US-12628490-B2 - Solar cell

US12628490B2US 12628490 B2US12628490 B2US 12628490B2US-12628490-B2

Abstract

A solar cell includes a first substrate, a first electrode layer, a first electron transport layer, a first photoelectric conversion layer, a first hole transport layer, a second electrode layer, a third electrode layer, a second electron transport layer, a second photoelectric conversion layer, a second hole transport layer, a fourth electrode layer, and a second substrate that are disposed in the order stated. The first photoelectric conversion layer includes a first perovskite compound, and the second photoelectric conversion layer includes a second perovskite compound. The first perovskite compound has a bandgap greater than a bandgap of the second perovskite compound.

Inventors

Taisuke Matsui
Hiroshi Higuchi
Kenji Kawano
Akio Matsushita
Takayuki Negami

Assignees

PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20220927
Priority Date: 20200427

Claims (7)

1 . A solar cell comprising a first cell and a second cell, the first cell comprising: a first substrate, a first electrode layer, a first electron transport layer, a first photoelectric conversion layer, a first hole transport layer, and a second electrode layer, disposed in the order stated, and the second cell comprising: a second substrate, a fourth electrode layer, a second hole transport layer, second photoelectric conversion layer, a second electron transport layer, and a third electrode layer, disposed in the order stated; wherein the first cell and the second cell are arranged such that there is a space between the second electrode layer and the third electrode layer, the space being filled with air or a filler, the first photoelectric conversion layer includes a first perovskite compound, the second photoelectric conversion layer includes a second perovskite compound, the first perovskite compound has a bandgap greater than a bandgap of the second perovskite compound, and the solar cell has one of the following configurations, (i), (ii), or (iii): (i) the first electrode layer and the fourth electrode layer are electrically connected to each other, (ii) the second electrode layer and the third electrode layer are electrically connected to each other, or (iii) the first electrode layer and the third electrode layer are electrically connected to each other, and the second electrode layer and the fourth electrode layer are electrically connected to each other.
2 . The solar cell according to claim 1 , wherein the first electron transport layer includes a metal oxide.
3 . The solar cell according to claim 2 , wherein the metal oxide includes, as a major component, at least one selected from the group consisting of titanium oxide and tin oxide.
4 . The solar cell according to claim 1 , wherein the filler includes at least one selected from the group consisting of epoxy resins, silicone resins, and polyolefin-based resins.
5 . The solar cell according to claim 1 , wherein the solar cell has the configuration (i), and the first electrode layer and the fourth electrode layer are connected to each other with a wire.
6 . The solar cell according to claim 1 , wherein the solar cell has the configuration (ii), and the second electrode layer and the third electrode layer are connected to each other with a wire.
7 . The solar cell according to claim 1 , wherein the solar cell has the configuration (iii), the first electrode layer and the third electrode layer are connected to each other with a wire, and the second electrode layer and the fourth electrode layer are connected to each other with a wire.

Description

BACKGROUND 1. Technical Field The present disclosure relates to a solar cell. 2. Description of the Related Art In recent years, research and development of perovskite solar cells have been advanced to provide a new solar cell that can replace the existing silicon-based solar cell. Perovskite solar cells use, as a photoelectric conversion material, a perovskite compound represented by a chemical formula of ABX3, where A is a monovalent cation, B is a divalent cation, and X is a halogen anion. Julian Burschka et al., “Sequential deposition as a route to high-performance perovskite-sensitized solar cells”, Nature, vol. 499, pp. 316-319, 18 Jul. 2013 [DOI:10.1038/nature12340] discloses a perovskite solar cell that uses, as a photoelectric conversion material for the perovskite solar cell, a perovskite compound represented by a chemical formula of CH3NH3PbI3 (hereinafter referred to as “MAPBI3”). In the perovskite solar cell disclosed in Julian Burschka et al., the perovskite compound represented by MAPbI3, TiO2, and Spiro-OMeTAD are used as a photoelectric conversion material, an electron transport material, and a hole transport material, respectively. “Monolithic all-perovskite tandem solar cells with 24.8% efficiency exploiting comproportionation to suppress Sn(ii) oxidation in precursor ink”, Nature Energy, vol. 4, pp. 864-873, 2019 [DOI: https://doi.org/10.1038/s41560-019-0466-3] discloses a perovskite tandem solar cell. Perovskite tandem solar cells have a configuration in which multiple solar cells that use perovskite compounds are stacked together, with bandgaps of the perovskite compounds being different from each other. Perovskite tandem solar cells can improve photoelectric conversion efficiency. SUMMARY One non-limiting and exemplary embodiment provides a perovskite tandem solar cell that has high photoelectric conversion efficiency, without compromising industrial productivity. In one general aspect, the techniques disclosed here feature a solar cell including a first substrate, a first electrode layer, a first electron transport layer, a first photoelectric conversion layer, a first hole transport layer, a second electrode layer, a third electrode layer, a second electron transport layer, a second photoelectric conversion layer, a second hole transport layer, a fourth electrode layer, and a second substrate that are disposed in the order stated. The first photoelectric conversion layer includes a first perovskite compound. The second photoelectric conversion layer includes a second perovskite compound. The first perovskite compound has a bandgap greater than a bandgap of the second perovskite compound. The present disclosure provides a perovskite tandem solar cell that has high photoelectric conversion efficiency, without compromising industrial productivity. Additional benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. The benefits and/or advantages may be individually obtained by the various embodiments and features of the specification and drawings, which need not all be provided in order to obtain one or more of such benefits and/or advantages. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a schematic cross-sectional view of an example of a typical perovskite tandem solar cell having two terminals; FIG. 1B is a schematic cross-sectional view of a modification of a typical perovskite tandem solar cell having two terminals; FIG. 2 is a perspective view of a perovskite tandem solar cell according to a first embodiment; FIG. 3 is a cross-sectional view of the perovskite tandem solar cell illustrated in FIG. 2 taken along line III-III; FIG. 4 is a schematic cross-sectional view of a perovskite tandem solar cell according to a second embodiment; FIG. 5 is a schematic cross-sectional view of a perovskite tandem solar cell according to a third embodiment; FIG. 6 is a schematic cross-sectional view of a perovskite tandem solar cell according to a fourth embodiment; and FIG. 7 is a schematic cross-sectional view of an example of a solar cell module including the perovskite tandem solar cells of the fourth embodiment. DETAILED DESCRIPTIONS Definitions of Terms As used in this specification, the term “perovskite compound” means a perovskite crystal structure represented by a chemical formula of ABX3, where A is a monovalent cation, B is a divalent cation, and X is a halogen anion, and also means a structure having a crystal similar to that of the perovskite crystal structure. As used in this specification, the term “lead-type perovskite compound” means a perovskite compound containing a Pb cation as a divalent cation. As used in this specification, the term “tin-lead-combined perovskite compound” means a perovskite compound containing both a Sn cation and a Pb cation as divalent cations. As used in this specification, the term “perovskite solar cell” means a solar cell including a perovskite compound as a photoelectric conversion material. As used