DE102017108439A1 - Electrochemical device, functional element and process for its preparation - Google Patents

Abstract

The invention is based on an electrochemical device, in particular an electrolysis device, in particular a polymer electrolyte membrane electrolysis device, having at least one cell unit (12) which comprises at least one electrochemical cell (14).
It is proposed that the electrochemical cell (14) has at least one contact element (18) which is different from a connection element (22, 24) for a power supply (26).

Description

State of the art

The invention relates to an electrochemical device according to the preamble of claim 1, a functional element according to the preamble of claim 15 and a method for producing a functional element according to claim 16.

Electrolysers are known from the prior art, which have a cell stack, often referred to as a "stack", having a plurality of series-connected electrolysis cells. An operating voltage is applied to the entire cell stack, often monitoring its timing and / or a time history of a total current, in order to identify any disturbances and / or a need for a change of operating parameters.

The object of the invention is in particular to achieve advantageous properties in terms of a construction. Furthermore, an object of the invention is in particular to achieve a simple and / or reliable monitoring of parts of a cell stack. In addition, an object of the invention is in particular to achieve advantageous properties in terms of a simple and / or cost-effective production. The object is achieved by the features of claim 1, while advantageous embodiments and modifications of the invention can be taken from the dependent claims.

Advantages of the invention

The invention is based on an electrochemical device, in particular an electrolysis device, in particular a polymer electrolyte membrane electrolysis device, having at least one cell unit comprising at least one electrochemical cell.

It is proposed that the electrochemical cell has at least one contact element that is different from a connection element for a power supply.

The inventive design, an advantageous construction can be achieved. Furthermore, an electrochemical device can be provided whose operation can be easily and / or reliably monitored. In addition, a low-cost and / or easy-to-manufacture electrochemical device can be provided. Furthermore, advantageous properties with regard to a simple and / or cost-effective production of components of an electrochemical device can be achieved. Advantageously, operating parameters of parts of an electrochemical device, in particular of individual electrochemical cells, can be reliably measured. Furthermore, a large number of contact elements can be provided in a small space, whereby in particular single cell measurements can be made possible on a large number of adjacent cells. In addition, even very thin single cells can be reliably contacted. In addition, a high reliability and / or a high load capacity of electrical contact elements can be achieved.

An "electrochemical device" should in particular be understood to mean at least one, preferably functional, part of a device and / or a machine, in particular an electrolyzer, which is provided for carrying out at least one at least partially electrochemical working step. In particular, the electrochemical device may also comprise the entire device and / or the entire machine. Preferably, the electrochemical device is intended to convert electrical energy into chemical binding energy and / or chemical binding energy into electrical energy. In particular, at least in at least one normal operating state, at least one chemical reaction takes place, which is linked to an electric current, in particular a redox reaction. For example, the electrochemical device may include a fuel cell device, a battery device, a meter device, a generator device, an analyzer, an electrode position device, an anodization device, a plating device, a redox reactor device, or the like. Preferably, the electrochemical device is designed as an electrolysis device, particularly preferably as a hydrogen electrolysis device, which is provided in particular for the electrochemical cleavage of water into hydrogen and oxygen. The electrochemical device can be provided to provide at least one gas, in particular hydrogen, with an overpressure to an environment, in particular with a pressure of at least 1 bar, whereby pressures of at least 5 bar, at least 10 bar, at least 15 bar, at least 20 bar , at least 30 bar or even greater pressures are conceivable. In particular, the electrochemical device can be provided for connection to a gas container, in particular a hydrogen tank, it being conceivable for an operating pressure of the electrochemical device to be adaptable and / or adapted to a filling level of the gas container. For example, it is conceivable that the electrochemical device generates the gas against a filling pressure of the gas container and this filled in particular without the use of a compressor or the like. Alternatively, it is also conceivable that the electrochemical device is at least substantially free of an overpressure is operated. Furthermore, it is conceivable that the electrochemical device is operable at a constant pressure and / or is operated in the normal operating state with a constant working pressure. In particular, in this case, a combination with a compressor is conceivable. In addition, the electrochemical device can be a high-pressure electrolysis device and, in particular, provided to produce and / or provide at least one gas, in particular hydrogen, at a pressure of at least 50 bar, preferably at least 70 bar and more preferably at least 100 bar or even more. By "provided" is intended to be understood in particular specially programmed, designed and / or equipped. The fact that an object is intended for a specific function should in particular mean that the object fulfills and / or executes this specific function in at least one application and / or operating state.

