Solar battery module

Abstract

To provide a solar battery module having high photoelectric conversion efficiency.SOLUTION: A top module in which a number ntop of top cells 10 are connected in series from a light incident side, and a middle / bottom module in which a number nmb of middle / bottom laminated cells in which a middle cell 12 and a bottom cell 14 are laminated and connected in series are laminated with the middle / bottom module on a light incident side, and the top module and the middle / bottom module are connected in series. A ratio nmb / ntop of the number ntop of the number nmb is configured so that the maximum output operation current JMPP(top) of the top module and the maximum output operation current JMPP(mb) of the middle / bottom module satisfy 2|JMPP(top)-JMPP(mb)| / |JMPP(top)+JMPP(mb)|<0.3.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a solar cell module. [Background technology]

[0002] The use of solar energy is an essential technology for achieving carbon neutrality. Solar power generation using solar cells is already widespread around the world, but it accounts for only a small proportion of total power generation. Therefore, the photoelectric conversion efficiency (η SC ) is required to be improved.

[0003] Photoelectric conversion efficiency of solar cells (η SC The most reliable method to improve the photovoltaic conversion efficiency (η) is the technology of using multiple types of solar cells in a multi-junction configuration. For example, a series triple-junction (3S) module has been proposed, in which three types of solar cells with different bandgaps (top cell, middle cell, bottom cell in order of largest bandgap) are stacked and connected in series, a series double-junction module has been stacked and connected in series with a middle cell and a bottom cell, and a series / parallel triple-junction (3S / P) module has been stacked and connected in parallel with a top module with a top cell connected in series. By configuring such a module, the photovoltaic conversion efficiency (η SC ) can be increased. In addition, by combining these solar cell modules with electrochemical reactors, the conversion efficiency (η STC ) can be increased. (Non-Patent Documents 1 to 3) [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] T. Takeda, et al., J. Appl. Phys. 127, 204503 (2020) [Non-patent document 2] T. Takeda, et al., J. Appl. Phys. 132, 075002 (2022) [Non-patent document 3] M. Yamaguchi, et at., J. Appl. Phys. 129, 240901 (2021) Summary of the Invention [Problem to be solved by the invention]

[0005] Photovoltaic conversion efficiency (η SC To increase the efficiency, a highly efficient top cell using a material with a band gap of approximately 2.2 eV to 2.3 eV is required.

[0006] However, it is generally difficult to fabricate a highly efficient solar cell with a large bandgap. On the other hand, if a solar cell module is constructed using a top cell with a bandgap smaller than the above-mentioned appropriate value, the photoelectric conversion efficiency (η SC ) and the conversion efficiency (η STC ) becomes lower.

[0007] Therefore, the photoelectric conversion efficiency (η SC It is desired to be able to provide a solar cell module with a higher [Means for solving the problem]

[0008] One aspect of the present invention is a solar cell module that combines top, middle, and bottom solar cells each having a different band gap, and includes n top cells arranged from the light incident side. top The number of middle / bottom stacked cells, which are made by stacking the middle cell and the bottom cell in series and connecting them in series, is n mbThe serially connected middle / bottom modules are stacked with the middle / bottom modules on the light incident side, and the top module and the middle / bottom module are serially connected, and the number n top and the number n mb The ratio of n mb / n top is the maximum output operating current J of the top module MPP (top) and the maximum output operating current J of the middle / bottom modules MPP (mb) 2|J MPP (top) -J MPP (mb) | / |J MPP (top) +J MPP (mb) The solar cell module is characterized in that it is set to satisfy |<0.3.

[0009] Here, the band gap E of the top cell g (top) is preferably 1.6 eV or more and 2.4 eV or less.

[0010] The bottom cell is preferably at least one of a crystalline silicon cell, a Cu(In,Ga)Se2 cell, and an organic-inorganic hybrid perovskite cell.

[0011] In addition, when the bottom cell is a crystalline silicon cell, the band gap E g (mid) is the bandgap E of the top cell g (top) 0.30E g (top) It is preferable that the value satisfies +0.88±0.1 eV.

