Cadmium telluride / crystalline silicon laminated solar cell module and preparation method thereof

Abstract

The invention relates to the technical field of solar cells, in particular to a cadmium telluride / crystalline silicon laminated solar cell module and a preparation method thereof.The cadmium telluride / crystalline silicon laminated solar cell module comprises a cadmium telluride cell, a crystalline silicon cell and TCO glass with an n-type cadmium sulfide / p-type cadmium telluride heterojunction cell deposited on the front surface, a first adhesive film layer, a crystalline silicon cell layer, a second adhesive film layer, backboard glass and an integrated junction box are sequentially stacked, the cadmium telluride cell and the crystalline silicon cell are mechanically stacked and interconnected, the first adhesive film layer and the second adhesive film layer are POE or PVB adhesive films, and the crystalline silicon cell layer is formed by connecting a plurality of monocrystalline silicon cells in series, specifically PERT, TOPCon, HJT or XBC cells; according to the cell structure provided by the invention, the output power of the photovoltaic module can be improved, the limitation that the power of the current single-junction solar cell module cannot reach 800W is solved, and the stability problem of the current crystalline silicon and perovskite laminated photovoltaic module is effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a cadmium telluride / crystalline silicon laminated solar cell module and a preparation method thereof. BACKGROUND

[0002] The theoretical efficiency limit of single-junction cadmium telluride solar cells is 32% (based on the Shockley-Queisser model), and the highest efficiency in the world laboratory has reached 23.1%. The efficiency of cadmium telluride solar cells depends on structural innovation and material optimization, and the industrialization process has shifted from single-efficiency competition to "efficiency-cost-stability" coordinated upgrading. The average conversion efficiency of large-area mass-produced cadmium telluride photovoltaic modules exceeds 18%.

[0003] The theoretical efficiency limit of single-junction cadmium telluride solar cells is 32% (based on the Shockley-Queisser model), and the highest efficiency in the world laboratory has reached 23.1%. The efficiency of cadmium telluride solar cells depends on structural innovation and material optimization, and the industrialization process has shifted from single-efficiency competition to "efficiency-cost-stability" coordinated upgrading. The average conversion efficiency of large-area mass-produced cadmium telluride photovoltaic modules exceeds 18%.

[0004] However, perovskite photovoltaic technology faces the challenge of balancing large area, conversion efficiency, and cost. Currently, it is a major challenge to produce a conversion efficiency of more than 20% on a conductive glass larger than 2.5 square meters, not to mention achieving a conversion efficiency of more than 23.5% commonly seen in crystalline silicon photovoltaic modules. In order to solve the problem of low efficiency of cadmium telluride solar cells, combining the most mature low-cost crystalline silicon photovoltaic technology in the industry chain is the best solution. Cadmium telluride / crystalline silicon laminated photovoltaic technology not only overcomes the problem of low conversion efficiency of cadmium telluride, but also reduces the manufacturing cost, and solves the problem of instability after laminating crystalline silicon and other perovskite solar cells. SUMMARY

[0005] The present application aims to provide a cadmium telluride / crystalline silicon laminated solar cell module and a preparation method thereof to solve the problems raised in the background.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a cadmium telluride / crystalline silicon laminated solar cell module, comprising a cadmium telluride cell and a crystalline silicon cell, a TCO glass on which an n-type cadmium sulfide / p-type cadmium telluride heterojunction cell is deposited on the front surface, a first adhesive film layer, a crystalline silicon cell layer, a second adhesive film layer and a back panel glass are sequentially laminated.

[0007] Preferably, the cadmium telluride cell and the crystalline silicon cell are mechanically stacked and interconnected.

[0008] Preferably, the first adhesive film layer and the second adhesive film layer are POE or PVB adhesive films.

[0009] Preferably, a high-transmittance heat-resistant insulating separation layer is further included between the first adhesive film layer and the crystalline silicon cell layer, and the high-transmittance heat-resistant insulating separation layer is a POE adhesive film or a PVB adhesive film or a POE and / or PVB and / or EVA mixed co-extrusion adhesive film doped with a scattering layer of silica nanoparticles.

