Perovskite solar cell, battery module and preparation method

Abstract

The present invention discloses a perovskite solar cell, a battery module and a preparation method thereof. The perovskite solar cell of the present invention includes: a first porous carbon electrode layer and a second porous carbon electrode layer, and the second porous carbon electrode layer covers the upper surface of the first porous carbon electrode layer; the first porous carbon electrode layer is formed by a first porous carbon electrode layer slurry containing graphite, and the particle size of graphite in the first porous carbon electrode layer slurry is 0.2 - 30 μm; the second porous carbon electrode layer is formed by a second porous carbon electrode layer slurry containing graphite, and the particle size of graphite in the second porous carbon electrode layer slurry is 0.1 - 10 μm; and the particle size of graphite in the second porous carbon electrode layer slurry is smaller than that of graphite in the first porous carbon electrode layer slurry. The perovskite solar cell of the present invention can effectively solve the problem of warping of the porous carbon electrode layer.

Description

Technical Field

[0001] The present invention relates to a perovskite solar cell and a preparation method thereof, and also relates to a perovskite solar cell module and a preparation method thereof. Background Art

[0002] In recent years, the research on perovskite solar cells has become popular all over the world. Currently, the highest certified cell efficiency by authoritative institutions has exceeded 25%, which is higher than that of traditional thin-film solar cells. Compared with other types of solar cells, perovskite solar cells have the advantages of wide material sources, simple manufacturing processes, and low costs.

[0003] Among various perovskite solar cell technologies, printable mesoscopic perovskite solar cells have the advantages of good stability, low cost, and easy large-scale production due to their unique device structures and characteristics based on screen printing processes. The porous carbon electrode layer is a key component of printable mesoscopic perovskite solar cells. However, the adhesion of commonly used carbon electrodes is weak. When the perovskite precursor solution is drop-coated, the carbon layer is prone to warping, the contact effect becomes weak, and the extraction and transport of charges at the back electrode are affected. Summary of the Invention

[0004] In view of this, on the one hand, the present invention provides a perovskite solar cell, which effectively solves the problem of warping of the porous carbon electrode layer. Further, the present invention reduces the internal resistance of the perovskite solar cell, improves the fill factor and photoelectric conversion efficiency of the perovskite solar cell. On the other hand, the present invention provides a perovskite solar cell module. On yet another hand, the present invention provides a preparation method of a perovskite solar cell. On still another hand, the present invention provides a preparation method of a perovskite solar cell module.

[0005] On the one hand, the present invention provides a perovskite solar cell, specifically a printable mesoscopic perovskite solar cell. The perovskite solar cell of the present invention includes a first porous carbon electrode layer and a second porous carbon electrode layer, and the second porous carbon electrode layer covers the upper surface of the first porous carbon electrode layer;

[0006] The first porous carbon electrode layer is formed by a first porous carbon electrode layer slurry containing graphite, and the particle size of graphite in the first porous carbon electrode layer slurry is 0.2 - 30 μm; the second porous carbon electrode layer is formed by a second porous carbon electrode layer slurry containing graphite, and the particle size of graphite in the second porous carbon electrode layer slurry is 0.1 - 10 μm; and the particle size of graphite in the second porous carbon electrode layer slurry is smaller than that in the first porous carbon electrode layer slurry.

[0007] According to an embodiment of the present invention, the shape of the upper surface of the second porous carbon electrode layer is the same as that of the upper surface of the first porous carbon electrode layer.

[0008] In the present invention, a second porous carbon electrode layer with a smaller graphite particle size is covered on the upper surface of the first porous carbon electrode layer. The pores of the second porous carbon electrode layer are denser, and the interaction force between them is enhanced, improving the adhesion force between the film layers and eliminating the warping phenomenon of the porous carbon electrode layer caused by being wetted by the solution due to weak adhesion force during the process of drop-coating the perovskite precursor solution. In addition, the second porous electrode layer has a lower internal resistance, improving the fill factor of the perovskite solar cell and the efficiency of the perovskite solar cell.

[0009] In the present invention, the particle size of graphite in the first porous carbon electrode layer slurry is preferably 1 - 20 μm; more preferably 5 - 15 μm.

[0010] In the present invention, the particle size of graphite in the second porous carbon electrode layer slurry is preferably 0.3 - 5 μm; more preferably 0.5 - 3 μm. This helps to improve the adhesion force of the porous graphite electrode layer and reduce the internal resistance of the porous graphite electrode layer.

[0011] For the perovskite solar cell according to the present invention, preferably, the first porous carbon electrode layer slurry is formed from raw materials including graphite, carbon black, and zirconia, and the second porous carbon electrode layer slurry is formed from raw materials including graphite, carbon black, and zirconia.

[0012] The mass ratio of graphite, carbon black, and zirconia in the first porous carbon electrode layer slurry of the present invention can be (1 - 6):1:(0.1 - 1), preferably (2 - 4):1:(0.3 - 0.7).

[0013] The mass ratio of graphite, carbon black, and zirconia in the second porous carbon electrode layer slurry of the present invention can be (1 - 6):1:(0.1 - 1), preferably (2 - 4):1:(0.3 - 0.7).

