CN213340385U

CN213340385U - Photovoltaic cell structure

Info

Publication number: CN213340385U
Application number: CN202021666973.6U
Authority: CN
Inventors: 葛学斌; 吴守庆; 冯成坤
Original assignee: Shanghai Xianwei Energy Technology Co ltd
Current assignee: Shanghai Xianwei Energy Technology Co ltd
Priority date: 2020-08-12
Filing date: 2020-08-12
Publication date: 2021-06-01
Anticipated expiration: 2030-08-12

Abstract

The utility model discloses a photovoltaic cell technical field a photovoltaic cell structure. Comprises a silicon substrate and is characterized in that: the upper surface of the silicon substrate is an illuminated surface which is a transparent electrode layer; the reverse side of the silicon substrate sequentially comprises an intrinsic silicon film, a functional layer, an optical layer and an electrode from top to bottom, wherein the functional layer is a high-light-transmittance semiconductor layer, and a p-i-n junction is formed by a p-type doped layer, an i-type layer and an n-type doped layer. The photovoltaic cell has the effects of improving the light transmittance, reducing the optical loss of the photovoltaic cell, improving the Isc of the cell and improving the photoelectric conversion efficiency of the cell.

Description

Photovoltaic cell structure

Technical Field

The invention relates to a photovoltaic cell structure in the technical field of photovoltaic cells.

Background

With the scale of the photovoltaic industry and the rapid development of photovoltaic technology, the consumption of a large amount of semiconductor materials and the low energy absorption efficiency thereof are still the shortages of the solar energy industry. A doped amorphous silicon (alpha-Si) film is generally adopted as a core functional layer, and the representative structure is an amorphous/single crystal Heterojunction (HIT) battery; or the doped polycrystalline silicon (Poly-Si) film is used as a core functional layer, the representative structure is a tunneling oxide passivation contact structure (TOPCon) battery, but alpha-Si or Poly-Si absorbs light energy, and the current output capability of the battery is influenced.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art, and provides a crystalline silicon high-efficiency photovoltaic cell structure which can effectively improve the current output capacity of a photovoltaic cell.

The utility model discloses a realize through following technical scheme:

comprises a silicon substrate and is characterized in that: the upper surface of the silicon substrate is an illuminated surface which is a transparent electrode layer; the reverse side of the silicon substrate sequentially comprises an intrinsic silicon film, a functional layer, an optical layer and an electrode from top to bottom, wherein the functional layer is a high-light-transmittance semiconductor layer and is a p-i-n junction formed by a p-type doped layer, an i-type layer and an n-type doped layer; the technical scheme is further explained as follows: the thickness of the functional layer is 5-200 nm; the technical scheme is further explained as follows: the intrinsic silicon film is an amorphous or microcrystalline silicon film, and the thickness of the intrinsic silicon film is 1-20 nm; the technical scheme is further explained as follows: the thickness of the optical layer is 50-80nm, the average refractive index is 1.5-2.4, and the light transmittance is not lower than 80%; the technical scheme is further explained as follows: the transparent electrode layer is made of transparent conductive materials with the refractive index n <1, and the thickness of the transparent electrode layer is less than 50 nm; the technical scheme is further explained as follows: the optical layer is an insulating layer, and the electrode is in physical contact with the functional layer.

Compared with the prior art, the utility model discloses the effect that has the light transmittance that improves, reduces photovoltaic cell's optical loss, improves the current output ability (Isc) of battery and improves the photoelectric conversion efficiency of battery.

Drawings

Fig. 1 is a view showing the structure of a photovoltaic cell.

In the figure: transparent electrode layer 1, silicon substrate 2, intrinsic silicon thin film 3, functional layer 4, optical layer 5 and electrode 6.

Detailed Description

The technical solution of the present invention is further explained with reference to the accompanying drawings and embodiments:

as shown in the figure, the structure diagram of the photovoltaic cell comprises a transparent electrode layer 1, a silicon substrate 2, an intrinsic silicon thin film 3, a functional layer 4, an optical layer 5 and an electrode 6.

The front side of the silicon substrate is provided with a transparent electrode layer, and the back side of the silicon substrate sequentially comprises an intrinsic silicon film, a functional layer, an optical layer and an electrode from top to bottom; the functional layer is a p-i-n junction formed by three layers of a p-type doping layer, an i-type layer and an n-type doping layer, sunlight can enter the functional layer without loss through the transparent electrode layer, and can enter the functional layer again through reflection of the optical layer after sequentially passing through the p-i-n junction formed by the three layers of the p-type doping layer, the i-type layer and the n-type doping layer, and because the refractive index of the transparent electrode layer 1 is far smaller than that of the light absorption layer, incident sunlight easily forms total reflection at the interface of the transparent electrode 1 and the light absorption layer, so that the incident sunlight is reflected into the light absorption layer again, the multiple reflection prolongs the effective optical length of the sunlight in the light absorption layer, and improves the light absorption efficiency of the light absorption layer.

Examples

FIG. 1 is a diagram of a photovoltaic cell structure, which comprises a transparent electrode layer 1, a silicon substrate 2, an intrinsic silicon thin film 3, a functional layer 4, an optical layer 5 and an electrode 6 from top to bottom,

the material of the functional layer is microcrystalline silicon, the refraction n is more than 3.5, the transparent electrode layer is indium tin oxide, the resistivity of the functional layer is 4 orders of magnitude lower than that of the silicon substrate, the thickness of the functional layer is 50nm, the intrinsic silicon layer is amorphous, and the thickness of the intrinsic silicon layer is 3 nm; the thickness of the optical layer is 100nm, the average refractive index is 2.1, and the light transmittance is not lower than 80%; the optical layer is an insulating layer, the electrode is in physical contact with the functional layer to play a role in transmitting current, and the optical layer is a zinc oxide aluminum-doped layer.

The foregoing is a description of certain preferred embodiments of the present invention and is not to be construed as limiting the invention itself. Various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A photovoltaic cell structure comprising a silicon substrate, characterized in that: the upper surface of the silicon substrate is an illuminated surface which is a transparent electrode layer; the reverse side of the silicon substrate sequentially comprises an intrinsic silicon film, a functional layer, an optical layer and an electrode from top to bottom, wherein the functional layer is a high-light-transmittance semiconductor layer, and a p-i-n junction is formed by a p-type doped layer, an i-type layer and an n-type doped layer.

2. The photovoltaic cell structure of claim 1, wherein: the thickness of the functional layer is 5-200 nm.

3. The photovoltaic cell structure of claim 1, wherein: the intrinsic silicon film is an amorphous or microcrystalline silicon film, and the thickness of the intrinsic silicon film is 1-20 nm.

4. The photovoltaic cell structure of claim 1, wherein: the optical layer has a thickness of 50-80nm, an average refractive index of 1.5-2.4, and a light transmittance of not less than 80%.

5. The photovoltaic cell structure of claim 1, wherein: the transparent electrode layer is made of transparent conductive materials with the refractive index n <1, and the thickness of the transparent electrode layer is less than 50 nm.

6. The photovoltaic cell structure of claim 1, wherein: the optical layer is an insulating layer, and the electrode is in physical contact with the functional layer.