Laminated solar cell

Abstract

The utility model relates to a laminated solar cell. The laminated solar cell comprises a first band-gap solar cell, a second band-gap solar cell and an insulation conversion layer, the first band-gap solar cell comprises a wide band-gap solar cell, the second band-gap solar cell comprises a narrow band-gap solar cell, and the insulation conversion layer is arranged between the first band-gap solar cell and the second band-gap solar cell. The insulation conversion layer is arranged between the first band-gap solar cell and the second band-gap solar cell, insulates the first band-gap solar cell and the second band-gap solar cell, excites high-energy light by low-energy light penetrating through the first band-gap solar cell, and can improve light transmission; and the photoelectric conversion efficiency of the laminated cell system is improved.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a stacked solar cell. Background Art

[0002] Single-junction perovskite solar cells are approaching the theoretical Shockley-Queisser (SQ) efficiency limit, achieving a maximum photoelectric conversion efficiency of nearly 26%. In order to further improve its photoelectric conversion efficiency, a tandem solar cell is constructed by integrating a wide-bandgap perovskite cell with a second-bandgap solar cell to fully utilize the sunlight spectrum.

[0003] The two-terminal series connection and the four-terminal series connection are the main methods of tandem solar cells. Both have the same theoretical limit photoelectric conversion efficiency. The difference is that the four-terminal series connection does not need to consider the current matching problem. In the prior art, the first bandgap solar cell unit and the second bandgap solar cell are simply mechanically stacked, that is, two battery modules with double-layer glass are mechanically stacked.

[0004] At present, the construction of series-connected stacked solar cells is achieved by simply mechanically stacking two double-glass modules, which results in a large gap between the light-absorbing layers of the two cells, affecting the light transmittance and, in turn, the photoelectric conversion efficiency of the stacked cell system. Utility Model Content

[0005] Based on this, it is necessary to provide a stacked solar cell that can improve the photoelectric conversion efficiency.

[0006] A stacked solar cell, comprising:

[0007] A first bandgap solar cell; wherein the first bandgap solar cell comprises a wide bandgap solar cell;

[0008] A second bandgap solar cell; wherein the second bandgap solar cell comprises a narrow bandgap solar cell;

[0009] The insulating conversion layer is arranged between the first bandgap solar cell and the second bandgap solar cell, and is used to insulate the first bandgap solar cell from the second bandgap solar cell, and is also used to be excited by the low energy light passing through the first bandgap solar cell to generate high energy light.

[0010] In one embodiment, the insulating conversion layer includes: an insulating material layer and a conversion functional material layer, and the insulating material layer and the conversion functional material layer are stacked along the stacking direction of the first bandgap solar cell and the second bandgap solar cell.

[0011] In one embodiment, the insulating material layer includes a material having insulating and light-transmitting properties.

[0012] In one of the embodiments, the insulating material layer includes one of the following insulating materials: POE, PMMA, EVA and epoxy resin.

[0013] In one embodiment, the conversion functional material layer includes: an up-conversion luminescent material that is excited within a preset wavelength range, and is used to be excited by low-energy light within the preset wavelength range to produce high-energy light.

[0014] In one embodiment, the conversion functional material layer further comprises any one or more of the following up-conversion luminescent materials: NaErF4:Ho@NaYF4 nanoparticles, Y2O3:Er 3+ Phosphor, Y2O3:Yb 3+ Phosphor and Yb 3+ -Er 3+ Co-doped β-NaYF4 microcrystals.

[0015] In one embodiment, the thickness of the insulation conversion layer is 0.3 mm to 0.6 mm.

[0016] In one embodiment, the first band gap solar cell comprises any solar cell of a perovskite material having a band gap of 1.6 eV to 2.0 eV.

[0017] In one of the embodiments, the second bandgap solar cell includes any one of the following: a crystalline silicon cell, a copper indium gallium selenide solar cell, a perovskite solar cell, an organic solar cell and a quantum dot solar cell.

[0018] In one embodiment, it also includes:

[0019] A first glass is provided on a side of the first band gap solar cell away from the second band gap solar cell;

[0020] The second glass is arranged on a side of the second band gap solar cell away from the first band gap solar cell.

