178results about "Electrolyte stream management" patented technology

The invention relates to a liquid flow battery electrolyte storage device, and relates to the technical field of liquid flow battery electrolytes.The liquid flow battery electrolyte storage device comprises a tank shell and a heat exchange pipe, a spiral storage pipe barrel arranged in the vertical direction is arranged in the tank shell, electrolyte is arranged in the storage pipe barrel, the storage pipe barrel is connected with a liquid pump, the heat exchange pipe is spiral, and the heat exchange pipe is connected with the liquid pump. The storage pipe barrel is arranged vertically in a spiral mode and arranged outside the storage pipe barrel in a sleeving mode, heat exchange liquid is arranged in the heat exchange pipe, the heat exchange pipe is connected with a liquid supply circulating device, the flowing direction of the electrolyte is opposite to that of the heat exchange liquid, the storage pipe barrel is vertically arranged in a spiral mode, the electrolyte in the storage pipe barrel can form ordered layering in the storage pipe barrel, and therefore the heat exchange effect is improved. According to the utility model, the generation of a flowing dead zone is avoided, the occurrence of a side reaction, namely a hydrogen evolution reaction, caused by the mixing of two different ions is also reduced, the heat exchange area is increased, countercurrent flow heat exchange is realized, and the heat exchange efficiency of the device is further ensured.

A redox flow battery (1) comprising a cell arrangement (2), a control device (5), and two electrolyte circuits, wherein each electrolyte circuit comprises a tank (3) for storing electrolyte fluid, a piping system, and a pump (4) for circulating electrolyte fluid in the electrolyte circuit, and wherein the piping system comprises a supply line (6.1) from the tank (3) to the cell arrangement (2) and a return line (6.2) from the cell arrangement (2) to the tank (3), and wherein the pump (4) is arranged in the supply line, characterized in that each electrolyte circuit comprises an additional piping line (7) and a shut-off valve (8), wherein the shut-off valve (8) is arranged in the additional piping line (7), and wherein the additional piping line (7) branches off at a first end from the supply line (6.1) in the direction of flow of the electrolyte fluid downstream of the pump (4) and at a second end into the return line (6.1).2) terminates, and wherein the control device (5) is designed to control the closing states of the shut-off valves (8) in order to improve the mixing of the electrolyte fluid stored in the tanks (3) in predetermined operating conditions.

The utility model discloses an integrated electrode and a flow battery, the integrated electrode comprises a flow guide substrate and a reaction active electrode material wrapping the outer surface of the flow guide substrate, the reaction active electrode material is a flexible structure, the flow guide substrate comprises concave areas and convex areas which are alternately arranged, and the concave areas and the convex areas are arranged on the outer surface of the flow guide substrate. The inner side of the concave area and the back side of the convex area form an electrolyte flow channel, the electrolyte flow channel is provided with an electrolyte inlet and an electrolyte outlet which are exposed to the outer side of the reactive active electrode material, and the flow channel wall of the electrolyte flow channel is provided with a flow guide hole for guiding the electrolyte towards the reactive active electrode material; and the reaction active electrode material and the diversion substrate are relatively fixed to form an integrated structure of electrolyte circulation and electrochemical reaction. According to the scheme, efficient flowing of the electrolyte is guaranteed, a stable reaction interface is provided, concentration polarization is reduced, the battery efficiency is improved, meanwhile, the flow guide substrate is convenient to grab by a mechanical clamping jaw, and full-automatic stack assembly is supported.

Liquid membrane cell assemblies are disclosed. In some embodiments, the liquid membrane cell assembly includes an elongate base having opposed first and second end portions and a central portion disposed therebetween. The first and second end portions each includes an elongate body, an electrolyte channel within the body, an electrolyte port fluidly connected to the electrolyte channel, a fuel channel within the body, and a fuel port fluidly connected to the fuel channel. The central portion includes spaced and opposed first and second members that connect the bases of the first and second portions and that horizontally define an open area therebetween. The liquid membrane cell assembly additionally includes an anode adjacent the first and second members, and a cathode adjacent the first and second members such that the base is disposed between the anode and the cathode. The anode and cathode vertically define the open area therebetween.

