Perovskite solar cell

Abstract

The utility model discloses a perovskite solar cell, including a plurality of series connection's sub -cell, solar cell is divided into center area and edge area along width direction, and edge area symmetrical distribution is in center area both sides, center area contains at least one sub -cell, and the section width is d0, and the current density is J0, edge area contains n sub -cells, and the section width is d1, d2, d3……d respectively n , and the corresponding current density is J1, J2, J3……J n , respectively, each section sub -cell section width satisfies: d0xJ0=d1xJ1=d2xJ2=d3xJ3=……=d n xJ n . The section width design is carried out to the edge area sub -cell, reduces the local current loss caused by the film thickness deviation of edge area, effectively improves the current mismatch problem caused by the uneven edge film thickness, optimizes the current distribution, reduces the short board effect of module edge, promotes the power of module, that is, photoelectric conversion efficiency.

Description

Technical Field

[0001] This utility model belongs to the field of solar cell technology, and in particular relates to a perovskite solar cell. Background Technology

[0002] In existing perovskite photovoltaic module manufacturing, a multi-stage laser scribing process is typically used to divide a continuous perovskite thin film into multiple series-connected sub-cells. These sub-cells are then organically connected in series through internal functional and conductive layers. For example... Figure 1 This is a laser-designed pattern for a traditional perovskite solar cell. Current conventional patterns use cells with equal width for each sub-cell. In small-area perovskite cells, the uniformity of the perovskite light-absorbing layer, as well as other layers such as hole transport layers, electron transport layers, and back electrodes, is not significantly different. The film quality of each sub-cell is similar, resulting in comparable series currents and effective series connection. However, when the area of ​​perovskite cells reaches the square meter level, achieving uniformity in the fabrication of each functional layer becomes difficult. During perovskite coating, factors such as solution surface tension or insufficient liquid supply pressure at the edges due to excessive blade width can cause the film edges to become thinner. Subsequent drying and annealing processes also affect the uniformity of the film edges, resulting in lower currents in the edge sub-cells compared to the central area. The overall module current is limited by the low current at the edges, reducing cell power and photoelectric conversion efficiency.

[0003] Based on the above problems, there is a need to provide a perovskite solar cell that solves the problem of reduced module efficiency caused by uneven edges of the perovskite film. Utility Model Content

[0004] The purpose of this invention is to solve all or part of the above-mentioned problems by providing a perovskite solar cell. This invention features a width-designed sub-cell in the edge region, which reduces local current loss caused by film thickness deviation in the edge region, optimizes current distribution, effectively improves the current mismatch problem caused by uneven film thickness at the edge, reduces the short-board effect at the edge of the module, and improves the power of the module, i.e., the photoelectric conversion efficiency.

[0005] This invention provides a perovskite solar cell comprising multiple sub-cells connected in series. The solar cell is divided into a central region and an edge region along its width, with the edge regions symmetrically distributed on both sides of the central region. The central region contains at least one sub-cell with a section width of d0 and a current density of J0. The edge regions contain n sub-cells with section widths of d1, d2, d3, ..., dn. n The corresponding current densities are J1, J2, J3...J n The width of each sub-cell satisfies: d0×J0=d1×J1=d2×J2=d3×J3=……=dn ×J n By designing the segment width of sub-cells, current mismatch caused by uneven film thickness at the edges can be reduced, the short-board effect can be suppressed, and the current distribution can be optimized, thereby improving the photoelectric conversion efficiency of the module.

[0006] The sub-cell, from bottom to top, comprises a conductive substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and a back electrode. The interlayer synergy achieves efficient photoelectric conversion while maintaining device stability.

[0007] The solar cell is divided into multiple sub-cells by laser scribing, and the sub-cells form a series circuit. The scribing includes: P1 scribing: perpendicularly passing through the conductive substrate; P2 scribing: perpendicularly passing through the hole transport layer, perovskite light-absorbing layer, and electron transport layer sequentially from bottom to top; P3 scribing: perpendicularly passing through the back electrode. This three-step laser scribing precisely divides the functional layers, balancing the series resistance and photoactive area, achieving uniform and efficient output from a large-area perovskite module.

[0008] The P1, P2, and P3 lines are staggered; the P2 line is located to the left or right of the P1 line, offset by 100-500 μm; the P3 line is also located to the left or right of the P2 line, offset by 100-500 μm. This balances process tolerances with effective power generation area, improving module power output.

[0009] The P1 scribing width is 50-70μm; the P2 scribing width is 80-100μm; and the P3 scribing width is 70-90μm. This maximizes the effective power generation area and improves module efficiency and yield.

