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DE-102024133258-A1 - RECIRCULATION DEVICE WITH PISTON

DE102024133258A1DE 102024133258 A1DE102024133258 A1DE 102024133258A1DE-102024133258-A1

Abstract

A recirculation device (1) for a fuel cell (10) comprising at least two pistons (4, 4') which are arranged to pump fluid in at least one fluid circuit of the fuel cell (10).

Inventors

  • Oliver Harr
  • Philipp Hausmann

Assignees

  • CELLCENTRIC GMBH & CO. KG

Dates

Publication Date
20260513
Application Date
20241113

Claims (11)

  1. Recirculation device (1) for a fuel cell (10) comprising at least two pistons (4, 4') which are arranged to pump fluid in at least one fluid circuit of the fuel cell (10).
  2. Recirculation device (1) according to the preceding claim, characterized in that the at least two pistons, in particular each, have a supply of liquid, wherein the pistons are arranged so that a hydrostatic bearing of the piston can be formed with the help of the liquid.
  3. Recirculation device (1) according to one of the preceding claims, characterized in that the at least two pistons (4, 4') have a membrane, wherein the membrane has a selectivity, in particular for nitrogen.
  4. Recirculation device (1) according to one of the preceding claims, characterized in that the at least two pistons (4, 4') have at least one spring element which is configured to move and/or return the piston (4, 4').
  5. Recirculation device (1) according to the preceding claim, characterized in that the spring element comprises a shape memory alloy which is particularly designed to actuate the spring element.
  6. Recirculation device (1) according to one of the preceding claims, characterized in that the recirculation device (1) has a water container, in particular a heatable one, which is configured to be supplied with water, in particular deionized water, from an anode side of the fuel cell (10), wherein the supply is configured to be supplied from the water container.
  7. Recirculation device (1) according to one of the preceding claims, characterized in that the recirculation device (1) has a sensor (9) which is configured to detect a position of the piston (4, 4') and/or a pressure in a piston chamber (4, 4') associated with the piston (4, 4').
  8. Method for operating a recirculation device (1), in particular a recirculation device (1) according to one of the Claims 1 until 6 , comprising: - admitting a fluid into a first chamber (5) of the first piston (2); - detecting a pressure in a second chamber (6) of the first piston (2); and - opening a valve of the second chamber (6), based on the detected pressure of the second chamber (6).
  9. Method according to the preceding claim, characterized in that the method further comprises: - introducing a fluid into a third chamber (7) of the second piston (2); - detecting a pressure in a fourth chamber (8) of the second piston (2); and - opening a valve of the fourth chamber (8) based on the detected pressure of the fourth chamber (8).
  10. Method according to the preceding claim, characterized in that the opening of the valve of the fourth chamber (8) depends on the opening of the valve of the second chamber (6).
  11. Recirculation system for a vehicle with at least one fuel cell (10), comprising at least one recirculation device (1) according to one of the Claims 1 until 7 .

Description

The present invention relates to a recirculation device, a recirculation system and a method for operating a recirculation device. Fluids and gases are typically moved using compressors, such as side-channel compressors or turbo compressors. These usually operate at high speeds or have high power consumption, which is often associated with poor system efficiency, excessive bearing wear, or complicated and/or insufficient bearing lubrication. In particular, it is an object of the invention to further improve a recirculation device, and in particular to avoid or improve at least some of the disadvantages of the prior art. The solution to this problem is achieved according to the teaching of the independent claims. Various embodiments and further developments of the invention are the subject of the dependent claims. According to one embodiment of the invention, a recirculation device, particularly for a fuel cell or fuel cell system, is provided, furthermore specifically for recirculating a fluid of the fuel cell or fuel cell system. In one embodiment, the recirculation device has at least one piston. In another embodiment, the recirculation device has at least two pistons. In an alternative embodiment, the recirculation device has exactly two pistons. The piston(s) are configured in one embodiment to convey and/or recirculate fluid in the recirculation device, in particular to move it through the recirculation device, especially in a circuit for at least one fluid, which in one embodiment is encompassed by the recirculation device. In one embodiment, the recirculation device for a fuel cell comprises at least two pistons configured for conveying fluid in at least one fluid circuit of the fuel cell. In one embodiment, fluid can be conveyed by means of a fluid pressure differential that can be applied to piston chambers of the pistons in interdependent piston chambers of the pistons and/or a fluid pressure differential that can be applied between the piston chambers of the pistons. In one embodiment, the pistons are fluidically interconnected such that a conveying effect of the fluid(s) (into or out of the piston chambers) can be achieved by means of pressure differences (in the respective piston chambers), or the pistons can be used for this purpose. In one embodiment, the recirculation device is configured to convey (at least) one fluid by means of a (fluid) pressure, in particular from a pressurized gas storage tank, and further in particular from a hydrogen tank, especially a cryogenic one, and/or a (fluid) pressure from a fuel cell, in particular from its anode side, and/or a pressure from an anode separator (ACO). In one embodiment, the at least two pistons, in particular the piston chambers associated with each piston, of the recirculation device are fluidically connected to one another in such a way that a fluid is conveyed from the first piston, in particular from one of the piston chambers of the first piston, into, in particular, a piston chamber of the second piston, especially when the piston moves or is moved. In another embodiment, fluid is conveyed from or through the first piston via a fuel cell into the second piston and recycled from or through the second piston into the fuel cell. "First" and "second," in particular any numbering used herein, are to be understood without limitation of generality. Advantageously, in one embodiment, a recirculation device can be realized that can be operated, at least substantially, without loss of bypass gas, and in particular can implement a pumping motion that recirculates a gas or fluid, especially at pressures above normal pressure, at least substantially, without loss of bypass gas or bypass fluid, and is used for this purpose. Advantageously, in one embodiment, a recirculation of a fluid can be enabled that, in a piston pump-like manner, recirculates at least one fluid, in particular different fluids, especially in a circuit that includes a fuel cell, and/or receives at least one fluid from a fuel cell and/or delivers at least one fluid to the fuel cell, and furthermore, in particular, delivers (to be recirculated) fuel from the fuel cell back into the fuel cell and/or delivers (new) fuel into the fuel cell. Advantageously, this allows for a smaller energy consumption/effort for a recirculation device in one embodiment, in particular reducing energy consumption, especially of the periphery, of a fuel cell or fuel cell system. The term "piston" as used herein shall be understood in particular as a component that is located in a cavity (the recirculation device) or piston chamber specifically designed for the component, in particular a fluid-tight cavity, in particular a A cylinder slides back and forth, particularly by means of pressure, wherein the piston, in one embodiment, particularly displaces a fluid and/or gas, particularly hydrogen. In one embodiment, the "piston" itself forms the cavity; in particular, the piston can comprise (at least) a bellow