CN104111425A - Fuel cell cold starting partition performance test system and test method - Google Patents

Abstract

The invention relates to a fuel cell cold start zone performance test system and test method, the test system includes a fuel cell, an oxidant supply unit, a fuel supply unit, a clamping unit, a humidification unit, a cooling pipe, a high and low temperature box, and a zone test board , a load unit, a data acquisition unit and a data processing unit; the test method is: the partition test board replaces the anode plate of the fuel cell; the temperature in the high and low temperature box reaches the set low temperature ambient temperature; the fuel cell is provided with oxidant and fuel , to make it work normally; the data acquisition unit collects the voltage drop across each embedded resistor, the voltage of each temperature resistor and the current flowing through the temperature resistor in real time; the data processing unit calculates the current density of each partition inside the fuel cell according to the received signal The distribution and the temperature of each zone at each moment are obtained to obtain the current density distribution map and the temperature distribution map. Compared with the prior art, the invention has the advantages of convenient operation, visual measurement, high stability and the like.

Description

A fuel cell cold start zone performance test system and test method

technical field

The invention relates to the field of fuel cells, in particular to a fuel cell cold start zone performance test system and a test method.

Background technique

With the shortage of traditional energy sources such as fossils and the continuous warming of the global climate, human beings are facing a huge energy crisis and survival crisis. It is urgent to seek new, efficient and clean energy to gradually replace traditional energy to deal with the energy crisis. Due to its excellent performance, fuel cells have become a research hotspot in various countries in the world, and have played a huge role in power generation, mobile power supply, and vehicle power supply. The research on fuel cell vehicles is getting deeper and deeper, but there are still technical bottlenecks in its commercialization. In addition to battery durability and cost factors, improving low-temperature start-up performance is also one of the key issues.

When the local temperature inside the fuel cell is below freezing point, the water produced by the fuel cell will freeze. Before the temperature in the battery rises to zero, if the water in the catalytic layer freezes, the electrochemical reaction will be stopped due to the ice seal in the local reaction area, and the formation of ice may affect the structure of the membrane electrode assembly due to volume expansion. Serious damage. Among them, the temperature distribution mainly affects the heat distribution inside the fuel cell and the freezing of water, and the current density distribution mainly affects the water generation rate and water distribution. Therefore, building a fuel cell cold start zone test platform, measuring the current density distribution and temperature distribution of the fuel cell cold start zone, and exploring the performance of the fuel cell cold start zone under different conditions are key to improving the performance and life of the proton exchange membrane fuel cell. effect.

Currently published patents and papers do not have any content on the performance test of the fuel cell cold start zone, and most of them only focus on the test of the overall performance of the fuel cell cold start. Therefore, the establishment of a fuel cell cold start partition performance test system is useful for investigating the change law of internal mass transfer and local electrochemical reaction coupling under fuel cell cold start, investigating the internal water and heat distribution characteristics of fuel cells, and optimizing the hydrothermal operating conditions of fuel cells. etc. research has great guiding significance.

Contents of the invention

The object of the present invention is to provide a fuel cell cold start zone performance test system and test method in order to overcome the above-mentioned defects in the prior art, which is used to test the current density and temperature of each fuel cell zone during cold start, and has the advantages of convenient operation, It can realize the advantages of visual measurement and high stability.

The purpose of the present invention can be achieved through the following technical solutions:

A fuel cell cold start partition performance test system, the fuel cell includes an anode plate, a membrane electrode and a cathode plate connected in sequence, the test system includes a fuel cell, an oxidant supply unit, a fuel supply unit, a clamping unit, Humidification unit, cooling pipe, high and low temperature box, partition test board, load unit, data acquisition unit and data processing unit. The partition test board replaces the anode plate and is connected to the membrane electrode of the fuel cell during the test, and is connected through the clamping unit Clamping, the cooling tube is connected to the cathode plate of the fuel cell, the fuel cell, the partition test board, the clamping unit and the cooling pipe are all arranged in the high and low temperature box, the partition test board, the data acquisition unit The data processing unit is connected sequentially, the oxidant supply unit and the fuel supply unit are respectively connected to the humidification unit, the humidification unit is connected to the cooling pipe, and the load unit is connected to the fuel cell.

The high and low temperature box is used to simulate the cold start environment of the fuel cell.

