Thin film solar cell for bipv and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-2018212090-A1
Application number	US-201715730499-A
Country	US
Kind code	A1
Filing date	Oct 11, 2017
Priority date	Jan 24, 2017
Publication date	Jul 26, 2018
Grant date	—

Abstract

Disclosed is a thin film solar cell for BIPV capable of improving a utility value for the exterior by visually changing a black color of an inorganic thin film solar cell into a color of reflected light therefrom to exhibit an exterior appearance having the color without substantially lowering efficiency required for a solar cell to thereby facilitate commercialization of the inorganic thin film solar cell. Also disclosed is a thin film solar cell for BIPV capable of maintaining a maximum power conversion efficiency (PCE) required for a solar cell when used as a finishing material of a building envelope, and visually changing a black color of an inorganic thin film solar cell into a color of reflected light therefrom to be suitable for the exterior with only a slight reduction of relative harvesting efficiency and a short circuit photocurrent density without a decrease of an open circuit voltage V oc .

First claim

What is claimed is:

1 . A thin film solar cell for BIPV, comprising:
a substrate; an upper surface part of the substrate, the upper surface part including an electrode; and a lower surface part of the substrate, wherein a reflective filter is included in one or more of the upper surface part and the lower surface part, and is configured to reflect a portion of externally emitted light and transmit the remaining portion thereof to visually change a color of the thin film solar cell for BIPV into a color of reflected light therefrom.

2 . The thin film solar cell of claim 1 , wherein the upper surface part includes:
a first rear surface electrode and a front surface electrode which are formed to face each other on one surface of the substrate; a second rear surface electrode formed between the first rear surface electrode and the front surface electrode; and a light absorption layer formed between the second rear surface electrode and the front surface electrode, wherein the front surface electrode is disposed at a side opposite to the substrate based on the first rear surface electrode.

3 . The thin film solar cell of claim 2 , wherein the reflective filter is provided on the front surface electrode.

4 . The thin film solar cell for BIPV of claim 1 , wherein the reflective filter is a one-dimensional photonic crystal dichroic nano-multilayered film.

5 . The thin film solar cell of claim 4 , wherein the one-dimensional photonic crystal dichroic nano-multilayered film is a one-dimensional photonic crystal dichroic nano-multilayered blue color reflective film.

6 . The thin film solar cell of claim 4 , wherein the one-dimensional photonic crystal dichroic nano-multilayered film is configured such that a first layer, a second layer, and a third layer are alternately stacked,
a refractive index of the second layer is different from that of the first layer, and a refractive index of the third layer is the same as or different from that of the first layer.

7 . The thin film solar cell of claim 6 , wherein an optical thickness of each of the first layer and the third layer is in a range of 1/9 to 1/7 optical thickness with respect to a center wavelength of the reflected light, and
an optical thickness of the second layer is in a range of ⅕ to ⅓ optical thickness with respect to the center wavelength of the reflected light.

8 . The thin film solar cell of claim 6 , wherein, when the first layer, the second layer, and the third layer are alternately stacked, a repetition unit configured with the first-second-third layers is repeatedly stacked 3 to 30 times.

9 . The thin film solar cell of claim 1 , wherein a thickness of the reflective filter is in a range of 0.3 to 5 micrometers (μm).

10 . The thin film solar cell of claim 1 , wherein the thin film solar cell is scribed to serially connect the substrate, the upper surface part, and the lower surface part, and the reflective filter is not scribed.

11 . A thin film solar cell for BIPV, comprising:
one or more one-dimensional photonic crystal dichroic nano-multilayered films, wherein the thin film solar cell for BIPV satisfies conditions (a) and (b): (a) A center wavelength of reflected light from each of the one-dimensional photonic crystal dichroic nano-multilayered films is in a range of 380 to 780 nm, and (b) A relational expression 1 is satisfied as follows,

0.75
≤

A
B

≤
1.00

,

[

Relational



Expression



1

]

wherein A is light harvesting efficiency when the one or more one-dimensional photonic crystal dichroic nano-multilayered films are employed, and B is light harvesting efficiency when a one-dimensional photonic crystal dichroic nano-multilayered film is not employed.

12 . The thin film solar cell of claim 11 , wherein further satisfying a condition (c):
(c) A relational expression 2 is satisfied as follows,

0.90
≤

C
D

≤
1.00

,

[

Relational



Expression



2

]

wherein C is an open circuit voltage V oc when the one or more one-dimensional photonic crystal dichroic nano-multilayered films are employed, and D is open circuit voltage V oc when a one-dimensional photonic crystal dichroic nano-multilayered film is not employed.

13 . A window which includes the thin film solar cell of claim 1 .

Assignees

• Univ Kookmin Ind Acad Coop Found
• Korea Inst Sci & Tech

Inventors

• Do Young Rag
• Min Byoung Koun

Classifications

• H01L31/18

  Electricity · mapped topic

• H01L31/022425

  Electricity · mapped topic

• H02S20/26

  Building materials integrated with PV modules, e.g. façade elements (H02S20/25 takes precedence) · CPC title

• H01L31/0549 Primary

  Electricity · mapped topic

• H10F77/211

  for photovoltaic cells · CPC title