The utility model discloses a vanadium-lithium combined energy storage power station system which comprises a frame body, a vanadium liquid flow unit, a lithium battery unit and a control unit, the vanadium liquid flow unit is arranged on the bottom layer of the frame body and comprises a negative electrolyte storage tank and a positive electrolyte storage tank, an electric pile and a circulating pipeline system are connected between the negative electrolyte storage tank and the positive electrolyte storage tank, and an electrolyte cooling system is arranged on the outer side of the electric pile; the lithium battery unit is arranged on the middle layer of the frame body and comprises a plurality of connected lithium battery modules, and air ducts are arranged among the plurality of lithium battery modules; the control unit is arranged on the top layer of the frame body and comprises a plurality of collecting modules, and the collecting modules are connected with the electrolyte cooling system and the air channel. According to the utility model, the rack body is arranged in a layered manner, and all units are integrated on the rack body, so that the purposes of compact structure and function integration are achieved. And the electrolyte cooling system and the air duct of the lithium battery module are connected with the acquisition module of the control unit, so that synergism of thermal management is realized.

The invention discloses a self-adaptive ballast adjustment method for a new energy ship based on a vanadium redox flow battery. The method comprises the following steps: establishing a collaborative arrangement structure of a vanadium redox flow battery and a ballast water dual system; based on the parameters of the collaborative arrangement structure, a linearization model capable of defining the relation between moment balance and the ship heeling angle and the ship heeling angle is constructed; constructing a target function for adaptive ballast adjustment of the new energy ship based on the linearization model; establishing a ballast adjustment constraint condition for the target function; based on the constructed heuristic solving strategy, the objective function is solved according to the ballast adjustment constraint condition to obtain an optimal solution, and the optimal solution is the optimal adjustment scheme of the electrolyte tank and the ballast water tank in the collaborative arrangement structure; based on the optimal solution, self-adaptive ballast adjustment of the new energy ship based on the vanadium redox flow battery is achieved. The problems that a traditional ballast system is slow in response, low in precision, uncontrollable in energy and the like, and rapid adjustment and high-precision control cannot be achieved are solved.

The invention provides a vanadium redox flow battery and a control method and device thereof. The redox flow battery comprises a power unit and an electrolyte storage tank, the electrolyte storage tank comprises a positive electrode electrolyte storage tank and a negative electrode electrolyte storage tank; a liquid level sensor is arranged on the electrolyte storage tank; the vanadium redox flow battery energy storage system further comprises a capacity recovery assembly; the capacity recovery assembly is communicated with a liquid outlet of the positive electrode electrolyte storage tank through a first liquid phase branch, is communicated with a liquid inlet of the positive electrode electrolyte storage tank through a second liquid phase branch, and is communicated with a liquid inlet of the negative electrode electrolyte storage tank through a third liquid phase branch; wherein the valence state of vanadium ions in the first electrolyte is higher than that of vanadium ions in the second electrolyte; the capacity recovery assembly is further communicated with a liquid outlet and a liquid inlet of the positive electrode electrolyte storage tank through a liquid phase circulation loop. According to the vanadium redox flow battery, part of the positive electrolyte is replaced through the capacity recovery assembly, so that the comprehensive valence state of the positive electrolyte and the negative electrolyte is maintained at 3.5 valence, and the battery capacity is recovered.

The utility model provides an electrolyte rebalancing system of an aqueous organic flow battery, which comprises the aqueous organic flow battery and an electrolyte rebalancing device, and the electrolyte rebalancing device comprises a negative electrode electrolyte rebalancing device and / or a positive electrode electrolyte rebalancing device. The electrolyte rebalancing system of the aqueous organic flow battery is simple, reasonable and compact in structure, extra electrochemical devices and extra chemical reagents are not introduced, and unbalanced electrolyte is rebalanced by designing a reserved interface and a bypass on an original battery system and introducing air into the electrolyte storage tank, so that the service life of the battery system is prolonged, and the service life of the battery system is prolonged. The problem of capacity imbalance after long-term operation of the water-based organic flow battery is solved, the service life of the water-based organic flow battery is prolonged, and the water-based organic flow battery has good application prospect and large-scale popularization potential in the field of electrolyte rebalance after long-term operation of the water-based organic flow battery.