The partition test board includes an upper board and a lower board, the surface of the upper board is engraved with flow channels for replacing anodes, the upper board is divided into several partitions insulated from each other, and the partitions and the lower board are provided with There are embedded resistors, the embedded resistors are respectively connected to the partition and the lower board through the metal pillars, the metal pillars are connected to the data acquisition unit through the sampling line, and a plurality of temperature resistors connected in series are arranged under the upper board, The temperature resistance is connected with the data acquisition unit.

The number of embedded resistors, the number of temperature resistors and the number of partitions are the same.

Both ends of the upper board are provided with interfaces for connecting the data acquisition unit.

The partition test board is provided with round holes for clamping and positioning.

The clamping unit includes a baffle and a top cylinder, the top cylinder is fixed inside the baffle, and the clamping of the partition test board is realized by controlling the expansion and contraction of the top cylinder.

A fuel cell cold start partition performance test method, comprising the following steps:

1) The partition test plate replaces the anode plate of the fuel cell, and is fixed on the fuel cell by a clamping unit;

2) Set the low temperature ambient temperature of the high and low temperature box, and make the temperature in the high and low temperature box reach the set low temperature ambient temperature;

3) The oxidant supply unit and the fuel supply unit respectively provide oxidant and fuel to the fuel cell in the high and low temperature box through the humidification unit and the cooling pipe, and the fuel cell is connected to the load unit and works normally;

4) The data acquisition unit collects the voltage drop across each embedded resistor, the voltage of each temperature resistor, and the current flowing through the temperature resistor in real time, and transmits the collected signal to the data processing unit;

5) The data processing unit calculates the current density distribution of each zone inside the fuel cell and the zone temperature at each time according to the received signal, and outputs and displays the current density distribution map and the temperature distribution map.

The current density distribution of each partition inside the fuel cell is calculated according to the voltage drop across each embedded resistor and the resistance value of the corresponding embedded resistor.

The calculation method of the partition temperature at each moment is as follows:

First, calculate the resistance value of each temperature resistor at this temperature point according to the voltage of each temperature resistor at this moment and the current flowing through the temperature resistor, and then calculate the partition temperature at this moment by the resistance temperature rise formula.

Compared with the prior art, the present invention has the following advantages:

1) The present invention uses a partition test board to measure the current density and temperature distribution of each partition inside the fuel cell during cold start, and realizes the visual measurement of the current density and temperature distribution of the fuel cell at the same time, and is easy to operate.

2) The present invention uses means such as high and low temperature boxes and cooling pipes to simulate the cold start of the fuel cell at low temperatures without being restricted by the external environment.

3) The present invention realizes the automatic clamping of the fuel cell by controlling the clamping unit, and at the same time, the clamping pressure is uniform and the operation is convenient.

Description of drawings

Fig. 1 is the circuit schematic diagram of test system of the present invention;

Figure 2 is a structural diagram of the partition test board;

Fig. 3 is a sectional view of the partition test board;

Fig. 4 is the flowchart of testing method of the present invention;

Fig. 5 is a schematic diagram of fuel and oxidant cooling in the present invention.

In the figure: 1. Fuel cell; 2. Partition test board; 3. Clamping unit; 4. Cooling pipe; 5. High and low temperature box; 6. Oxidant supply unit; 7. Fuel supply unit; 8. Humidification unit; 9. Data acquisition unit; 10. Data processing unit; 11. Load unit; 12. Membrane electrode; 13. Cathode plate; 14. Exhaust pipe, A. Unreacted fuel and oxidant; 21. Interface; 22. Reaction area; 23. Flow channel; 24, round hole; 25, temperature resistance; 26, metal column; 27, sampling line; 28, embedded resistance.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is carried out on the premise of the technical solution of the present invention, and detailed implementation and specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

As shown in Figure 1, a fuel cell cold start zone performance test system, the test system includes a fuel cell 1, an oxidant supply unit 6, a fuel supply unit 7, a clamping unit 3, a humidification unit 8, a cooling pipe 4, High and low temperature box 5, partition test board 2, load unit 11, data acquisition unit 9 and data processing unit 10, described fuel cell includes sequentially connected anode plate, membrane electrode 12 and cathode plate 13, described partition test board 2 During the test, the anode plate is replaced with the membrane electrode 12 of the fuel cell 1 and clamped by the clamping unit 3. The cooling tube 4 is connected with the cathode plate 13 of the fuel cell 1. The fuel cell 1, partition The test board 2, the clamping unit 3 and the cooling pipe 4 are all arranged in the high and low temperature box 5, the partition test board 2, the data acquisition unit 9, and the data processing unit 10 are connected in sequence, and the oxidant supply unit 6, fuel The supply unit 7 is respectively connected to the humidification unit 8 , the humidification unit 8 is connected to the cooling pipe 4 , and the load unit 11 is connected to the fuel cell 1 . There are two humidifying units 8 and two cooling pipes 4, which are respectively connected correspondingly. The test system can simulate the cold start condition of the fuel cell at low temperature, measure the performance parameters of the fuel cell partition during the cold start, the operation is simple, and at the same time realize the visual measurement of the fuel cell current density and temperature distribution. An exhaust pipe 14 for exhausting unreacted fuel and oxidant A is connected to the fuel cell 1 .