[0010] Preferably, the crystalline silicon cell layer is composed of a plurality of single-crystal silicon cell series, specifically PERT, TOPCon, HJT, and XBC solar cells.

[0011] Preferably, the cadmium telluride and the crystalline silicon use a dual-circuit independent output design, and only the same type of battery circuit is allowed to be interconnected between the components.

[0012] Preferably, the back glass is an ultra-thin grid glazed back glass or an ultra-thin chemical toughened glass or a patterned ultra-thin glass.

[0013] A method for preparing the cadmium telluride / crystalline silicon laminated solar cell described above, comprising the following steps: S1: laser scribing to define electrodes on the TCO glass; S2: growing the core device layer of the cadmium telluride solar cell of N-type cadmium sulfide and P-type cadmium telluride and a carrier transport layer, and then defining the sub-cells by laser scribing; S3: depositing electrode material and then defining electrodes by laser scribing; S4: using laser to make isolation scribing along the edge of the TCO glass; S5: using a soldering machine to lead out the positive and negative electrodes of the cadmium telluride sub-cells after series connection and the bus bar; S6: using the TCO glass of the cadmium telluride cell component as the front glass of the crystalline silicon photovoltaic component, adopting the production process flow of the conventional crystalline silicon photovoltaic component, laying the POE or PVB or POE and / or PVB and / or EVA mixed co-extrusion adhesive film doped with a scattering layer of silica nanoparticles on the TCO glass, using a high-transmittance heat-resistant separation plate or directly laying on the crystalline silicon cell piece series, then welding the positive and negative bus bars of the crystalline silicon cell series, laying the adhesive film described above, and finally laying the back glass, and then performing edge trimming, gluing, and frame mounting after lamination.

[0014] S7: the cadmium telluride sub-cell series and the crystalline silicon sub-cell series are connected to an integrated junction box by different lead-out wires, one of which is the positive and negative electrodes of the cadmium telluride cell, and the other of which is the positive and negative electrodes of the crystalline silicon, the wires between the components are connected in a plug-in manner using matching male and female heads, and the wiring cables of the cadmium telluride and the crystalline silicon use different colors and the wiring male and female heads use different sizes, so as to distinguish the battery wiring of different components.

[0015] S8: testing and passing to complete the cadmium telluride / crystalline silicon laminated solar cell component.

[0016] Compared with the prior art, the present application has the following advantages: The battery structure provided by the present application can improve the output power of the photovoltaic module. The energy band gap of cadmium telluride is in the range of 1.45-1.50 eV, and the response spectrum range of sunlight is 300-850 nm. The energy band gap of monocrystalline silicon is 1.12 eV, and the response spectrum range of sunlight is 300-1100 nm. The two form complementary absorption, and the theoretical efficiency can reach 42%. The photoelectric conversion efficiency of the laminated structure of the two is also easy to exceed the bottleneck of the current single-junction solar cell industrialization efficiency of 27%. The output power of the photovoltaic module can reach 700 W to 870 W, solving the difficulty that the output power of the current single-junction photovoltaic module is difficult to exceed 700 W, and even more difficult to reach 800 W.

