, the flow of electrolyte is ensured.

[0044] As shown in (a) and (b), the positive electrode liquid / negative electrode liquid sent from the outgoing channels 17p / 17n is supplied to the lower electrolyte coupler 33, where it is divided into the positive electrode / negative electrode of the cell mounted in the cell cartridge, passes through the positive electrode / negative electrode, respectively, joins at the upper electrolyte coupler 34, and is discharged to the return channel 19p / 19n. The cell cartridge 11 can be attached to and detached from the backplane by the electrolyte couplers 33 and 34.

[0045] (Overall configuration of RF battery) 5A and 5B are overall views of the RF battery according to this embodiment. Fig. 5A shows the battery section. Fig. 5B (a) shows the control section, and (b) shows the power conversion section.

[0046] 5A , the negative electrode liquid in the negative electrode liquid tank 35t is delivered by the negative electrode liquid pump 35p, passes through the outgoing piping 35f to be supplied to the cartridge module 12, passes through the inside of the cell cartridge 11 and returns to the tank 35t through the return piping 35r. Similarly, the positive electrode liquid in the positive electrode liquid tank 36t is delivered by the positive electrode liquid pump 36p, passes through the outgoing piping 36f to be supplied to the cartridge module 12, passes through the inside of the cell cartridge 11 and returns to the tank 36t through the return piping 36r.

[0047] The control unit in Fig. 5B (a) is composed of a system controller 40 that controls the operation of the RF battery. The power conversion unit in (b) is composed of an inverter (DC → AC converter) 41 that converts the output of the battery unit to the system (100V or 200V AC) and a charger (AC → DC converter) 42 that charges the battery from the system.

[0048] The system controller 40 controls the inverter 41 and the charger 42 so that the RF battery can be charged from the power grid or power can be supplied from the RF battery to the power grid according to demand. Such control can be applied to power grid power leveling, uninterruptible power supplies, etc.

[0049] In addition, the system controller 40 monitors each signal and performs various controls. For example, during charging and discharging, the system controller 40 controls the charger 42 or inverter 41 so that each cell does not experience an overcurrent, overcharge, or overdischarge. Input monitoring signals include the voltage (v0 to vN) 401 of each battery cell, positive electrode liquid level meter value 402, positive electrode liquid oxidation-reduction potentiometer value 403, negative electrode liquid level meter value 404, negative electrode liquid oxidation-reduction potentiometer value 405, positive electrode liquid thermometer value 406, negative electrode liquid thermometer value 407, etc. Output control signals include a positive electrode liquid pump control output 408, a negative electrode liquid pump control output 409, a cooling fan rotation control output 410, an inverter control output 411, a charger control output 412, an alarm transmission output 413, etc.

[0050] The technical matters explained in the RF battery according to the first embodiment are also common to the second and subsequent embodiments.

[0051] [Second embodiment] (composition) In the second embodiment, a specific example of the cell cartridge 11 will be described. Fig. 6 shows the cell cartridge 11 composed of one electrode plate and both electrode plates. (a) shows one electrode plate 123, (b) shows the configuration of both electrode plates 121, and (c) shows the assembled cell cartridge 11. Here, the electrolyte couplers 33 and 34 are not shown.

[0052] As shown in (a), one electrode plate 123 is composed of a flanged conductive plate 1231, a conductive sealing material 1232, a highly chemical-resistant conductive adhesive 1233, a reactive electrode material 1234, and a resin frame plate 1235.

[0053] The conductive plate 1231 is made of a metal with high conductivity (copper, aluminum, etc.). The conductive sealant 1232 is made of a highly conductive material (carbon sheet, etc.) that is impermeable to electrolyte and highly resistant to chemicals. The reactive electrode material 1234 is made of carbon fiber felt, cloth, etc. The resin frame plate 1235 is made of a highly chemical-resistant resin (vinyl chloride, polyethylene, polypropylene, etc.). As shown in the figure, the resin frame plate 1235 has a frame-like shape with a hollowed-out area for the reactive electrode material, and has an electrolyte return groove 1217 at the top and an electrolyte forward groove 1216 at the bottom. The conductive sealant 1232, reactive electrode material 1234, and resin frame plate 1235 are pressed together and bonded with a conductive adhesive 1233.