[0021] The above-mentioned stacked solar cell has an insulating conversion layer disposed between the first bandgap solar cell and the second bandgap solar cell. The insulating conversion layer can convert low-energy light passing through the first bandgap solar cell into high-energy light, so that the second bandgap solar cell absorbs the converted high-energy light, thereby improving the light transmittance and the photoelectric conversion efficiency of the stacked cell system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 is a structural block diagram of a stacked solar cell according to an embodiment;

[0024] Figure 2a for Figure 1 A block diagram of the structure of the insulating conversion layer of the mid-tandem solar cell;

[0025] Figure 2b for Figure 1 A block diagram of the structure of the insulating conversion layer of the mid-tandem solar cell;

[0026] Figure 3 FIG. 4 is a structural block diagram of a stacked solar cell according to an embodiment of the present invention.

[0027] Description of reference numerals:

[0028] A first bandgap solar cell 101, an insulation conversion layer 102, and a second bandgap solar cell 103;

[0029] Insulating material layer 201, conversion functional material layer 202;

[0030] The first glass 301 and the second glass 302 . DETAILED DESCRIPTION

[0031] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0033] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first bandgap solar cell may be referred to as a second bandgap solar cell, and similarly, a second bandgap solar cell may be referred to as a first bandgap solar cell. Both the first bandgap solar cell and the second bandgap solar cell are bandgap solar cells, but they are not the same bandgap solar cell.

[0034] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least part of an element” means part or all of an element.

[0035] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0036] In the prior art, two pieces of glass are placed between two solar cells to separate the two solar cells, which results in a large gap between the light-absorbing layers of the two cells, affecting light transmittance and further affecting the photoelectric conversion efficiency of the stacked cell system.

[0037] like Figure 1 As shown, a stacked solar cell of an embodiment includes: a first bandgap solar cell 101, a second bandgap solar cell 103 and an insulating conversion layer 102, wherein the insulating conversion layer 102 is disposed between the first bandgap solar cell 101 and the second bandgap solar cell 103. The insulating conversion layer 102 is used to insulate the first bandgap solar cell 101 from the second bandgap solar cell 103, and the insulating conversion layer 102 is also used to be excited to high-energy light by low-energy light passing through the first bandgap solar cell 101. The first bandgap solar cell 101 includes a wide-bandgap perovskite solar cell, and the second bandgap solar cell 103 includes a narrow-bandgap solar cell.

[0038] It should be noted that the insulating conversion layer 102 forms an insulating gap between the first bandgap solar cell 101 and the second bandgap solar cell 103. After the sunlight passes through the first bandgap solar cell 101, it is converted into low-energy light. After the insulating conversion layer 102 is excited by the low-energy light, it emits high-energy light, so that the second bandgap solar cell 103 absorbs the high-energy light, which can improve the light transmittance between the two solar cells, thereby improving the photoelectric conversion efficiency of the stacked battery system. Compared with the four-terminal series stacked solar cell of the prior art, the stacked solar cell of this scheme excites the low-energy light that the first bandgap solar cell 101 fails to absorb to emit high-energy light through the insulating conversion layer 102, and absorbs the emitted high-energy light through the second bandgap solar cell 103, which can improve the light absorption of the second bandgap solar cell 103, and at the same time, improve the transmittance of the entire stacked solar cell system, thereby improving the photoelectric conversion efficiency of the entire stacked solar cell system.

[0039] Wide bandgap perovskite solar cells refer to a type of perovskite solar cell with a relatively large bandgap, including perovskite solar cells with a bandgap of more than 1.6eV, and wide bandgap perovskite solar cells can absorb photons with higher energy. Narrow bandgap solar cells refer to a type of solar cell with a relatively small bandgap, and narrow bandgap solar cells can absorb photons with lower energy, and the absorption range of narrow bandgap solar cells is relatively large.

[0040] After sunlight irradiates the first bandgap solar cell 101, the first bandgap solar cell 101 absorbs high-energy light, and low-energy light passes through the first bandgap solar cell 101 and irradiates the insulation conversion layer 102. After being excited by the low-energy light, the insulation conversion layer 102 emits high-energy light within the light absorption range of the second bandgap solar cell 103. After the high-energy light irradiates the second bandgap solar cell 103, the second bandgap solar cell 103 absorbs the emitted high-energy light.

