The present disclosure is directed to a fuel cell test system and, more particularly, to a fuel cell test system and associated apparatus incorporating an integral heated fuel cell test chamber.
Fuel cell test systems have been developed to perform various functions, such as facilitating the operation of a test subject fuel cell by supplying controlled amounts of fuel and oxidant to the test subject fuel cell, humidifying the gaseous fuel and oxidant streams being supplied to the test subject fuel cell and evaluating the performance of the test subject fuel cell by measuring the current, voltage and/or other operational characteristics generated by the test subject fuel cell under operating conditions.
Fuel cell test systems typically employ elongated supply or feed lines to connect the fuel cell test system to an external test subject fuel cell. The external test subject fuel cell may be heated by cartridge heaters or the like to the desired operating temperature. However, such systems may develop cold spots in the test subject fuel cell or the supply lines supplying the fuel and/or oxidant from the fuel cell test system to the test subject fuel cell, which may cause condensate formation in the supply lines. Condensate formation may adversely impact the reliability of the test data.
Accordingly, there is a need for a fuel cell test system capable of avoiding the problems associated with condensate formation in the test subject fuel cell and/or the feedstock supply lines supplying fuel and oxidant to the test subject fuel cell. In particular, there is a need for a fuel cell test system having an integral heated test chamber capable of receiving and maintaining the test subject fuel cell and associated feedstock supply lines at the desired temperature, thereby reducing the risk of condensate formation and other negative implications associated with temperature variation.
In one aspect, the disclosed fuel cell test system may include a controller, a housing defining a test chamber, a test subject fuel cell positioned in the test chamber, the test subject fuel cell being in communication with the controller to provide the controller with signals indicative of a performance of the test subject fuel cell, a fuel feed in communication with the test subject fuel cell, the fuel feed having a temperature, a humidity, a flow rate and a pressure, wherein at least one of the temperature, the humidity, the flow rate and the pressure of the fuel feed is controllable by the controller, and an oxidant feed in communication with the test subject fuel cell, the oxidant feed having a temperature, a humidity, a flow rate and a pressure, wherein at least one of the temperature, the humidity, the flow rate and the pressure of the oxidant feed is controllable by the controller, wherein the controller monitors the performance of the test subject fuel cell in response to the fuel feed and the oxidant feed.
In another aspect, the disclosed fuel cell test system may include a housing defining an insulated test chamber and an opening extending into the test chamber, the test chamber being accessible by way of a chamber door connected to the housing, the opening being filled with a removable filler material, a controller received within the housing, a test subject fuel cell positioned in the test chamber, the test subject fuel cell being in communication with the controller to provide the controller with signals indicative of at least one of a voltage and an electric current generated by the test subject fuel cell, a fuel feed in communication with the test subject fuel cell, the fuel feed having a temperature, a humidity, a flow rate and a pressure, wherein the temperature, the humidity, the flow rate and the pressure of the fuel feed are controllable by the controller, an oxidant feed in communication with the test subject fuel cell, the oxidant feed having a temperature, a humidity, a flow rate and a pressure, wherein the temperature, the humidity, the flow rate and the pressure of the oxidant feed are controllable by the controller, and a user interface connected to the housing, wherein the controller is adapted to display the voltage and/or the electric current generated by the test subject fuel cell in response to the fuel feed and the oxidant feed on the user interface.
Other aspects of the disclosed fuel cell test system will become apparent from the following description, the accompanying drawings and the appended claims.
Referring to
The master controller 14 may be a processor, a computer or the like and may be loaded with or otherwise include an operating system and/or various control algorithms for controlling the system 10. The master controller 14 may be a single unit, as shown in
The test chamber 12 may be an oven-like chamber and may be sized and shaped to receive a test subject fuel cell 48, such as a proton exchange membrane (“PEM”) fuel cell or a solid oxide fuel cell (“SOFC”), and associated components of the system 10 therein. For example, the test chamber 12 may be formed as a three-dimensional rectilinear volume, though those skilled in the art will appreciate that the test chamber 12 may have various shapes and geometries. The walls of the test chamber 12 may be generally rigid and may be formed from, lined with or otherwise include insulating materials. In one aspect, the insulating material that lines the test chamber 12 electrically and thermally isolates the test chamber to protect operators from voltage, current and thermal burns. In another aspect, the walls of the test chamber 12 may be lined with a generally white material to assist with vision inside the test chamber 12. Non-limiting examples of suitable insulating materials include melamine foam sheet insulation, fiberglass sheet insulation and the like.
Referring to
In one aspect, the test chamber 12 may include a safety feature adapted to facilitate the safe release of high pressure gases from the test chamber 12 in the event of an ignition or explosion within the test chamber 12. Referring to
The location of the openings 60, 67 may be selected to directed high pressure gases away from personnel and equipment. Therefore, the location of the openings 60, 67 may be dictated by the site where the system 10 will be used. For example, the openings 60, 67 may be positioned in the rear of the housing 50, as shown in
For example, the annular opening 60 shown in
The housing 50 may be formed as a generally compact, bench-top unit or as a stand-alone unit. In one aspect, the housing 50 may be mounted on a 360° swivel base 68 to facilitate positioning, accessing and manipulating the test chamber 12, the user interface 16 and all sides of the housing 50. A shelf may be formed in or connected to the housing and provided beneath the test chamber 12 to provide additional work space for assembling and/or disassembling the test subject fuel cell.