[0054] As shown in (b), both electrode plates 121 are composed of a conductive plate 1211 in the center, a conductive seal material 1212, a highly chemical-resistant conductive adhesive 1213, a reactive electrode material 1234, and a resin frame plate 1215. The materials are the same as those described above, but the resin frame plate 1215 has an O-ring groove 1236 carved therein in addition to the resin frame plate 1235 of one electrode, as shown in the figure. As with the single electrode plate 123, in both electrode plates 121, the conductive seal material 1212, reactive electrode material 1234, and resin frame plate 1215 are pressed together and bonded with the conductive adhesive 1213.

[0055] As shown in (c), the cell cartridge 11 is configured with one double electrode plate 121, two single electrode plates 123, two separators 122, and two O-rings 126, which are fastened together by a fastening screw 127, an insulating bushing 128, a washer 129, and a nut 130. An ion-permeable membrane is typically used for the separator 122.

[0056] (operation) The gap between one electrode plate 123 and both electrode plates 121 that make up the cell cartridge 11 is sealed by an O-ring 126. Therefore, the electrolyte supplied from the electrolyte outflow port 1216 does not leak to the outside of the cells 28, and is entirely discharged from the electrolyte return port 1217. Because the cell cartridge 11 is tightly bound by a relatively small number of cells 28, it is less susceptible to the effects of loosening or stretching of the screws due to changes over time or temperature, and therefore the risk of electrolyte leakage from the cells can be reduced.

[0057] Furthermore, conventionally, a binding method has been used to connect the reactive electrode material, conductive sealant, and conductive plate with low contact resistance. However, in this embodiment, these are pressure-bonded using a low-resistance, highly chemical-resistant conductive adhesive, so there is no need to bind the cell 28 with strong pressure. Because one electrode plate 123 is supported by a metal conductive plate, the cell cartridge 11 can maintain sufficient strength against pressure fluctuations and vibrations of the electrolyte.

[0058] Although not shown, the conductive plate 1231 may be provided with fins to improve heat exchange efficiency.

[0059] [Third embodiment] (composition) In the third embodiment, another specific example of the cell cartridge 11 will be described. FIG. 7 shows an example of the configuration of both electrode plates 43 realized by using an electrically non-conductive sheet 431. (a) is an external view of both electrode plates 43, (b) is a structural diagram of both electrode plates 43, and (c) is an example of a cell cartridge using both electrode plates 43. As shown in (b), both electrode plates 43 are composed of an electrically non-conductive sheet 431, two reactive electrode materials 433, and two resin-framed sheets 432. Although not shown, one electrode plate can easily be composed of an electrically non-conductive sheet 431, one reactive electrode material 433, and one resin-framed sheet 432. The cell cartridge 11 in (c) is stacked with a separator sandwiched between both electrode plates 43, and the resin-framed sheets are bonded together by bonding, welding, or the like. In the illustrated example, the cell cartridge 11 is realized only by both electrode plates 43.

[0060] (operation) The electrode plates 43 shown in Fig. 7(a) can be realized by the configuration shown in Fig. 7(b) using a conductive impermeable sheet 431. The conductive impermeable sheet 431 is a sheet that maintains high conductivity while preventing permeation of the electrolyte and has mechanical strength. For example, the conductive impermeable sheet can be made of low-resistance carbon fiber reinforced plastics (CFRP) processed into a sheet shape.

[0061] It is desirable to use a highly chemical-resistant resin kneaded with a highly conductive filler for the CFRP resin to achieve low resistance. Also, the reaction electrode junction of the CFRP sheet may be in any shape, such as a corrugated plate, a perforated pipe, or a perforated cardboard box, to improve the flow of the electrolyte.

[0062] By using the conductive impermeable sheet 431, it is possible to reduce the joint resistance between the reaction electrodes and to prepare a pair of electrode plates or a single electrode plate that is resistant to corrosion by the electrolyte for a long period of time.