An "electrochemical cell" is to be understood in particular as a functional unit by means of which at least one electrochemical reaction can be carried out, in particular an electrochemical reaction of the type for the implementation of which the electrochemical device is provided. For example, the electrochemical cell may be a fuel cell, a battery cell, a measuring cell, a redox cell or the like. Advantageously, the electrochemical cell is an electrolytic cell. Particularly advantageously, the electrochemical cell is a cell stack-compatible electrolysis cell, in particular an electrolysis cell stack. Advantageously, the electrochemical cell comprises at least one anode, to which oxygen is preferably formed in the normal operating state. The electrochemical cell preferably comprises at least one cathode, to which hydrogen is preferably formed in the normal operating state. Advantageously, the electrochemical cell comprises at least one membrane, in particular an advantageously selectively proton-conducting membrane, preferably a polymer electrolyte membrane. Particularly preferably, the anode and the cathode are separated from one another at least by the membrane. In particular, the anode and / or the cathode is planar and / or layered and / or a layer and / or coating. Preferably, the membrane is formed at least partially, and more preferably at least a major portion of Nafion. Preferably, the electrochemical cell comprises at least one functional element, in particular a bipolar element, preferably a bipolar plate. In particular, a first side of the bipolar element forms an anode side of an electrochemical cell, and in particular a second side of the bipolar element forms a cathode side of an immediately adjacent other electrochemical cell. In particular, at least some, advantageously at least a large part and particularly advantageously all electrochemical cells of the cell unit are at least substantially identical in construction and / or of the same and / or of an analogous construction. By "at least substantially identical" objects, in this context, objects are to be understood in particular that are constructed in such a way that they can each perform a common function and differ in their construction apart from manufacturing tolerances at most by individual elements that are insignificant for the common function are, and advantageous objects that are identical except for manufacturing tolerances and / or in the context of production engineering possibilities, which should be understood by identical objects in particular also mutually symmetrical objects. At least 55%, advantageously at least 65%, preferably at least 75%, particularly preferably at least 85%, and particularly advantageously at least 95%, but in particular also completely, is to be understood by the term "at least a majority". At least 55%, advantageously at least 65%, preferably at least 75%, particularly preferably at least 85%, and particularly advantageously at least 95%, but in particular also 100%, are to be understood by the term "at least a large part". Preferably, the cell unit comprises a plurality, preferably a plurality, of, in particular at least substantially identically formed, electrochemical cells. Advantageously, the cell unit comprises at least one cell stack, in particular an electrolysis stack, which comprises a plurality, preferably a multiplicity, of stacked electrochemical cells. Preferably, the cell stack comprises at least the electrochemical cell. Advantageously, the electrochemical cells of the cell stack are at least substantially identical. The cell stack preferably has repeating units which comprise a plurality of different functional elements, advantageously different functional cell stack elements, for example, in particular in the stated order, at least one bipolar plate and / or at least one screen plate and / or perforated plate or the like and / or at least one gas diffusion layer, in particular an oxygen diffusion layer, advantageously a titanium felt and / or a membrane, advantageously a polymer electrolyte membrane, and / or a further gas diffusion layer, in particular a hydrogen diffusion layer, advantageously a carbon felt, and / or a compression buffer, in particular comprising a further screen plate and / or perforated plate, in particular a compression pad, advantageously an expanded metal. Advantageously, a bipolar plate and / or a perforated plate and / or a screen plate and / or an expanded metal and / or another metallic cell stack element is at least partially advantageous at least a majority of titanium and / or stainless steel and / or formed of at least one coated metal. In particular, one electrochemical cell each extends from one bipolar plate to a next bipolar plate. The cell stack may comprise any number of electrochemical cells, for example ten or twenty or thirty or fifty or one hundred or fifteen hundred or two hundred or more or fewer or any intervening number. Advantageously, the cell unit has exactly one cell stack. However, it is also conceivable for the cell unit to comprise a plurality of cell stacks, in particular at least substantially identical or differently designed, of which at least some may be connected electrically and / or hydraulically in series and / or in series.

The cell unit preferably has at least one first end plate and / or at least one second end plate. Particularly preferably, the electrochemical cells of the cell stack are arranged between the end plates, in particular densely stacked. Preferably, the first end plate and the second end plate are connected together.

Particularly preferably, the first end plate and the second end plate act on the cell stack from opposite sides and in particular in a direction perpendicular and / or at least substantially perpendicular to a stacking direction with a compressive force. Preferably, the stacking direction corresponds to a direction in which the cell stack is constructed of electrochemical cells. In particular, the stacking direction is perpendicular and / or at least substantially perpendicular to a main extension plane of the first electrochemical cell and / or perpendicular to a main extension plane of at least one, in particular plate-shaped, cell stack element. The cell stack is preferably such that main extension planes of the electrochemical cells of the cell stack are arranged parallel to one another and in particular perpendicular to the stacking direction. Preferably, in the normal operating state, a working voltage is applied between a foremost electrochemical cell, which bears in particular against the first end plate, and a rearmost electrochemical cell, which bears in particular against the second end plate. In particular, in the case where the electrochemical device is designed as an electrolysis device, in the normal operating state, in each case, an individual working voltage of at least 0.5 V, advantageously of at least 1 V, particularly advantageously of at least 1, lies on the electrochemical cells, in particular of the cell stack. 2 V and preferably of at least 1.5 V and / or of at most 10 V, advantageously of at most 5V, more preferably of at most 2.5 V and preferably of at most 2 V an. However, it is conceivable, in particular for other cases, for example for a fuel cell device, that in the normal operating state, an individual working voltage is applied to the electrochemical cells, in particular of the cell stack, which is less than 1 V or less than 0.5 V or even less smaller or for example also greater than 10 V or greater than 20 V or greater than 50 V or even greater. A person skilled in the art will select a suitable individual working voltage according to an application as desired. A "main extension plane" of an object should be understood to mean, in particular, a plane which is parallel to a largest side surface of a smallest imaginary cuboid which just completely surrounds the object, and in particular runs through the center of the cuboid. By "at least substantially perpendicular" is meant in particular an alignment of a direction relative to a reference direction, in particular in a reference plane, wherein the direction and the reference direction include an angle, in particular less than 8 °, preferably less than 5 ° and particularly advantageously deviates less than 2 ° from a right angle.

In particular, the cell unit has at least one first connection element and at least one second connection element for connection to a power supply. Advantageously, in the normal operating state, an overall operating voltage is applied between the first connection element and the second connection element. Preferably, the connection elements are arranged on the, in particular opposite, end plates of the cell stack. Particularly advantageously, in the normal operating state, a total operating current, in particular a direct current, flows from the first connection element to the second connection element or vice versa.

In particular, the contact element is electrically connected to the electrochemical cell, in particular to at least one functional and / or electrochemically active component of the electrochemical cell. For example, the contact element may be welded to the functional component and / or soldered. It is also conceivable that the contact element is plugged into the functional component and / or otherwise positively and / or positively connected thereto. Advantageously, the contact element is at least partially connected in one piece with the functional component. In the normal operating state, the contact element is preferably at a potential of an anode or at a potential of a cathode of the electrochemical cell. Advantageously, the contact element is at least partially, particularly advantageously at least a large part and / or formed entirely of metal, for example titanium and / or or steel and / or copper and / or other suitable metal. Advantageously, the contact element is assigned to two directly adjacent electrochemical cells. Particularly advantageously, in each case two adjacent electrochemical cells are assigned a common contact element. Preferably, two contact elements are assigned to the electrochemical cell, one of which is at an anode potential and one at a cathode potential of the electrochemical cell. This is particularly preferably the case for a plurality and / or for all cells of the cell unit and / or the cell stack. Particularly in the case of directly adjacent electrochemical cells, it is conceivable that the contact element is for example at an anode potential of one electrochemical cell and at a cathode potential of the immediately adjacent electrochemical cell or vice versa, in particular in the case of a series connection of electrochemical cells such as in the cell stack. In particular, the contact element is accessible from an exterior of the cell unit, in particular from an exterior of the cell stack, preferably from an exterior of the electrochemical device. Preferably, the contact element is arranged outside an active interior of the cell unit.

