CN216389396U

CN216389396U - Device with photovoltaic power generation and thermoelectric power generation functions

Info

Publication number: CN216389396U
Application number: CN202122439138.XU
Authority: CN
Inventors: 张树德; 刘玉申; 况亚伟; 连维飞; 倪志春
Original assignee: Changshu Institute of Technology; Suzhou Talesun Solar Technologies Co Ltd
Current assignee: Changshu Institute of Technology; Suzhou Talesun Solar Technologies Co Ltd
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2022-04-26
Anticipated expiration: 2031-10-11

Abstract

The utility model provides a device with photovoltaic power generation and thermoelectric power generation functions, which comprises a solar cell and a thermoelectric power generation mechanism, wherein the solar cell is provided with a back electrode, the thermoelectric power generation mechanism is provided with a hot end and a cold end, the temperatures of the hot end and the cold end are different when the device works, the device also comprises a heat conduction connecting film, the back electrode is arranged on the front surface of the heat conduction connecting film, and the hot end of the thermoelectric power generation mechanism is arranged on the back surface of the heat conduction connecting film. The device can reduce the operating temperature of solar cell, improves the output power of electric energy.

Description

Device with photovoltaic power generation and thermoelectric power generation functions

Technical Field

The utility model belongs to the field of photovoltaic power generation, and particularly relates to a device with photovoltaic power generation and thermoelectric power generation functions.

Background

Solar energy is inexhaustible renewable energy source and is also clean energy source, and no environmental pollution is generated. Solar photovoltaic technology is one of the most attractive projects in the fastest and most active research field in recent years. For this reason, crystalline silicon solar cells have been developed and developed. The power temperature coefficient of the crystalline silicon solar cell is a negative value, and when the working temperature is increased, the output power of the cell is reduced. Taking PERC solar cell as an example, the power temperature coefficient is about-0.36%/deg.C, and the power output is reduced by 0.36% when the working temperature is increased by 1 deg.C. When the crystalline silicon solar cell actually works, the working temperature of the crystalline silicon solar cell is generally higher than the ambient temperature by more than 25 ℃ because part of absorbed sunlight can be converted into heat energy, and the crystalline silicon solar cell has great influence on the output power of the cell.

Disclosure of Invention

In view of the above problems, it is an object of the present invention to provide a device capable of reducing the operating temperature of a solar cell and increasing the output power of electric energy.

In order to achieve the purpose, the utility model adopts the technical scheme that:

the device comprises a solar cell and a temperature difference power generation mechanism, wherein the solar cell is provided with a back electrode, the temperature difference power generation mechanism is provided with a hot end and a cold end, the device further comprises a heat conduction connection film, the back electrode is arranged on the front surface of the heat conduction connection film, and the hot end of the temperature difference power generation mechanism is arranged on the back surface of the heat conduction connection film.

Preferably, the hot end is connected or bonded to the back side of the back electrode through the heat conduction.

Preferably, the heat-conducting connecting film is any one of heat-conducting silicone grease, heat-conducting glue, liquid metal or a brazing layer.

Preferably, the thermally conductive connection film completely covers the surface of the back electrode or the front surface of the hot end.

Preferably, the thermoelectric generation mechanism includes a P-type semiconductor power generation element and an N-type semiconductor power generation element having a first end closer to the back surface electrode and a second end farther from the back surface electrode, respectively; the thermoelectric generation mechanism further comprises a first conductor for connecting the first end of the P-type semiconductor element and the first end of the N-type semiconductor element in a conduction manner.

Preferably, the thermoelectric generation mechanism further includes a first ceramic layer and a second ceramic layer, the first ceramic layer is provided on the back surface of the heat-conducting connection film, the P-type semiconductor power generation element and the N-type semiconductor power generation element are located between the first ceramic layer and the second ceramic layer, and the first conductor is connected or in contact with the first ceramic layer.

Preferably, the thermoelectric generation mechanism further includes a second conductor for connecting the second end of the P-type semiconductor element and the second end of the N-type semiconductor element in a conduction manner, at least the number of the P-type semiconductor generation elements is plural, or at least the number of the N-type semiconductor generation elements is plural, and the P-type semiconductor generation elements and the N-type semiconductor generation elements are alternately arranged and sequentially connected in series through the first conductor and the second conductor.

Preferably, the first ceramic layer and the second ceramic layer are each alumina ceramics.

Preferably, the first conductor and the second conductor are each copper, aluminum, a copper alloy, or an aluminum alloy.

Preferably, the P-type semiconductor power generation element is a P-type bismuth telluride semiconductor, and the N-type semiconductor power generation element is an N-type bismuth telluride semiconductor.

Preferably, the device further comprises an external power supply, the device has a thermoelectric power generation state and a refrigeration state for cooling the solar cell, when the thermoelectric power generation state is adopted, the external power supply is turned off, and the temperature of the hot end is higher than that of the cold end; in the refrigeration state, the external power supply supplies power to the temperature difference power generation device, and the temperature of the hot end is lower than that of the cold end.

Preferably, the solar cell is a PERC cell, a TOPCon cell or an HJT cell.