[0017] The battery structure provided by the present application also enhances the stability of the laminated photovoltaic module, realizes the long-term reliability of the cadmium telluride solar cell module and the stability of the device itself, and combines the crystal silicon technology which has been verified as long-term stable and feasible as the cadmium telluride battery. Not only does it solve the limitation that the power of the current single-junction solar cell module cannot reach 800 W, but it also effectively solves the stability problem of the current crystal silicon and other laminated photovoltaic modules such as perovskite. The present application adopts a mechanical stacking architecture, effectively avoids the chemical interface reaction of the cadmium telluride thin film laminates, and has a decay rate of <1% / year under damp heat test (85℃ / 85%RH), meeting the requirements of industrial production; The independent circuit design can isolate the double system faults, and the local failure does not affect the overall output, ensuring that there is no risk of mixed connection between the modules and improving the system reliability. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a schematic diagram of a cadmium telluride / crystal silicon laminated solar cell structure without a high-transparency heat-resistant insulating isolation layer. Figure 2 It is a manufacturing process flow of a cadmium telluride / crystal silicon laminated solar cell with a high-transparency heat-resistant insulating isolation layer. Figure 3 It is a schematic diagram of a cadmium telluride / crystal silicon laminated solar cell structure without a high-transparency heat-resistant insulating isolation layer. In the figure, TCO glass-1, n-type cadmium sulfide / p-type cadmium telluride heterojunction battery-2, first adhesive film layer-3, high-transparency heat-resistant insulating isolation layer-4, crystal silicon battery layer-5, second adhesive film layer-6, back panel glass-7, and integrated junction box-8. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0020] Please refer to Figure 1 The present application provides a technical solution: a cadmium telluride / crystalline silicon laminated solar cell module, comprising a cadmium telluride cell and a crystalline silicon cell, the cadmium telluride cell and the crystalline silicon cell are mechanically stacked and interconnected, the front surface is a TCO glass 1 of a deposited n-type cadmium sulfide / p-type cadmium telluride heterojunction cell 2, sequentially stacked are a first adhesive film layer 3, a high-transmittance heat-resistant insulating isolation layer 4, a crystalline silicon cell layer 5, a second adhesive film layer 6, and an ultrathin grid glazed backboard glass 7. The first adhesive film layer 3 and the second adhesive film layer 6 are POE or PVB adhesive films; The high-transmittance heat-resistant insulating isolation layer 4 is a POE adhesive film or a PVB adhesive film or a POE and / or PVB and / or EVA mixed co-extrusion adhesive film doped with a silica nanoparticle scattering layer, which can not only ensure light transmittance but also achieve heat resistance, preventing the occurrence of hot spots and the resulting burning through, which can cause short-circuit contact between two sub-cell strings and direct current arc, leading to a fire. The high-transmittance heat-resistant insulating isolation layer 4 is an optional item. If the isolation layer is included, the cadmium telluride / crystalline silicon laminated solar cell module is a 7-layer structure. If the isolation layer is not included, the cadmium telluride / crystalline silicon laminated solar cell module is a 6-layer structure.

[0021] The TCO glass 1 directly replaces the traditional crystalline silicon front plate, achieving mechanical stacking and optical coupling of the cadmium telluride cell and the crystalline silicon cell.

[0022] The crystalline silicon cell layer 5 is composed of a plurality of single-crystal silicon cell strings, specifically PERT, TOPCon, HJT, and XBC cells.

[0023] The cadmium telluride and the crystalline silicon use a double-circuit independent output design. The cadmium telluride sub-cell string and the crystalline silicon sub-cell string are connected to an integrated junction box using different lead-out wires. The junction box is provided with two output wires, one being the positive and negative electrodes of the cadmium telluride cell, and the other being the positive and negative electrodes of the crystalline silicon. The wires between the modules are connected in a plug-in manner using matching male and female heads. The junction cables of the cadmium telluride and the crystalline silicon use different colors, and the junction male and female heads use different sizes, thereby distinguishing the cell junctions of different modules.

[0024] Only the same type of cell circuit is allowed to be interconnected between modules (cadmium telluride-cadmium telluride, crystalline silicon-crystalline silicon), ensuring that there is no risk of mixed connection between modules and improving system reliability.

[0025] The application also provides a technical solution: a preparation method of a cadmium telluride / crystalline silicon laminated solar cell module, comprising the following steps: S1: laser scribing to define electrodes on the TCO glass 1; S2: growing core device layers of a cadmium telluride solar cell including N-type cadmium sulfide and P-type cadmium telluride and a carrier transport layer, and then defining sub-cells by laser scribing; S3: depositing electrode materials, and then defining electrodes by laser scribing; S4: using laser to make isolation scribing along the edge of the TCO glass; S5: using a soldering machine to connect bus bars to the positive and negative electrodes of all cadmium telluride sub-cells; S6: using the TCO glass 1 of the cadmium telluride cell module as the front plate glass of a crystalline silicon photovoltaic module, using the production process of a conventional crystalline silicon photovoltaic module, laying POE or PVB film on the TCO glass 1, laying isolation plates or directly laying crystalline silicon cell pieces in series, soldering crystalline silicon bus bars, laying POE film, and finally laying back glass, and then performing edge trimming, glueing and frame mounting after lamination.