[0063] According to this embodiment, the electrode plates have a simpler configuration than the electrode plates 121 shown in FIG. 6(b), allowing for a reduction in the number of parts and weight reduction because the resin frame plate can be made into a sheet. Furthermore, the manufacturing process can be simplified because the reactive electrodes can be bonded simultaneously when the conductive impermeable sheet is produced. Furthermore, by bonding the periphery of the resin frame sheet, the O-rings and screws used in FIG. 6(b) can be eliminated.

[0064] [Fourth embodiment] (composition) In the electrolyte couplers 33 and 34, the plug of the cell cartridge 11 is connected to the socket of the backplane 13 via an electrolyte coupler with a leak prevention valve, thereby enabling the cell cartridge 11 to be inserted into and removed from the backplane 13 without electrolyte leakage (see Figure 2). 8A and 8B show an example of an electrolyte coupler with a leak prevention valve, in which a socket 441 is incorporated on the backplane side and a plug 442 is incorporated on the cell cartridge side.

[0065] (operation) The function of the electrolyte coupler with a leak prevention valve will be explained with reference to Figures 8A and 8B. Here, the flow of electrolyte is represented by a thick line. The black circle at the end of the thick line indicates that the flow of electrolyte is blocked.

[0066] 8(a) shows the state before the cell cartridge 12 is inserted. Due to the pressing forces of the coil springs 443, 444 of both the socket 441 and the plug 442, the electrolyte in the forward channel and the electrolyte in the cell cartridge are both blocked by the leak prevention O-ring 126 and do not leak. In the process of pushing the cell cartridge into the backplane 13 in the direction of the arrow in the figure, as shown in (b), the electrolyte does not leak, as in (a), until the rods (protrusions) 441p, 442p, which are still in the center of the two, come into contact. As shown in (c), when the protrusion 442p of the plug 442 of the cell cartridge 11 contacts the protrusion 441p of the leakage prevention valve of the channel but the two main bodies are separated, the O-ring 126 of the plug or socket opens (the figure shows the O-ring 126 of the plug 442 in an open state), but leakage is prevented by the O-ring 127 for the coupling seal.

[0067] As shown in (d), when the two main body parts are inserted until they come into contact, the insertion force overcomes the pressing force of the two coil springs 443, 444, and the O-rings 126 of both the plug 442 and the socket 441 open, allowing the electrolyte in the forward channel to be delivered to the cell cartridge.

[0068] Conversely, when the cell cartridge is pulled out from the backplane 13, the operation proceeds in the reverse order of (d) → (c) → (b) → (a). In this case too, the electrolyte does not leak.

[0069] In a cell cartridge module equipped with this electrolyte coupler mechanism, the cell cartridge can be inserted into and removed from the backplane 13 without leakage of the electrolyte, even while the electrolyte is circulating.

[0070] [Fifth embodiment] (composition) In the fourth embodiment, it was explained that the cell cartridge 11 can be inserted into and removed from the backplane 13 even in an operating RF battery.

[0071] FIG. 9 shows the electrical structure and wiring diagram of the backplane 13 and cell cartridge 11. Three cell cartridges 11-1, 11-2, and 11-3 can be attached to the backplane 13. As shown in the left side view of FIG. 9(a), the backplane 13 has an insulating plate 45 attached to a base plate 46, and an electrode connecting plate (copper plate) 47 attached to the insulating plate 45. V0 to V6 are terminal patterns on the backplane, and V0, V2, V4, and V6 are connected to the electrode connecting plate 47. Furthermore, the potentials of V0 to V6 are sent to the system controller 40 via a voltage measurement and communication board 49.

[0072] In this example, as shown in the front view of (b), the electrode connecting plate 47 is arranged to connect the cartridges 11 in series. Note that the wiring by the electrode connecting plate 47 may also be wired in parallel. The electrode connecting plate 47 on the outside of the backplane 13 is provided with electrode connecting screw holes 471 for connecting modules, which are used to screw in cables for connecting cartridge modules in series / parallel.

[0073] Furthermore, a plate spring contact 48 is attached to the insulating plate 45, and when the cell cartridge 11 is attached to the backplane 13 and fastened with the cartridge fixing bolt (screw hole 472), the plate spring contact 48 comes into contact with the conductive plate 1211 in Figure 6(b) and the conductive impermeable sheet 431 in Figure 7(b) of both electrode plates of the cell cartridge, thereby enabling the potential of the electrodes to be detected.

