Abstract: The invention relates to a liquid separator (100), in particular for a fuel cell device, the liquid separator (100) comprising the following: a fluid-conducting channel (104), a collection region (106) for collecting liquid originating from a fluid that is conducted in the fluid-conducting channel (104), a liquid passage (110) branching off from the fluid-conducting channel (104) and a liquid collection region (112) into which the liquid passage (110) leads.

Abstract: An electrochemical device is provided, including a stack of a plurality of electrochemical units, at least one medium channel extending along a stack direction, at least one flow field via which a medium is able to flow transversely to the stack direction from the medium channel to another medium channel, and at least one connecting channel via which the flow field and the medium channel are in fluidic connection. The connecting channel has a medium channel-side mouth opening extending along a circumferential direction of the flow field from a first medium channel-side rim to a second medium channel-side rim, and a flow field-side mouth opening extending along the circumferential direction from a first to a second flow field-side rim. At least one of the flow field-side rims is offset away from the respective other flow field-side rim along the circumferential direction in relation to one of the medium channel-side rims.

Abstract: A method is provided for producing an electrochemically active unit that includes a membrane and at least one assembly, which includes a gas diffusion layer and a sealing element produced on the gas diffusion layer. The method is reliably performable with less expenditure on process apparatuses and process time and includes the following: producing the sealing element on the gas diffusion layer; connecting the sealing element and/or the gas diffusion layer to a support element; and assembling the membrane and the at least one assembly, which includes the gas diffusion layer and the sealing element, to form the electrochemically active unit.

Abstract: An assembly for an electrochemical device is provided, including a gas diffusion layer and a sealing element produced on the gas diffusion layer. The sealing element includes an inner sealing region fixed to the gas diffusion layer and an outer sealing region connected to the gas diffusion layer via the inner sealing region. The assembly has minimal warpage without the temperature in the injection molding tool having to be lowered and/or a geometric pre-compensation of the warpage of the sealing element in the inner sealing region. The sealing element includes a relief region arranged between the inner and outer sealing regions and a) includes a relief opening extending through the sealing element and/or b) has a smallest height (he), which is smaller than both one fourth of the greatest height (HI) of the inner sealing region and one fourth of the greatest height (HA) of the outer sealing region.

Abstract: A fuel cell device is provided, including a fuel cell stack, which includes a plurality of fuel cell units following each other in a stacking direction, and two end plates, between which the fuel cell stack is arranged. With the fuel cell device, harmful effects from hydrogen exiting the fuel cell units are avoided without making access to the fuel cell units impossible or causing a disproportionately large maintenance expenditure. The fuel cell device includes an enclosure which surrounds the fuel cell stack and the end plates, wherein the free remaining volume that remains within the enclosure between the enclosure, the fuel cell stack, and the end plates is less than 20% of the internal volume of the enclosure.

Abstract: In order to provide an electrochemically active unit for an electrochemical device including a membrane electrode assembly, at least one gas diffusion layer and a seal that is linked to at least one of the at least one gas diffusion layers, in the manufacture whereof as even as possible a construction of the penetration region in which the gas diffusion layer of the electrochemically active unit is penetrated by the sealing material of the seal over the periphery of the gas diffusion layer is achievable, the seal includes a linking region, a distribution region and a connection region that connects the linking region and the distribution region to one another, wherein the connection region has a minimum height that is less than a quarter of the maximum height of the distribution region and less than a quarter of the maximum height of the linking region.

Abstract: An electrochemical device comprises a stack consisting of a plurality of electrochemical units which succeed one another along a stack direction and which each include a membrane electrode arrangement, a bipolar plate and at least one sealing element, at least one medium channel which extends along the stack direction, a flow field through which a medium can flow from the medium channel to another medium channel, and a connection channel through which the flow field and the medium channel are in fluid connection with one another, wherein the sealing arrangement includes a connection channel region in which the sealing arrangement crosses the connection channel, and at least one neighboring region which is located in front of or behind the connection channel region in the longitudinal direction of the sealing arrangement, wherein the sealing arrangement has a lower average height in the connection channel region than in the neighboring region.