[0012] In addition, when the bottom cell is a Cu(In,Ga)Se2 cell, the band gap E g (mid) is the bandgap E of the top cell g (top)0.31E g (top) It is preferable that the value satisfies +0.86±0.1 eV.

[0013] In addition, when the bottom cell is an organic-inorganic hybrid perovskite cell, the band gap E g (mid) is the bandgap E of the top cell g (top) 0.33E g (top) It is preferable that the value satisfies +0.89±0.1 eV.

[0014] In addition, when the bottom cell is a crystalline silicon cell, the number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.41(E g (top) ) 2 -7.13E g (top) +5.63}×0.75 to {2.41(E g (top) ) 2 -7.13E g (top) It is preferable that the above formula satisfies the above formula {+5.63}×1.25.

[0015] In addition, when the bottom cell is a Cu(In,Ga)Se2 cell, the number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.36(E g (top) ) 2 -6.96E g (top) +5.49}×0.75 to {2.36(E g (top) ) 2 -6.96E g(top) It is preferable that the above formula satisfies {+5.49}×1.25.

[0016] Furthermore, when the bottom cell is an organic-inorganic hybrid perovskite cell, the number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.17(E g (top) ) 2 -6.45E g (top) +5.07}×0.75 to {2.17(E g (top) ) 2 -6.45E g (top) It is preferable that the above formula satisfies {+5.07}×1.25.

[0017] The top cell and the middle cell are preferably organic-inorganic hybrid perovskite cells.

[0018] The top module is preferably an integrated solar cell module formed on a light-transmitting substrate, and the middle / bottom module is preferably an integrated two-series solar cell module formed on a substrate. [Effects of the Invention]

[0019] According to the present invention, the photoelectric conversion efficiency (η SC ) can provide a solar cell module with a higher efficiency than conventional modules. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a conceptual diagram showing the configuration of a solar cell module. [Figure 2] FIG. 10 is a diagram showing the dependence of the conversion efficiency of a three-junction solar cell module using a crystalline silicon cell as the bottom cell on the band gap of the top cell. [Figure 3]FIG. 1 is a diagram showing the relationship between the maximum power operating current and the maximum power operating voltage and the band gap of the top cell of a three-junction solar cell module using a crystalline silicon cell as the bottom cell. [Figure 4] FIG. 1 is a diagram showing the optimum value of the band gap of the middle cell relative to the band gap of the top cell of a three-junction solar cell module using a crystalline silicon cell as the bottom cell. [Figure 5] FIG. 1 is a diagram showing the optimum ratio of the number of series-connected top cells to the number of series-connected middle / bottom cells for the band gap of the top cell in a three-junction solar cell module using a crystalline silicon cell as the bottom cell. [Figure 6] FIG. 10 is a diagram showing the effect on conversion efficiency when the band gap of the middle cell of a three-junction solar cell module using a crystalline silicon cell as the bottom cell deviates from the optimum value. [Figure 7] FIG. 10 is a diagram showing the effect on conversion efficiency when the ratio of the number of series-connected top cells to the number of series-connected middle / bottom cells in a three-junction solar cell module using a crystalline silicon cell as the bottom cell deviates from the optimal value. [Figure 8] FIG. 10 is a diagram showing the effect on the maximum output operating current when the ratio of the number of series-connected top cells to the number of series-connected middle / bottom cells in a three-junction solar cell module using a crystalline silicon cell as the bottom cell deviates from the optimal value. [Figure 9] This figure shows the effect on conversion efficiency when the maximum output operating current of the top module and the maximum output operating current of the middle / bottom modules of a three-junction solar cell module using a crystalline silicon cell as the bottom cell deviate from the optimal value. [Figure 10] FIG. 10 is a diagram showing the band gap dependence of the top cell on the conversion efficiency of a three-junction solar cell module using a Cu(In,Ga)Se 2 cell as the bottom cell. [Figure 11] FIG. 10 is a diagram showing the optimum value of the band gap of the middle cell relative to the band gap of the top cell of a three-junction solar cell module using a Cu(In,Ga)Se 2 cell as the bottom cell. [Figure 12]FIG. 10 is a diagram showing the optimum ratio of the number of series-connected top cells to the number of series-connected middle / bottom cells for the band gap of the top cell in a three-junction solar cell module using a Cu(In,Ga)Se2 cell as the bottom cell. [Figure 13] FIG. 10 is a diagram showing the band gap dependence of the conversion efficiency of a three-junction solar cell module using an organic-inorganic hybrid perovskite cell as the bottom cell. [Figure 14] FIG. 10 is a diagram showing the optimum value of the band gap of the middle cell relative to the band gap of the top cell in a three-junction solar cell module using an organic-inorganic hybrid perovskite cell as the bottom cell. [Figure 15] FIG. 10 is a diagram showing the optimum ratio of the number of series-connected top cells to the number of series-connected middle / bottom cells for the band gap of the top cell in a three-junction solar cell module using an organic-inorganic hybrid perovskite cell as the bottom cell. [Figure 16] 1 is a cross-sectional view showing a configuration of a solar cell module according to an embodiment of the present invention. [Figure 17] 1 is a cross-sectional view showing a configuration of a solar cell module according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] Figure 1 is a conceptual diagram showing various types of solar cell modules, including (a) a series triple-junction (3S) module, (b) a voltage-matched triple-junction (3VM(2S)) module, and (c) a current-matched triple-junction (3CM(2S)) module.