In an advantageous embodiment of the invention, it is proposed that the electrochemical cell comprises at least one functional element, in particular at least one functional cell stack element, which has the contact element. Preferably, the functional element is plate-shaped and / or plate-like and / or sheet-shaped and / or sheet-like. For example, the functional element may comprise and / or be designed as a bipolar plate and / or a perforated plate and / or a screen plate and / or a gas distribution element, in particular a gas distribution plate element and / or a compression buffer, in particular a compression pad or the like. In particular, the functional element is at least partially, advantageously at least a large part and particularly advantageously completely made of metal and / or has a metal-like or at least metal-like conductivity, in particular in a lateral direction. In this way, advantageously, a single electrochemical cell, in particular a cell stack, can be contacted easily and / or reliably.

In a particularly advantageous embodiment of the invention it is proposed that the contact element and at least one functional component of the functional element are at least partially connected in one piece. Preferably, the contact element and the functional component are integrally formed. In particular, the functional component is arranged at least partially within an active volume of the electrochemical cell, within which at least one reaction step of the chemical reaction takes place, at least one partial step of a hydrogen electrolysis, at least in the normal operating state. By the fact that a first object and a second object are "at least partially integral" with each other, should be understood in particular that at least one element and / or part of the first object is integrally connected to at least one element and / or part of the second object. By "in one piece" is meant, in particular, at least materially bonded, for example by a welding process, an adhesion process, an injection process and / or another process which appears expedient to a person skilled in the art, and / or advantageously shaped in one piece, for example by manufacture a casting and / or by a production in a one- or multi-component injection molding process and advantageously from a single blank. As a result, advantageously a high reliability of a contact can be achieved.

In addition, it is proposed that the contact element is designed as a nose-like projection of a plate, in particular a sheet. Advantageously, the functional component on the plate, in particular the sheet. Particularly advantageously, the sheet is formed as a titanium sheet. In particular, the plate forms the contact element. In particular, the contact element and the plate, in particular the sheet, are produced from a common blank and / or produced. Particularly advantageously, the functional element is at least partially as a stamped part, in particular a stamped sheet metal part, and / or as a stamped and bent part, in particular a stamped sheet metal bent part formed. Preferably, the contact element is designed as a blade contact element. In particular, the contact element is flat and / or flat. Preferably, a main extension plane of the contact element is arranged at least substantially parallel to a main extension plane of the functional element. In particular, the contact element and the functional component have a common main extension plane. Advantageously, the main extension plane of the contact element is arranged at least substantially perpendicular to the stacking direction. As a result, advantageously low production costs can be achieved. In addition, this can be achieved by a simple and / or reliable electrical contactability.

Furthermore, it is proposed that the electrochemical cell has a thickness of at most 5 mm, advantageously of at most 3 mm, and particularly advantageously of at most 2 mm, in particular a thickness measured parallel to the stacking direction, whereby in particular an advantageous Compactness and / or a high power density, in particular a cell stack, for example in the case of a large number of stacked cells, can be achieved. Of course, even smaller or larger thicknesses are conceivable. Preferably, the electrochemical cells of the cell stack are at least substantially the same thickness.

Furthermore, it is proposed that the cell unit has at least one further electrochemical cell with at least one further contact element. Advantageously, the further electrochemical cell is at least substantially identical to the electrochemical cell. Particularly advantageously, the further contact element is at least substantially identical to the contact element. In particular, the further electrochemical cell of the electrochemical cell, in particular immediately adjacent. The electrochemical cell and the further electrochemical cell can, in particular independently of each other, be arranged at arbitrary positions of the cell unit, in particular of the cell stack. Preferably, a plurality and / or a plurality of electrochemical cells of the cell unit each have at least one, in particular exactly one, contact element. In particular, it is conceivable that each electrochemical cell of the cell unit has at least one contact element. Advantageously, the cells of the cell unit each have a functional element with at least one contact element for contacting the corresponding electrochemical cell, in particular its anode and / or cathode, wherein the functional elements are each preferably functional elements of the same type and / or of the same type, for example, in each case by a bipolar plate and / or in each case by a perforated plate and / or in each case by an expanded metal or the like. If directly adjacent electrochemical cells each have at least one contact element, a distance between the corresponding contact elements, in particular measured along the stacking direction, corresponds at least substantially to a thickness of the electrochemical cells. It is also conceivable that contact elements of electrochemical cells are arranged at different positions of their respective cell with respect to the stacking direction. In particular, preferably in the case of adjacently arranged electrochemical cells, corresponding contact elements may be arranged on opposite sides of their respective electrochemical cell in the stacking direction, whereby in particular a larger space for contacting the contact elements can be provided. For example, in this case it is conceivable that contact elements, in particular adjacent, electrochemical cells are arranged on functional elements of different types. For example, the contact element of the electrochemical cell may be arranged on its bipolar plate, while the further contact element of the further electrochemical cell is arranged on its perforated plate, wherein, of course, any functional elements are conceivable in this context. Preferably, in each case at least one contact element lies in each case at an anode potential or at a cathode potential in accordance with contactable electrochemical cells. Advantageously, individual cell parameters, for example individual voltages, can thus be queried simply and / or reliably.

A high space efficiency can be achieved in particular and / or space for attaching contacts can be provided in particular if the contact element and the further contact element are arranged offset to one another, in particular in a view in the stacking direction. Advantageously, the electrochemical cell and the further electrochemical cell are aligned in the stacking direction, wherein advantageously the contact element and the further contact element at different positions of the respective electrochemical cell, in particular at different positions of a respective outer edge of the respective electrochemical cell are arranged.