The high and low temperature box 5 is used to simulate the cold start environment of the fuel cell, and the fuel cell is put into the high and low temperature box for testing.

As shown in Figures 2-3, the partition test board 2 includes an upper plate and a lower plate, the reaction area 22 on the upper surface of the upper plate and the lower surface of the lower plate are in contact with the membrane electrode, and the other parts are made of insulating materials. . The reaction area 22 on the surface of the upper plate is engraved with a flow channel 23 for replacing the anode, and the upper plate is divided into several mutually insulated partitions so that the current between the partitions will not flow laterally. Embedded resistors 28 are arranged between the boards, and the embedded resistors 28 are respectively connected to the partition and the lower board through the metal pillars 26. The metal pillars 26 are connected to the data acquisition unit 9 through the sampling lines 27. A plurality of temperature resistors 25 connected in series are provided, the temperature resistors 25 are connected to the data acquisition unit 9, and the temperature resistors are not connected to the upper and lower boards. The number of embedded resistors, the number of temperature resistors and the number of partitions are the same, all of which are n.

Both ends of the upper board are provided with interfaces 21 for connecting to the data acquisition unit 9 . The partition test board 2 is provided with two circular holes 24 for clamping and positioning.

The clamping unit 3 includes a baffle and a top cylinder, the top cylinder is fixed inside the baffle, and the clamping of the partition test board is realized by controlling the expansion and contraction of the top cylinder.

As shown in Figure 4, a fuel cell cold start partition performance test method includes the following steps:

1) The partition test board 2 replaces the anode plate of the fuel cell 1, and is fixed on the fuel cell 1 through the clamping unit 3;

2) setting the low temperature environment temperature of the high and low temperature box 5, and making the temperature in the high and low temperature box 5 reach the set low temperature environment temperature;

3) The oxidant supply unit 6 and the fuel supply unit 7 provide oxidant and fuel to the fuel cell 1 in the high and low temperature box 5 through the humidification unit 8 and the cooling pipe 4 respectively, and the fuel cell 1 is connected to the load unit 11 and works normally;

4) The data acquisition unit 9 collects the voltage drop across each embedded resistor, the voltage of each temperature resistor, and the current flowing through the temperature resistor in real time, and transmits the collected signal to the data processing unit 10;

5) The data processing unit 10 calculates the current density distribution of each zone inside the fuel cell and the zone temperature at each time according to the received signal, and outputs and displays the current density distribution map and the temperature distribution map.

The current density distribution of each partition inside the fuel cell is calculated according to the voltage drop across each embedded resistor and the resistance value of the corresponding embedded resistor.

The calculation method of the partition temperature at each moment is as follows: when the fuel cell is working, the data acquisition unit supplies power to the power supply arranged therein for the temperature resistance, and since the temperature resistance rises with the temperature rise, each temperature is collected by the data acquisition unit The resistance value of each temperature resistance at the temperature point is calculated by the resistance voltage and the current flowing through the temperature resistance, and then the partition temperature at this moment is calculated by the resistance temperature rise formula.

Fig. 5 is a schematic diagram of fuel and oxidant cooling in the present invention. The serpentine cooling tube is placed in the high and low temperature box, the fuel and oxidant intake temperature T1, after passing through the cooling tube, the temperature drops to _T2 , which is the same as the internal temperature of the high and low temperature box, simulating the fuel cell intake in a low temperature environment. For a 25cm ² cell, the maximum gas flow rate is 3L/min, the mass flow rate is about 3g/min, and the heat Q ₁ is brought by the air:

Q ₁ =c×m _g ×AT=c×m _g ×(T ₁ -T ₂ )