[0074] As shown in the figure, diodes D1, D2, and D3 are connected on the backplane 13 between V0 and V2, V2 and V4, and V4 and V6, respectively.

[0075] (operation) When the cell cartridge 11 is inserted into the backplane 13 and the conductive plate flange is fastened to the cartridge fixing hole 472 of the backplane 13 with the cartridge fixing bolt 151, the conductive plate 1231 of one electrode plate of the cell cartridge 11 is coupled with the electrode connecting plate 47, and the leaf spring contact 48 comes into contact with the conductive plates 1211 of both electrode plates of the cell cartridge or the conductive impermeable sheet 431. This allows the terminals of all the cells that make up the cell cartridges 1 to 3 mounted in the cartridge module to be connected to the V0 to V6 terminal patterns on the backplane, connecting the cell cartridges 1 to 3 in series.

[0076] Diodes D1 to D3 are connected in parallel to each cell. If all cartridges are filled with electrolyte so that the left side of the diagram is negative and the right side is positive, then in each cartridge, the negative electrode of the cell is connected to the anode of the diode, and the positive electrode of the cell is connected to the cathode of the diode. In this state, a reverse voltage is applied to the diode, so only a very small leakage current flows.

[0077] If a faulty cell cartridge is removed during operation, without a diode, excessive reverse voltage may be applied to the corresponding backplane terminal. With D1-D3, if such a reverse voltage is applied, forward current flows through the diode, so only a few volts are applied between the terminals. This allows safe insertion and removal of cell cartridges. However, with large cells, inserting or removing them during operation can result in currents of several hundred amperes, which may cause sparks, welding of the terminals, or diode destruction. It is recommended to insert or remove the cell when power generation is stopped. Ideal diodes can also be used to improve diode characteristics.

[0078] [Sixth embodiment] The sixth embodiment is a diagram illustrating an example in which the operation of an RF battery in operation is further maintained appropriately and safety is improved.

[0079] (composition) 10 shows an example in which the functions required for managing and controlling the modules of an RF battery 10 are incorporated into the backplane 13. In this example, electrolyte flow control valves 53 and 54, electrolyte flow meters 55 and 56, electrolyte pressure gauges 57 and 58, and electrolyte thermometers 59 and 61 are installed for each positive and negative electrode as controllers for managing the electrolyte. A multi-sense control communication board 51 is installed to measure and control these.

[0080] To improve the workability of manufacturing and maintenance, a connection nipple (a pair of connection joints with a male and female thread) or coupler 60 is attached to the connection point of the electrolyte outgoing / returning route. The connection nipple / coupler 60 is connected to the electrolyte outgoing / returning connecting pipes 18p, 18n / 20p, 20n of the rack by a hose or the like, as shown in Figure 3.

[0081] (operation) 11 is a block diagram of the multi-sense control communication board incorporated into the backplane 13. The multi-sense control communication board 51 has the functions of reading all cell voltages in the backplane and the signals of the above sensors using a microprocessor 52, controlling the positive and negative electrode liquid flow rate adjustment valves, and communicating with a higher-level host computer via an insulated communication circuit 54.

[0082] Input signals to the microprocessor 52 include the voltages (v0 to vN) 521 of each battery cell, a cathode liquid pressure gauge value 522, a cathode liquid flow rate meter value 523, a cathode liquid thermometer value 524, anode liquid pressure gauge value 525, anode liquid flow rate meter value 526, anode liquid thermometer value 527, and a drive power supply 528 from a power supply 532 via an insulated power supply 529. Output signals include a cathode liquid flow rate adjustment valve control output 530 and an anode liquid flow rate adjustment valve control output 531. This allows the microprocessor 52 to appropriately maintain the anode / cathode liquid flow rates in the battery cells, measure and manage the pressures of the anode and cathode electrolytes, and control the temperature of the electrolyte to be constant. Furthermore, when replacing a faulty cell cartridge, the entire module can be stopped by closing the cathode / cathode liquid flow rate adjustment valves 53 and 54, allowing the cell cartridge to be replaced safely.

[0083] This microprocessor 52 manages and controls each backplane, and a host computer manages and controls multiple backplanes.