As shown in
Referring to
Referring to
In one aspect, the fuel feed humidity controller 24 may introduce humidity to the fuel and selectively combine humidified fuel with generally dry fuel to achieve the desired fuel humidity in the fuel feed line 70. Humidity may be introduced to the fuel using a traditional water bubble system or by passing the fuel through an ion exchange membrane tube (e.g., a NAFION® tube) submersed in water. Those skilled in the art will appreciate that the humidity sensor 40 may be positioned on the fuel feed line 70 to monitor the humidity of the fuel just before it passes to the test subject fuel cell 48. Uniquely, the system 10 may measure the humidity of the fuel feed inside the test chamber 12 where the humidification measurement is at the same temperature and within intimate proximity to the test subject fuel cell 48. The oxidant feed pressure controller 30 may control the pressure of the oxidant in the oxidant feed line 72. The oxidant feed controller 28 may monitor and control the flow rate of oxidant being supplied from the oxidant supply 26 to the test subject fuel cell 48 by way of the oxidant feed line 72. For example, the oxidant feed flow controller 28 may be a controllable mass flow controller. The oxidant feed humidity controller 32 may be controlled in response to humidity signals received from the humidity sensor 42. The oxidant feed temperature controller 33 may control the temperature of the humidified oxidant in the oxidant feed line 72 between the oxidant feed humidity controller 32 and the test chamber 12. For example, the oxidant feed temperature controller 33 may be a heating jacket received over the oxidant feed line 72.
In one aspect, the oxidant feed humidity controller 32 may introduce humidity to the oxidant and selectively combine humidified oxidant with generally dry oxidant to achieve the desired oxidant humidity in the oxidant feed line 72. Humidity may be introduced to the oxidant using a traditional water bubble system or by passing the oxidant through an ion exchange membrane tube (e.g., a NAFION® tube) submersed in water. Those skilled in the art will appreciate that humidity sensor 42 may be positioned on the oxidant feed line 72 to monitor the humidity of the oxidant just before it passes to the test subject fuel cell 48. Uniquely, the system 10 may measure the humidity of the oxidant feed inside the test chamber 12 where the humidification measurement is at the same temperature and within intimate proximity to the test subject fuel cell 48.
The test subject fuel cell 48 may be connected to a test load when it is positioned in the test chamber 12. Those skilled in the art will appreciate that the test load may be anything that completes the electric circuit between the anode and the cathode of the test subject fuel cell 48. For example, the test load may be an electronically variable resistor capable of drawing the desired target current from the test subject fuel cell 48 by setting an appropriate resistance. In one aspect, as shown in
Furthermore, the fuel feed line 70 and the oxidant feed line 72 may be connected to the appropriate inputs of the test subject fuel cell 48 and a fuel exit line 74 and an oxidant exit line 76 may be connected to the appropriate outputs of the test subject fuel cell 48. In one aspect, one or more of the lines 70, 72, 74, 76 may be connected to the test subject fuel cell 48 using various quick connect couplings (not shown). For example, the quick connect couplings may be quick connect keyed fittings.
The temperature of the test subject fuel cell 48 may be monitored by the first temperature sensor 36 and the ambient temperature of the test chamber 12 may be monitored by the second temperature sensor 38. Temperature sensors 36, 38 may be thermal couples or any other devices capable of communicating a signal indicative of temperature to the master controller 14.
The temperature within the test chamber 12 may be controlled by the heater 34. The heater 34 may be any device capable of supplying heat to the test chamber 12 and may be positioned within the test chamber 12 (e.g., along the walls of the test chamber 12) or may be external of the test chamber 12 and adapted to supply heat to the test chamber 12. For example, the heater 34 may be one or more silicon rubber resistance heaters positioned in the test chamber 12. Those skilled in the art will appreciate that additional heating devices, such as standard cartridge heaters, may be used to provide additional heat to the test chamber 12 and/or directly to the test subject fuel cell 48.
Thus, a user may set a target operating temperature for the test subject fuel cell 48 by manipulating the user interface 16 such that the master controller 14 controls the temperature of the test subject fuel cell 48 (temperature sensor 36) by controlling the heaters 34, 98, 99 and temperature controllers 25, 33, thereby maintaining the desired target temperature (temperature sensors 36, 38) of the test subject fuel cell 48 and its ambient surroundings including the humidity sensors 40, 42 and the fuel and oxidant feed lines 70, 72. Those skilled in the art will appreciate that the target operating temperature, like the target operating pressure, flow rate and humidity, may depend on the type of fuel cell being tested (e.g., SOFC v. PEM) by the system 10.
Accordingly, the master controller 14 may monitor the performance (e.g., generated voltage and/or current) of the test subject fuel cell 48 by way of communication lines 80, 82, which may connect the anode and cathode of the test subject fuel cell 48 to the master controller 14. For example, the performance of the test subject fuel cell 48 may be monitored using electrochemical impedance spectroscopy (“EIS”). The performance of the test subject fuel cell 48, whether in real-time or over time, may be displayed on the user interface 16.
At this point, those skilled in the art will appreciate that the disclosed fuel cell test system 10 may be assembled as a compact, table-top unit capable of providing uniform heating across the test subject fuel cell 48 and the associated feed lines 70, 72, thereby providing more stable fuel cell performance data, while reducing or eliminating the problems associated with condensate formation in the feed lines 70, 72. Additional advantages of the disclosed system 10 may include ultra-fast hydrogen leak detection by way of the flammable gas sensors 44, 46, intrinsically safe operation, burn protection for personnel and materials, electrical protection for personnel and equipment, precise gas leak detection and rapid detection of gas concentrations exceeding hazardous levels, protection of the unit under test from shorting or burning, a small footprint with integrated test chamber and quick connect terminals for gas and electrical connections.
Although various aspects of the disclosed fuel cell test system have been shown and described, modifications may occur to those skilled in the art upon reading the specification.
The present patent application claims priority from U.S. Ser. No. 60/927,988 filed on May 7, 2007, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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60927988 | May 2007 | US |