Oxidant cooling pipe inner diameter fuel pipe inner diameter The aluminum alloy material used for the cooling pipe has a thermal conductivity of 162W/(m*K). Since the outside of the cooling pipe is forced convection, the thermal conductivity of 20-100W/(m*K) is not easy to determine, so it is calculated according to the minimum thermal conductivity and heat transfer The process calculation (Q2=Q1) shows that the approximate length of the oxidant cooling pipe is 1.0416m, and the approximate length of the fuel cooling pipe is 1.38mm. For the sake of safety, the actual length of the oxidant cooling pipe is 2.3m, and the length of the fuel cooling pipe is 3.6m, which meet the calculation heat transfer requirements. The fluid heat transfer formula used is:

${\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; kA\&Delta;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&sigma;</span>}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;r</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span>$

Claims (10)

1. a fuel cell cold start-up subregion Performance Test System, described fuel cell comprises the positive plate connecting successively, membrane electrode and minus plate, it is characterized in that, described test macro comprises fuel cell, oxygenant feed unit, fuel supply unit, clamping unit, humidifying unit, cooling tube, high-low temperature chamber, subregion test board, load unit, data acquisition unit and data processing unit, described subregion test board substitutes positive plate and is connected with the membrane electrode of fuel cell in the time of test, and clamp by clamping unit, described cooling tube is connected with the minus plate of fuel cell, described fuel cell, subregion test board, clamping unit and cooling tube are all arranged in high-low temperature chamber, described subregion test board, data acquisition unit, data processing unit connects successively, described oxygenant feed unit, fuel supply unit connects respectively humidifying unit, described humidifying unit is connected with cooling tube, described load unit is connected with fuel cell.

2. a kind of fuel cell cold start-up subregion Performance Test System according to claim 1, is characterized in that, described high-low temperature chamber is for analog fuel battery cold start-up environment.

3. a kind of fuel cell cold start-up subregion Performance Test System according to claim 1, it is characterized in that, described subregion test board comprises upper plate and lower plate, described upper panel surface is carved with the runner for substituting anode, upper plate is split into the subregion of several mutually insulateds, between described each subregion and lower plate, be provided with embedding resistance, described embedding resistance connects respectively subregion and lower plate by metal column, described metal column is connected with data acquisition unit by sample line, described upper plate below is provided with the temperature and resistance of multiple series connection, described temperature and resistance is connected with data acquisition unit.

4. a kind of fuel cell cold start-up subregion Performance Test System according to claim 3, is characterized in that, described embedding resistance number, temperature and resistance number and subregion number are identical.

5. a kind of fuel cell cold start-up subregion Performance Test System according to claim 3, is characterized in that, described upper plate two ends are provided with the interface for connection data collecting unit.

6. a kind of fuel cell cold start-up subregion Performance Test System according to claim 1, is characterized in that, described subregion test board is provided with the circular hole for clamping location.

7. a kind of fuel cell cold start-up subregion Performance Test System according to claim 1, is characterized in that, described clamping unit comprises baffle plate and takes blame for others, takes blame for others and be fixed on baffle interior, the flexible clamping of realizing subregion test board of taking blame for others by control.

8. a fuel cell cold start-up subregion performance test methods as claimed in claim 3, is characterized in that, comprises the following steps:

1) positive plate of subregion test board alternative fuel battery, and be fixed on fuel cell by clamping unit;

2) set the low temperature environment temperature of high-low temperature chamber, and make temperature in high-low temperature chamber reach the low temperature environment temperature of setting;

3) oxygenant feed unit, fuel supply unit provide oxygenant and fuel by humidifying unit and cooling tube to the fuel cell in high-low temperature chamber respectively, and fuel cell connects load unit, normally works;

4) voltage of the two ends pressure drop of the each embedding resistance of data acquisition unit Real-time Collection, each temperature and resistance and flow through the electric current of temperature and resistance, and the signal of collection is transferred to data processing unit;

5) data processing unit is according to the electric current distribution of the each subregion of calculated signals fuel battery inside and the subregion temperature in each moment that receive, exports and shows current density distributing figure and temperature profile.

9. a kind of fuel cell cold start-up subregion performance test methods according to claim 8, is characterized in that, the electric current distribution of the described each subregion of fuel battery inside obtains according to the computing the resistor value of the two ends pressure drop of each embedding resistance and corresponding embedding resistance.

10. a kind of fuel cell cold start-up subregion performance test methods according to claim 8, is characterized in that, the computing method of the subregion temperature in described each moment are:

First the galvanometer of inscribing each temperature and resistance voltage during according to this and flow through temperature and resistance calculates the resistance of each temperature and resistance under this temperature spot, then obtains the subregion temperature in this moment by resistance temperature rise formula.