[0022] The 3S module, 3VM(2S) module and 3CM(2S) module are all configured such that a top cell 10, a middle cell 12 and a bottom cell 14 are stacked from the light incident side.

[0023] The 3S module is a solar cell module having a configuration in which a top cell 10, a middle cell 12, and a bottom cell 14 are directly stacked.

[0024] The 3VM (2S) module has a top cell 10, a middle cell 12, and a bottom cell 14 formed on different substrates, and top Top cells 10 and n mb The 3VM (2S) module is a solar cell module in which n number of top modules are connected in series to form a top module and a middle / bottom module, and the top module and the middle / bottom module are connected in parallel. top and the number of middle / bottom modules n mb By adjusting this, the output voltage of the top module and the middle / bottom modules can be matched.

[0025] The 3CM (2S) module has a top cell 10, a middle cell 12, and a bottom cell 14 formed on different substrates, and top Top cells 10 and n mb The number of middle cells 12 and bottom cells 14 are connected in series to form a top module and a middle / bottom module, respectively, and the top module and the middle / bottom module are connected in series. In a 3CM (2S) module, the number of top modules is n top and the number of middle / bottom modules n mb By adjusting this, the output current of the top module and the middle / bottom modules can be matched.

[0026] The current density-voltage (JV) characteristics of the above various solar cell modules were modeled, and the photoelectric conversion efficiency η SC was calculated.

[0027] Current density j of a solar cell (single cell) (SC) is expressed by equation (1) derived from an equivalent circuit consisting of a constant current source, a diode, and a series resistor.

number

[0028] where j ph ,j0,r s are the photocurrent density, reverse saturation current density of the diode, and series resistance, respectively. B , T are the elementary charge, Boltzmann constant, and temperature of the element (300 K), respectively. The external quantum efficiency of photoelectric conversion η EQE is approximately a constant value independent of photon energy, the photocurrent density j ph is the band gap E of the light-absorbing material used in the cell g and the photon number spectrum of sunlight n sun (hbarω) (where hbar is the value obtained by dividing Planck's constant h by 2π).

number

[0029] In the case of multi-junction cells, the upper limit of the integration range in equation (2) changes depending on the cell position. For the middle cells of 3S, 3VM(2S), and 3CM(2S) modules, it is the band gap of the respective top cells, and for the bottom cells, it is the band gap of the respective middle cells. For the diode reverse saturation current density j0, the external luminous efficiency η, which is the ratio of the radiative recombination component expressed by the generalized Planck's law to the total recombination current density, which includes both radiative and non-radiative processes, is ERE Introducing this, we obtain equation (3).

number

[0030] where the Fermi-Dirac distribution function is approximated by the Boltzmann distribution function, where h and c are Planck's constant and the speed of light in a vacuum, respectively.