An electrochemical device with advantageous properties with regard to a possibility for contacting individual cells, in particular in the case of thin cells, can be provided in particular if at least a plurality of the electrochemical cells of the cell stack, in particular all electrochemical cells of the cell stack, each have at least one contact element, wherein at least some of the contact elements are arranged offset from one another. In particular, contact elements of directly adjacent electrochemical cells are each arranged offset from one another. Preferably, two immediately adjacent contact elements are assigned to an electrochemical cell. Each contact element is particularly preferably associated with two directly adjacent electrochemical cells, in particular an anode of one and a cathode of the other electrochemical cell.

In an advantageous embodiment of the invention it is proposed that at least some of the contact elements of the cell stack in a viewing along a stacking direction in multiple rows, for example, in two or three or four or five or six rows are arranged. Advantageously, the rows are at least substantially parallel to the stacking direction. The contact elements, in particular the rows, are preferably arranged on a common side of the cell unit, in particular of the cell stack. It is also conceivable that some contact elements and / or Rows on different, in particular arranged perpendicular to the stacking direction, sides of the cell unit, in particular of the cell stack are arranged. Advantageously, at least for a portion of the cell stack, a contact element of each ith of the electrochemical cell is disposed in an ith of the rows, where i denotes a natural number. Preferably, the contact elements in a view of the cell stack are arranged in a staircase perpendicular to the stacking direction. In particular, in this case, a distance between in a row immediately behind one another arranged contact elements is constant. But it is also conceivable that at least for a portion of the cell stack, the contact elements are arbitrarily different, especially random, associated with the rows. This can advantageously be increased in a simple and / or cost-effective manner a ready for contacting contact elements space.

In a further embodiment of the invention, it is proposed that the electrochemical device has at least one bridging element which is provided to produce in at least one operating state an electrical connection between the contact element and at least one other contact element, in particular the further contact element, by at least one, in particular to bridge one or more in particular adjacent arranged arranged electrochemical cells, part of the cell unit, in particular of the cell stack. In particular, at least one first contact region of the bridging element is provided for connection to the contact element. Preferably, at least one second contact region of the bridging element is provided for, in particular simultaneous, connection to the other contact element, wherein preferably the contact elements are connected. Advantageously, the bridging element is provided for attachment and / or removal. It is also conceivable that the bridging element is welded and / or soldered. Preferably, the bridging element is provided for a, in particular manual, attachment to the cell unit by a user. However, it is also conceivable that the bridging element has at least one, in particular at least partially automated, switch which enables, for example, at least temporary switching on and / or at least temporary shutdown of at least a part of the cell unit, in particular of the cell stack. In addition, it is conceivable that the bridging element is arranged at a distance from the cell unit and, for example, connected to the contact elements by means of suitable electrical lines. In particular, in this case, the bridging element may be formed as an electrical and / or electronic circuit. It is also conceivable that the bridging element is provided for a connection of more than two contact elements. In particular, the operating state may be an error operating state in which at least one electrochemical cell is not operable and / or operated properly and, in particular, is bypassed. The operating state may alternatively or additionally also be a measuring operating state and / or a maintenance operating state in which, in particular, maintenance work and / or measurements or the like can be performed on at least one bridged electrochemical cell. In addition, the operating state can also be the normal operating state. Preferably, the bridging element bridges between the contact element and the other contact element arranged electrochemical cells. In particular, the contact elements and / or the bridging element are dimensioned such that a normal operating current can flow through them without damage. Preferably, at least one bridging part of the bridging element is conductive. In particular, the bridging element may be formed as a metal clip and / or a cable with corresponding connection elements or the like. As a result, advantageously, a part of a cell unit can continue to be operated if, for example, there is a short circuit in another part and / or maintenance work has to be carried out.

In an advantageous embodiment of the invention, it is proposed that the electrochemical device has at least one monitoring unit which is electrically connectable and / or connected to the contact element and to the further contact element. The monitoring unit can be permanently or optionally connected to the contact elements. In addition, it is conceivable that the monitoring unit is modular and / or optionally removable. Preferably, the monitoring unit has at least one arithmetic unit. Preferably, the monitoring unit is connected to a plurality of contact elements, particularly preferably to each contact element of the cell unit. Preferably, the monitoring unit has a plurality of input channels, to which in particular in each case at least one contact element or in each case at least one electrochemical cell, advantageously unique, can be assigned and / or assigned. In particular, the monitoring unit is electrically connected to each electrochemical cell of the cell unit to be monitored. The monitoring unit may have at least one user interface such as at least one display, in particular a touch display, and / or at least one input unit, for example a mouse and / or a keyboard and / or a control panel and / or switches and / or buttons and the like. In particular, the monitoring unit can be used to monitor the operation of the Cell unit may be provided. As a result, a reliable operation can advantageously be achieved.

In a particularly advantageous embodiment of the invention it is proposed that the monitoring unit is provided for a determination of at least one single cell parameter, in particular a single cell voltage, by means of the contact elements. In particular, the single-cell parameter is at least one operating state parameter of the electrochemical cell, which can be advantageously determined by means of at least one measurement, for which it is particularly advantageous to contact only two contact elements assigned to the electrochemical cell, in particular its anode and cathode. However, it is also conceivable that the monitoring unit is provided to determine the single cell parameter using at least one additional parameter such as an environmental parameter such as a temperature, a humidity, an air pressure, a fluid temperature, a fluid conductivity or the like. In addition, the monitoring unit can be provided for determining the corresponding environmental parameter. The single cell parameter may also be a conductivity and / or a current and / or a temperature and / or an impedance or the like. The monitoring unit preferably has at least one sensor unit and / or measuring unit for determining the single cell parameter. Particularly preferably, the sensor unit and / or measuring unit is connectable to the input channels and / or in particular permanently connected. The monitoring unit is preferably provided to measure a single voltage, which is different in particular from a total voltage of the cell unit, between any two contact elements. Preferably, the monitoring unit is provided to determine a single-cell voltage, for example the electrochemical cell and / or the further electrochemical cell, based on a potential difference of adjacent contact elements, for example based on a potential difference between adjacent in the stacking direction bipolar plates and / or adjacent in the stacking direction perforated plates or the like, between which, of course, further functional elements, in particular of a different type, can be arranged. As a result, monitoring of individual cells, for example of a cell stack, can advantageously be carried out, it being advantageous to be able to measure individual cell voltages independently of one another.