This invention relates to the field of flow battery technology and discloses a method and system for regulating self-excited oscillation in flow batteries. By integrating a flow oscillation generator into the electrolyte circulation loop of the flow battery, the periodic vortex ring oscillation and acoustic-fluid positive feedback phenomenon generated by the flow within the resonant cavity of this device are utilized to achieve pulsating regulation of electrolyte flow rate and pressure. This fundamentally improves the convective mass transfer efficiency at the electrode / electrolyte / diaphragm interface within the flow battery stack, thereby alleviating concentration polarization at the battery reaction interface caused by factors such as uneven flow rate, thickened diffusion boundary layer, and restricted ion migration. Furthermore, this device eliminates the need for long-term, additional electrical drive and complex control components, exhibiting a simple structure and stable operation.

A redox flow battery includes a cell arrangement and a measuring apparatus for determining the charging state. The measuring apparatus comprises includes a hydraulic connecting line which connects the first tank to the second tank so that there is a permanent electrical connection between the electrolyte liquids in the two tanks. The measuring apparatus includes at least two electrodes. A first electrode is arranged directly in the positive electrolyte circuit. A second electrode is arranged directly in the negative electrolyte circuit. The redox flow battery includes a control apparatus which is designed such that it can detect a voltage difference between two electrodes.

The invention relates to the field of flow battery energy storage, in particular to a flow battery energy storage system and a control method.The flow battery energy storage system comprises an energy storage unit and a control management unit, and the control method of the energy storage system comprises the following steps that S1, the system is initialized and calibrated; s2, collecting and preprocessing multi-field coupling data; s3, trend prediction and target calculation; s4, hierarchical prediction cooperative regulation and control; s5, heat management and activity collaborative optimization; s6, full life cycle health monitoring and protection; and S7, carrying out model iteration and strategy optimization. According to the method, the electrolyte activity prediction model is constructed, the prediction regulation and control layer executes advance parameter adjustment, the problem of parameter matching lag caused by postmortem response in the traditional technology is thoroughly solved, and the system always adapts to the operation requirement in advance.

The invention relates to the technical field of flow batteries, and particularly discloses a catalytic system and a catalytic method of a flow battery. The catalytic system comprises an electric pile unit used for realizing conversion between electric energy and chemical energy; the electrolyte storage unit is used for storing electrolyte and comprises a positive electrode electrolyte storage unit and a negative electrode electrolyte storage unit, and functional particles are arranged in the positive electrode electrolyte storage unit and / or the negative electrode electrolyte storage unit; the ultrasonic unit is used for promoting the functional particles to be in contact with the positive electrode electrolyte and / or the negative electrode electrolyte for electrification to generate an electrostatic field; and the circulating unit is used for realizing circulation of the electrolyte between the electrolyte storage unit and the electric pile unit. According to the flow battery catalytic system, the electron transfer process can be optimized, and the problems of slow reaction kinetics and noble metal dependence of the flow battery are solved.

An electrochemical reactor, which may be a half-cell of a rechargeable battery, comprises a liquid electrolyte which is pumped through the half-cell and has an electrochemical system in which a solid is deposited at an electrode while electric current is flowing. The liquid comprises a high molecular weight polymer or a viscoelastic surfactant enabling elastic turbulence to occur and the half-cell is configured to compel through flow to make changes in direction, so that elastic turbulence occurs, enhancing mass transport through the liquid and reducing overpotential at the electrode, which enhances uniformity of deposited solid and inhibits parasitic reactions.

The utility model relates to a multifunctional metal air fuel cell device which is characterized by comprising an outer shell, an air electrode and a magnesium alloy plate group, when the multifunctional metal air fuel cell provided by the utility model is used as a power supply of the emergency LED lamp, the cell can be quickly activated in emergency only by adding simple electrolyte, such as saline water, so that the requirement of emergency rescue can be met, and the multifunctional metal air fuel cell can also be used as a camping lamp for a long time; importantly, in the whole life cycle of the magnesium air fuel cell, electrolyte can be supplemented for multiple times, the service life of the product is greatly prolonged, and the requirement for long-time illumination under the condition that charging cannot be carried out can be met.

The invention relates to the technical field of all-vanadium redox flow batteries, in particular to an all-vanadium redox flow battery thermal management system utilizing a phase change material, which comprises an electrolyte storage tank, an electrolyte cavity and a phase change cavity are arranged in the electrolyte storage tank, the phase change cavity is filled with the phase change material, and the phase change cavity comprises an inner cavity and an outer cavity which are communicated with each other. The temperature of the phase change material is basically constant in the phase change process, and the problem that temperature fluctuation is large in traditional sensible heat temperature control is effectively solved.