[0014] For the perovskite solar cell according to the present invention, preferably, the mass ratio of graphite, carbon black, and zirconia in the first porous carbon electrode layer slurry is (1 - 6):1:(0.1 - 1), and the mass ratio of graphite, carbon black, and zirconia in the second porous carbon electrode layer slurry is (1 - 6):1:(0.1 - 1).

[0015] For the perovskite solar cell according to the present invention, preferably, the thickness of the second porous carbon electrode layer is 10 - 500 μm.

[0016] In the present invention, the thickness of the first porous carbon electrode layer can be 5 - 100 μm; preferably 10 - 40 μm.

[0017] In the present invention, the thickness of the second porous carbon electrode layer can be 10 - 500 μm; preferably 15 - 100 μm. This helps to eliminate the warping phenomenon of the porous carbon electrode layer.

[0018] The perovskite solar cell of the present invention may further include a porous insulating spacer layer. The first porous carbon electrode layer covers the porous insulating spacer layer.

[0019] According to the perovskite solar cell of the present invention, preferably, the perovskite solar cell further includes a transparent substrate, a conductive layer, a dense layer, a porous electron transport layer, a porous insulating spacer layer, and a perovskite filled in the pores of the porous electron transport layer, the porous insulating spacer layer, the first porous carbon electrode layer, and the second porous carbon electrode layer, which are stacked in sequence from bottom to top;

[0020] The first porous carbon electrode layer covers the porous insulating spacer layer.

[0021] According to the perovskite solar cell of the present invention, preferably, the conductive layer has an insulating band formed by etching lines, thereby dividing the transparent substrate and the conductive layer into a negative electrode region and a positive electrode region;

[0022] The dense layer covers the upper surface of the conductive layer in the negative electrode region;

[0023] The porous electron transport layer covers the upper surface of the dense layer;

[0024] The porous insulating spacer layer covers the entire porous electron transport layer and is filled into the insulating band;

[0025] The first porous carbon electrode layer covers the upper surface of the mesoporous insulating spacer layer and the upper surface of the conductive layer in the positive electrode region;

[0026] The second porous carbon electrode layer covers the upper surface of the first porous carbon electrode layer.

[0027] In the present invention, the transparent substrate can be transparent glass or a transparent polymer. Examples of the transparent polymer include but are not limited to polyvinyl chloride, polymethyl methacrylate, polycarbonate, polystyrene, polyethylene, ethylene - vinyl acetate copolymer. According to an embodiment of the present invention, the transparent substrate is transparent glass.

[0028] In the present invention, the conductive layer can be formed of fluorine - doped tin oxide or indium tin oxide. According to an embodiment of the present invention, the conductive layer is formed of fluorine - doped tin oxide.

[0029] In the present invention, the dense layer can be formed of titanium dioxide.

[0030] In the present invention, the porous electron transport layer has a mesoporous structure. The porous electron transport layer may be formed of titanium dioxide, tin oxide, or barium stannate. According to an embodiment of the present invention, the porous electron transport layer is formed of titanium dioxide.

[0031] In the present invention, the porous insulating spacer layer has a mesoporous structure. The porous insulating spacer layer may be formed of zirconium dioxide, silicon dioxide, or aluminum oxide. According to an embodiment of the present invention, the porous insulating spacer layer is formed of zirconium dioxide.

[0032] For the perovskite solar cell according to the present invention, preferably, the conductive layer is formed of fluorine-doped tin oxide or indium tin oxide; the dense layer is formed of titanium dioxide; the porous electron transport layer is formed of titanium dioxide, tin oxide, or barium stannate; and the insulating spacer layer is formed of zirconium dioxide, silicon dioxide, or aluminum oxide.

[0033] The perovskite of the present invention may be a compound having the following structure:

[0034] ABX3

[0035] Wherein, A is a monovalent cation selected from one or more of methylamine, formamidine, or cesium; B is a divalent cation selected from one or more of lead or tin; and X is a monovalent anion selected from one or more of iodine, bromine, chlorine, or pseudohalogen. Examples of anions formed by pseudohalogen include, but are not limited to, BF4 - , SCN - . According to an embodiment of the present invention, the perovskite is CH3NH3PbI3.

[0036] On the other hand, the present invention provides a perovskite solar cell module, which includes at least two sets of the above perovskite solar cells, and the perovskite solar cells are arranged in series.

[0037] On yet another aspect, the present invention provides a method for preparing a perovskite solar cell, including the following steps:

[0038] (1) Printing a second porous carbon electrode layer slurry on the first porous carbon electrode layer to form a second porous carbon electrode layer;

[0039] (2) Dropping a perovskite precursor solution into the second porous carbon electrode layer, and allowing the perovskite precursor solution to diffuse and infiltrate into the pores of the first porous carbon electrode layer and the second porous carbon electrode layer;

[0040] The second porous carbon electrode layer slurry includes graphite, carbon black, zirconium dioxide, terpineol, and ethyl cellulose.

