CN108123153A - A kind of proton type solid oxide fuel cell and preparation method thereof - Google Patents

Abstract

The invention relates to a proton-type solid oxide fuel cell, which is composed of a composite anode layer, a dense proton-conducting electrolyte layer, a porous proton-conducting electrolyte layer and a cathode layer. The dense proton-conducting electrolyte layer can effectively block the cathode gas and the anode gas, and the porous proton-conducting electrolyte layer can effectively improve the contact between the electrolyte and the cathode, and improve the electrochemical performance of the high-temperature proton-type solid oxide fuel cell.

Description

A kind of proton type solid oxide fuel cell and its preparation method

technical field

The invention belongs to the field of fuel cells, in particular to a proton type solid oxide fuel cell.

Background technique

Proton-type solid oxide fuel cells use protons with low conduction activation energy as carriers, which has great potential in reducing the operating temperature of solid oxide fuel cells. However, the preparation process of the high-temperature proton membrane is complicated, and the matching and stability of the cathode material have restricted the application of the proton-type solid oxide fuel cell. Commonly used proton-conducting oxide membrane materials such as BCY and BZY have the characteristics of refractory. Common proton-conducting solid oxide cathode materials include BSCF, BSC, etc., which often have poor thermal matching with the electrolyte and react at high temperatures to form a non-conductive layer. Reduce battery performance. Studies have shown that adding a separator between the electrolyte and the cathode, that is, a certain proportion of the cathode and the electrolyte mixed slurry, can improve the performance of the overall battery, but it is necessary to coat the surface with a layer of cathode current collector, which makes the preparation process more complicated and the cost is higher. High (Solid State Ionics, 2012, 214(214): 1‐5.). In addition, by adjusting the ratio and type of elements in the cathode, improving the matching of the cathode on the electrolyte membrane and reducing the reaction between the two, the performance of the cathode can also be improved, but the above method has disadvantages such as high cost and complicated operation. Therefore, designing a proton-type solid oxide fuel cell, improving the contact between the cathode and the proton-conducting electrolyte, and reducing the battery contact resistance can improve the electrochemical performance of the proton-type solid oxide fuel cell.

Contents of the invention

In order to overcome the problem of poor contact between the electrolyte and the cathode of the proton-type solid oxide fuel cell, the present invention proposes a proton-type solid oxide fuel cell, which is characterized in that the solid oxide fuel cell is composed of a composite anode layer, dense proton conduction BZY electrolyte layer, porous proton conduction BZY electrolyte layer and cathode layer, the preparation process of the solid oxide fuel cell is as follows,

(1) After mixing NiO and BZY, add an organic solvent, and sinter at high temperature to form an anode layer ceramic green body;

(2) YSZ powder is mixed with an organic solvent to prepare YSZ slurry, and the YSZ slurry is coated on the anode layer ceramic green body, and after sintering at high temperature, a dense YSZ film is obtained;

(3) After mixing the barium-containing compound and YSZ in proportion, add an organic solvent, and perform ultrasonic treatment to obtain a barium-containing slurry;

(4) Apply the barium-containing slurry on the surface of the YSZ film. After high-temperature sintering, the barium-containing slurry undergoes melting, decomposition, migration and diffusion of barium elements into the YSZ lattice, and finally forms dense protons closely connected with the composite anode layer. A conductive BZY electrolyte layer, and a porous proton-conductive BZY electrolyte layer closely connected with a dense proton-conductive BZY electrolyte layer;

(5) Prepare a cathode layer on the porous proton-conducting BZY electrolyte layer to obtain the proton-type solid oxide fuel cell.

The solid oxide fuel cell is composed of a composite anode layer, a dense proton-conducting BZY electrolyte layer, a porous proton-conducting BZY electrolyte layer and a cathode layer stacked in sequence.

The thickness of the composite anode layer is 300-1000 microns, the thickness of the dense proton-conducting BZY electrolyte layer is 3-20 microns, the thickness of the porous proton-conducting BZY electrolyte layer is 10-50 microns, and the thickness of the cathode layer is 20-50 microns.

The weight ratio of NiO to BZY in the composite anode layer is between 30/70 and 80/20.

The cathode layer is a perovskite oxide cathode or a composite cathode composed of a perovskite oxide and a proton-conducting oxide; the proton-conducting oxide is one or more of BZY, BCY, BZCY, and BZYYb. The mass content of the cathode is 0‐0.9; the molar composition of YSZ is yttrium to zirconium molar ratio 2:8.

In the proton-type solid oxide fuel cell, the weight ratio of NiO to BZY is between 30/70 and 80/20. After NiO and BZY are mixed, they are sintered at a high temperature of 900°C to 1200°C to form an anode layer ceramic green body. The anode layer ceramic green body is coated with YSZ slurry, and after sintering at a high temperature of 1250 ° C to 1500 ° C, a dense YSZ film is obtained.