[0026] S7: connecting the cadmium telluride sub-cell string and the crystalline silicon sub-cell string to an integrated junction box by using different lead-out wires, wherein one is the positive and negative electrodes of the cadmium telluride cell, and the other is the positive and negative electrodes of the crystalline silicon cell, the wires between the modules are connected in a plug-in mode by using matching male and female heads, and the wiring cables of the cadmium telluride and the crystalline silicon use different colors and the wiring male and female heads use different sizes, so as to distinguish the cell wiring of different modules.

[0027] S8: testing and passing to complete the cadmium telluride / crystalline silicon laminated solar cell module. Example 1

[0028] A cadmium telluride / TOPCon cell photovoltaic module is used, a 19.5% cadmium telluride cell module is selected, a TOPCon cell piece with a size of 182.2mm*183.75mm is selected, the photoelectric conversion efficiency is 25%, a 72-piece half-piece photovoltaic module version is used, the module size is 2278mm*1134mm*30mm, the conversion efficiency of the tested photovoltaic module is 27.5%, under the STC (AM1.5) test condition, the output power of the photovoltaic module is 710W. Example 2

[0029] CdTe / TOPCon PV module, 19% CdTe cell module is selected, and the size of the TOPCon cell is 210 mm*210 mm, the photoelectric conversion efficiency is 25.2%, then 66 half pieces of PV module version are adopted, the size of the module is 2382 mm*1300 mm*35 mm, then the conversion efficiency of the tested PV module is 27.5%, under the test condition of STC (AM1.5), the output power of the PV module is 850 W. Example 3

[0030] CdTe / TOPCon PV module, 19% CdTe cell module is selected, and the size of the TOPCon cell is 210 mm*210 mm, the photoelectric conversion efficiency is 25.2%, then 66 half pieces of PV module version are adopted, the size of the module is 2382 mm*1300 mm*35 mm, then the conversion efficiency of the tested PV module is 27.5%, under the test condition of STC (AM1.5), the output power of the PV module is 850 W. Example 4

[0031] CdTe / HJT PV module, 19% CdTe cell module is selected, and the size of the HJT cell is 210 mm*210 mm, the photoelectric conversion efficiency is 25.6%, then 66 half pieces of PV module version are adopted, the size of the module is 2382 mm*1300 mm*35 mm, then the conversion efficiency of the tested PV module is 28.2%, under the test condition of STC (AM1.5), the output power of the PV module is 870 W. Example 5

[0032] CdTe / XBC PV module, 19% CdTe cell module is selected, and the size of the XBC cell is 182.2 mm*183.75 mm, the photoelectric conversion efficiency is 26%, then 72 half pieces of PV module version are adopted, the size of the module is 2278 mm*1134 mm*30 mm, then the conversion efficiency of the tested PV module is 29%, under the test condition of STC (AM1.5), the output power of the PV module is 750 W. Example 6

[0033] The cadmium telluride / PERT battery photovoltaic module is selected, 19% cadmium telluride battery module is selected, the size of the PERT battery piece is 182.2mm*183.75mm, the photoelectric conversion efficiency is 24.8%, then the photovoltaic module version of 72 pieces of half pieces is adopted, the module size is 2278mm*1134mm*30mm, and the conversion efficiency of the test photovoltaic module is 27%, under the STC (AM1.5) test condition, the output power of the photovoltaic module is 700W.

[0034] In conclusion, the output power of the cadmium telluride / crystalline silicon laminated solar cell module provided by the application can reach 700W to 870W, the photoelectric conversion efficiency is greatly improved, the decay rates of the above four embodiments under the damp heat test (85℃ / 85%RH) are all <1% / year, and the stability problem of the cadmium telluride / crystalline silicon laminated photovoltaic module is effectively solved.

[0035] It is obvious for those skilled in the art that the application is not limited to the details of the above exemplary embodiments, and the application can be realized in other specific forms without departing from the spirit or essential characteristics of the application. Therefore, the embodiments should be regarded as exemplary and non-limiting, the scope of the application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the application. Any reference signs in the claims should not be regarded as limiting the involved claims.