[0041] The particle size of graphite in the second porous carbon electrode layer slurry can be 0.1 - 10 μm; preferably 0.3 - 5 μm; more preferably 0.5 - 2 μm. The particle size of graphite in the second porous carbon electrode layer is smaller than that in the first porous carbon electrode layer.

[0042] The thickness of the second porous carbon electrode layer can be 10 - 500 μm; preferably 15 - 100 μm; more preferably 20 - 50 μm.

[0043] In the present invention, a screen printing machine can be used to print the second porous carbon electrode layer slurry on the first porous carbon electrode layer. After printing, drying and / or sintering steps can also be carried out. The sintering temperature can be 300 - 600 °C; preferably 400 - 550 °C.

[0044] In the second porous carbon electrode layer slurry of the present invention, based on 1 part by weight of carbon black, the amount of graphite used can be 1 - 6 parts by weight, preferably 2 - 4 parts by weight; the amount of ethyl cellulose used can be 0.1 - 1 part by weight, preferably 0.3 - 0.7 part by weight; the amount of zirconia used can be 0.1 - 1 part by weight, preferably 0.3 - 0.7 part by weight; the amount of terpineol used can be 2 - 5 parts by weight, preferably 3 - 4 parts by weight.

[0045] The preparation method of the second porous carbon electrode layer slurry can include the following steps: forming a mixture A of graphite, carbon black and a solvent; mixing the mixture formed by ethyl cellulose and terpineol with mixture A; evaporating the solvent to obtain the second porous carbon electrode layer slurry. This is beneficial to the dispersion of raw materials, thereby helping to improve the adhesion of the porous carbon electrode layer and reduce the internal resistance.

[0046] The solvent can be an alcohol solvent. Examples of alcohol solvents include but are not limited to one or more of methanol, ethanol, propanol, and isopropanol. According to an embodiment of the present invention, the solvent is anhydrous ethanol.

[0047] Mixture A can be formed in a nano ultrasonic disperser. The frequency of the nano ultrasonic disperser can be 10 - 30 KHz; preferably 15 - 25 KHz. The treatment time can be 70 - 150 min; preferably 90 - 120 min. An intermittent treatment method can be adopted, setting to work for 10 - 20 min and stop for 7 - 12 min in one cycle. This is beneficial to the dispersion of raw materials, thereby helping to improve the adhesion of the porous carbon electrode layer and reduce the internal resistance.

[0048] The mixture formed by ethyl cellulose and terpineol can be mixed with mixture A in a nano ultrasonic disperser. The frequency of the nano ultrasonic disperser can be 10 - 30 KHz; preferably 15 - 25 KHz. The treatment time can be 70 - 150 min; preferably 90 - 120 min. The intermittent treatment method can be adopted, with 10 - 20 min of operation and 7 - 12 min of stop in one cycle. Preferably, under stirring conditions, the mixture formed by ethyl cellulose and terpineol is added to mixture A. This is beneficial to the dispersion of raw materials, thus helping to improve the adhesion of the porous carbon electrode layer and reduce the internal resistance.

[0049] In the present invention, the perovskite precursor solution can be dropped into the second porous carbon electrode layer by drop coating. The perovskite precursor solution includes perovskite and a solvent. The structure of the perovskite is as described above. The solvent can be selected from one or more of γ - butyrolactone, N,N - dimethylformamide, N - methylformamide, N - methylpyrrolidone or dimethyl sulfoxide; preferably γ - butyrolactone. The mass fraction of the solute in the perovskite precursor slurry can be 15 - 45 wt%; preferably 25 - 35 wt%.

[0050] In the above step (2), after the perovskite precursor solution diffuses and infiltrates into the pores of the first porous carbon electrode layer and the second porous carbon electrode layer, annealing can also be carried out. The annealing temperature can be 50 - 150 °C; preferably 50 - 100 °C. In a perovskite solar cell having a porous electron transport layer and a porous insulating spacer layer, the perovskite precursor solution diffuses and infiltrates into the pores of the porous electron transport layer and the porous insulating spacer layer.

[0051] In the preparation method of the present invention, it can also include: (A) an etching step; (B) a step of forming a dense layer; (C) a step of forming a porous electron transport layer; (D) a step of forming a porous insulating spacer layer; (E) one or more steps of the step of forming the first porous carbon electrode layer.

[0052] Etching step: Etch on the conductive layer covering the transparent substrate to form an insulating strip, thereby dividing the transparent substrate and the conductive layer into a positive electrode region and a negative electrode region. A laser can be used for etching.

[0053] Step of forming a dense layer: Spray a dense titanium dioxide thin film on the conductive layer to form a dense layer. According to an embodiment of the present invention, spray a dense titanium dioxide thin film on the upper surface of the conductive layer in the negative electrode region to form a dense layer. The spraying can be carried out at 300 - 600 °C; preferably 400 - 500 °C.

[0054] Steps for forming a porous electron transport layer: Printing a porous electron transport layer slurry on the dense layer to form a porous electron transport layer. According to an embodiment of the present invention, printing the porous electron transport layer slurry on the upper surface of the dense layer to form a porous electron transport layer. A screen printing machine can be used for printing. After printing, steps of drying and / or sintering can also be carried out. The sintering temperature can be 300 - 600 °C; preferably 400 - 550 °C.