Abstract: A method for producing a multi-layer bipolar plate for an electrochemical device is disclosed. The method includes producing at least one sealing element made of an elastic material on a first bipolar plate layer of the bipolar plate; connecting the first bipolar plate layer with the sealing element produced thereon and a second bipolar plate layer of the bipolar plate by welding along at least one connection welding seam, in which method an impairment to the sealing element produced on the first bipolar plate layer as a result of a subsequent welding operation can be reliably avoided and the freedom of design of the electrochemical unit is preferably increased, and that during the welding operation, the second bipolar plate layer faces toward a welding energy source and that during the welding operation, a weld pool produced by the welding energy source does not completely penetrate the first bipolar plate layer.

Abstract: A fuel cell device is provided, including a media system for supplying fluid media to electrochemical units of the fuel cell device and/or for discharging fluid media from the electrochemical units of the fuel cell device, wherein the media system includes at least one valve to which, in a standard operating state of the fuel cell device, an electrical standard input power is suppliable in order to maintain the valve in a desired valve state. The fuel cell device is able to be reliably started with as little effort as possible, even under frost conditions. The fuel cell device is switchable into a heating operating state in which an electrical heating input power that is greater than the electrical standard input power is suppliable to the at least one valve.

Abstract: A bipolar plate for an electrochemical device, including a first bipolar plate layer and a second bipolar plate layer joined by a weld seam arrangement, wherein the first bipolar plate layer has a first and a second medium passage opening. The weld seam arrangement includes a first and a second medium channel weld seam, and a connecting weld seam which crosses the first and the second medium channel weld seams. Either a) the connecting weld seam is produced by a welding energy source which the first bipolar plate layer faced during the welding process, and the weld seam end of the connecting weld seam lies within the medium-conducting region of the bipolar plate which is surrounded by the first medium channel weld seam, and/or b) the connecting weld seam crosses the first medium channel weld seam and/or the second medium channel weld seam at least twice in each case.

Abstract: An assembly for an electrochemical device is provided, including a gas diffusion layer and a sealing element produced on the gas diffusion layer. The sealing element includes an inner sealing region fixed to the gas diffusion layer and an outer sealing region connected to the gas diffusion layer via the inner sealing region. The assembly has minimal warpage without the temperature in the injection molding tool having to be lowered and/or a geometric pre-compensation of the warpage of the sealing element in the inner sealing region. The sealing element includes a relief region arranged between the inner and outer sealing regions and a) includes a relief opening extending through the sealing element and/or b) has a smallest height (he), which is smaller than both one fourth of the greatest height (H1) of the inner sealing region and one fourth of the greatest height (HA) of the outer sealing region.

Abstract: A method is provided for producing an electrochemically active unit that includes a membrane and at least one assembly, which includes a gas diffusion layer and a sealing element produced on the gas diffusion layer. The method is reliably performable with less expenditure on process apparatuses and process time and includes the following: producing the sealing element on the gas diffusion layer; connecting the sealing element and/or the gas diffusion layer to a support element; and assembling the membrane and the at least one assembly, which includes the gas diffusion layer and the sealing element, to form the electrochemically active unit.

Abstract: An electrochemical device is provided, including: a stack of a plurality of electrochemical units succeeding one another along a stacking direction, each including an electrochemically active membrane electrode arrangement, a bipolar plate, and a sealing system; at least one medium channel extending along the stacking direction through a plurality of electrochemical units; and a flow field via which a medium from the medium channel can flow transversely to the stacking direction to another medium channel. The sealing system includes a flow field sealing arrangement extending around a flow field, and a medium channel sealing arrangement extending around a medium channel. The flow field sealing arrangement is fixed to the membrane electrode arrangement and the medium channel sealing arrangement is fixed to the bipolar plate.

Abstract: An electrochemical device is provided, including a stack of a plurality of electrochemical units, at least one medium channel extending along a stack direction, at least one flow field via which a medium is able to flow transversely to the stack direction from the medium channel to another medium channel, and at least one connecting channel via which the flow field and the medium channel are in fluidic connection. The connecting channel has a medium channel-side mouth opening extending along a circumferential direction of the flow field from a first medium channel-side rim to a second medium channel-side rim, and a flow field-side mouth opening extending along the circumferential direction from a first to a second flow field-side rim. At least one of the flow field-side rims is offset away from the respective other flow field-side rim along the circumferential direction in relation to one of the medium channel-side rims.