[0041] like Figure 2a and Figure 2b As shown, the insulating conversion layer 102 of an embodiment includes: an insulating material layer 201 and a conversion functional material layer 202, and the insulating material layer 201 and the conversion functional material layer 202 are stacked along the stacking direction of the first bandgap solar cell 101 and the second bandgap solar cell 103.

[0042] It should be noted that the insulating material layer 201 is disposed at one end close to the first bandgap solar cell 101, and the conversion functional material layer 202 is disposed at one end close to the second bandgap solar cell 103. Alternatively, the insulating material layer 201 is disposed at one end close to the second bandgap solar cell 103, and the conversion functional material layer 202 is disposed at one end close to the first bandgap solar cell 101.

[0043] The first bandgap solar cell 101 and the second bandgap solar cell 103 are insulated and isolated by the insulating material layer 201, and the low-energy light of the first bandgap solar cell 101 is irradiated to the coating of the conversion functional material layer 202. After being excited by the light, the coating of the conversion functional material layer 202 emits high-energy light, which can improve the light transmittance and the photoelectric conversion efficiency of the second bandgap solar cell 103, thereby improving the photoelectric conversion efficiency of the stacked battery system.

[0044] In one embodiment, the insulating material layer 201 includes a material having insulating properties and light-transmitting properties.

[0045] It should be noted that the risk of short circuit between the first bandgap solar cell 101 and the second bandgap solar cell 103 can be reduced by insulating the first bandgap solar cell 101 and the second bandgap solar cell 103 using an insulating material.

[0046] If the insulating material layer 201 is arranged at one end close to the first band gap solar cell 101, the low-energy light transmitted through the first band gap solar cell 101 is transmitted through the light-transmitting material; if the insulating material layer 201 is arranged at one end close to the second band gap solar cell 103, the high-energy light emitted by the coating of the conversion functional material layer 202 is transmitted through the light-transmitting material, thereby realizing the required light energy transfer between the stacked solar cells.

[0047] In one embodiment, the insulating material layer 201 includes one of the following insulating materials: POE, PMMA, EVA and epoxy resin.

[0048] It should be noted that the first bandgap solar cell 101 and the second bandgap solar cell 103 are insulated and isolated by an insulating material layer 201 having good light transmittance, such as POE, PMMA, EVA and epoxy resin, and used for the required light energy transfer between the first bandgap solar cell 101 and the second bandgap solar cell 103. It can be applicable to a variety of insulating material layers 201 with good light transmittance, thereby improving the compatibility of the insulation conversion layer 102.

[0049] In one embodiment, the conversion functional material layer 202 includes an up-conversion luminescent material that is excited within a preset wavelength range and is used to be excited by low energy light within the preset wavelength range to generate high energy light.

[0050] It should be noted that the up-conversion luminescent material with excitation in the preset wavelength range can excite high-energy light after being stimulated by low-energy light in the preset wavelength range, and can be stimulated by low-energy light in the preset wavelength range to produce high-energy light. The preset wavelength range includes wavelengths greater than 1500nm, so the up-conversion luminescent material with excitation in the preset wavelength range can include an up-conversion luminescent material with 1500nm excitation, and the up-conversion luminescent material with 1500nm excitation can excite high-energy light after being stimulated by low-energy light in the 1500nm wavelength.

[0051] The conversion functional material layer 202 of an embodiment further includes any one or more of the following up-conversion luminescent materials: NaErF4:Ho@NaYF4 nanoparticles, Y2O3:Er 3+ Phosphor, Y2O3:Yb 3+ Phosphor and Yb 3+ -Er 3+ Co-doped β-NaYF4 microcrystals.

[0052] It should be noted that through NaErF4:Ho@NaYF4 nanoparticles, Y2O3:Er 3+ Phosphor, Y2O3:Yb 3+ Phosphor and Yb 3+ -Er 3+ After one or more conversion functional material layers 202 of the co-doped β-NaYF4 microcrystals are exposed to 1500nm low-energy light, they are excited to emit high-energy light, which can be applied to a variety of up-conversion luminescent materials with 1500nm excitation, thereby improving the compatibility of the conversion functional material layer 202.

[0053] Taking the core-shell structured NaErF4:Ho@NaYF4 nanoparticles as an example, 3+ It acts as both a sensitizer and a luminogen, collecting pump photons at 1530 nm and subsequently promoting 980 nm emission, while Ho 3+ The dopant can also act as an emitter to produce efficient up-converted emission at 1180 nm.