[0055] Steps for forming a porous insulating spacer layer: Printing a porous insulating spacer layer slurry on the porous electron transport layer to form a porous insulating spacer layer. According to an embodiment of the present invention, printing the porous insulating spacer layer slurry on the porous electron transport layer, such that the porous insulating spacer layer slurry completely covers the porous electron transport layer and fills into the insulating band, followed by drying to form a porous insulating spacer layer. A screen printing machine can be used for printing. Sintering can also be carried out after drying. The sintering temperature can be 300 - 600 °C; preferably 400 - 550 °C.

[0056] Steps for forming a first porous carbon electrode layer: Printing a first porous carbon electrode layer slurry on the porous insulating spacer layer to form a first porous carbon electrode layer. According to an embodiment of the present invention, printing the first porous carbon electrode layer slurry on the upper surface of the porous carbon insulating spacer layer and the upper surface of the conductive layer in the positive electrode region to form a first porous carbon electrode layer. A screen printing machine can be used for printing. After printing, steps of drying and / or sintering can also be carried out. The sintering temperature can be 300 - 600 °C; preferably 400 - 550 °C.

[0057] The first porous carbon electrode layer slurry may contain graphite, carbon black, ethyl cellulose, zirconium dioxide, and terpineol. Based on 1 part by weight of carbon black, the amount of graphite used can be 1 - 6 parts by weight, preferably 2 - 4 parts by weight; the amount of ethyl cellulose used can be 0.1 - 1 part by weight, preferably 0.3 - 0.7 part by weight; the amount of zirconium dioxide used can be 0.1 - 1 part by weight, preferably 0.3 - 0.7 part by weight; the amount of terpineol used can be 2 - 5 parts by weight, preferably 3 - 4 parts by weight.

[0058] The preparation method of the first porous carbon electrode layer may include the following steps: Mixing graphite, carbon black, ethyl cellulose, zirconium dioxide, and terpineol together to form a mixture; processing the mixture in a ball mill to form the first porous carbon electrode layer slurry. The rotational speed of the ball mill can be 200 - 500 r / min; preferably 250 - 400 r / min. The processing time in the ball mill can be 10 - 18 h; preferably 11 - 15 h.

[0059] On the other hand, the present invention provides a preparation method of a perovskite solar cell module, which includes the following steps:

[0060] (1) N etching lines are etched on the conductive layer covering the transparent substrate to form N insulating bands, thereby dividing the transparent substrate and the conductive layer into N positive electrode regions and N negative electrode regions; where N is a positive integer greater than or equal to 2;

[0061] (2) A dense layer is formed on the upper surface of the conductive layer in the negative electrode region;

[0062] (3) A porous electron transport layer is formed on the upper surface of the dense layer;

[0063] (4) A porous insulating spacer layer is formed on the porous electron transport layer, so that the porous insulating spacer layer covers the entire porous electron transport layer and fills into the insulating bands;

[0064] (5) A first porous carbon electrode layer slurry is printed on the upper surface of the porous insulating spacer layer and the upper surface of the conductive layer in the positive electrode region to form a first porous carbon electrode layer;

[0065] (6) A second porous carbon electrode layer slurry is printed on the upper surface of the first porous carbon electrode layer to form a second porous carbon electrode layer;

[0066] (7) The perovskite precursor solution is dropped into the second porous carbon electrode layer, so that the perovskite precursor solution diffuses and infiltrates into the pores of the porous electron transport layer, the porous insulating spacer layer, the first porous carbon electrode layer and the second porous carbon electrode layer;

[0067] The first porous carbon electrode layer slurry includes graphite, carbon black, zirconia, terpineol and ethyl cellulose;

[0068] The second porous carbon electrode layer slurry includes graphite, carbon black, zirconia, terpineol and ethyl cellulose.

[0069] According to an embodiment of the present invention, a method for preparing a perovskite solar cell module includes the following steps:

[0070] (1) Using a laser to etch N mutually parallel etching lines on the conductive layer covering the transparent substrate to form N insulating bands, thereby dividing the transparent substrate and the conductive layer into N positive electrode regions and N negative electrode regions; where N is a positive integer greater than or equal to 2;

[0071] (2) At 400 - 500 °C, a dense titanium dioxide thin film is sprayed on the upper surface of the conductive layer in the negative electrode region to form a dense layer;

[0072] (3) Printing a porous electron transport layer slurry on the upper surface of the dense layer using a screen printer, drying, and then sintering at 400 - 550 °C to form a porous electron transport layer;

[0073] (4) A porous insulating spacer layer paste is printed on the porous electron transport layer using a screen printing machine, such that the porous insulating spacer layer paste covers the entire porous electron transport layer and fills into the insulating band, and is dried to form a porous insulating spacer layer;

[0074] (5) A first porous carbon electrode layer paste is printed on the upper surface of the porous carbon insulating spacer layer and the upper surface of the conductive layer in the positive electrode region using a screen printing machine, and is dried to form a first porous carbon electrode layer;