In addition, it is proposed that the monitoring unit is provided to detect at least one fault operating state based on the single cell parameter and to change at least one operating parameter of the cell unit as a function of an occurrence of the fault operating state, in particular automatically. For example, the fault operating state may include a short circuit of at least one electrochemical cell. In particular, the monitoring unit can be provided to effect at least bridging at least a part of the cell unit. In particular, in this case, the bridging element may be formed as a switch, which is advantageously controlled by the computing unit of the monitoring unit. It is conceivable that the monitoring unit has the bridging element. Alternatively, it is conceivable that the bridging element can be used in addition to the monitoring unit. In particular, the monitoring unit can be provided to electrically connect at least two arbitrary contact elements, with which it is connected, in particular to achieve a corresponding bridging. It is also conceivable for the monitoring unit to control and / or regulate a total voltage and / or a total current and / or a total reaction rate and / or a flow of a produced gas and / or a flow of a reaction fluid and / or a cooling fluid or the like , in particular depending on the single cell parameter, is provided, in particular alternatively or additionally in at least one normal operating state. In addition, it is conceivable that the monitoring unit is provided to at least temporarily apply an additional voltage to at least individual electrochemical cells and / or to reduce a load of at least individual electrochemical cells at least temporarily, for example by realizing a shunt. In addition, it is conceivable that the monitoring unit has at least one AC voltage source, by means of which an AC voltage can be modulated on at least individual electrochemical cells. As a result, total failures due to individual defective cells can advantageously be avoided. Furthermore, as a result, a diverse monitoring and / or controllability can be achieved.

Advantageous properties with respect to a construction can be achieved in particular with an electrolyzer having at least one electrochemical device according to the invention.

In addition, the invention relates to a functional element, in particular a functional cell stack element, preferably the functional element described above, for the electrochemical device. It is proposed that the functional element has at least two contact elements which are each intended to be able to be disconnected optionally. As described above, the functional element advantageously has at least one plate, in particular a metal sheet, with the contact elements. It is conceivable that that functional element has three or four or five or six or even more contact elements, which are arranged in particular along an edge of the functional element, in particular in a view in a direction perpendicular to a main extension plane of the functional element. The contact elements may be arranged along a single edge of the functional element. It is also conceivable that the functional element has several, in particular opposite, edges, each with at least one contact element. Preferably, in at least one assembled state of the functional element, in which it forms, in particular, a part of the cell stack, at least one of the contact elements of the functional element is cut off. In particular, in the mounted state, all but one contact element of the functional element are disconnected. Preferably, the contact elements of the functional element are intended to be either selectively disconnected or to form a contact element of the cell stack. In particular, a position of the contact elements in the cell stack can be selected by suitable separation of other contact elements of the functional element. Preferably, the cell stack is at least partially constructed of functional elements, each having either no contact element or exactly one contact element and their optionally additionally present in a preassembled state contact elements are separated.

The inventive design of the functional element advantageous properties can be achieved in terms of cost efficiency. In addition, an advantageous construction of an electrochemical device, in particular an electrolyzer, can be achieved. Furthermore, an electrochemical device can be provided whose operation can be easily and / or reliably monitored. In addition, a low-cost and / or easy-to-manufacture electrochemical device can be provided. Furthermore, advantageous properties with regard to a simple and / or cost-effective production of components of an electrochemical device can be achieved. Advantageously, operating parameters of parts of an electrochemical device, in particular of individual electrochemical cells, can be reliably measured. Further, a plurality of contact elements can be provided in a small space, which can be made possible in particular single cell measurements on a plurality of adjacent cells. In addition, even very thin single cells can be reliably contacted. In addition, a high reliability and / or a high load capacity of electrical contact elements can be achieved.

In addition, the invention relates to a method for producing a functional element which, in particular as described above, has at least two contact elements arranged at different positions in at least one preassembled state, wherein at least one of the contact elements is severed. Preferably, all but one contact element of the functional element are separated. It is also conceivable that all contact elements of the functional element are separated, for example, if identically designed functional elements are to be used to construct a cell stack, wherein only some electrochemical cells of the cell stack should be individually contactable. Preferably, the method is part of a method for producing an electrochemical device according to the invention.

The inventive method advantageous properties can be achieved in terms of cost efficiency. In addition, an advantageous construction of an electrochemical device, in particular an electrolyzer, can be achieved. Furthermore, an electrochemical device can be provided whose operation can be easily and / or reliably monitored. In addition, a low-cost and / or easy-to-manufacture electrochemical device can be provided. Furthermore, advantageous properties with regard to a simple and / or cost-effective production of components of an electrochemical device can be achieved. Advantageously, operating parameters of parts of an electrochemical device, in particular of individual electrochemical cells, can be reliably measured. Further, a plurality of contact elements can be provided in a small space, which can be made possible in particular single cell measurements on a plurality of adjacent cells. In addition, even very thin single cells can be reliably contacted. In addition, a high reliability and / or a high load capacity of electrical contact elements can be achieved.

The electrochemical device according to the invention, the functional element according to the invention and the method according to the invention are not intended to be limited to the applications and embodiments described above. In particular, the electrochemical device according to the invention, the functional element according to the invention and the method according to the invention for performing a function described herein may have a different number from a number of individual elements and / or components and / or units and / or method steps mentioned herein. In addition, in the value ranges indicated in this disclosure, values lying within the stated limits are also to be disclosed as disclosed and used as desired.

list of figures

Further advantages emerge from the following description of the drawing. In the drawings, an embodiment of the invention is shown. The drawings, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

• 1 einen Elektrolyseur mit einer Elektrochemievorrichtung in einer schematischen Seitenansicht,
• 2 die Elektrochemievorrichtung mit einem Überbrückungselement in einer schematischen Seitenansicht,
• 3 ein funktionelles Element der Elektrochemievorrichtung in einem vormontierten Zustand in einer schematischen Draufsicht und
• 4 ein schematisches Ablaufdiagramm eines Verfahrens zur Herstellung der Elektrochemievorrichtung.

