阅读说明：本技术 一种微型聚光太阳能电池及其制备方法 (Miniature concentrating solar cell and preparation method thereof ) 是由 王岚 于 2018-12-28 设计创作，主要内容包括：本发明涉及太阳能电池技术领域,具体涉及一种微型聚光太阳能电池及其制备方法,所述微型聚光太阳能电池包括：衬底、太阳能微电池单元和聚光透镜,所述太阳能微电池单元包括依次设置的背电极、吸收层、缓冲层、窗口层和透明绝缘层；其中所述太阳能微电池单元设置于所述衬底上；所述聚光透镜设置于所述太阳能微电池单元吸收光线的一侧,与所述太阳能微电池单元对应设置。本发明的微型聚光太阳能电池为一体化设计,增加了入射光强,节省了稀有金属用量,提高了电池转换效率。(The invention relates to the technical field of solar cells, in particular to a miniature concentrating solar cell and a preparation method thereof, wherein the miniature concentrating solar cell comprises: the solar micro-battery unit comprises a back electrode, an absorption layer, a buffer layer, a window layer and a transparent insulating layer which are sequentially arranged; wherein the solar microcell unit is disposed on the substrate; the condensing lens is arranged on one side of the solar micro-battery unit, which absorbs light, and is arranged corresponding to the solar micro-battery unit. The miniature concentrating solar cell is integrally designed, so that the incident light intensity is increased, the consumption of rare metals is saved, and the cell conversion efficiency is improved.)

1. A miniature concentrator solar cell, comprising:

a substrate;

the solar micro-battery unit comprises a back electrode, an absorption layer, a buffer layer, a window layer and a transparent insulating layer which are sequentially arranged; wherein the solar microcell unit is disposed on the substrate;

and the condensing lens is arranged on one side of the solar micro-battery unit for absorbing light and corresponds to the solar micro-battery unit.

2. The miniature concentrator solar cell of claim 1, wherein the substrate comprises: the glass substrate is arranged on the metal heat conduction substrate; the back electrode is arranged on the glass substrate;

optionally, the distance between the back electrodes is 1-2 mm, and the back electrode is a layer of Mo deposited on the glass substrate and has a thickness of 500-1000 nm.

3. The miniature concentrator solar cell of claim 1 or 2, wherein said absorber layer is a CIGS absorber layer disposed on said back electrode, said CIGS absorber layer having a thickness of 2-3 μ ι η;

optionally, the buffer layer is an n-type buffer layer; the thickness of the buffer layer is 30-50 nm.

4. The miniature concentrator solar cell of any one of claims 1-3, wherein the window layer comprises a transparent high resistance layer and a transparent conductive layer; the transparent high-resistance layer is made of intrinsic zinc oxide and aluminum oxide; the transparent conducting layer is made of one of aluminum-doped zinc oxide, tin-doped indium oxide and antimony-doped tin oxide; the thickness of the window layer is 500-1000 nm;

optionally, the transparent insulating layer is disposed in a gap between the substrate, the solar micro-battery unit and the condenser lens, and the transparent insulating layer is made of a transparent electrical insulating material and is used for supporting the condenser lens and insulating and isolating the condenser lens from the solar micro-battery unit.

5. The micro concentrator solar cell of any of claims 1-4, wherein the diameter of the concentrator lens is equal to or greater than the pitch between the solar microcell units; the diameter of the condensing lens is 1.8-2.2 mm, and the refractive index is 1.5-2.5.

6. The miniature concentrator solar cell of any of claims 1-5, comprising a plurality of solar microcell units arranged in a rectangular array,

optionally, the width of the solar microbattery cell is 50-100 μm.

7. A method for manufacturing a miniature concentrator solar cell as claimed in any one of claims 1 to 6, comprising the steps of:

s1, preparing a solar micro-battery unit on a substrate, and arranging a current grid line on a back electrode of the solar micro-battery unit;

and S2, arranging a condensing lens on the solar micro battery unit.

8. The method for manufacturing a solar microcell unit according to claim 7, wherein the step of manufacturing a solar microcell unit on a substrate in S1 is: forming a back electrode on a substrate; and the back electrode is sequentially provided with an absorption layer, a buffer layer, a window layer and a transparent insulating layer.

9. The method of claim 8, wherein the absorber layer is deposited on the back electrode using a selective deposition method;

the selective deposition method is a PVD method with a mask plate, an electrodeposition method or a printing method.

10. The preparation method of claim 9, wherein the absorption layer is deposited by depositing indium particles on the back electrode, sequentially depositing copper and gallium on the indium particles, and selenizing to obtain the absorption layer;

the particle size of the indium particles is 50-100 mu m.