[0075] (6) A second porous carbon electrode layer paste is printed on the upper surface of the first porous carbon electrode layer using a screen printing machine, such that the second porous carbon electrode layer slurry completely covers the upper surface of the first porous carbon electrode layer, and is dried, and then sintered at 400 - 550 °C to form a second porous carbon electrode layer;

[0076] (7) The perovskite precursor solution is dropped into the second porous carbon electrode layer, such that the perovskite precursor solution diffuses and infiltrates into the pores of the porous electron transport layer, the porous insulating spacer layer, the first porous carbon electrode layer, and the second porous carbon electrode layer, and then annealed at 50 - 100 °C to obtain a perovskite solar cell module;

[0077] The first porous carbon electrode layer paste includes graphite, carbon black, zirconia, terpineol, and ethyl cellulose;

[0078] The second porous carbon electrode layer paste includes graphite, carbon black, zirconia, terpineol, and ethyl cellulose.

[0079] The particle size of graphite in the first porous carbon electrode layer paste is 0.2 - 30 μm; preferably 1 - 20 μm; preferably 5 - 15 μm.

[0080] The particle size of graphite in the second porous carbon electrode layer paste is 0.1 - 10 μm;; preferably 0.3 - 5 μm; preferably 0.5 - 2 μm.

[0081] The particle size of graphite in the second porous carbon electrode layer paste is smaller than that in the first porous carbon electrode layer paste.

[0082] The thickness of the first porous carbon electrode layer can be 5 - 100 μm; preferably 10 - 40 μm.

[0083] The thickness of the second porous carbon electrode layer can be 10 - 500 μm; preferably 15 - 100 μm.

[0084] The slurry of the first porous carbon electrode layer may contain graphite, carbon black, ethyl cellulose, zirconia and terpineol. Based on 1 part by weight of carbon black, the amount of graphite used may be 1 to 6 parts by weight, preferably 2 to 4 parts by weight; the amount of ethyl cellulose used may be 0.1 to 1 part by weight, preferably 0.3 to 0.7 part by weight; the amount of zirconia used may be 0.1 to 1 part by weight, preferably 0.3 to 0.7 part by weight; the amount of terpineol used may be 2 to 5 parts by weight, preferably 3 to 4 parts by weight.

[0085] The preparation method of the first porous carbon electrode layer may include the following steps: mixing graphite, carbon black, ethyl cellulose, zirconia and terpineol together to form a mixture; processing the mixture in a ball mill to form a slurry of the first porous carbon electrode layer. The rotational speed of the ball mill may be 200 to 500 r / min; preferably 250 to 400 r / min. The processing time in the ball mill may be 10 to 18 h; preferably 11 to 15 h.

[0086] In the slurry of the second porous carbon electrode layer of the invention, based on 1 part by weight of carbon black, the amount of graphite used may be 1 to 6 parts by weight, preferably 2 to 4 parts by weight; the amount of ethyl cellulose used may be 0.1 to 1 part by weight, preferably 0.3 to 0.7 part by weight; the amount of zirconia used may be 0.1 to 1 part by weight, preferably 0.3 to 0.7 part by weight; the amount of terpineol used may be 2 to 5 parts by weight, preferably 3 to 4 parts by weight.

[0087] The preparation method of the second porous carbon electrode layer slurry may include the following steps: forming a mixture A of graphite, carbon black and a solvent; mixing the mixture formed by ethyl cellulose and terpineol with the mixture A; evaporating the solvent to obtain the second porous carbon electrode layer slurry. This is beneficial to the dispersion of raw materials, thereby helping to improve the adhesion of the porous carbon electrode layer and reduce the internal resistance.

[0088] The solvent may be an alcohol solvent. Examples of the alcohol solvent include but are not limited to one or more of methanol, ethanol, propanol, and isopropanol. According to an embodiment of the present invention, the solvent is anhydrous ethanol.

[0089] The mixture A may be formed by a nano ultrasonic disperser. The frequency of the nano ultrasonic disperser may be 10 to 30 KHz; preferably 15 to 25 KHz. The processing time may be 70 to 150 min; preferably 90 to 120 min. An intermittent processing method may be adopted, setting to work for 10 to 20 min and stop for 7 to 12 min in one cycle. This is beneficial to the dispersion of raw materials, thereby helping to improve the adhesion of the porous carbon electrode layer and reduce the internal resistance.

[0090] The mixture formed by ethyl cellulose and terpineol can be mixed with mixture A in a nano ultrasonic disperser. The frequency of the nano ultrasonic disperser can be 10 - 30 KHz; preferably 15 - 25 KHz. The treatment time can be 70 - 150 min; preferably 90 - 120 min. The intermittent treatment method can be adopted, setting to work for 10 - 20 min and stop for 7 - 12 min in one cycle. Preferably, under the condition of stirring, the mixture formed by ethyl cellulose and terpineol is added to mixture A. This is beneficial to the dispersion of raw materials, thus helping to improve the adhesion of the porous carbon electrode layer and reduce the internal resistance.