Show it:

• 1 an electrolyzer with an electrochemical device in a schematic side view,
• 2 the electrochemical device with a bridging element in a schematic side view,
• 3 a functional element of the electrochemical device in a preassembled state in a schematic plan view and
• 4 a schematic flow diagram of a method for producing the electrochemical device.

Description of the embodiments

The 1 shows an electrochemical device 10 in a schematic side view. In the present case, the electrochemical device 10 Part of an electrolyzer 44 , Components such as a fluid supply, a housing and the like of the electrolyzer 44 are in the 1 not shown. However, it may of course include the like. The electrochemical device 10 is designed in the present case as an electrolysis device. However, as mentioned above, it is also conceivable that the electrochemical device 10 a fuel cell device, a measuring device, a galvanizing device or the like.

The electrochemical device 10 has a cell unit 12 on, the at least one electrochemical cell 14 having. Furthermore, the cell unit comprises 12 at least one more electrochemical cell 16 , In the present case, the cell unit 12 a variety of electrochemical cells 14 . 16 on, for reasons of clarity schematically shown only twelve and not all provided with reference numerals. In addition, the electrochemical cells 14 . 16 the cell unit 12 in the 1 not shown to scale. In particular, the electrochemical cells 14 . 16 the cell unit 12 be much flatter than in the schematic representation of 1 , For example, the cell unit 12 20 or 30 or 50 or 100 or 150 or 200 electrochemical cells 14 . 16 include.

The cell unit 12 has a cell stack 34 a plurality of stacked electrochemical cells 14 . 16 includes. In the present case, all electrochemical cells 14 . 16 the cell unit 12 to the cell stack 34 stacked. Furthermore, in the present case, the electrochemical cells 14 . 16 the cell unit 12 at least substantially identical to each other. The cell stack 34 is in this case an electrolysis stack. The electrochemical cells 14 . 16 the cell unit 12 are in a stacking direction 36 stacked. The stacking direction 36 corresponds to a stack thickness direction of the cell stack 34 , The stacking direction 36 in this case runs perpendicular to a main extension plane of the electrochemical cell 14 , Further, in the present case, main extension planes of the electrochemical cells 14 . 16 the cell unit 12 arranged parallel to each other.

The cell unit 12 has a first end plate 50 and a second end plate 52 on. The first end plate 50 and the second end plate 52 limit the electrochemical cells 14 . 16 of the cell stack 34 to opposite sides of the cell stack 34 out. The end plates 50 . 52 are connected to each other for example by means not shown connecting struts and act on the electrochemical cells 14 . 16 of the cell stack 34 with a pressure force, which counteracts in particular a pressure due to formation of hydrogen gas and / or oxygen gas or in particular a tightness of the juxtaposed electrochemical cells 14 . 16 with each other and / or a tightness of the respective electrochemical cell 14 . 16 accomplished or at least contributes to this.

The electrochemical device 10 has connecting elements 22 . 24 for connection to a power supply 26 on. In a normal operating state, the cell unit becomes 12 via the connection elements 22 . 24 supplied with electrical power. A total voltage lies between a frontmost electrochemical cell 58 especially on the first end plate 50 is present, and a rearmost electrochemical cell 60 especially on the second end plate 52 is present at. At individual electrochemical cells 14 . 16 . 58 . 60 the cell unit 12 is in the normal operating state in each case a voltage between about 1 V and about 2.5 V, as especially mentioned above.

The electrochemical cell 14 has a thickness of at most 5 mm. In the present case, the electrochemical cells 14 . 16 . 58 . 60 the cell unit 12 a thickness of about 1.8 mm, with any other thicknesses are conceivable.

The electrochemical cell 14 has at least one contact element 18 on, that of a connecting element 22 . 24 for a power supply 26 is different. The contact element 18 is from an exterior of the cell unit 12 accessible. In the present case, the contact element 18 from an exterior of the electrochemical device 10 accessible. The contact element 18 is outside an active interior of the electrochemical cell 14 and / or outside an active interior of the cell unit 12 arranged. The contact element 18 allows electrical contacting of the electrochemical cell 14 , in particular its anode or its cathode.

Furthermore, the further electrochemical cell has 16 at least one further contact element 20 on. In the present case, each of the electrochemical cells exhibits 14 . 16 . 58 . 60 the cell unit 12 in each case at least one contact element 18 . 20 on, with the contact elements 18 . 20 For reasons of clarity, not all are provided with reference numerals. It is also conceivable that only some of the electrochemical cells 14 . 16 . 58 . 60 the cell unit 12 contact elements 18 . 20 exhibit. In the present case are a particular electrochemical cell 14 . 16 . 58 . 60 two contact elements each 18 . 20 of which in particular one at an anode potential and one at a cathode potential of the corresponding electrochemical cell 14 . 16 . 58 . 60 lies. In particular, it is the case of a particular electrochemical cell 14 . 16 . 58 . 60 associated contact elements 18 . 20 each to a contact element of the corresponding electrochemical cell 14 . 16 . 58 . 60 as well as a contact element 18 . 20 an immediately adjacent other electrochemical cell 14 . 16 . 58 . 60 , In particular, in this way a specific contact element 18 . 20 two immediately adjacent electrochemical cells 14 . 16 . 58 . 60 associated with the corresponding contact element 18 . 20 on an anode potential of an electrochemical cell 14 . 16 . 58 . 60 which is a cathode potential of the other electrochemical cell 14 . 16 . 58 . 60 equivalent. For example, in the present case, the electrochemical cell 14 the contact element 18 as well as the further contact element 20 assigned. In addition, in the present case, the further contact element 20 the electrochemical cell 14 and the further electrochemical cell 16 assigned.