[0031] The current density j of the solar cell (single cell) in equation (1) (SC) The JV characteristics and photoelectric conversion efficiency η of each three-junction solar cell module in which cells with the characteristics expressed by SC asked for.

[0032] The current density-voltage (JV) characteristics of the various solar cell modules described above can be found by solving the simultaneous equations of the following formulas (4) to (6): top [v top ], j mid [v mid ], j bot [v bot ] are the current-voltage characteristics of the top cell, middle cell, and bottom cell, respectively, expressed by Equation (1). <3S solar cell module>

number

number

number

[0033] Photoelectric conversion efficiency η SC is the solar intensity P for the maximum value of the product of the current density J and voltage V as a function of voltage V. sun and is expressed by equation (7).

number

[0034] The resistance loss of the transparent conductive film and wiring, and the loss due to light absorption and reflection that do not contribute to photoelectric conversion were ignored.

[0035] In the numerical calculation, the external quantum efficiency η of photoelectric conversion was calculated by fitting the power generation characteristics obtained by Equation (1) for each of the organic-inorganic hybrid perovskite (PVK) solar cell, silicon (Si) solar cell, and Cu(In,Ga)Se2 (CIGS) solar cell so that the values ​​obtained were close to the measured values ​​of the cells with the highest conversion efficiencies. EQE , external luminous efficiency η ERE , series resistance rs The values ​​of were used.

[0036] Table 1 shows the external quantum efficiency η used in the model equation (Equation (1)) for the current density-voltage characteristics of single-junction solar cells made of organic-inorganic hybrid perovskite (PVK), crystalline silicon (Si), and Cu(In,Ga)Se2 (CIGS). EQE , external luminous efficiency η ERE , and series resistance r s and the short circuit current density j SC , open circuit voltage v OC , form factor ff, and photoelectric conversion efficiency η SC The calculated results and measured values ​​are shown below. [Table 1]

[0037] The measured values ​​for PVK solar cells are cited from H. Min, DY Lee, J. Kim, G. Kim, KS Lee, J. Kim, MJ Paik, YK Kim, KS Kim, MG Kim, TJ Shin, and SI Seok, Nature 598, 444 (2021). The measured values ​​for Si solar cells are cited from K. Yoshikawa, H. Kawasaki, W. Yoshida, T. Irie, K. Konishi, K. Nakano, T. Uto, D. Adachi, M. Kanematsu, H. Uzu, and Ki Yamamoto, Nat. Energy 2, 17032 (2017). The measured values ​​for Cu(In,Ga)Se2 solar cells are cited from M. Nakamura, K. Yamaguchi, Y. Kimoto, Y. Yasaki, T. Kato, and H. Sugimoto, IEEE J. Photovolt. 9, 1863 (2019).

[0038] Under standard conditions of AM1.5G light irradiation (Reference Solar Spectral Irradiance: Air Mass 1.5, National Renewable Energy Laboratory, available from https: / / rredc.nrel.gov / solar / spectra / am1.5 / ) at a temperature of 300K, the bandgap E g (top) Photoelectric conversion efficiency η SC The band gap of the middle cell, E g (mid) , for 3VM(2S) modules and 3CM(2S) modules, the ratio of the number of middle / bottom cells to the number of top cells is n mb / n top was optimized.

[0039] The number of top cells is n top , the number of bottom cells n bot and the number of middle / bottom cells n mb However, in a large solar cell module, the number of top cells n top , the number of bottom cells n bot and the number of middle / bottom cells n mb If there are many, the ratio of the number of bottom cells to the number of top cells, n bot / n top and the ratio of the number of middle / bottom cells to the number of top cells, n mb / n top can be set in fine increments, and therefore these ratios were treated as continuous variables.