[0091] In the present invention, the perovskite precursor solution can be dropped into the second porous carbon electrode layer by drop coating. The perovskite precursor solution includes perovskite and a solvent. The structure of the perovskite is as described above. The solvent can be selected from one or more of γ-butyrolactone, N,N-dimethylformamide, N-methylformamide, N-methylpyrrolidone or dimethyl sulfoxide; preferably γ-butyrolactone. The mass fraction of the solute in the perovskite precursor slurry can be 15 - 45 wt%; preferably 25 - 35 wt%. Brief Description of the Drawings

[0092] Figure 1 It is a schematic structural diagram of the perovskite solar cell of the present invention.

[0093] Figure 2 It is a schematic structural diagram of the perovskite solar cell module of the present invention.

[0094] Figure 3 It is a physical diagram of the perovskite solar cell module of the present invention and the perovskite solar cell module of the comparative example; wherein, A is the physical diagram of the perovskite solar cell module of Comparative Example 1, and B is the physical diagram of the perovskite solar cell module of Example 1.

[0095] As shown in the figure, the markings are detailed as follows:

[0096] 1 - transparent substrate; 2 - conductive layer; 3 - dense layer; 4 - porous electron transport layer; 5 - porous insulating spacer layer; 6 - first porous carbon electrode layer; 7 - second porous carbon electrode layer; 8 - perovskite solar cell; 9 - insulating tape. Detailed Description of the Invention

[0097] In the following examples and comparative examples:

[0098] The transparent substrate is formed of glass; the conductive layer is formed of fluorine-doped tin oxide; the cleaning agent is III cleaning agent.

[0099] Example 1

[0100] As Figure 2As shown, the perovskite solar cell module of this embodiment is formed by connecting 9 groups of perovskite solar cells 8 in series. As Figure 2 shown, the size of the transparent substrate 1 is 120×120 mm. The conductive layer 2 covers the upper surface of the transparent substrate 1. There are 9 mutually parallel etching lines on the conductive layer 2, forming 9 insulating bands 9, thereby separating the transparent substrate 1 and the conductive layer 2 into 9 positive electrode regions and 9 negative electrode regions, constituting a structure in which 9 groups of perovskite solar cells 8 are connected in series.

[0101] As Figure 1 shown, each group of perovskite solar cells 8 includes the transparent substrate 1 and the conductive layer 2, the dense layer 3, the porous electron transport layer 4, the porous insulating spacer layer 5, the first porous carbon electrode layer 6, the second porous carbon electrode layer 7 in one positive electrode region and one negative electrode region, and the perovskite filled in the porous electron transport layer 4, the porous insulating spacer layer 5, the first porous carbon electrode layer 6, and the second porous carbon electrode layer 7. The dense layer 3 covers the upper surface of the conductive layer 2 in the negative electrode region. The porous electron transport layer 4 covers the upper surface of the dense layer 3. The porous insulating spacer layer 5 covers the entire porous electron transport layer 4 and fills into the insulating band 9. The first porous carbon electrode layer 6 covers the upper surface of the porous insulating spacer layer 5 and the upper surface of the conductive layer 2 in the positive electrode region. The second porous carbon electrode layer 7 covers the upper surface of the first porous carbon electrode 6. The perovskite fills into the pores of the porous electron transport layer 4, the porous insulating spacer layer 5, the first porous carbon electrode layer 6, and the second porous carbon electrode layer 7.

[0102] The preparation method of the perovskite solar cell module of this embodiment is as follows:

[0103] (1) On the conductive layer 2 covering the transparent substrate 1 (with a size of 120×120 mm), 9 mutually parallel etching lines are etched using a laser to form 9 insulating bands 9, thereby separating the transparent substrate 1 and the conductive layer 2 into 9 positive electrode regions and 9 negative electrode regions, constituting a structure in which 9 groups of perovskite solar cells 8 are connected in series. The etched transparent substrate 1 and conductive layer 2 are ultrasonically cleaned successively with detergent, distilled water, and absolute ethanol.

[0104] (2) At 450 °C, a dense titanium dioxide thin film is sprayed on the upper surface of the conductive layer 2 in the negative electrode region to form the dense layer 3.

[0105] (3) On the upper surface of the dense layer 3, a porous electron transport layer slurry containing titanium dioxide is printed using a screen printing machine, dried, and then sintered at 500 °C to form the porous electron transport layer 4.

[0106] (4) A porous insulating spacer paste containing zirconia is printed on the porous electron transport layer 4 using a screen printing machine, such that the porous insulating spacer paste completely covers the porous electron transport layer 4 and fills into the insulating strip 9, and then dried to form a porous insulating spacer layer 5.

[0107] (5) A first porous carbon electrode layer paste is printed on the upper surface of the porous carbon insulating spacer layer 5 and the upper surface of the conductive layer 2 in the positive electrode region using a screen printing machine, and then dried to form a first porous carbon electrode layer 6 (with a thickness of 20 μm);

[0108] The preparation method of the first porous carbon electrode layer slurry is as follows: Graphite (with an average particle size of 10 μm), carbon black, ethyl cellulose, zirconia, and terpineol with a mass ratio of 3∶1∶0.5∶0.5∶3.5 are mixed together, and an appropriate amount of absolute ethanol is added to form a mixture; the mixture is processed in a ball mill at a rotation speed of 300 r / min for 12 h, and the absolute ethanol is evaporated using a rotary evaporator to obtain the first porous carbon electrode layer paste.