The invention relates to an all-vanadium redox flow battery energy storage automatic operation and maintenance system and method, and the system comprises a plurality of all-vanadium redox flow battery energy storage modules which are used for achieving the storage and release of electric energy through the valence change of vanadium ions; the all-vanadium redox flow battery energy storage module is connected with the reducing agent module through the reducing agent automatic control system, and the reducing agent automatic control system is used for feeding a reducing agent preset in advance in the reducing agent module into the all-vanadium redox flow battery energy storage module in a timed and quantitative manner; the vanadium redox flow battery energy storage module is also connected with a temperature monitoring device and is used for monitoring the temperature of the all-vanadium redox flow battery energy storage module on line; the all-vanadium redox flow battery energy storage module is connected with the heat exchange circulation module, and the heat exchange circulation module is used for cooling or increasing the temperature of the all-vanadium redox flow battery energy storage module according to a temperature signal sent by the temperature monitoring device. The energy storage quality and stability of the flow battery system can be improved.

A flow battery cycle recovery system and method. The flow battery cycle recovery system comprises: a positive electrode liquid storage tank containing a positive electrode electrolyte, wherein the positive electrode electrolyte contains reducing ions and active ions, and the reducing ions can react with the active ions to reduce the valence state of the active ions and generate a first oxidizing gas; a catalytic reaction apparatus containing a catalyst, wherein the catalytic reaction apparatus can receive the first oxidizing gas to oxidize and immobilize the catalyst; and a negative electrode liquid storage tank containing a negative electrode electrolyte, wherein the negative electrode electrolyte undergoes a side reaction to generate a first reducing gas. The catalytic reaction apparatus can receive the first reducing gas, the first reducing gas is used for reducing the oxidized catalyst, and the resulting acid gas can be returned to the negative electrode liquid storage tank.

This invention discloses a multifunctional electrochemical system coupling a flow battery and indirect organic electrosynthesis. The multifunctional electrochemical system includes a flow battery module and an indirect electrosynthesis module. The flow battery module includes an anolyte storage tank, a cathode storage tank, a circulating pump, a battery stack, and a power source or load. This invention couples a flow battery and indirect organic electrosynthesis into a unified electrochemical system, achieving a dual breakthrough in function and technology. On the one hand, it endows the flow battery with the dual functions of "energy storage and electrosynthesis." During periods of low electricity demand, the flow battery stores excess electrical energy; when needed, it can be used to drive the indirect organic electrosynthesis reaction, effectively improving equipment utilization and reducing unit costs. On the other hand, by utilizing the stable power supply characteristics of the flow battery through the coupling mechanism, it solves the problem of unstable renewable energy supply, providing continuous power for indirect organic electrosynthesis, fundamentally addressing the pain points of existing flow batteries and direct electrosynthesis technologies.

The invention discloses a thermal regeneration flow battery based on a cold and hot battery function asymmetric structure design and a use method, and belongs to the field of low-grade heat energy recovery and electrochemical energy conversion, and the thermal regeneration flow battery comprises a cold battery running at a low temperature, a thermal battery running at a high temperature, an electrolyte circulating system and an external circuit. The core of the invention lies in that aiming at the inherent difference of a cold battery and a thermal battery in thermodynamic driving force, reaction kinetics path and interface reaction mechanism, corresponding key functional units in the cold battery and the thermal battery, such as an electrode material and interface structure, an electrode microstructure, diaphragm characteristics, electrolyte local environment or operation conditions, and the like, are subjected to thermal power conversion. Differentiated structure configuration or parameter setting is carried out, so that collaborative optimization of cold and hot end reactions is realized. According to the method, the system polarization is remarkably reduced, the output power density and the thermoelectric conversion efficiency are improved, the long-term operation stability is enhanced, and a new technical approach is provided for efficiently recycling low-grade heat energy.

A protective layer for an electrolyte in a flow battery and an electrolyte tank having a protective layer. The protective layer includes a light oil that includes hydrophobic hydrocarbons. The light oil having a density lower than a density of the electrolyte, the hydrophobic hydrocarbons being non-reactive to the electrolyte. The protective layer may be a liquid layer or may include a substrate impregnated with the light oil. An inert gas may also be utilized in the electrolyte tank.