The preparation method of the proton-type solid oxide fuel cell, mixing barium-containing compounds such as barium oxide, barium carbonate, and barium nitrate with YSZ, the molar ratio of barium to YSZ is 0.6-1.0, ultrasonic Treat for 20h to 168h to obtain barium-containing slurry.

The preparation method of the proton-type solid oxide fuel cell is to apply the barium-containing slurry on the surface of the YSZ film and bake it at 1000-1300°C for 10h-60h. In the YSZ lattice, a dense proton-conducting BZY electrolyte layer closely connected to the composite anode layer, and a porous proton-conducting BZY electrolyte layer closely connected to the dense proton-conducting BZY electrolyte layer are finally formed.

In the preparation method of the proton type solid oxide fuel cell, a cathode layer is prepared on the porous proton-conducting BZY electrolyte layer by one of the slurry coating method, the screen printing method or the dipping method.

The organic solvent is one or more of fish oil, PVB glue, terpineol and n-butanol, wherein ethyl cellulose is not added or can also be added, and its addition amount in the solvent is 30% of the mass of the barium-containing compound. %‐50%.

The beneficial effects of the present invention are: the problem of poor contact between the electrolyte and the cathode of the proton-type solid oxide fuel cell is solved, and the proton-type solid oxide fuel cell consists of a composite anode layer, a dense proton-conducting electrolyte layer, a porous proton-conducting electrolyte layer and The composition of the cathode layer. The dense proton-conducting electrolyte layer can effectively block the cathode gas and the anode gas, and the porous proton-conducting electrolyte layer can effectively improve the contact between the electrolyte and the cathode, and improve the electrochemical performance of the high-temperature proton-type solid oxide fuel cell.

Detailed ways

Example 1

NiO and YSZ were ball milled for 24 hours according to the mass ratio of 40:60, mixed uniformly, tape casted, and sintered at 1000°C for 5 hours to obtain a 400 micron thick anode green body. The YSZ slurry was drip-coated on the anode ceramic green body, dried for 6 hours and then sintered at 1300° C. for 8 hours to obtain a 20-micron YSZ film with a density of 97.2%. Mix BaO and YSZ at a molar ratio of 0.6:1.0, and add terpineol and n-butanol containing 6% ethyl cellulose at a mass ratio of 0.3:1:1 to the mixed powder, stir evenly and ultrasonicate for 42 hours. The BZY slurry was drip-coated on the surface of the dense YSZ membrane, dried at room temperature for 4 hours, and then sintered at 1320°C for 20 hours to obtain a 20-micron BZY film with a density of 96.2%, a porosity of 56%, and a pore size of 0.2-2 microns. A porous BZY layer with a thickness of 40 microns is impregnated with a BSCF solution into the porous BZY layer, and sintered to obtain a BSCF-BZY/BZY/YSZ-NiO proton-type solid oxide battery. The working conditions for testing battery performance are: _H2 containing 10% _H2O is the fuel gas, the flow rate is 120mL/min; _O2 is the oxidant, the flow rate is 100mL/min, the open circuit voltage is 1.2955V at 500°C, and the power can reach 328mW /cm ² .

Example 2

NiO and YSZ were ball milled for 24 hours according to the mass ratio of 50:50, mixed evenly, tape casted, and sintered at 950°C for 5 hours to obtain a 500 micron anode green body. The YSZ slurry was hang-coated on the anode ceramic green body, dried for 6 hours and then sintered at 1350° C. for 8 hours to obtain a 5-micron YSZ film with a density of 99.2%. Mix BaCO ₃ and YSZ at a molar ratio of 0.8:1.0, and fish oil, n-butanol, PVB glue, and mixed powder at a mass ratio of 0.05:2:1:1, stir evenly and ultrasonicate for 64 hours. The BZY slurry was suspended-coated on the surface of the dense YSZ membrane, dried at room temperature for 3 hours, and then sintered at 1400°C for 40 hours to obtain a 5-micron dense BZY film with a density of 98.4%, a porosity of 48%, and a pore size of 0.3-2 microns , a porous BZY layer with a thickness of 20 microns, impregnating the LSF impregnating solution in the BZY porous layer, and obtaining the LSF-BZY/BZY/YSZ-NiO proton-type solid oxide battery after calcination. The working conditions for testing battery performance are: _H2 containing 10% _H2O is the fuel gas, the flow rate is 120mL/min; _O2 is the oxidant, the flow rate is 100mL/min, the open circuit voltage is 1.3155V at 500°C, and the power can reach 312mW /cm ² .