[0010] The conductive substrate is made of FTO conductive glass, which has excellent light transmittance and low sheet resistance, thus improving the photoelectric conversion efficiency of perovskite solar cells.

[0011] The hole transport layer is a nickel oxide hole transport layer with a thickness of 10-20 nm. It provides efficient hole extraction and transport capabilities; the ultra-thin design ensures high light transmittance while maintaining low resistance, thus optimizing device performance.

[0012] The perovskite light-absorbing layer has a thickness of 300-600nm, which fully absorbs sunlight and increases photocurrent density.

[0013] The electron transport layer includes C 60 Electron transport layer and SnO2 electron transport layer; the C 60 The electron transport layer has a thickness of 10-30 nm, and the SnO2 electron transport layer has a thickness of 10-30 nm. 60 It works synergistically with SnO2 to enhance electron transport.

[0014] The back electrode is made of copper with a thickness of 50-150 nm. It has high conductivity, ensuring efficient electron collection and extraction.

[0015] Compared with the prior art, the beneficial effects of this utility model are: the sub-cell width design in the edge region reduces the local current loss caused by the film thickness deviation in the edge region, effectively improves the current mismatch problem caused by the uneven film thickness at the edge, optimizes the current distribution, reduces the short-board effect at the edge of the module, and improves the power of the perovskite photovoltaic module, i.e., the photoelectric conversion efficiency. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a laser-designed pattern for a traditional perovskite solar cell.

[0018] Figure 2 The laser pattern design drawing of the perovskite solar cell provided by this utility model.

[0019] Figure 3 This is a schematic diagram of the structure of the perovskite solar cell provided by this utility model.

[0020] Figure reference numerals: 1-conductive substrate, 2-hole transport layer, 3-perovskite light-absorbing layer, 4-electron transport layer, 5-back electrode. Detailed Implementation

[0021] The following description and accompanying drawings fully illustrate specific embodiments of the present invention to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, procedural, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Some portions and features of some embodiments may be included in or replace portions and features of other embodiments.

[0022] Example

[0023] This embodiment provides a perovskite solar cell, such as Figure 2As shown, the solar cell includes multiple sub-cells connected in series. The solar cell is divided into a central region and an edge region along its width, with the edge regions symmetrically distributed on both sides of the central region. The central region contains at least one sub-cell with a section width of d0 and a current density of J0. The edge regions contain n sub-cells with section widths of d1, d2, d3…d… n The corresponding current densities are J1, J2, J3...J n The width of each sub-cell satisfies: d0×J0=d1×J1=d2×J2=d3×J3=……=d n ×J n By designing the segment width of the sub-cells, current mismatch caused by uneven film thickness at the edges can be reduced, the bottleneck effect can be suppressed, and the current distribution can be optimized, thereby improving the photoelectric conversion efficiency of solar cells. For example, in a 1.2*2.4m panel design with 200 sub-cells, 5-6 sub-cells on the edges have lower current due to uneven film thickness, which will affect the current of the sub-cells in the center, reducing cell power and photoelectric conversion efficiency. The segment width of the sub-cells in the center is d0, while the segment width of the 5-6 sub-cells in the edge areas is redefined.

[0024] like Figure 3 As shown, the sub-cell, from bottom to top, comprises a conductive substrate 1, a hole transport layer 2, a perovskite light-absorbing layer 3, an electron transport layer 4, and a back electrode 5. The interlayer synergy achieves efficient photoelectric conversion while maintaining the stability of the cell structure. The conductive substrate 1 is made of FTO conductive glass; the hole transport layer 2 is a nickel oxide hole transport layer with a thickness of 10-20 nm; the perovskite light-absorbing layer 3 has a thickness of 300-600 nm; the electron transport layer 2 includes C… 60 Electron transport layer and SnO2 electron transport layer; the C 60 The electron transport layer has a thickness of 10-30 nm, and the SnO2 electron transport layer has a thickness of 10-30 nm; the back electrode 5 is a copper electrode with a thickness of 50-150 nm.

[0025] The solar cell unit is divided into multiple sub-cells by laser scribing, and the sub-cells form a series circuit. The scribing includes: P1 scribing: perpendicularly passing through the conductive substrate 1; P2 scribing: perpendicularly passing through the hole transport layer 2, the perovskite light-absorbing layer 3, and the electron transport layer 4 from bottom to top; P3 scribing: perpendicularly passing through the back electrode 5. This three-step laser scribing precisely divides the functional layers, balancing the series resistance and photoactive area, achieving uniform and efficient output of the large-area perovskite module. The P1, P2, and P3 scribings are staggered to improve the module's power output; the P2 scribing is located to the left or right of the P1 scribing, offset by 100-500 μm; the P3 scribing is also located to the left or right of the P2 scribing, offset by 100-500 μm. The width of the P1 line is 50-70μm; the width of the P2 line is 80-100μm; and the width of the P3 line is 70-90μm. The offset direction of the P2 line relative to the P1 line and the P3 line relative to the P2 line are the same.