A flow battery system with a cathode cell including a first electrode, an anode cell includes a second electrode, and a membrane between the two cells. A first electrolyte tank includes a catholyte. A second electrolyte tank includes an anolyte. The system includes two rebalancing cells. A first rebalancing cell is in fluid communication between the cathode cell and the first electrolyte tank and is configured to reduce active species from the catholyte. The second rebalancing cell is in fluid communication with the first electrolyte tank and the second electrolyte tank such that the first electrolyte tank and the second electrolyte tank are in direct fluid communication. The second rebalancing cell is configured to reduce active species from the catholyte and the reduced catholyte may be combined directly with the anolyte. The second rebalancing cell may be a chemical reactor, a catalytic reactor, or an electrochemical reactor.

The application discloses a hierarchical tank design for improving the system efficiency and capacity utilization of a flow battery system and belongs to the technical field of flow batteries; the application comprises a plurality of electrolyte tanks arranged on the positive electrode side and a plurality of electrolyte tanks arranged on the negative electrode side, the plurality of tanks on the two sides are connected together in a series mode and form a circulating loop with the flow battery, the hierarchical tank design improves the consistency of the state of charge of the electrolyte in the tank, effectively improves the average current of the constant voltage section of the battery, reduces the pump consumption under the high state of charge, and thus improves the system efficiency of the flow battery; meanwhile, the utilization rate of the electrolyte is also greatly improved.

A method for producing a nitrogen-enriched current from an electrochemical system. The method includes operating the electrochemical system in a running state, operating the electrochemical system in a shut-off state to produce a nitrogen-enriched current on a cathode side of the electrochemical system, and venting the nitrogen-enriched current from the cathode side of the electrochemical system through a vent valve to remove the nitrogen-enriched current from the electrochemical system. The generated nitrogen gas can be used for purging, covering, cooling, and / or diagnosing the state of health (SoH) of an electrochemical system, such as a PEMFC system.

The invention belongs to the technical field of flow batteries, and relates to an electrolyte containing a polyanionic electrolyte additive and a flow battery. Comprising a viologen compound, a supporting electrolyte, a solvent and a polyanionic electrolyte additive, the polyanionic electrolyte additive accounts for 0.1%-20% of the electrolyte in percentage by mass; molecules of the polyanionic electrolyte additive are rich in various functional groups with negative charges, and the polyanionic electrolyte additive is used for interfering the pi-pi accumulation behavior of viologen molecules; the polyanionic electrolyte additive is a polymer containing a repetitive unit, and is sodium polystyrenesulfonate, sodium polyacrylate, poly (2-acrylamido-2-methyl sodium propanesulfonate) or sodium alginate. By introducing a polymer carrying high-density negative charges in the structure or aggregated inorganic anions, multiple regulation and control effects on viologen molecules in a water-phase environment are realized, aggregation behaviors of reduced molecules of the viologen molecules are remarkably inhibited, and chemical and electrochemical stability of the electrolyte is improved.

The utility model discloses a high-efficiency flow battery system based on heat recovery. The high-efficiency flow battery system comprises a flow battery system, a heat pump and a heat storage water tank, the heat pump comprises two heat pump cycles which are composed of a condenser, a throttling valve, an evaporator, a secondary evaporation heat exchanger and a compressor and can be switched through a three-way valve. The heat storage water tank is connected with the heat exchange medium side of the condenser to form a heat storage loop; a first coil pipe is arranged in an electrolyte storage tank of the flow battery system, and the first coil pipe is connected with a heat exchange medium side of a secondary evaporation heat exchanger to form a heat recovery loop; a second coil pipe is arranged in the heat storage water tank and is connected with the first coil pipe to form an electrolyte preheating loop; and the heat recovery loop and the electrolyte preheating loop can be switched through corresponding three-way valves. According to the system, the problems of electrolyte waste heat recycling and electrolyte preheating during cold start are solved through cooperation of one set of system, the heat utilization rate of the system is improved, and meanwhile the design and operation difficulty is lowered.

An electrolytic cell comprising an electrolytic reaction chamber, the electrolytic reaction chamber comprising At least one electrode assembly comprising at least one cathode, at least one anode and at least one ion-permeable layer arranged between the at least one cathode and the at least one anode; and a channel system comprising at least one electrolyte fluid inlet, and at least one electrolyte fluid outlet, the channel system comprising at least one channel fluidly connecting the at least one electrolyte fluid inlet, the electrode assembly and the at least one electrolyte fluid outlet; wherein the electrolytic reaction chamber is rotatably mounted such that the electrolytic reaction chamber is rotatable about a rotation axis and wherein at least the at least one ion-permeable layer is configured to at least partially extend in a radial direction with respect to the rotation axis.

