阅读说明：本技术 一种钙钛矿与n型硅基背接触电池叠加电池结构 (Perovskite and silicon-based back of body contact battery stack battery structure of N type ) 是由 张敏 刘飞 何凤琴 王冬冬 张志郢 常纪鹏 于 2019-08-30 设计创作，主要内容包括：本发明公开了一种钙钛矿与N型硅基背接触电池叠加电池结构,其特征在于,依次包括：钙钛矿材料吸收层、正面透明导电膜沉积层、正面钝化层、前表面场、N型单晶硅片衬底及背面钝化层,N型单晶硅片衬底与背面钝化层之间设有相互独立的背面P+掺杂层和背面N+掺杂层,两个金属电极。分别与背面P+掺杂层、背面N+掺杂层连接,且从背面钝化层表面露出。本发明采用丝网印刷纳米磷浆料或纳米硼浆料叠加激光推进的方式实现钙钛矿材料叠加背接触电池背面叉指状PN结的制备,实现叠层电池内部电流的最大输出,进一步提高背接触太阳电池的光电转换效率。(The invention discloses a perovskite and N-type silicon-based back contact battery superposed battery structure which is characterized by sequentially comprising the following components: the solar cell comprises a perovskite material absorption layer, a front transparent conductive film deposition layer, a front passivation layer, a front surface field, an N-type monocrystalline silicon wafer substrate and a back passivation layer, wherein a back P + doped layer and a back N + doped layer which are independent of each other are arranged between the N-type monocrystalline silicon wafer substrate and the back passivation layer, and two metal electrodes are arranged between the N-type monocrystalline silicon wafer substrate and the back passivation layer. And the back surface P + doped layer and the back surface N + doped layer are respectively connected and exposed out of the surface of the back surface passivation layer. According to the invention, the preparation of the interdigital PN junction on the back surface of the perovskite material superposed back contact cell is realized by adopting a screen printing nano phosphorus slurry or nano boron slurry superposed laser propulsion mode, the maximum output of the current in the laminated cell is realized, and the photoelectric conversion efficiency of the back contact solar cell is further improved.)

1. The utility model provides a perovskite and silicon-based back of body contact battery stack battery structure of N type which characterized in that includes in proper order: the solar cell comprises a perovskite material absorption layer (1), a front transparent conductive film deposition layer (2), a front passivation layer (3), a front surface field (4), an N-type monocrystalline silicon wafer substrate (5) and a back passivation layer (8), wherein a back P + doped layer (6) and a back N + doped layer (7) which are independent of each other are arranged between the N-type monocrystalline silicon wafer substrate (5) and the back passivation layer (8), and the two metal electrodes are arranged. (9) Are respectively connected with the back P + doped layer (6) and the back N + doped layer (7) and are exposed from the surface of the back passivation layer (8).

2. The perovskite and N-type silicon-based back contact cell stacked cell structure of claim 1, wherein the front passivation layer (3) and the back passivation layer (8) are both SiO₂A layer; the front transparent conductive film deposition layer (2) is an ITO conductive film layer.

Technical Field

The invention relates to a perovskite and N-type silicon-based back contact cell superposed cell structure, and belongs to the technical field of solar cells.

Background

At present, silicon-based solar cells are the mainstream of solar cells, occupy 90% of the photovoltaic market, the efficiency of silicon solar cells reaches 26.1%, and is close to the ultimate efficiency (29.4%) of shackley-quineser (Shockley-Queisser), but the manufacturing cost is higher than that of petroleum and nuclear energy sources, so that the reduction of the preparation cost of silicon-based solar cells is still the research and development target in the implementation stage and in the future. It has been found that because of the broad energy distribution of the solar spectrum, any semiconductor material can only absorb photons with energy values greater than its forbidden bandwidth. Therefore, the laminated cell can be formed by superposing the wide band gap material on the top layer of the silicon cell, the spectral response of the cell is widened, the solar energy is utilized to the maximum extent, and the efficiency of the solar cell is improved. The theoretical ultimate efficiency of the silicon-based laminate cell, which has been reported at present, can be improved from 29% to 42.5%. Perovskite materials are also considered as light absorbing materials for the next generation of low cost solar cells. Since the perovskite and the silicon have different band gaps, in order to fully utilize the solar spectrum, the perovskite solar cell can be used as a top cell to form a laminated solar cell with a silicon cell, so that the spectral response range of the cell is widened, the efficiency of the solar cell is improved, and the preparation cost is reduced.

With the continuous innovation of battery technology, the excellent performance of perovskite materials becomes a popular research object, and according to the report of the international photovoltaic technology progress route, the battery share of a novel structure reaches about 5 percent and becomes an important photovoltaic power generation technical form by 2025 years; the perovskite battery is praised as a technical direction for realizing revolutionary improvement on a photovoltaic technology in the future, the production cost of the photovoltaic battery can be greatly reduced, and the electricity consumption cost is saved, and is evaluated as one of 10 scientific breakthroughs in 2013 by the journal of Science; is praised as a high-efficiency battery technical form which is hopeful to bring subversive innovation to energy development in the existing high-efficiency photovoltaic technology, and the industrialized large-area perovskite N-type silicon-based laminated battery becomes a research hotspot. How to exert the excellent characteristics of the laminated battery to the maximum extent, prepare the PN junction with excellent quality, realize the maximum output of current and further reduce the cost of the laminated battery is also the key technical point at present. The patent provides a preparation method of a large-area perovskite N-type silicon-based laminated battery, and particularly provides a preparation method of a PN junction of the battery with the structure. Therefore, the current is effectively led out, and the photoelectric conversion efficiency of the battery is maximized.