[0084] [Seventh embodiment] (composition) 12 shows an example of a system in which an RF main unit 62 is used in an RF battery 10, and an anode liquid tank 35t and a cathode liquid tank 36t can be separated from the RF main unit 62. The RF main unit 62 is composed of a plurality of cartridge modules or a plurality of rack frames, a liquid transfer pump, piping, etc., and is a unit that has the function of converting electrical energy and chemical energy into each other.

[0085] The RF main unit 62 is detachably connected to the negative electrode liquid tank 35t and the positive electrode liquid tank 36t by one or more pairs of couplers 44 with anti-leak valves for the positive and negative electrolytes, respectively (see FIGS. 8A and 8B). Furthermore, a shutoff valve 50 may be installed to prevent the electrolyte from leaking in the event of an abnormality. By providing two or more pairs of couplers with anti-leak valves, the electrolyte tanks can be replaced without stopping the charging / discharging operation, even during operation.

[0086] The structure allows the negative electrode liquid tank 35t and the positive electrode liquid tank 36t to be separated from the RF main unit 62, making it possible to replace or transport the electrolyte and to increase or decrease the electrolyte capacity. In addition, increasing or decreasing the RF main unit 62 also makes it easy to change the input or output power.

[0087] Conventionally, RF batteries could only be constructed with systems with a predetermined power output (W) and maximum storage capacity (Wh). However, in this embodiment, the RF main unit mechanism makes it possible to appropriately increase or decrease the output and storage capacity according to demand, share power between systems, and perform maintenance without shutting down the entire system. By parking multiple RF main units 62 and multiple tanks 35t and 36t, it is easy to expand to a battery with a huge capacity.

[0088] [Advantages and effects of this embodiment] According to the RF battery with the cell cartridge-backplane structure and RF core unit mechanism of this embodiment, design, installation, maintenance, replacement, etc. can be performed on a cell cartridge, cartridge module, RF core unit, and electrolyte tank basis, which is expected to provide the following advantages and effects.

[0089] (1) The cell cartridge structure enables weight reduction, fewer parts, and fewer manufacturing processes than conventional stack structures, and as a result, the following effects can be expected over the life cycle. (a) At the design stage, the number of cell cartridges and cartridge modules required, the amount of RF core units and electrolyte, and the number of electrolyte tanks can be easily determined to meet the desired power conditions of the RF battery (output voltage, output power, storage capacity, etc.). (b) During manufacturing, cell cartridges can be standardized, which allows for mass production and automation to reduce manufacturing costs. Even for large-scale RF batteries, prefabrication of the RF core unit and electrolyte tanks can reduce costs and shorten construction times. (c) In the inspection process, testing and evaluation can be easily performed on a cell cartridge basis, avoiding the large amount of rework (disassembly, repair, reassembly, and re-inspection) that previously occurred when a stack malfunctioned. (d) During installation, the cartridge module can be installed individually, making it easy to install in small spaces. (e) By stocking cell cartridges as maintenance parts, it becomes possible to quickly replace a cell cartridge in the event of a malfunction.

[0090] (2) The RF core unit equipped with multiple pairs of couplers with leak prevention valves makes it easy to replace electrolyte tanks, increase or decrease the number of electrolyte tanks, or transport them during operation.

[0091] [Variations and Others] The RF battery according to this embodiment can be applied not only to various redox flow batteries but also to devices including stacked cells (for example, fuel cells and electrolysis elements).

[0092] For example, in a device having cells in a stack configuration, the stack may include any number of cells, and each cell may have, as components, both electrode plates, a separator, and one electrode plate, and the adjacent components may be partly or entirely fixed (adhered or welded) to each other to form an integrated unit. Furthermore, the cells may be fixed (adhered or welded) to each other.

[0093] It can also be applied to flow batteries that use only one of the positive and negative electrolytes.