Abstract: To provide a flow element which in particular is used as a component of a bipolar plate in electrochemical devices, which is stable and permits efficient flow guiding, it is proposed that the flow element comprises a plate-like main body that is formed as a shaped sheet metal product and has a channel structure, wherein the channel structure comprises a plurality of channels which are formed by recesses in the main body and are separated from one another by raised portions of the main body, wherein there is provided at least one region with normal level difference that defines, with respect to a height direction running perpendicular to two main directions of extent of the main body, a height difference between a recess and an adjoining raised portion, wherein there is provided at least one region with reduced level difference, in which a height difference between a recess and an adjoining raised portion is less than the normal level difference, wherein the at least one region with reduced level difference co

Abstract: An electrochemical device is provided that includes a stack of a plurality of electrochemical units that succeed one another in a stacking direction and each include an electrochemically active membrane electrode assembly, at least one gas diffusion layer and a bipolar plate having at least one flow field, in which at least one flow field is sealed off simply and reliably and the occurrence of parasitic flows is prevented, wherein at least one bipolar plate has at least one edge web, which borders a flow field of the bipolar plate and is in contact with a gas diffusion layer adjacent to the bipolar plate, and wherein the electrochemical device further includes at least one flow field seal element that seals off the flow field bordered by the edge web and is in contact with the edge web and in contact with the gas diffusion layer.

Abstract: In order to provide an electrochemically active unit for an electrochemical device including a membrane electrode assembly, at least one gas diffusion layer and a seal that is linked to at least one of the at least one gas diffusion layers, in the manufacture whereof as even as possible a construction of the penetration region in which the gas diffusion layer of the electrochemically active unit is penetrated by the sealing material of the seal over the periphery of the gas diffusion layer is achievable, the seal includes a linking region, a distribution region and a connection region that connects the linking region and the distribution region to one another, wherein the connection region has a minimum height that is less than a quarter of the maximum height of the distribution region and less than a quarter of the maximum height of the linking region.

Abstract: A fuel cell device is provided, including a fuel cell stack, which includes a plurality of fuel cell units following each other in a stacking direction, and two end plates, between which the fuel cell stack is arranged. With the fuel cell device, harmful effects from hydrogen exiting the fuel cell units are avoided without making access to the fuel cell units impossible or causing a disproportionately large maintenance expenditure. The fuel cell device includes an enclosure which surrounds the fuel cell stack and the end plates, wherein the free remaining volume that remains within the enclosure between the enclosure, the fuel cell stack, and the end plates is less than 20% of the internal volume of the enclosure.

Abstract: A fuel cell device is provided, including a media system for supplying fluid media to electrochemical units of the fuel cell device and/or for discharging fluid media from the electrochemical units of the fuel cell device, wherein the media system includes at least one valve to which, in a standard operating state of the fuel cell device, an electrical standard input power is suppliable in order to maintain the valve in a desired valve state. The fuel cell device is able to be reliably started with as little effort as possible, even under frost conditions. The fuel cell device is switchable into a heating operating state in which an electrical heating input power that is greater than the electrical standard input power is suppliable to the at least one valve.

Abstract: A bipolar plate for an electrochemical device, including a first bipolar plate layer and a second bipolar plate layer joined by a weld seam arrangement, wherein the first bipolar plate layer has a first and a second medium passage opening. The weld seam arrangement includes a first and a second medium channel weld seam, and a connecting weld seam which crosses the first and the second medium channel weld seams. Either a) the connecting weld seam is produced by a welding energy source which the first bipolar plate layer faced during the welding process, and the weld seam end of the connecting weld seam lies within the medium-conducting region of the bipolar plate which is surrounded by the first medium channel weld seam, and/or b) the connecting weld seam crosses the first medium channel weld seam and/or the second medium channel weld seam at least twice in each case.