[0054] In one embodiment, the thickness of the insulation conversion layer 102 is 0.3 mm to 0.6 mm.

[0055] It should be noted that the thickness of the insulation conversion layer 102 is set to be relatively thin, which reduces the weight of the entire system, reduces the manufacturing cost, improves the output, and is easy to carry and install.

[0056] The first bandgap solar cell 101 of one embodiment includes any solar cell having a perovskite material with a bandgap of 1.6 eV to 2.0 eV.

[0057] It should be noted that the solar cell with a perovskite material having a band gap of 1.6 eV to 2.0 eV increases the transmittance of low-energy light, so that the second band gap solar cell 103 absorbs more, which can improve the transmittance and make the sunlight absorption more sufficient.

[0058] The chemical formula of the perovskite film of the perovskite solar cell includes: Cs x FA 1-x Pb(I y Br 1-y )3, wherein the x of the first bandgap solar cell 103 of the present solution is in the range of 0.17 to 0.3, and the y is in the range of 0.2 to 0.5. The solar cell using the perovskite material with a bandgap of 1.6 eV or even larger can allow more low-energy light to pass through the perovskite cell to be absorbed by the second bandgap solar cell 103 at the bottom, thereby achieving a wider spectral response and making full use of sunlight.

[0059] In one embodiment, the second bandgap solar cell 103 includes any one of the following: a crystalline silicon cell, a copper indium gallium selenide solar cell, a perovskite solar cell, an organic solar cell, and a quantum dot solar cell.

[0060] It should be noted that by absorbing high-energy light through any of the crystalline silicon cells, copper indium gallium selenide solar cells, perovskite solar cells, organic solar cells and quantum dot solar cells, the compatibility of the entire system can be improved.

[0061] The stacked solar cell of one embodiment further includes: a first glass 301 and a second glass 302, wherein the first glass 301 is disposed on a side of the first bandgap solar cell 101 away from the second bandgap solar cell 103. The second glass 302 is disposed on a side of the second bandgap solar cell 103 away from the first bandgap solar cell 101.

[0062] It should be noted that the first glass 301 is arranged on the side of the first bandgap solar cell 101 away from the second bandgap solar cell 103, and the second glass 302 is arranged on the side of the second bandgap solar cell 103 away from the first bandgap solar cell 101. The entire system forms a double-glass component, which can reduce the number of packaging processes by half.

[0063] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0064] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A stacked solar cell, characterized in that: include: A first bandgap solar cell; wherein the first bandgap solar cell comprises a wide bandgap solar cell; A second bandgap solar cell; wherein the second bandgap solar cell comprises a narrow bandgap solar cell; The insulating conversion layer is arranged between the first bandgap solar cell and the second bandgap solar cell, and is used to insulate the first bandgap solar cell from the second bandgap solar cell, and is also used to be excited by the low energy light passing through the first bandgap solar cell to generate high energy light.

2. The tandem solar cell according to claim 1, characterized in that: The insulating conversion layer comprises: an insulating material layer and a conversion functional material layer, and the insulating material layer and the conversion functional material layer are stacked along a stacking direction of the first bandgap solar cell and the second bandgap solar cell.

3. The tandem solar cell according to claim 2, characterized in that: The insulating material layer includes a material having insulating properties and light transmittance.

4. The stacked solar cell according to claim 2, characterized in that: The conversion functional material layer includes: an up-conversion luminescent material that is excited within a preset wavelength range and is used to be excited by low-energy light within the preset wavelength range to produce high-energy light.

5. The tandem solar cell according to claim 1, characterized in that: The thickness of the insulation conversion layer is comprised between 0.3 mm and 0.6 mm.

6. The tandem solar cell according to claim 1, characterized in that: The first bandgap solar cell includes any solar cell having a perovskite material with a bandgap of 1.6 eV to 2.0 eV.

7. The tandem solar cell according to claim 1, characterized in that: The second bandgap solar cell includes any one of the following: a crystalline silicon cell, a copper indium gallium selenide solar cell, a perovskite solar cell, an organic solar cell and a quantum dot solar cell.

8. The tandem solar cell according to claim 1, characterized in that: Also includes: A first glass is provided on a side of the first band gap solar cell away from the second band gap solar cell; The second glass is arranged on a side of the second band gap solar cell away from the first band gap solar cell.

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