A method for preparing TOPCon battery substrate and double-sided electroplated TOPcon battery prepared therefrom are provided. The method includes: providing a double-sided grooved silicon matrix of a TOPCon battery; carrying out thermal repair treatment on the silicon matrix; respectively carrying out light injection treatment on the front side and the back side of the silicon matrix after thermal repair treatment, thereby the TOPCon battery substrate is obtained. Thermal repair treatment can greatly increase the overall lattice thermal motion of the silicon substrate, and light is injected into the front side and the back side in the directions of two different light incidence surfaces, so that both the front side and the back side can absorb light, thereby repairing the defects at the interface between the amorphous silicon and the silicon wafer and improving the quality of the PN junctions.

A method for preparing TOPCon battery substrate and double-sided electroplated TOPcon battery prepared therefrom are provided. The method includes: providing a double-sided grooved silicon matrix of a TOPCon battery; carrying out thermal repair treatment on the silicon matrix; respectively carrying out light injection treatment on the front side and the back side of the silicon matrix after thermal repair treatment, thereby the TOPCon battery substrate is obtained. Thermal repair treatment can greatly increase the overall lattice thermal motion of the silicon substrate, and light is injected into the front side and the back side in the directions of two different light incidence surfaces, so that both the front side and the back side can absorb light, thereby repairing the defects at the interface between the amorphous silicon and the silicon wafer and improving the quality of the PN junctions.

A solar cell according to an embodiment includes a p-electrode, a p-type light-absorbing layer containing a cuprous oxide or/and a complex oxide of cuprous oxides as a main component on the p-electrode, an n-type layer containing an oxide containing Ga on the p-type light-absorbing layer, and an n-electrode. A first region is included between the p-type light-absorbing layer and the n-type layer. The first region is a region from a depth of 2 nm from an interface between the p-type light-absorbing layer and the n-type layer toward the p-type light absorbing layer to a depth of 2 nm from the interface between the p-type light-absorbing layer and the n-type layer toward the n-type layer. Cu, Ga, M1, and O are contained in the first region. M1 is one or more elements selected from the group consisting of Sn, Sb, Ag, Li, Na, K, Cs, Rb, Al, In, Zn, Mg, Si, Ge, N, B, Ti, Hf, Zr, and Ca. A ratio of Cu, Ga, M1, and O is a1:b1:c1:d1. a1, b1, c1, and d1 satisfy 1.80a12.20, 0.005b10.05, 0c10.20, and 0.60d11.00.

A solar cell according to an embodiment includes a p-electrode, a p-type light-absorbing layer containing a cuprous oxide or/and a complex oxide of cuprous oxides as a main component on the p-electrode, an n-type layer containing an oxide containing Ga on the p-type light-absorbing layer, and an n-electrode. A first region is included between the p-type light-absorbing layer and the n-type layer. The first region is a region from a depth of 2 nm from an interface between the p-type light-absorbing layer and the n-type layer toward the p-type light absorbing layer to a depth of 2 nm from the interface between the p-type light-absorbing layer and the n-type layer toward the n-type layer. Cu, Ga, M1, and O are contained in the first region. M1 is one or more elements selected from the group consisting of Sn, Sb, Ag, Li, Na, K, Cs, Rb, Al, In, Zn, Mg, Si, Ge, N, B, Ti, Hf, Zr, and Ca. A ratio of Cu, Ga, M1, and O is a1:b1:c1:d1. a1, b1, c1, and d1 satisfy 1.80a12.20, 0.005b10.05, 0c10.20, and 0.60d11.00.