Technical Field

The invention relates to the technical field of solar cells, in particular to a miniature concentrating solar cell and a preparation method thereof.

Background

In recent years, thin film solar cells have become a development trend in the photovoltaic industry, and have the advantages of saving materials, improving production rate, reducing transportation cost and the like. The Copper Indium Gallium Selenide (CIGS) thin film battery has the advantages of high light absorption coefficient, high conversion efficiency, high stability, radiation resistance, adjustable forbidden bandwidth and the like, the highest efficiency can reach 22.9%, and the Copper Indium Gallium Selenide (CIGS) thin film battery has a very good application prospect. However, indium and gallium in the CIGS thin film battery belong to rare metals, have low earth reserves and are expensive, and the large-scale production of the CIGS battery is severely restricted. Therefore, saving as much as possible the material needed to produce a CIGS absorber is an important research topic in the industry.

At present, the main method for saving the material of the absorption layer is to prepare an ultra-thin absorption layer, i.e. to reduce the thickness of the absorption layer in the vertical direction, as is well known, the thickness of the absorption layer of the traditional thin film CIGS solar cell is 2-3 μm, while the thickness of the absorption layer of the ultra-thin CIGS solar cell aiming at saving the material of the absorption layer is less than 1 μm. However, the ultrathin CIGS solar cell is low in quantum efficiency, weak in solar spectrum absorption capacity, especially greatly reduced in long-wave band absorption capacity, low in short-circuit current density and low in cell conversion efficiency; in addition, the carrier recombination rate at the interface of the back electrode and the absorption layer is increased, resulting in a decrease in the open circuit voltage and fill factor of the battery.

Disclosure of Invention

Therefore, the technical problem to be solved by the present invention is to overcome the defect of the prior art that the reduction of the thickness of the absorption layer causes the reduction of the conversion efficiency of the cell, thereby providing a micro concentrating solar cell with reduced absorption layer material in the horizontal direction and a method for preparing the same.

Therefore, the technical scheme of the invention is as follows:

a miniature concentrator solar cell, comprising:

a substrate;

the solar micro-battery unit comprises a back electrode, an absorption layer, a buffer layer, a window layer and a transparent insulating layer which are sequentially arranged; wherein the solar microcell unit is disposed on the substrate;

and the condensing lens is arranged on one side of the solar micro-battery unit for absorbing light and corresponds to the solar micro-battery unit.

Optionally, the substrate comprises: the glass substrate is arranged on the metal heat conduction substrate; the back electrode is disposed on the glass substrate.

Optionally, the distance between the back electrodes is 1-2 mm, and the back electrode is a layer of Mo deposited on the glass substrate and has a thickness of 500-1000 nm.

Optionally, the absorbing layer is a CIGS absorbing layer, is arranged on the back electrode, and has a thickness of 2-3 μm;

the buffer layer is an n-type buffer layer, and the buffer layer is made of CdS and In₂S₃Or Zn (O, S); the thickness of the buffer layer is 30-50 nm.

Optionally, the window layer comprises a transparent high-resistance layer and a transparent conductive layer; the transparent high-resistance layer is made of intrinsic zinc oxide or aluminum oxide; the transparent conducting layer is made of one of aluminum-doped zinc oxide, tin-doped indium oxide and antimony-doped tin oxide; the thickness of the window layer is 500-1000 nm; the thickness of the transparent high-resistance layer is 40-60 nm.

The transparent insulating layer is arranged in a gap among the substrate, the solar micro-battery unit and the condenser lens, is made of a transparent electric insulating material and is used for supporting the condenser lens and insulating and isolating the condenser lens from the solar micro-battery unit.

Optionally, the diameter of the condenser lens is larger than or equal to the distance between the solar micro-battery units; the diameter of the condensing lens is 1.8-2.2 mm, and the refractive index is 1.5-2.5. Preferably, the diameter of the condenser lens is 2 mm. Preferably, the refractive index of the condenser lens is 1.5.

Optionally, the micro concentrating solar cell comprises a plurality of solar micro battery cells arranged in a rectangular array.

Optionally, the width of the solar microbattery cell is 50-100 μm.

Optionally, the condensing lenses are provided in number and correspond to the solar micro-battery units one by one.

Optionally, the substrate material is selected from glass, stainless steel or polyimide.

Optionally, the condenser lens is a convex lens.

Optionally, the back electrode of the solar micro-battery unit is metal molybdenum with a thickness of 0.5-1 μm.

Optionally, the transparent insulating layer material of the solar micro-battery unit is silicon dioxide, and the thickness is 1500-.

The invention also provides a preparation method of the miniature concentrating solar cell, which comprises the following steps:

s1, preparing a solar micro-battery unit on a substrate, and arranging a current grid line on a back electrode of the solar micro-battery unit;

and S2, arranging a condensing lens on the solar micro battery unit.