[0036] Although the embodiments of the application have been shown and described, it is understood by those skilled in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirit of the application, the scope of the application is defined by the appended claims and their equivalents.

Claims

1. A cadmium telluride / crystalline silicon tandem solar cell module, characterized in that: It includes cadmium telluride batteries and crystalline silicon batteries. The front surface is TCO glass (1) on which n-type cadmium sulfide / p-type cadmium telluride heterojunction batteries (2) are deposited. The first encapsulant layer (3), the crystalline silicon battery layer (5), the second encapsulant layer (6), the backplate glass (7), and the integrated junction box (8) are stacked in sequence.

2. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: The cadmium telluride battery and the crystalline silicon battery are mechanically stacked and interconnected.

3. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: The first adhesive layer (3) and the second adhesive layer (6) are POE or PVB adhesive films.

4. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: It also includes a high-transmittance, heat-resistant insulating isolation layer (4) between the first adhesive film layer (3) and the crystalline silicon battery layer (5), wherein the high-transmittance, heat-resistant insulating isolation layer (4) is a POE adhesive film or a PVB adhesive film or a POE and / or PVB and / or EVA mixed co-extruded adhesive film with a silica nanoparticle scattering layer incorporated.

5. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: The crystalline silicon cell layer (5) is composed of multiple monocrystalline silicon cells connected in series, specifically PERT, TOPCon, HJT or XBC cells.

6. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: Cadmium telluride and crystalline silicon use a dual-circuit independent output design, and only interconnections of the same type of battery circuits are allowed between the components.

7. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: The back glass (7) is an ultra-thin grid-coated back glass, an ultra-thin chemically tempered glass, or a patterned ultra-thin glass.

8. The cadmium telluride / crystalline silicon tandem solar cell module according to claim 1, characterized in that: The system adopts an integrated junction box design. The cadmium telluride (CdT) sub-cell strings and crystalline silicon (CSI) sub-cell strings are connected to the integrated junction box with different lead wires. The junction box has two lead wires: one for the positive and negative terminals of the CdT cells and the other for the positive and negative terminals of the CSI cells. The wires between the modules are connected by matching male and female connectors in a plug-in manner. The wiring cables for CdT and CSI cells use different colors and the male and female connectors use different sizes to distinguish the battery wiring of different modules.

9. A method for preparing the cadmium telluride / crystalline silicon tandem solar cell of claim 1, comprising the following steps: S1: Define electrodes by laser scribing on transparent conductive glass (TCO glass); S2: The core device layer of cadmium telluride solar cells, which grows N-type cadmium sulfide and P-type cadmium telluride as well as a carrier transport layer, and then defines sub-cells using laser scribing; S3: Deposit electrode material, then define the electrode using laser scribing; S4: Use a laser to create isolation lines along the edge of the TCO glass; S5: Use a welding machine to connect the busbar and the positive and negative leads of the cadmium telluride sub-cell connected in series; S6: The TCO glass of the cadmium telluride battery module is used as the front glass of the crystalline silicon photovoltaic module. The conventional crystalline silicon photovoltaic module production process is adopted. POE or PVB or POE or PVB or EVA or even a mixture of multiple co-extruded films with silica nanoparticle scattering layer are applied to the TCO glass. A high-transmittance heat-resistant separator is applied or directly applied to the crystalline silicon battery cell string. Then the positive and negative busbars of the crystalline silicon battery string are welded, the above-mentioned film is applied, and finally the back glass is applied. After lamination, the edges are removed, glue is applied, and the frame is installed. S7: The cadmium telluride sub-cell strings and the crystalline silicon sub-cell strings are connected to the integrated junction box with different lead wires. One lead wire is the positive and negative terminals of the cadmium telluride battery, and the other is the positive and negative terminals of the crystalline silicon battery. The wires between the modules are connected by matching male and female connectors. The wiring cables of cadmium telluride and crystalline silicon use different colors and different sizes of male and female connectors to distinguish the battery wiring of different modules. S8: Passing the test completes the cadmium telluride / crystalline silicon tandem solar cell module.

Images