IP Library › Granted Patent US 12,402,437
Granted Patent B2
US 12,402,437 · App. 17/636,271 · Granted Aug 26, 2025

Flexibility-assisted heat removal in thin crystalline silicon solar cells

Inventors: Sang Eon Han (Albuquerque, NM); Sang M. Han (Albuquerque, NM); Seok Jun Han (Albuquerque, NM)
Assignee: UNM RAINFOREST INNOVATIONS
H10F77/703H10F10/165
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Quick Facts
Patent No.
US 12,402,437
App. No.
17/636,271
Granted
Aug 26, 2025
Kind
B2
Abstract

A flexible, non-flat solar cell comprises a flexible substrate. A pn junction is on or in the flexible substrate. The solar cell has been flexed so as to have a non-flat geometry that results in an increased surface area of the flexed solar cell with respect to the surface area of a flat solar cell that is the same as the flexed solar cell except that the flat solar cell has a flat surface geometry that has the same projected area on a lateral plane as does the flexed solar cell.

Claims (16)

1. A flexed, non-flat solar cell, comprising:

a flexible substrate comprising symmetry breaking nanostructures; and

a pn junction that is on or in the flexible substrate;

wherein the flexible substrate has a thickness of about 25 microns or less,

wherein the flexed, non-flat, solar cell is flexed to have a non-flat geometry that results in an increased surface area of the flexed, non-flat, solar cell with respect to a surface area of a flat solar cell that has the same projected area on a lateral plane as does the flexed, non-flat solar cell, and

wherein the non-flat geometry comprises a wavy shape and the surface area of the flexed, non-flat, solar cell is at least 1.1 times greater than that of said flat solar cell covering the same area such that the solar cell has a surface area (Sw) larger than a projected area (So) on its lateral plane by a factor of Sw/So of 1.2 to about 10, and

wherein the wavy shape enhances heat removal of the solar cell when heated by sunlight, such that a reduction in the photovoltaic efficiency of the solar cell due to the wavy shape is less than a gain in photovoltaic efficiency from the enhanced heat removal due to the wavy shape.

2. The solar cell of claim 1 , wherein the flexible substrate comprises crystalline silicon.

3. The solar cell of claim 1 , wherein the flexible substrate is freestanding.

4. The solar cell of claim 1 , wherein the flexible substrate has a thickness of about 0.5 microns to about 25 microns.

5. The solar cell of claim 1 , wherein top and bottom surfaces of the flexed, non-flat, solar cell comprise the wavy shape.

6. The solar cell of claim 5 , wherein an average amplitude of the wavy shape is 0.5 millimeters (mm) to 1 meter.

7. The solar cell of claim 5 , wherein the flexible substrate has a thickness of about 0.5 microns to about 25 microns.

8. The solar cell of claim 1 , wherein the symmetry breaking nanostructures enhance photovoltaic efficiency of the flexed, non-flat, solar cell by light trapping,

wherein the non-flat geometry enhances heat removal of the flexed, non-flat, solar cell, by increasing the surface area, and

wherein the symmetry breaking nanostructures comprise a plurality of inverted nanopyramid arrays.

Assignments (3)
CONFIRMATORY LICENSE Recorded Feb 27, 2025
From: UNIVERSITY OF NEW MEXICO
To: NATIONAL SCIENCE FOUNDATION
Reel/Frame 070345/0664 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 20, 2024
From: HAN, SANG M.; HAN, SANG EON; HAN, SEOK JUN
To: THE REGENTS OF THE UNIVERSITY OF NEW MEXICO
Reel/Frame 068649/0500 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 20, 2024
From: THE REGENTS OF THE UNIVERSITY OF NEW MEXICO
To: UNM RAINFOREST INNOVATIONS
Reel/Frame 068649/0660 →
Continuity (2)
Provisional Application 62895812 · Sep 4, 2019
Related Publication 20220293802A1 · Sep 15, 2022
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