[0040] First, we will show the characteristics of a three-junction solar cell module using organic-inorganic hybrid perovskite cells for the top and middle cells and a crystalline silicon cell for the bottom cell. Figure 2 shows the bandgap E g (top) Photoelectric conversion efficiency η SC The photoelectric conversion efficiency η of the 3VM(2S) module and the 3CM(2S) module is SCSince the photoelectric conversion efficiency of the 3CM(2S) module is equal to the photoelectric conversion efficiency of the 3CM(2S) module, only the photoelectric conversion efficiency of the 3CM(2S) module is shown in Figure 2. SC is the bandgap E of the top cell g (top) Therefore, the band gap E of the top cell g (top) In the case of 1.7 eV to 1.8 eV, which is the current practical upper limit of SC is significantly higher than that of the 3S module.

[0041] Figure 3 shows the maximum power operating current J for the 3VM(2S) and 3CM(2S) modules. MPP and maximum output operating voltage V MPP The results of comparing the band gap E g (top) Even in this case, the 3CM(2S) module has a higher voltage and lower current. The current density of the 3CM(2S) module is roughly half that of the 3VM(2S) module, so the resistance loss of the wiring is reduced to roughly one-quarter. Furthermore, to keep the resistance loss at the same level, the cross-sectional area of ​​the wiring of the 3CM(2S) module can be reduced to roughly one-quarter that of the 3VM(2S) module. Therefore, by applying the 3CM(2S) module, manufacturing costs and weight can be reduced.

[0042] Figures 4 and 5 show the bandgap E of the middle cell of the 3CM(2S) module. g (mid) and the number of series connections of the top cells in the module, n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top These values ​​are fitted using the equations shown in the figure.

[0043] Figures 6 to 9 show the band gap E of the middle cell used in the 3CM (2S) module. g(mid) and the number of series connections of the top cells in the module, n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top The results of investigating the effect when deviates from the optimal value are shown below.

[0044] Top cell bandgap E g (top) The band gap E of the top cell is preferably 1.6 eV or more and 2.4 eV or less. g (top) In the case of the current practical upper limit of 1.7 eV, and assuming that development of high durability progresses in the future, the band gap E g (top) The results are shown for the case where is 2.0 eV.

[0045] As shown in Figure 6, in both cases, the bandgap E g (mid) If is within ±0.1 eV of the optimum value, a high photoelectric conversion efficiency η of approximately 90% of the optimum value is achieved. SC As shown in Figure 7, the number of series-connected top cells, n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top If is in the range of optimal value × 0.75 to optimal value × 1.25, a high photoelectric conversion efficiency η of approximately 90% or more of the optimal value is obtained. SC is obtained.

[0046] If the bottom cell is a crystalline silicon cell, the bandgap E of the middle cell g (mid) is the bandgap E of the top cell g (top) 0.30E g (top) It is preferable that the value satisfies +0.88±0.1 eV.

[0047] Number of series-connected top cells n topThe number of series-connected middle / bottom cells for mb The ratio of n mb / n top When is at the optimum value, the maximum output operating current (J MPP (top) ,J MPP (mb) ) are almost the same. However, the number of series-connected top cells n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top If deviates from the optimum value, the maximum output operating current J of the top module will decrease as shown in Figure 8. MPP (top) and the maximum output operating current J of the middle / bottom modules MPP (mb) There will be differences.

[0048] Figure 9 shows the maximum output operating current J of the top module. MPP (top) and the maximum output operating current J of the middle / bottom modules MPP (mb) Photoelectric conversion efficiency η as a function of the difference (relative value) SC The results are shown below. g (top) In the case of 2|J MPP (top) -J MPP (mb) | / |J MPP (top) +J MPP (mb) If |<0.3, the number of series-connected top cells n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top The optimal value of (J MPP (top) =J MPP (mb) ) with a high photoelectric conversion efficiency of approximately 90% or more SC is obtained.