The contact element 18 is formed in the present case as a blade contact element. The contact element 18 has a thickness of less than 1 mm, preferably less than 0.5 mm. The contact element 18 has a main extension plane that is at least substantially perpendicular to the stacking direction 36 runs. In the present case, the contact element protrudes 18 laterally out of the cell stack 34 in a direction perpendicular to the stacking direction 36 , Furthermore, the contact element 18 formed in the present case of a metal, in particular of titanium, wherein, as mentioned above, other materials are conceivable. The further contact element 20 is at least substantially identical to the contact element 18 educated.

The contact element 18 and the further contact element 20 are arranged offset to one another, in particular as viewed along the stacking direction 36 , In the present case, the contact element 18 and the further contact element 20 on the same side of the cell stack 34 arranged. It is also conceivable that the contact element 18 and the further contact element 20 on different sides of the cell unit 12 and / or the cell stack 34 are arranged. The contact element 18 is in the present case in a view perpendicular to the stacking direction 36 above a longitudinal axis 80 of the cell stack 34 arranged. The further contact element 20 is in the present case in the view perpendicular to the stacking direction 36 below the longitudinal axis 80 of the cell stack 34 arranged. However, the arrangement shown is purely exemplary. In particular, any other staggered arrangements of contact elements 18 . 20 conceivable.

Several, in the present case all, electrochemical cells 14 . 16 . 58 . 60 of the cell stack 34 each have at least one contact element 18 . 20 on, wherein at least some of the contact elements 18 . 20 arranged offset from each other. In particular, each adjacent contact elements 18 . 20 arranged offset from one another. In the present case, the contact elements 18 . 20 each with respect to the stacking direction 36 at the same position of their corresponding electrochemical cell 14 . 16 . 58 . 60 arranged, so in particular a distance between immediately adjacent contact elements 18 . 20 a thickness of the electrochemical cells 14 . 16 . 58 . 60 equivalent. But there are also other arrangements with respect to the stacking direction 36 conceivable, so that, for example, immediately adjacent contact elements 18 . 20 on opposite sides of their respective electrochemical cells 14 . 16 . 58 . 60 can be arranged.

In a view along the stacking direction 36 are at least some of the contact elements 18 . 20 of the cell stack 34 arranged in several rows. In the 1 are each longitudinal axes 62 . 64 . 66 the rows marked. In the 1 three rows are shown, with any other number is conceivable. It is also conceivable that the Rows on a common side of the cell unit 12 are arranged and / or on different, in particular opposite, sides of the cell unit 12 , Furthermore, in the present case, the contact elements 18 . 20 arranged in a staircase and / or associated with the rows in a regular pattern. Here, any arrangements are also conceivable.

The electrochemical device 10 has a monitoring unit 42 on that with the contact element 18 and the further contact element 20 electrically connected. In the present case, the monitoring unit 42 with each contact element 18 . 20 the cell unit 12 connected. The monitoring unit 42 is to a determination of at least one single cell parameter by means of the contact elements 18 . 20 intended. For example, the single cell parameter may be a single cell voltage, a current, an impedance, or the like. For example, in the present case, a single voltage of the electrochemical cell 14 by means of a measurement between the contact element 18 and the further contact element 20 applied voltage can be determined. The monitoring unit 42 is intended in the present case to carry out a corresponding measurement.

The monitoring unit 42 is intended to detect at least one fault operating state based on the single cell parameter and at least one operating parameter of the cell unit 12 depending on an occurrence of the error operating condition. For example, the monitoring unit 42 be provided to short-circuited parts, in particular defective electrochemical cells, the cell unit 12 to bridge, in particular via corresponding contact elements. An operating current in this case flows at least in sections through a bridging section, not shown, of the monitoring unit 42 , It is also conceivable that the monitoring unit 42 is provided for controlling and / or regulating at least one operating parameter in at least one normal operating state. For example, the monitoring unit 42 be provided to adjust a fluid supply, a power supply, a temperature, a gas production rate or the like depending on at least one determined single cell parameter.

In principle, it is conceivable that the electrochemical device 10 no monitoring unit 42 having. It is also conceivable that instead of or additional to the monitoring unit 42 any other measuring devices with at least one of the contact elements 18 . 20 connected and / or connectable, for example, for maintenance purposes, during commissioning, in a quality control, when testing individual electrochemical cells 14 . 16 . 58 . 60 or similar.

The 2 shows the electrochemical device 10 in a schematic side view, wherein the monitoring unit 42 for reasons of clarity is not shown. The electrochemical device 10 has a, in particular optionally attachable, bridging element 38 on, which is intended, in at least one operating state, an electrical connection between the contact element 18 and at least one other contact element 40 to make at least part of the cell unit 12 to bridge. In particular, the invention also includes a system with the electrochemical device 10 and the bridging element 38 , In the present case, the bridging element 38 on the contact elements 18 . 40 attachable, for example manually, in particular by a user. The bridging element 38 may comprise a flexible conductor section, for example a cable. In particular, the bridging element 38 intended to any contact elements 18 . 20 . 40 to connect together, preferably at least two. By means of the bridging element 38 can be single electrochemical cells 14 . 16 . 58 . 60 or also a partial stack of the cell unit 12 and / or the cell stack 34 be temporarily bridged, in particular. Likewise, a bridging of short-circuited areas is conceivable, in particular as an alternative to the monitoring unit 42 or in addition to this.

The 3 shows a functional element 28 the electrochemical cell 14 in a schematic plan view. The functional element 28 is formed plate-like. The functional element 28 is formed as a cell stack element. In the present case, the cell stack comprises 34 a plurality of cell stacking elements which, as mentioned above, are arranged in repeating units and thus the electrochemical cells 14 . 16 . 58 . 60 and the cell stack 34 form. The functional element 28 may be, for example, a bipolar plate, a perforated plate, a screen plate, a pressure pad or the like.

The functional element 28 has the contact element 18 on. Preferably, the functional element is 28 at least partially metallic. Particularly preferred is the functional element 28 in a mounted state of the electrochemical cell 14 on their anode potential or on their cathode potential, so that a corresponding potential on the functional element 28 can be tapped.

In the present case, each of the electrochemical cells exhibits 14 . 16 . 58 . 60 the cell unit 12 that is a contact element 18 . 20 comprises, an analogously formed functional element 28 with the corresponding contact element 18 . 20 on. Preferably, the functional elements 28 with the contact elements 18 . 20 of the same type. But it is, in particular if a variable distance in the stacking direction 36 between contact elements is desired, conceivable that contact elements 18 . 20 on functional elements 28 different types are attached.