Preferably, the solar cell comprises a reflection reducing layer, an N-type silicon layer, a P-type silicon substrate and a passivation layer which are sequentially stacked from top to bottom, the solar cell further comprises a front electrode arranged on the reflection reducing layer, the front electrode penetrates through the reflection reducing layer and is in ohmic contact with the N-type silicon layer, and the back electrode covers the passivation layer and is partially in ohmic contact with the P-type silicon substrate.

By adopting the technical scheme, compared with the prior art, the utility model has the following advantages:

according to the device with the photovoltaic power generation and thermoelectric power generation functions, the solar cell is connected with the hot end of the thermoelectric power generation mechanism through the heat conduction connecting film, and when the device works, heat generated by the solar cell is transferred to the thermoelectric power generation mechanism through the heat conduction connecting film, so that on one hand, heat energy generated by the crystalline silicon solar cell during working can be further utilized and converted into electric energy, on the other hand, the working temperature of the solar cell can be reduced, and the output power can be improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:

FIG. 1 is a schematic structural diagram of an apparatus having photovoltaic power generation and thermoelectric power generation functions according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a device having photovoltaic power generation and thermoelectric power generation functions according to an embodiment of the present invention, wherein an external power source is connected to the electrodes.

Wherein the content of the first and second substances,

1. a front electrode; 2. an anti-reflection layer; 3. an N-type silicon layer; 4. a P-type silicon substrate; 5. a passivation layer; 6. a back electrode; 7. a thermally conductive connecting film; 81. a first ceramic layer; 82. a second ceramic layer; 91. a first conductor; 92. a second conductor; 10. bismuth telluride as P-type; 11. bismuth telluride as an N-type; 12. connecting an external power supply;

100. a first end; 200. a second end.

Detailed Description

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the advantages and features of the utility model may be more readily understood by those skilled in the art. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

As used herein, the terms "comprises" and "comprising" are intended to be inclusive and mean that there may be additional steps or elements other than the listed steps or elements. As used herein, the term "and/or" includes any combination of one or more of the associated listed items.

Referring to fig. 1, the present embodiment provides a device having photovoltaic power generation and thermoelectric power generation functions, including a solar cell and a thermoelectric power generation mechanism.

The solar cell comprises a reflection reducing layer 2, an N-type silicon layer 3, a P-type silicon substrate 4 and a passivation layer 5 which are sequentially stacked from top to bottom, the solar cell further comprises a front electrode 1 arranged on the reflection reducing layer 2, the front electrode 1 penetrates through the reflection reducing layer 2 and is in ohmic contact with the N-type silicon layer 3, and a back electrode 6 covers the passivation layer 5 and is in ohmic contact with the P-type silicon substrate 4 locally. The solar cell sheet is a PERC solar cell, and may be other types of solar cells, such as TOPCon, HJT, and the like.

The thermoelectric generation mechanism includes a first conductor 91 and a second conductor 92, and the first conductor 91 and the second conductor 92 are respectively copper, aluminum, copper alloy or aluminum alloy, and are capable of conducting electricity while conducting heat, and allowing holes and electrons to move to form a potential difference. A plurality of P-type semiconductor power generation elements and N-type semiconductor power generation elements are further provided at intervals between the first conductor 91 and the second conductor 92, and each of the P-type semiconductor power generation elements and the N-type semiconductor power generation elements has a plurality of first ends 100 closer to the rear surface electrode and a plurality of second ends 200 farther from the rear surface electrode. The P-type semiconductor power generation element is specifically P-type bismuth telluride 10, and the N-type semiconductor power generation element is specifically N-type bismuth telluride 11.

The thermoelectric generation mechanism further includes a first ceramic layer 81 and a second ceramic layer 82, the first ceramic layer 81 being provided on the back surface of the heat conductive connection film 7, the P-type semiconductor power generation element and the N-type semiconductor power generation element being located between the first ceramic layer 81 and the second ceramic layer 82, the first conductor 91 being connected or in contact with the first ceramic layer 81, and the second conductor 92 being connected or in contact with the second ceramic layer 82. Specifically, in the present embodiment, the first conductor 91 and the first ceramic layer 81 are connected to each other by a solder connection or a solid-phase connection, and the second conductor 92 and the second ceramic layer 82 are connected to each other by a solder connection or a solid-phase connection.

The device further comprises a heat conduction connection film 7, the back electrode 6 is arranged on the front face of the heat conduction connection film 7, the first ceramic layer 81 of the thermoelectric generation mechanism is arranged on the back face of the heat conduction connection film 7, and the heat conduction connection film 7 is used for bonding and connecting the back electrode 6 and the first ceramic layer 81. In the embodiment, the heat conductive connection film 7 is at least one of heat conductive silicone grease, heat conductive glue, liquid metal or a brazing layer.

In the working state, the temperatures of the first ceramic layer 81 and the second ceramic layer 82 are different, the working state includes a thermoelectric generation state and a refrigeration state, in the thermoelectric generation state, the first ceramic layer 81 is a hot end, and the second ceramic layer 82 is a cold end; the device has a refrigeration state, in which the first ceramic layer 81 is a cold end, the second ceramic layer 82 is a hot end, and conductors at the left and right ends are connected with the external power supply 12.