[0049] If the bottom cell is a crystalline silicon cell, the number of series-connected top cells is n top and the number of series-connected middle / bottom cells n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.41(E g (top) ) 2 -7.13E g (top) +5.63}×0.75 to {2.41(E g (top) ) 2 -7.13E g (top) It is preferable that the above formula satisfies the above formula {+5.63}×1.25.

[0050] Figure 10 shows the band gap E of the top cell when the bottom cell is replaced from a crystalline silicon cell to a Cu(In,Ga)Se2 cell. g (top) Photoelectric conversion efficiency η SC 11 and 12 show the dependence of the band gap E of the middle cell of the 3CM(2S) module when the bottom cell is replaced from crystalline silicon to Cu(In,Ga)Se2 cell. g (mid) and the number of series connections of the top cells in the module, n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top These values ​​are fitted using the equations shown in the figure.

[0051] As shown in these figures, when the bottom cell was changed from a crystalline silicon cell to a Cu(In,Ga)Se2 cell, the same results as in the case of a crystalline silicon cell were obtained.

[0052] When the bottom cell is a Cu(In,Ga)Se2 cell, the band gap E of the middle cell is g (mid) is the bandgap E of the top cell g(top) 0.31E g (top) It is preferable that the value satisfies +0.86±0.1 eV.

[0053] In addition, when the bottom cell is a Cu(In,Ga)Se2 cell, the number of series-connected top cells n top and the number of series-connected middle / bottom cells n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.36(E g (top) ) 2 -6.96E g (top) +5.49}×0.75 to {2.36(E g (top) ) 2 -6.96E g (top) It is preferable that the above formula satisfies {+5.49}×1.25.

[0054] Figure 13 shows the band gap E of the top cell when the bottom cell is replaced from a crystalline silicon cell to an organic-inorganic hybrid perovskite cell (band gap 1.2 eV). g (top) Photoelectric conversion efficiency η SC 14 and 15 show the dependence of the band gap E of the middle cell of the 3CM(2S) module when the bottom cell is replaced from crystalline silicon to an organic-inorganic hybrid perovskite cell. g (mid) and the number of series connections of the top cells in the module, n top The number of series-connected middle / bottom cells for mb The ratio of n mb / n top These values ​​are fitted using the equations shown in the figure.

[0055] As shown in these figures, when the bottom cell was changed from a crystalline silicon cell to an organic-inorganic hybrid perovskite cell, similar results to those obtained with a crystalline silicon cell were obtained.

[0056] When the bottom cell is an organic-inorganic hybrid perovskite cell, the band gap E of the middle cell g (mid) is the bandgap E of the top cell g (top) 0.33E g (top) It is preferable that the value satisfies +0.89±0.1 eV.

[0057] In addition, when the bottom cell is an organic-inorganic hybrid perovskite cell, the number of series-connected top cells n top and the number of series-connected middle / bottom cells n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.17(E g (top) ) 2 -6.45E g (top) +5.07}×0.75 to {2.17(E g (top) ) 2 -6.45E g (top) It is preferable that the above formula satisfies {+5.07}×1.25.

[0058] Figures 16 and 17 show an example configuration of a solar cell module 100 in which a top module 20 in which multiple top cells 10 are connected in series and a middle / bottom module 22 in which multiple middle / bottom stacked cells in which middle cells 12 and bottom cells 14 are stacked and connected in series are connected in series.

[0059] 16 shows a solar cell module 100 having a configuration in which an integrated top module 20, in which semi-transparent top cells 10 formed on a light-transmitting substrate 24 are connected in series, and an integrated bottom module 22, in which middle cells 12 and bottom cells 14 formed on a substrate 26 are stacked and connected in series, are connected in series. Here, the light-transmitting substrate 24 constituting the top module 20 is arranged so as to be on the light incident side, and the substrate 26 constituting the bottom module 22 is arranged so as to be on the opposite side from the light incident side.