Preferably, the step of preparing the solar micro-battery cell on the substrate in S1 is: forming a back electrode on a substrate, wherein the back electrode is a rectangular array; and the back electrode is sequentially provided with an absorption layer, a buffer layer, a window layer and a transparent insulating layer.

Preferably, the absorption layer is deposited on the back electrode by using a selective deposition method;

the selective deposition method is a PVD method with a mask plate, an electrodeposition method or a printing method.

Preferably, the absorption layer is deposited by depositing indium particles on the back electrode, sequentially depositing copper and gallium on the indium particles, and then selenizing to obtain the absorption layer;

the particle size of the indium particles is 50-100 mu m.

The technical scheme of the invention has the following advantages:

1. the invention provides a miniature concentrating solar cell, which comprises a substrate; the solar micro-battery unit comprises a back electrode, an absorption layer, a buffer layer, a window layer and a transparent insulating layer which are sequentially arranged, wherein the back electrode is arranged on the substrate; and the condensing lens is arranged on one side of the solar micro-battery unit for absorbing light and corresponds to the solar micro-battery unit. The focusing function of the condensing lens can greatly improve the incident light intensity and increase the light absorption of the solar micro-battery unit, thereby improving the short-circuit current and the open-circuit voltage and increasing the battery conversion efficiency; the rectangular array of the solar micro-battery units reduces the consumption of materials required in the horizontal direction on the basis of the existing thin-film solar battery, thereby greatly saving the cost; although the incident light intensity is increased by the condenser lens, the temperature of the battery is higher, and the micro battery unit with a small area can dissipate the gathered heat as soon as possible, so that the passive cooling effect is directly achieved; and the condensing lens is integrated into the battery device, and the integrated design saves peripheral materials, is simple and easy to install and saves cost.

2. According to the miniature concentrating solar cell provided by the invention, the plurality of concentrating lenses are arranged and correspond to the solar micro-cell units one by one. The arrangement can ensure that the efficiency of each solar micro-battery unit is consistent, and avoid the conditions of different unit efficiencies and different material consumptions caused by uneven light intensity in unit area.

3. According to the micro concentrating solar cell provided by the invention, the forming method of the absorption layer adopts a selective deposition method, the bottom-up preparation method saves materials compared with the traditional top-down method, and the deposition amount of the materials in each step can be strictly controlled by a method of depositing indium, copper and gallium step by step and then selenizing, so that the content of each element in the film layer can be accurately controlled.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic view of a micro concentrating solar cell according to the present invention;

FIG. 2 is a schematic diagram of the rectangular array arrangement of the solar micro-battery unit according to the present invention;

FIG. 3 is an I-V plot of a solar cell;

the reference numbers in the figures denote: the solar micro-battery comprises a solar micro-battery unit rectangular array, a substrate 2, a back electrode 3, an absorption layer 4, a buffer layer 5, a transparent high-resistance layer 6, a transparent conducting layer 7, a transparent insulating layer 8, a transparent electric insulating material 9 and a condensing lens 10.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the solar cell and the method for manufacturing the same according to the present invention are further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.

As shown in fig. 1, it is a schematic view of the structure of the micro concentrating solar cell of the present invention; the method comprises the following steps:

a substrate 2;

the solar micro-battery unit comprises a back electrode 3, an absorption layer 4, a buffer layer 5, a window layer and a transparent insulating layer 8 which are sequentially arranged; wherein the solar micro-battery unit is arranged on the substrate 2;

and the condensing lens 10 is arranged on one side of the solar micro-battery unit, which absorbs light, and is arranged corresponding to the solar micro-battery unit.