[0026] The above-mentioned perovskite solar cells are prepared by the following steps:

[0027] The scribing width of the thin-film solar cell is preset to d0. The currents I0, I1, I2, I3...I2 in the outer edge region of each sub-cell are measured. n The current densities J0, J1, J2, J3...J in the outer edge region of each sub-cell are obtained using the formula J = I / S. n Using the central region current I0 as the operating current, and ensuring series current matching of the components, the current values ​​are I0 = I1 = I2 = I3 = ... = I n , that is, J0*S0=J1*S1=J2*S2=J3*S3=……=J n *S n Since S = L * d, and the sub-cells in the same component have the same length L, we obtain the new segment widths d1, d2, d3...d for each sub-cell. n .

[0028] The cleaned FTO substrate 1 was scribed with a P1 line using an ultraviolet laser, cutting the FTO substrate 1 into several small sections. The width of the sub-cell in the central region is d0, and the widths of the sub-cells in the edge regions are d1, d2, d3...d0, respectively. n .

[0029] Hole transport layer 2, perovskite light-absorbing layer 3 and electron transport layer 4 are sequentially fabricated on an FTO substrate. P2 lines are scribed using a green laser. The position of the P2 lines is offset to the left or right by 100-500 μm from the P1 lines. The width of each section corresponds to the width of the FTO substrate after P1 scribing.

[0030] Back electrode 5 is prepared, and P3 is scribed using an infrared laser. The position of P3 is offset to the left or right by 100-500 μm from the position of P2 scribing, and is offset in the same direction as P2 scribing. The width of each section of P2 corresponds to the width of P2 scribing, thus completing the fabrication of perovskite solar cell.

[0031] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A perovskite solar cell, characterized in that, The solar cell comprises multiple sub-cells connected in series. It is divided into a central region and an edge region along its width, with the edge regions symmetrically distributed on both sides of the central region. The central region contains at least one sub-cell with a section width of d0 and a current density of J0. The edge regions contain n sub-cells with section widths of d1, d2, d3…d… n The corresponding current densities are J1, J2, J3...J n The width of each sub-cell satisfies: d0×J0=d1×J1=d2×J2=d3×J3=……=d n ×J n .

2. The perovskite solar cell according to claim 1, characterized in that, The sub-cell comprises, from bottom to top, a conductive substrate (1), a hole transport layer (2), a perovskite light-absorbing layer (3), an electron transport layer (4), and a back electrode (5).

3. The perovskite solar cell according to claim 2, characterized in that, The solar cell is divided into multiple sub-cells by laser scribing, and the sub-cells form a series circuit; the scribing includes: P1 scribing: perpendicularly passing through the conductive substrate (1); P2 scribing: perpendicularly passing through the hole transport layer (2), perovskite light-absorbing layer (3) and electron transport layer (4) from bottom to top; P3 scribing: perpendicularly passing through the back electrode (5).

4. The perovskite solar cell according to claim 3, characterized in that, The P1 line, the P2 line, and the P3 line are staggered lines; the P2 line is located to the left or right of the P1 line, offset by 100-500μm; the P3 line is located to the left or right of the P2 line, offset by 100-500μm.

5. The perovskite solar cell according to claim 3, characterized in that, The width of the line drawn in section P1 is 50-70 μm; the width of the line drawn in section P2 is 80-100 μm; and the width of the line drawn in section P3 is 70-90 μm.

6. The perovskite solar cell according to claim 2, characterized in that, The conductive substrate (1) is made of FTO conductive glass.

7. The perovskite solar cell according to claim 2, characterized in that, The hole transport layer (2) is a nickel oxide hole transport layer with a thickness of 10-20 nm.

8. The perovskite solar cell according to claim 2, characterized in that, The thickness of the perovskite light-absorbing layer (3) is 300-600 nm.

9. The perovskite solar cell according to claim 2, characterized in that, The electron transport layer (4) includes C 60 Electron transport layer and SnO2 electron transport layer; the C 60 The thickness of the electron transport layer is 10-30 nm, and the thickness of the SnO2 electron transport layer is 10-30 nm.

10. The perovskite solar cell according to claim 2, characterized in that, The back electrode (5) is made of copper and has a thickness of 50-150 nm.

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