[0060] In this configuration, for example, it is preferable that the bottom cell 14 is a Cu(In,Ga)Se2 cell, and the middle cell 12 and the top cell 10 are organic-inorganic hybrid perovskite cells.

[0061] 17 shows a solar cell module 100 having a configuration in which an integrated top module 20, in which semi-transparent top cells 10 formed on a translucent substrate 24 are connected in series, and an integrated bottom module 22, in which middle cells 12 and bottom cells 14 formed on a translucent substrate 30 are stacked and connected in series, are connected in series. Here, the translucent substrate 24 constituting the top module 20 is arranged so as to be on the light incident side, and the translucent substrate 30 constituting the bottom module 22 is also arranged so as to be on the light incident side.

[0062] In this configuration, for example, it is preferable that the bottom cell 14 is an organic-inorganic hybrid perovskite cell, and the middle cell 12 and the top cell 10 are also organic-inorganic hybrid perovskite cells.

[0063] In any solar cell module 100, it is preferable to match the currents of the top module 20 and the bottom module 22 as described above.

[0064] [Configuration of the present invention] [Configuration 1] A solar cell module combining a top cell, a middle cell, and a bottom cell, each of which has a different band gap, The number n of the top cells is top The number of middle / bottom stacked cells, which are made by stacking the middle cell and the bottom cell in series and connecting them in series, is n mb Stacking the serially connected middle / bottom modules with the middle / bottom modules on the light incident side; The top module and the middle / bottom module are connected in series; The number n top and the number n mb The ratio of n mb / n top is the maximum output operating current J of the top module MPP (top) and the maximum output operating current J of the middle / bottom modules MPP (mb) 2|J MPP (top) -J MPP (mb) | / |J MPP (top) +J MPP (mb) A solar cell module characterized by being set to satisfy |<0.3. [Configuration 2] The solar cell module according to configuration 1, The bandgap E of the top cell g (top) is a solar cell module characterized in that the luminance is 1.6 eV or more and 2.4 eV or less. [Configuration 3] The solar cell module according to configuration 1 or 2, The solar cell module is characterized in that the bottom cell is at least one of a crystalline silicon cell, a Cu(In,Ga)Se2 cell, and an organic-inorganic hybrid perovskite cell. [Configuration 4] The solar cell module according to configuration 3, When the bottom cell is a crystalline silicon cell, The bandgap E of the middle cell g (mid) is the bandgap E of the top cell g(top) 0.30E g (top) A solar cell module characterized by satisfying +0.88±0.1eV. [Configuration 5] The solar cell module according to configuration 3, If the bottom cell is a Cu(In,Ga)Se cell, The bandgap E of the middle cell g (mid) is the bandgap E of the top cell g (top) 0.31E g (top) A solar cell module characterized by satisfying +0.86±0.1eV. [Configuration 6] The solar cell module according to configuration 3, When the bottom cell is an organic-inorganic hybrid perovskite cell, The bandgap E of the middle cell g (mid) is the bandgap E of the top cell g (top) 0.33E g (top) A solar cell module characterized by satisfying +0.89±0.1eV. [Configuration 7] The solar cell module according to configuration 3 or 4, When the bottom cell is a crystalline silicon cell, The number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.41(E g (top) ) 2 -7.13E g (top) +5.63}×0.75 to {2.41(E g (top) ) 2 -7.13E g (top)+5.63}×1.25. [Configuration 8] The solar cell module according to configuration 3 or 5, If the bottom cell is a Cu(In,Ga)Se cell, The number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.36(E g (top) ) 2 -6.96E g (top) +5.49}×0.75 to {2.36(E g (top) ) 2 -6.96E g (top) +5.49}×1.25. [Configuration 9] The solar cell module according to configuration 3 or 6, When the bottom cell is an organic-inorganic hybrid perovskite cell, The number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.17(E g (top) ) 2 -6.45E g (top) +5.07}×0.75 to {2.17(E g (top) ) 2 -6.45E g (top) +5.07}×1.25. [Configuration 10] The solar cell module according to any one of configurations 1 to 9, The solar cell module is characterized in that the top cell and the middle cell are organic-inorganic hybrid perovskite cells. [Configuration 11] The solar cell module according to any one of configurations 1 to 10, The top module is an integrated solar cell module formed on a light-transmitting substrate. The solar cell module is characterized in that the middle / bottom module is an integrated type two-series solar cell module formed on a substrate. [Explanation of symbols]