In recent years, the N-type silicon substrate high-efficiency cell is rapidly developed, and the market advantage is more obvious, however, the material characteristics of the silicon substrate material determine that the silicon substrate material has a narrow spectral absorption range, and the comprehensive absorption of the solar spectrum cannot be realized to the maximum extent. However, perovskite materials have a wide spectral absorption range, and a laminated battery with the perovskite materials superposed with an N-type silicon-based structure is produced. Although the laminated cell can realize effective absorption of solar spectrum and generate more current, the cell still has internal loss in the output process, and meanwhile, the conventional tubular high-temperature diffusion mode for preparing the PN junction has large damage to a silicon wafer substrate, poorer sheet resistance uniformity and general PN junction performance; meanwhile, the electric energy consumption at high temperature is large, and the cost of the battery is high according to the old age. Therefore, the invention provides a method for preparing a PN junction of a perovskite-stacked N-type silicon-based laminated battery, which is started from how to realize the optimal output of the current in the battery and reduce the manufacturing cost of the battery, so that the PN junction with excellent performance is prepared, and the maximum output of the current in the laminated battery is realized.

Researches report that the spectral response of the perovskite material has very high spectral absorption capacity in the ultraviolet band of 300-400nm, and the spectral absorption capacity reaches the highest in the spectral range of 400-700 nm. However, the N-type silicon-based battery has the problem of narrow absorption spectrum band. Therefore, a plurality of scholars provide a laminated cell structure of the perovskite thin film layer laminated silicon-based cell, and the problem that the silicon-based solar cell cannot fully utilize light is solved, so that more light can be absorbed in unit area, and the photoelectric conversion efficiency of the silicon-based cell is effectively improved.

The development of perovskite and silicon-based laminated battery technology becomes one of the high-efficiency battery technology suggestions at present. How to realize the preparation of the large-area perovskite silicon-based laminated cell and exert the greatest advantages of the laminated cell becomes the key field of the research and development of the prior art. The preparation method reported for the perovskite and N-type silicon-based laminated cell at present mainly adopts a boron tribromide tubular high-temperature diffusion mode to realize the preparation of the PN junction of the laminated cell, in the preparation process, the high-temperature diffusion mode can cause damage to a silicon wafer substrate, meanwhile, as the boiling point of boron oxide is as high as 1680 ℃, and the boron diffusion temperature is generally lower than 1000 ℃, the boron oxide is still in a liquid state at the temperature, and is difficult to be uniformly distributed on the surface of the silicon wafer, so that the borosilicate glass generated by the reaction is not uniform, and the specific expression is that the color distribution of the surface of the silicon wafer after diffusion is not uniform, and the phenomenon of 'flower pieces' is formed. Therefore, when the technology is adopted to realize the preparation of the PN junction, the diffusion uniformity is difficult to ensure, and the quality of the PN junction is relatively poor. For an N-type laminated cell with an N-type silicon wafer substrate and a perovskite superposed thereon, how to form a high-quality PN junction on the N-type silicon wafer substrate is particularly important for providing a higher-quality channel for the current output of the laminated cell, and becomes a key point for the research and development of the large-area perovskite superposed N-type silicon-based laminated cell technology. Therefore, the project provides a technical implementation mode of boron diffusion of silk-screen printing nanometer boron paste superposition laser doping. The preparation of the high-quality PN junction is realized on the N-type silicon substrate, so that the output of the excellent optical property and electrical property of the perovskite thin film layer is ensured.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the current tubular high-temperature boron diffusion has the problems of uneven sheet resistance and poor PN junction quality, which causes the current output loss of the battery.

In order to solve the above problems, the present invention provides a perovskite and N-type silicon-based back contact cell stacked cell structure, which is characterized by sequentially comprising: the solar cell comprises a perovskite material absorption layer, a front transparent conductive film deposition layer, a front passivation layer, a front surface field, an N-type monocrystalline silicon wafer substrate and a back passivation layer, wherein a back P + doped layer and a back N + doped layer which are independent of each other are arranged between the N-type monocrystalline silicon wafer substrate and the back passivation layer, and two metal electrodes are arranged between the N-type monocrystalline silicon wafer substrate and the back passivation layer. And the back surface P + doped layer and the back surface N + doped layer are respectively connected and exposed out of the surface of the back surface passivation layer.

Preferably, the front passivation layer and the back passivation layer are both SiO₂A layer; the front transparent conductive film deposition layer is an ITO conductive film layer.

According to the invention, the preparation of the interdigital PN junction on the back surface of the perovskite material superposed back contact cell is realized by adopting a screen printing nano phosphorus slurry or nano boron slurry superposed laser propulsion mode, the maximum output of the current in the laminated cell is realized, and the photoelectric conversion efficiency of the back contact solar cell is further improved.

Drawings

Fig. 1 is a schematic diagram of a stacked cell structure of a perovskite and N-type silicon-based back contact cell provided by the invention.

Detailed Description

In order to make the invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.