Disclosed is an electro-energy or electro-synthetic cell, comprising a cathode, an anode and an electrode separator positioned between the cathode and the anode. A liquid electrolyte inlet supplies a liquid electrolyte to the cell, and a liquid electrolyte outlet removes the liquid electrolyte from the cell. The liquid electrolyte outlet comprises an overflow weir over or through which excess liquid electrolyte flows out of the cell. In another form, one or more drippers are included as part of the liquid electrolyte inlet and / or the liquid electrolyte outlet and drip chambers are positioned below the drippers. In another form, one or more porous capillary structures are located in liquid pathways in the cell, for example in a liquid pathway provided by an overflow weir or adjacent a dripper. In another form, one or more restrictors are utilised that create a pressure drop in the liquid electrolyte passing through the restrictor.

The application discloses a kind of based on wide temperature environment self-organizing adaptation's all-vanadium redox flow energy storage system, including all-vanadium redox flow battery module, multi-physical field perception network and all-temperature range self-organizing adaptation controller.Multiple physical field perception network obtains the data such as each valence state concentration of electrolyte, total vanadium concentration and the temperature field inside the stack by multi-source sensor in real time, and all-temperature range self-organizing adaptation controller integrates electrolyte state self-adaptive module and stack thermal field self-balancing module, electrolyte state self-adaptive module is based on physical information neural network Construction prediction model, according to the prediction result, actively adjust electrolyte temperature and circulating pump flow;Stack thermal field self-balancing module is accurately adjusted electrolyte flow distribution by the electrically controlled valve independently arranged in each branch flow channel, based on PID control algorithm, and realizes two-stage thermal management in combination with external liquid cooling system.The application can be stably operated under the wide temperature environment of-30~50 ℃, effectively eliminate local hot spots inside the stack, prolong the service life of system.

The invention relates to the technical field of intelligent operation and maintenance of energy storage power stations, and discloses an intelligent operation and maintenance scheduling optimization method of an energy storage power station based on cloud-edge collaboration, which comprises the following steps: applying flow velocity pulse excitation to a circulating pump at a station end and collecting fluid response of each branch, constructing electrolyte retention time distribution and extracting statistics reflecting long tail retention; meanwhile, the bypass shunting intensity is calculated in combination with potential gradient data of the public liquid supply manifold, and then a coupling index reflecting the effective capacity attenuation degree is formed; and the edge monitoring end calculates a module capacity loss rate according to the module capacity loss rate, compares the module capacity loss rate with an allowable degradation threshold issued by the cloud end, generates a normal or abnormal operation and maintenance scheduling result, outputs a branch risk sequence and an operation and maintenance work order under an abnormal condition, and realizes online identification and refined operation and maintenance management of the hidden efficiency degradation problem of the energy storage power station.

In order to detect leakages of an electrolyte in a redox flow battery at an early stage and also without a corresponding leakage sensor system and in order to interrupt a siphon effect which is produced, it is proposed that a pipe assembly (50) is arranged in the electrolyte tank (13a, 13b), which pipe assembly comprises at least two pipes (51, 52, 61, 62) of different lengths, wherein each of the at least two pipes (51, 52, 61, 62) has a first axial end (51-1, 52-1, 61-1, 62-1) and a second axial end (51-2, 52-2, 61-2, 62-2), which are connected to one another in each case by a flow volume (53, 54, 63, 64), wherein the first axial ends (51-1, 52-1, 61-1, 62-1) are open and end in the electrolyte tank (13a, 13b) at different depths (T1, T2, T3, T4), wherein the second ends (51-2, 52-2, 61-2, 62-2), opposite the first axial ends (51-1, 52-1, 61-1, 62-1), of the at least two pipes (51, 52, 61, 62) open into a mixing volume (56) in a connection pipe (55), wherein the flow volumes (53, 54, 63, 64) of the at least two pipes (51, 52, 61, 62) are connected to one another via the mixing volume (56) and wherein the mixing volume (56) is located above the fill level (LVa, LVb) of the electrolyte (15a, 15b) when the electrolyte tank (13a, 13b) is used.