[0065] 10 top cell, 12 middle cell, 14 bottom cell, 20 top module, 22 middle / bottom module, 22 bottom module, 24 light-transmitting substrate, 26 substrate, 30 light-transmitting substrate, 100 solar cell module.

Claims

1. A solar cell module combining a top cell, a middle cell, and a bottom cell, each of which has a different band gap, The number n of the top cells is determined from the light incident side. top The number of top modules connected in series and the number of middle / bottom stacked cells in which the middle cell and the bottom cell are stacked and connected in series is n mb The serially connected middle / bottom modules are stacked with the middle / bottom modules on the light incident side; The top module and the middle / bottom module are connected in series; The number n top and the number n mb The ratio of n mb / n top is the maximum output operating current J of the top module MPP (top) and the maximum output operating current J of the middle / bottom module MPP (mb) 2 | J MPP (top) -J MPP (mb) | / |J MPP (top) +J MPP (mb) A solar cell module characterized in that it is set to satisfy |<0.

3.

2. The solar cell module according to claim 1, The bandgap E of the top cell g (top) is 1.6 eV or more and 2.4 eV or less.

3. The solar cell module according to claim 1 or 2, The bottom cell is a crystalline silicon cell, Cu(In,Ga)Se 2 A solar cell module comprising at least one of a solar cell, an organic-inorganic hybrid perovskite cell, and an organic-inorganic hybrid perovskite cell.

4. The solar cell module according to claim 3, When the bottom cell is a crystalline silicon cell, The band gap E of the middle cell g (mid) is the bandgap E of the top cell g (top) For example, 0.30E g (top) A solar cell module characterized by satisfying +0.88±0.1 eV.

5. The solar cell module according to claim 3, The bottom cell is Cu(In,Ga)Se 2 If it is a cell, The band gap E of the middle cell g (mid) is the bandgap E of the top cell g (top) For 0.31E g (top) A solar cell module characterized by satisfying +0.86±0.1 eV.

6. The solar cell module according to claim 3, When the bottom cell is an organic-inorganic hybrid perovskite cell, The band gap E of the middle cell g (mid) is the bandgap E of the top cell g (top) For 0.33E g (top) A solar cell module characterized by satisfying +0.89±0.1 eV.

7. The solar cell module according to claim 3, When the bottom cell is a crystalline silicon cell, The number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.41(E g (top) ) 2 -7.13E g (top) +5.63} × 0.75 to {2.41 (E g (top) ) 2 -7.13E g (top) +5.63} × 1.

25.

8. The solar cell module according to claim 3, The bottom cell is Cu(In,Ga)Se 2 If it is a cell, The number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.36(E g (top) ) 2 -6.96E g (top) +5.49} × 0.75 to {2.36(E g (top) ) 2 -6.96E g (top) +5.49} × 1.

25.

9. The solar cell module according to claim 3, When the bottom cell is an organic-inorganic hybrid perovskite cell, The number n top and the number n mb The ratio of n mb / n top is the bandgap E of the top cell g (top) For {2.17(E g (top) ) 2 -6.45E g (top) +5.07} × 0.75 to {2.17(E g (top) ) 2 -6.45E g (top) +5.07} × 1.

25.

10. The solar cell module according to claim 1, The solar cell module is characterized in that the top cell and the middle cell are organic-inorganic hybrid perovskite cells.

11. The solar cell module according to claim 1, The top module is an integrated solar cell module formed on a light-transmitting substrate. The solar cell module is characterized in that the middle / bottom module is an integrated type two-series solar cell module formed on a substrate.

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