The focusing function of the condensing lens 10 can greatly improve the incident light intensity and increase the light absorption of the solar micro-battery unit, thereby improving the short-circuit current and the open-circuit voltage and increasing the battery conversion efficiency; the solar micro-battery units are arranged in a plurality and are distributed on the substrate at intervals. The solar micro-battery units are distributed in a rectangular array mode. The rectangular array 1 of the solar micro-battery unit reduces the consumption of materials required in the horizontal direction on the basis of the existing thin-film solar battery, thereby greatly saving the cost; although the incident light intensity is increased by the condenser lens 10, the battery temperature is higher, and the micro battery unit with a small area can dissipate the gathered heat as soon as possible, so that the passive cooling effect is directly achieved; and the condenser lens 10 is integrated into the battery device, the integrated design saves peripheral materials, is simple and easy to install, and saves cost. The diameter of the condensing lens is larger than or equal to the distance between the solar micro-battery units; the width of the solar micro-battery unit is 50-100 mu m. The plurality of condensing lenses are arranged and correspond to the solar micro-battery units one by one. The setting can ensure that one solar micro-battery unit corresponds to one condensing lens 10, thereby ensuring that the efficiency of each solar micro-battery unit is consistent, and avoiding the conditions of different unit efficiencies and different material consumptions caused by uneven light intensity in unit area. The gaps of the substrate 2, the solar microcell unit and the condenser lens 10 are filled with a transparent electrically insulating material 9. The transparent electric insulating material 9 is used for supporting the condensing lens 10, insulating and isolating the condensing lens from the solar micro-battery unit, and is matched with the condensing lens 10, so that the light reaching the absorption layer is the maximum light intensity of a light path focusing point. The material of the condensing lens is not specifically limited, and may be arbitrarily selected as long as the effect of the present invention is not damaged, for example, materials with different optical refractive indexes may be selected to match with the transparent insulating layer to facilitate focusing of the optical path, the size of the condensing lens and the distance to the solar micro battery unit may be adjusted within a certain range to achieve the optimal focusing effect of the optical path, and optionally, the distance from the condensing lens to the solar micro battery unit is 1.5 to 2 mm. The condensing lens 10 is a convex lens, the refractive index of the condensing lens 10 is 1.5-2.5, and preferably, the refractive index of the condensing lens 10 is 1.5. The diameter of the condenser lens is 1.8-2.2 mm, and preferably, the diameter of the condenser lens is 2 mm.

The substrate 2 of the present invention includes: the glass substrate is arranged on the metal heat conduction substrate; the back electrode is disposed on the glass substrate. The material of the substrate 2 is not particularly limited and may be arbitrarily selected as long as the effects of the present invention are not impaired; preferably, the substrate 2 material is selected from glass, stainless steel or polyimide; preferably, the metal heat conducting substrate is copper or other excellent heat conductor, and the thickness is 1-2 mm. The material of the back electrode 3 of the solar microcell unit of the present invention is not particularly limited, and may be arbitrarily selected as long as the effects of the present invention are not impaired; preferably, the back electrode 3 of the solar microbattery unit is made of molybdenum with a thickness of 0.5-1 μm, preferably usingDepositing by a magnetron sputtering method; preferably, the method further comprises the step of ablating the surface of the molybdenum by laser to pattern the molybdenum so as to form a strip-shaped structure; the distance between the back electrodes is 1-2 mm. The absorption layer 4 of the solar micro-battery unit is a CIGS absorption layer, and the thickness is 2-3 mu m. The buffer layer 5 of the solar micro-battery unit is an n-type buffer layer made of cadmium sulfide and In₂S₃Or Zn (O, S) with a thickness of 30-50 nm. The preparation method of the buffer layer is not particularly limited. Preferably, the buffer layer can be prepared by a chemical water bath deposition method. The thickness of the window layer of the solar micro-battery unit is 500-1000 nm, and the window layer comprises a transparent high-resistance layer 6 and a transparent conducting layer 7; the transparent high-resistance layer 6 is made of intrinsic zinc oxide or aluminum oxide and has the thickness of 40-60 nm; the transparent conductive layer 7 is made of one of aluminum-doped zinc oxide, tin-doped indium oxide and antimony-doped tin oxide. The preparation method of the window layer is not particularly limited, and the window layer is preferably obtained by deposition by a magnetron sputtering method. The transparent insulating layer 8 is made of silicon dioxide and has a thickness of 1500-2000 μm. Preferably, the transparent electrically insulating material 9 is identical to the transparent insulating layer 8 material.

The invention also provides a preparation method of the miniature concentrating solar cell, which comprises the following steps:

s1, preparing a solar micro-battery unit on a substrate 2, and arranging a current grid line on a back electrode 3 of the solar micro-battery unit;

and S2, arranging a condensing lens 10 on the solar micro battery unit.

Wherein the step of preparing the solar microcell unit on the substrate 2 in S1 is: forming a back electrode 3 on a substrate 2, wherein the back electrode 3 is a rectangular array; an absorption layer 4, a buffer layer 5, a window layer and a transparent insulating layer 8 are sequentially formed on the back electrode 3.

The forming method of the absorption layer 4 is a selective deposition method; compared with the traditional top-down method, the bottom-up preparation method saves materials, and can strictly control the deposition amount of the materials in each step by the method of depositing indium, copper and gallium step by step and then selenizing, thereby accurately controlling the content of each element of the film layer.

The selective deposition method is a PVD method with a mask plate, an electrodeposition method or a printing method. Preferably, the deposition method of the absorption layer 4 is to deposit indium particles on the back electrode 3, sequentially deposit copper and gallium on the indium particles, and then selenize to obtain the absorption layer 4. Preferably, the indium particles have a particle size of 50 to 100 μm.