[0109] (6) A second porous carbon electrode layer paste is printed on the upper surface of the first porous carbon electrode layer 6 using a screen printing machine, such that the second porous carbon electrode layer slurry completely covers the upper surface of the first porous carbon electrode layer 6, and then dried, and then sintered at 500 °C to form a second porous carbon electrode layer 7 (with a thickness of 30 μm);

[0110] The preparation method of the second porous carbon electrode layer slurry is as follows: Graphite (with an average particle size of 1 μm), carbon black, zirconia, and absolute ethanol with a mass ratio of 3∶1∶0.5 are placed in a nano ultrasonic disperser and intermittently processed at a frequency of 20 KHz for 100 min (set to work for 15 min and stop for 10 min in one cycle, a total of 4 cycles) to form a mixture A. Then, under stirring conditions, a mixture of ethyl cellulose and terpineol (with a mass ratio of ethyl cellulose to terpineol of 0.5∶3.5) that is uniformly mixed is added to mixture A, and nano ultrasonic disperser ultrasonic intermittent treatment is performed for 100 min (frequency of 20 KHz, set to work for 15 min and stop for 10 min in one cycle, a total of 4 cycles). The absolute ethanol is evaporated using a rotary evaporator to obtain the second porous carbon electrode layer paste.

[0111] (7) The perovskite precursor solution (solute is methylammonium lead iodide, solvent is γ-butyrolactone, and the solute mass fraction is 30 wt%) is dropped at the middle of the upper surface of the second porous carbon electrode layer 7 using a drop coating method. The filling amount of the perovskite precursor solution is 0.5 ml, and it is left standing to allow the perovskite precursor solution to uniformly and fully diffuse and infiltrate into the pores of the porous electron transport layer 4, the porous insulating spacer layer 5, the first porous carbon electrode layer 6, and the second porous carbon electrode layer 7, and then annealed at 50 °C to obtain the perovskite solar cell module.

[0112] Comparative Example 1

[0113] The difference between the perovskite solar cell module of Comparative Example 1 and that of Example 1 is only that the second porous carbon electrode layer 7 is replaced by a third porous carbon electrode layer.

[0114] Steps (1) to (5) and (7) of the preparation methods of Comparative Example 1 and Example 1 are the same. The difference lies in that step (6) is replaced by step (6A), and step (6A) is specifically as follows:

[0115] (6A) Print the slurry of the third porous carbon electrode layer on the upper surface of the first porous carbon electrode layer by using a screen printing machine, so that the slurry of the third porous carbon electrode layer completely covers the upper surface of the first porous carbon electrode layer. After drying, sinter at 500 °C to form the third porous carbon electrode layer (with a thickness of 30 μm);

[0116] The slurry of the third porous carbon electrode layer is the same as that of the first porous carbon electrode slurry.

[0117] From Figure 3 It can be seen that the upper surfaces of the first porous carbon electrode layer and the second porous carbon electrode layer of the perovskite solar cell module of Example 1 are still flat after drop-coating the perovskite precursor solution, while there is obvious warping at the place where the perovskite precursor solution is drop-coated on the third carbon electrode layer of the perovskite solar cell module of Comparative Example 1.

[0118] Experimental Example

[0119] The perovskite solar cell modules of Example 1 and Comparative Example 1 were tested by using the current-voltage curve test method: Before the test, the solar simulator was calibrated by using a standard silicon cell of the National Renewable Energy Laboratory (NREL) so that the light intensity was 1 standard sunlight (AM 1.5G, 100 mW / cm 2 ). Place the perovskite solar cell module to be tested at the center of the solar simulator, set the starting voltage to 9 V, the ending voltage to -1 V, the voltage step to -0.1 V, the effective area to 6007.5 mm 2 , the number of test times to 2 times, the period to 2 min. After the test, record the relevant data and take the average value. The obtained results are shown in Table 1.

[0120] Table 1

[0121]

[0122] The present invention is not limited to the above embodiments. Without departing from the essence of the present invention, any deformation, improvement, or replacement that can be conceived by those skilled in the art falls within the scope of the present invention.