[0094] Any additions, deletions, modifications, or improvements to the present embodiment that can be easily made by a person skilled in the art are within the scope of the present invention, which is defined by the appended claims. [Explanation of symbols]

[0095] 10: RF battery, 11: cell cartridge, 12: cell cartridge module, 13: backplane, 15: rack frame, 33, 34: electrolyte coupler, 40: system controller, 41: inverter, 42: charger, 44: leakage prevention coupler, 62: core unit, 100: RF battery, 101: cell stack, 104: each battery cell, 121: both electrode plates, 122: separator, 123: one electrode plate, 124: insulating bush, 125: fastening screw, 126: O-ring, 127: fastening screw, 431: conductive impermeable sheet, 432: resin frame sheet, 433: reaction electrode material, 441: socket, 442: plug, 1211: conductive plate, 1212: conductive sealing material, 1213: conductive adhesive, 1215: Resin frame plate, 1216: Electrolyte inlet / outlet groove, 1217: Electrolyte return inlet / return groove, 1231: Conductive plate, 1232: Conductive sealing material, 1233: Conductive adhesive, 1234: Reaction electrode material, 1235: Resin frame plate, 1236: O-ring groove

Claims

1. N cell cartridges (N is an integer equal to or greater than 1); a backplane having N or more mounting spaces, the cell cartridges being physically detachably mounted in the mounting spaces in a juxtaposed state with gaps provided between the cell cartridges; The cell cartridge is a flow battery having a plurality of stacked cells.

2. The flow battery according to claim 1, further comprising: The backplane includes a positive electrode liquid forward channel and a positive electrode liquid return channel that are connected to each of the cell cartridges, and couplers are provided at each connection point; A negative electrode liquid forward channel, a negative electrode liquid return channel, and couplers provided at each connection point, A flow battery in which the flow of positive and negative electrolytes to the cell cartridge attached to the backplane is ensured.

3. The flow battery according to claim 1, further comprising: Equipped with a rack frame, A plurality of stages of the backplanes are respectively attached to the rack frame, a positive and negative electrolyte forward connecting pipe and a positive and negative electrolyte return connecting pipe attached to the rack frame, and a positive and negative electrolyte forward channel and a positive and negative electrolyte return channel attached to each of the backplanes are respectively connected via couplers, thereby ensuring the flow of positive and negative electrolytes to each of the backplanes.

4. The flow battery according to claim 2 or 3, A flow battery, wherein the coupler is a coupler with an electrolyte leakage prevention function, and the backplane or the cell cartridge can be replaced without electrolyte leakage.

5. The flow battery according to claim 1 or 2, The cell is formed by stacking at least both electrode plates and / or one electrode plate and one separator as components, A flow battery, wherein some or all of the cell cartridge components are fixed to each other.

6. The flow battery according to claim 1 or 2, further comprising: A flow battery comprising a heat exchange part that exchanges heat by blowing air into the gaps between the cell cartridges.

7. The flow battery according to claim 1 or 2, further comprising: The backplane is provided with a diode functional component connected in parallel to each of the cell cartridges so that the anode is connected to the negative electrode of the cartridge and the cathode is connected to the positive electrode of the cartridge, thereby preventing an excessive reverse voltage from being applied to the backplane when a faulty cell cartridge is removed during operation.

8. The flow battery according to claim 1 or 2, further comprising: A flow battery, wherein the backplane is equipped with a sensor capable of measuring at least one of the voltage of each cell constituting the cell cartridge, and the flow rate, temperature, pressure, or oxidation-reduction potential of the positive and negative electrolytes.

9. The flow battery according to claim 2, further comprising: a positive electrode liquid outflow channel and a negative electrode liquid outflow channel of the backplane, each incorporating an electrolyte flow control valve.

10. The flow battery according to claim 1 or 2, further comprising: The battery includes an RF core unit, a plurality of positive electrode liquid tanks, and a plurality of negative electrode liquid tanks; The backplane is attached to the RF backbone unit in a plurality of stages, and the forward channel and the return channel are attached to the RF backbone unit; A flow battery in which one or more pairs of couplers with a leakage prevention function are attached to a pair of a positive electrode liquid forward channel and a positive electrode liquid return channel, and one or more pairs of couplers with a leakage prevention function are attached to a pair of a negative electrode liquid forward channel and a negative electrode liquid return channel, thereby enabling any number of electrolyte tanks and piping to be connected or disconnected via the couplers, thereby enabling the increase / decrease and replacement of the electrolyte to be charged / discharged.

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