Example 3

NiO and YSZ were ball milled for 24 hours according to the mass ratio of 60:40, mixed uniformly, tape casted, and sintered at 1100°C for 5 hours to obtain a 300 micron anode green body. The YSZ slurry was drip-coated on the anode ceramic green body, dried for 6 hours and then sintered at 1400° C. for 8 hours to obtain a 10-micron YSZ film with a density of 98.5%. Ba(NO ₃ ) ₂ and YSZ were mixed at a molar ratio of 1.0:1.0, and terpineol containing 6% ethyl cellulose was added at a mass ratio of 0.3:1 to the mixed powder, stirred evenly and ultrasonicated for 168 hours. The BZY slurry was drop-coated on the surface of the dense YSZ membrane, dried at room temperature for 4 hours, and then sintered at 1450°C for 50 hours to obtain a 10-micron dense BZY film with a density of 97.4%, a porosity of 53%, and a pore size of 0.1-5 microns , a porous BZY layer with a thickness of 30 microns, impregnating the LSCF impregnating solution in the BZY porous layer, and obtaining the LSCF-BZY/BZY/YSZ-NiO proton-type solid oxide battery after calcination. The working conditions for testing battery performance are: _H2 containing 10% _H2O is the fuel gas, the flow rate is 120mL/min; _O2 is the oxidant, the flow rate is 100mL/min, the open circuit voltage is 1.2763V at 550°C, and the power can reach 358mW /cm ² .

Claims (10)

1. a kind of proton type solid oxide fuel cell, it is characterised in that：The solid oxide fuel cell is by compound sun Pole layer, fine and close proton conduct BZY electrolyte layers, and porous proton conduction BZY electrolyte layers and cathode layer stack gradually composition.

2. proton type solid oxide fuel cell as described in claim 1, it is characterised in that：Composite anode layer thickness 300 Micron~1000 microns, fine and close 3 microns~20 microns of proton conduction BZY electrolyte layers thickness, porous proton conducts BZY electrolyte 10 microns~50 microns of layer thickness, 20 microns~50 microns of cathode electrode layer thickness.

3. proton type solid oxide fuel cell as claimed in claim 1 or 2, it is characterised in that：NiO in composite anode layer Weight ratio with BZY is between 30/70~80/20.

4. proton type solid oxide fuel cell as claimed in claim 1 or 2, it is characterised in that：

Cathode layer is perovskite oxide cathode or the composite cathode of perovskite oxide and proton conductive oxide composition；Proton Conductive oxide be BZY, BCY, BZCY, BZYYb in one or two or more kinds, in cathode mass content be 0-90%； YSZ is 8%molY₂O₃Stable ZrO₂。

5. the preparation method of the proton type solid oxide fuel cell as described in claim 1-4 is any, process is as follows,

(1) after NiO is mixed with BZY, organic solvent is added in, sintering at high temperature forms anode layer biscuit of ceramics；

(2) YSZ slurries are configured to after YSZ powders are mixed with organic solvent, YSZ slurries are applied on anode layer biscuit of ceramics, After being sintered at high temperature, fine and close YSZ films are obtained；

(3) after containing barium compound is mixed in proportion with YSZ, organic solvent is added, is ultrasonically treated, obtains baric slurry；

(4) by baric slurry coating after YSZ film surfaces, high temperature sintering, baric slurry is moved by melting, decomposition, barium element Move, diffuse into YSZ lattices, ultimately form fine and close proton conduction BZY electrolyte layers close-connected with composite anode layer and With the close-connected porous proton conduction BZY electrolyte layers of fine and close proton conduction BZY electrolyte layers；

(5) cathode layer is prepared in porous proton conduction BZY electrolyte layers, obtains the proton type solid oxide fuel cell.

6. the preparation method of proton type solid oxide fuel cell as claimed in claim 5, it is characterised in that：NiO and BZY Weight ratio between 30/70~80/20, after NiO is mixed with BZY, at 900 DEG C~1200 DEG C of high temperature sintering form anode layer Biscuit of ceramics applies YSZ slurries on anode layer biscuit of ceramics, after being sintered at 1250 DEG C~1500 DEG C of high temperature, obtains densification YSZ films.

7. the preparation method of proton type solid oxide fuel cell as claimed in claim 5, it is characterised in that：By baric Closing that object such as one or both of barium monoxide, barium carbonate, barium nitrate is above mix with YSZ, barium and YSZ molar ratios be 0.6~ 1.0,20h~168h is ultrasonically treated, obtains baric slurry.

8. the preparation method of proton type solid oxide fuel cell as claimed in claim 5, it is characterised in that：Baric is starched Expect coated in YSZ film surfaces, 10h~60h are roasted at 1000~1300 DEG C, and baric slurry is moved by melting, decomposition, barium element Move, diffuse into YSZ lattices, ultimately form fine and close proton conduction BZY electrolyte layers close-connected with composite anode layer and With the close-connected porous proton conduction BZY electrolyte layers of fine and close proton conduction BZY electrolyte layers.

9. the preparation method of proton type solid oxide fuel cell as claimed in claim 5, it is characterised in that：Pass through slurry One kind prepares cathode layer in porous proton conduction BZY electrolyte layers in cladding process, silk screen print method or infusion process.

10. the preparation method of proton type solid oxide fuel cell as claimed in claim 5, it is characterised in that：It is described to have Solvent is one or more kinds of in fish oil, PVB glue, terpinol and n-butanol, wherein not adding or can also add ethyl fibre Dimension element, the additive amount in solvent are the 30%-50% of containing barium compound quality.