Claims

1. A preparation method of a perovskite solar cell, characterized in that It includes the following steps: (1) Treat graphite, carbon black and a solvent with a nano ultrasonic disperser at a frequency of 10 - 30 KHz to form mixture A; mix the mixture formed by ethyl cellulose and terpineol with mixture A in a nano ultrasonic disperser at a frequency of 10 - 30 KHz; evaporate the solvent to obtain the second porous carbon electrode layer slurry; the solvent is selected from one or more of methanol, ethanol, propanol, and isopropanol; Print the second porous carbon electrode layer slurry on the first porous carbon electrode layer to form the second porous carbon electrode layer; (2) Drop the perovskite precursor solution into the second porous carbon electrode layer, and allow the perovskite precursor solution to diffuse and infiltrate into the pores of the first porous carbon electrode layer and the second porous carbon electrode layer; The slurry of the second porous carbon electrode layer includes graphite, carbon black, zirconia, terpineol and ethyl cellulose; the particle size of the graphite is 0.5 - 2 μm; based on 1 part by weight of carbon black, the dosage of graphite is 2 - 4 parts by weight, and the dosage of zirconia is 0.3 - 0.7 parts by weight; The perovskite solar cell includes a first porous carbon electrode layer and a second porous carbon electrode layer, and the second porous carbon electrode layer covers the upper surface of the first porous carbon electrode layer; The first porous carbon electrode layer is formed from a first porous carbon electrode layer slurry containing graphite, and the particle size of the graphite in the first porous carbon electrode layer slurry is 5 - 15 μm; The perovskite solar cell further includes a transparent substrate, a conductive layer, a dense layer, a porous electron transport layer, a porous insulating spacer layer, and perovskite filled in the pores of the porous electron transport layer, the porous insulating spacer layer, the first porous carbon electrode layer and the second porous carbon electrode layer, which are stacked in sequence from bottom to top; the first porous carbon electrode layer covers the porous insulating spacer layer.

2. The preparation method according to claim 1, characterized in that, Put graphite, carbon black and zirconia with a mass ratio of 3:1:0.5 and absolute ethanol into a nano ultrasonic disperser, and intermittently treat it at a frequency of 20 KHz for 100 min to form mixture A; among them, the average particle size of the graphite is 1 μm; Then, under stirring conditions, add the mixture of ethyl cellulose and terpineol which is uniformly mixed to mixture A; among them, the mass ratio of ethyl cellulose to terpineol is 0.5:3.5; intermittently treat it with a nano ultrasonic disperser for 100 min, and the frequency of the nano ultrasonic disperser is 20 KHz; Use a rotary evaporator to evaporate the absolute ethanol to obtain the second porous carbon electrode layer slurry; The intermittent treatment is set to work for 15 min and stop for 10 min in one cycle, with a total of 4 cycles.

3. The preparation method according to claim 1, characterized in that, The first porous carbon electrode layer slurry is formed from raw materials containing graphite, carbon black and zirconia.

4. The preparation method according to claim 3, wherein The mass ratio of graphite, carbon black and zirconia in the first porous carbon electrode layer slurry is (1 - 6):1:(0.1 - 1).

5. The preparation method according to claim 1, characterized in that, The thickness of the second porous carbon electrode layer is 10 - 500 μm.

6. The preparation method according to claim 1, characterized in that, The conductive layer has an insulating band formed by etching lines, thereby dividing the transparent substrate and the conductive layer into a negative electrode region and a positive electrode region; The dense layer covers the upper surface of the conductive layer in the negative electrode region; The porous electron transport layer covers the upper surface of the dense layer; The porous insulating spacer layer covers the entire porous electron transport layer and is filled into the insulating strips; The first porous carbon electrode layer covers the upper surface of the mesoporous insulating spacer layer and the upper surface of the conductive layer in the positive electrode region; The second porous carbon electrode layer covers the upper surface of the first porous carbon electrode layer.

7. The preparation method according to claim 1, wherein The conductive layer is formed of fluorine-doped tin oxide or indium tin oxide; the dense layer is formed of titanium dioxide; the porous electron transport layer is formed of titanium dioxide, tin oxide or barium stannate; the insulating spacer layer is formed of zirconium dioxide, silicon dioxide or aluminum oxide.

8. A perovskite solar cell module, characterized in that, Including at least two groups of perovskite solar cells obtained by the preparation method according to any one of claims 1 to 7, and the perovskite solar cells are connected in series.

9. The manufacturing method of the perovskite solar cell module according to claim 8, characterized in that, Including the following steps: (1) Etching N etching lines on the conductive layer covering the transparent substrate to form N insulating strips, thereby dividing the transparent substrate and the conductive layer into N positive electrode regions and N negative electrode regions; wherein, N is a positive integer greater than or equal to 2; (2) Forming a dense layer on the upper surface of the conductive layer in the negative electrode region; (3) Forming a porous electron transport layer on the upper surface of the dense layer; (4) Forming a porous insulating spacer layer on the porous electron transport layer, so that the porous insulating spacer layer covers the entire porous electron transport layer and is filled into the insulating strips; (5) Printing a first porous carbon electrode layer slurry on the upper surface of the porous insulating spacer layer and the upper surface of the conductive layer in the positive electrode region to form a first porous carbon electrode layer; (6) Printing a second porous carbon electrode layer slurry on the upper surface of the first porous carbon electrode layer to form a second porous carbon electrode layer; (7) Dropping a perovskite precursor solution into the second porous carbon electrode layer, so that the perovskite precursor solution diffuses and infiltrates into the pores of the porous electron transport layer, the porous insulating spacer layer, the first porous carbon electrode layer and the second porous carbon electrode layer; The first porous carbon electrode layer slurry includes graphite, carbon black, zirconium dioxide, terpineol and ethyl cellulose; The second porous carbon electrode layer slurry includes graphite, carbon black, zirconium dioxide, terpineol and ethyl cellulose.

Images