The functional element 28 has a functional component 30 on, at least partially integral with the contact element 18 connected is. The functional component 30 represents an active area 68 for an active interior of the electrochemical cell 14 ready. For example, the functional component 30 an electrode surface and / or a fluid distribution layer or the like. The contact element 18 is as a nose-like tab of a plate 32 educated. In the present case, the plate 32 a component of the functional component 30 and / or train them. For example, the plate 32 a sheet, in particular a titanium sheet be. Preferably, the contact element 18 and the plate 32 formed in one piece. Particularly preferred are the contact element 18 and the plate 32 from a common blank, in particular a common sheet produced. The contact element is preferred 18 and the plate 32 formed as a stamped part and / or as a stamped and bent part.

In the 3 is the functional element 28 shown in a preassembled state. In the pre-assembled state has the functional element 28 at least two contact elements 18 . 46 . 48 which are each intended to be selectively separated. In the present case, the functional element 28 three contact elements 18 . 46 . 48 on, which are formed in particular at least substantially identical. Of course, any other number of contact elements 18 . 46 . 48 conceivable. The contact elements 18 . 46 . 48 stand over an edge 70 of the functional element 28 over and are especially along the edge 70 severable. It is conceivable that corresponding embossments and / or predetermined breaking points and / or perforations or the like are provided. By suitable separation of contact elements 18 . 46 . 48 can be a remaining contact element 18 or optionally several remaining contact elements 18 . 46 . 48 the rows in which the contact elements 18 . 20 the cell unit 12 are arranged to be assigned.

The 4 shows a schematic flow diagram of a method for producing the electrochemical device 10 , The method includes a method 72 for the production of the functional element 28 , In at least one process step 74 becomes the functional element 28 with the contact elements 18 . 46 . 48 manufactured. Preferably, the functional component 30 and the contact elements 18 . 46 . 48 in at least one joint step, for example by means of a punching made. In at least one process step 76 becomes at least one of the contact elements 46 . 48 separated. In the present case, two of the three contact elements 18 . 46 . 48 separated, so in particular only the contact element 18 remains. A separation of contact elements 46 . 48 takes place according to an arrangement of contact elements 18 . 20 in the cell stack 34 , Of course, it is conceivable, all contact elements 18 . 46 . 48 if, for example, a corresponding electrochemical cell 14 . 16 . 58 . 60 should have no contact element. In addition, it is conceivable, several contact elements 18 . 46 . 48 not separate, so the functional element 28 in a mounted state, several contact elements 18 . 46 . 48 to identify, for example, a multiple contact, such as from different sides of the cell unit 12 or at the same time by a monitoring unit 42 and an additionally attached bridging element 38 to enable.

In a further process step 78 becomes the functional element 28 stacked with other functional elements to the cell stack 34 train. In principle, of course, conceivable contact elements 18 . 46 . 48 only after production of a cell stack 34 separate.

Claims (16)

Electrochemical device, in particular electrolysis device, in particular a polymer electrolyte membrane electrolysis device, having at least one cell unit (12) comprising at least one electrochemical cell (14), characterized in that the electrochemical cell (14) has at least one contact element (18) which is connected by a connecting element (22, 24) for a power supply (26) is different. Electrochemical device after Claim 1 , characterized in that the electrochemical cell (14) comprises at least one functional element (28), in particular a functional cell stack element, which has the contact element (18). Electrochemical device after Claim 2 , characterized in that the contact element (18) and at least one functional component (30) of the functional element (28) are at least partially connected in one piece. Electrochemical device according to one of the preceding claims, characterized in that the contact element (18) as a nose-like projection of a plate (32), in particular a sheet is formed. Electrochemical device according to one of the preceding claims, characterized in that the electrochemical cell (14) has a thickness of at most 5 mm, advantageously of at most 3 mm and particularly advantageously of at most 2 mm. Electrochemical device according to one of the preceding claims, characterized in that the cell unit (12) has at least one further electrochemical cell (16) with at least one further contact element (20). Electrochemical device after Claim 6 , characterized in that the contact element (18) and the further contact element (20) are arranged offset from one another. Electrochemical device according to one of the preceding claims, characterized in that the cell unit (12) comprises at least one cell stack (34) with a plurality of stacked arranged electrochemical cells (14, 16) each having at least one contact element (18, 20), wherein at least some of Contact elements (18, 20) are arranged offset from one another. Electrochemical device after Claim 8 characterized in that at least some of the contact elements (18, 20) of the cell stack (34) are arranged in a plurality of rows as viewed along a stacking direction (36). Electrochemical device according to one of Claims 6 to 9 characterized by at least one bridging element (38) which is provided, in at least one operating state, to establish an electrical connection between the contact element (18) and at least one other contact element (40) in order to bridge at least a part of the cell unit (12). Electrochemical device according to one of the preceding claims, characterized by at least one monitoring unit (42) which is electrically connectable and / or connected to the contact element (18) and to the further contact element (20). Electrochemical device after Claim 11 , characterized in that the monitoring unit (42) is provided for a determination of at least one single cell parameter, in particular a single cell voltage, by means of the contact elements (18, 20). Electrochemical device after Claim 12 , characterized in that the monitoring unit (42) is provided to detect at least one error operating state based on the single cell parameter and to change at least one operating parameter of the cell unit (12) in dependence on an occurrence of the error operating state. Electrolyzer with at least one electrochemical device (10) according to one of the preceding claims. Functional element, in particular functional cell stack element, for an electrochemical device (10) according to one of the Claims 1 to 13 characterized by at least two contact elements (18, 46, 48), which are each provided to be selectively separated. Process for the preparation of a functional element (28), in particular according to Claim 15 , an electrochemical device (10), in particular according to one of Claims 1 to 13 which has at least two contact elements (18, 46, 48) arranged at different positions in at least one pre-assembled state, wherein at least one of the contact elements (46, 48) is cut off.

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