A multi-junction, photovoltaic (PV) solar cell with an integrated, monolithic blocking diode, and methods of fabrication, are disclosed. The integrated, monolithic blocking diode protects a circuit of PV solar cells when some PV solar cells are shadowed. A triple-junction PV solar cell includes a first conductive substrate with a PV solar cell stack and an adjacent blocking diode stack disposed on a common conductive substrate. A trench is located in between the two stacks, which provides electrical isolation. A triple-junction cell has: a Ge first PN junction, a GaAs second PN junction, and an InGaP third PN junction. A first metal contact is disposed on a portion of the PV solar cell stack, and a second metal contact is disposed completely across the blocking diode stack. Extraterrestrial satellites can use these triple-junction PV solar cells with integrated, monolithic blocking diodes.

An electrical connection is formed between first and second conductive elements, by inserting a nano-metal material between the first and second conductive elements; and heating the nano-metal material to a melting temperature to form the electrical connection between the first and second conductive elements. The nano-metal material may comprise a nano-metal paste or ink comprised of one or more of Gold (Au), Copper (Cu), Silver (Ag), and/or Aluminum (Al) nano-particles that melt or fuse into a solid to form the electrical connection, at a melting temperature of about 150-250 degrees C., and more preferably, about 175-225 degrees C. The electrical connection may be formed between a solar cell and a substrate by creating a via in the solar cell between a front and back side of the solar cell, wherein the via is connected to a contact on the front side of the solar cell and a trace on the substrate.

An electrical connection is formed between first and second conductive elements, by inserting a nano-metal material between the first and second conductive elements; and heating the nano-metal material to a melting temperature to form the electrical connection between the first and second conductive elements. The nano-metal material may comprise a nano-metal paste or ink comprised of one or more of Gold (Au), Copper (Cu), Silver (Ag), and/or Aluminum (Al) nano-particles that melt or fuse into a solid to form the electrical connection, at a melting temperature of about 150-250 degrees C., and more preferably, about 175-225 degrees C. The electrical connection may be formed between a solar cell and a substrate by creating a via in the solar cell between a front and back side of the solar cell, wherein the via is connected to a contact on the front side of the solar cell and a trace on the substrate.

A low bandgap absorber region (LBAR) used in a laser power converter (LPC). The laser power converter is comprised of one or more subcells on a substrate, wherein at least one of the subcells has an emitter and base, with the low bandgap absorber region coupled between the emitter and base. The emitter and base are comprised of a material with a bandgap higher than a wavelength of incident laser light, and the low bandgap absorber region is comprised of a material with a bandgap lower than the emitter and base. The emitter and base are transparent to the incident laser light, and the low bandgap absorber region absorbs the incident laser light and generates a current in response thereto, such that the current is controlled by the material and thickness of the low bandgap absorber region. The low bandgap absorber region is configured to produce a current balanced to the subcells connected in series.

A low bandgap absorber region (LBAR) used in a laser power converter (LPC). The laser power converter is comprised of one or more subcells on a substrate, wherein at least one of the subcells has an emitter and base, with the low bandgap absorber region coupled between the emitter and base. The emitter and base are comprised of a material with a bandgap higher than a wavelength of incident laser light, and the low bandgap absorber region is comprised of a material with a bandgap lower than the emitter and base. The emitter and base are transparent to the incident laser light, and the low bandgap absorber region absorbs the incident laser light and generates a current in response thereto, such that the current is controlled by the material and thickness of the low bandgap absorber region. The low bandgap absorber region is configured to produce a current balanced to the subcells connected in series.

A multijunction solar cell including an upper first solar subcell having an emitter and base layers forming a photoelectric junction; a second solar subcell disposed under and adjacent to the upper first solar subcell, and having an emitter and base layers forming a photoelectric junction; and a third solar subcell disposed under and adjacent to the second solar subcell and having an emitter and base layers forming a photoelectric junction; wherein at least one of the base and emitter layers of at least a particular solar subcell from among the upper first solar subcell, the second solar subcell, and the third solar subcell has a graded band gap throughout at least a portion of thickness of its active layer adjacent to the photoelectric junction and being in a range of 20 to 300 MeV greater than a band gap in the active layer in both the emitter layer and the base layer spaced away from the photoelectric junction.