In the thermoelectric power generation state, the temperature of the solar cell rises, and heat energy is transferred to the heat conduction layer 7; the heat conduction layer 7 transfers heat energy to the first ceramic layer 81, and the first ceramic layer 81 is close to one end of the back electrode of the solar cell and has the working temperature close to that of the solar cell; the second ceramic layer 82 is located at a position away from the back electrode of the solar cell, and the operating temperature of the second ceramic layer is close to the ambient temperature. Therefore, the first ceramic layer 81 and the second ceramic layer 82 of the thermoelectric power generation mechanism generate temperature difference, and due to the fact that the hot end has strong thermal excitation effect and the concentration of holes and electrons is higher than that of the cold end, the holes and the electrons are diffused towards the cold end under the driving of the carrier concentration gradient, thermoelectric electromotive force is generated, and potential difference is formed. Every two adjacent P-type bismuth telluride 10 and N-type bismuth telluride 11 form a power generation unit, and because the potential difference formed by a single unit is very low, a multistage series connection mode is adopted: referring to fig. 1, in each power generation unit, P-type bismuth telluride 10 is connected to N-type bismuth telluride 11 through a first conductor 91; except for the leftmost power generating unit, each unit of P-type bismuth telluride 10 is connected to the previous unit of N-type bismuth telluride 11 by a second conductor 92. The P-type bismuth telluride 10 and the N-type bismuth telluride 11 are arranged in a staggered manner and are sequentially connected in series through the first conductor 91 and the second conductor 92, so that a multistage thermoelectric power generation mechanism can be formed.

As shown in fig. 2, in the cooling state, the conductors at the left and right ends of the device are respectively connected to an external power supply, at this time, the first ceramic layer 81 is a cold end, the second ceramic layer 82 is a hot end, and the external power supply 12 can make the device perform the reverse reaction of the above reaction, so as to greatly reduce the temperature of the side of the thermoelectric generation mechanism close to the solar cell, and reduce the operating temperature thereof.

According to the device with the photovoltaic power generation and thermoelectric power generation functions, the heat conduction connecting film 7 is arranged between the solar cells and the thermoelectric power generation mechanism which are connected with each other, so that the effects of buffering and bonding connection are achieved, local overheating can be avoided, and components are prevented from being damaged; the thermoelectric generation mechanism can further utilize heat energy generated by the solar cell during working and convert the heat energy into electric energy, so that the output power and efficiency of the whole device are improved, and on the other hand, the working temperature of the solar cell can be reduced, so that the working condition of components is stable; meanwhile, the thermoelectric generator can be used as a refrigerator when being connected with an external power supply, and the working temperature of the solar cell can be reduced when the solar cell is overheated.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and are preferred embodiments, which are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the scope of the present invention.

Claims

1. The device is characterized in that the device further comprises a heat-conducting connecting film, the back electrode is arranged on the front face of the heat-conducting connecting film, and the hot end of the thermoelectric generation mechanism is connected to the back face of the heat-conducting connecting film.

2. The device of claim 1, wherein the hot end is bonded to the back side of the back electrode by the thermally conductive connecting film.

3. The device according to claim 1 or 2, wherein the heat-conducting connecting film is any one of heat-conducting silicone grease, heat-conducting glue, liquid metal or brazing layer; and/or the heat conduction connecting film completely covers the surface of the back electrode or the front surface of the hot end.

4. The apparatus according to claim 1, wherein the thermoelectric generation mechanism includes a P-type semiconductor power generation element and an N-type semiconductor power generation element having a first end closer to the back surface electrode and a second end farther from the back surface electrode, respectively; the thermoelectric generation mechanism further comprises a first conductor for connecting the first end of the P-type semiconductor element and the first end of the N-type semiconductor element in a conduction manner.

5. The device according to claim 4, wherein the thermoelectric generation mechanism further comprises a first ceramic layer and a second ceramic layer, the first ceramic layer is provided on the back surface of the thermally conductive connection film, the P-type semiconductor power generation element and the N-type semiconductor power generation element are located between the first ceramic layer and the second ceramic layer, and the first conductor is connected to or in contact with the first ceramic layer.

6. The apparatus according to claim 5, wherein the thermoelectric generation mechanism further comprises a second conductor for conductively connecting the second end of the P-type semiconductor element and the second end of the N-type semiconductor element, at least the P-type semiconductor generation element is plural in number, or at least the N-type semiconductor generation element is plural in number, and the P-type semiconductor generation element and the N-type semiconductor generation element are alternately arranged and are sequentially connected in series through the first conductor and the second conductor.

7. The device of claim 6, wherein the first ceramic layer and the second ceramic layer are each an alumina ceramic; and/or the first conductor and the second conductor are respectively copper, aluminum, copper alloy or aluminum alloy; and/or the P-type semiconductor power generation element is a P-type bismuth telluride semiconductor, and the N-type semiconductor power generation element is an N-type bismuth telluride semiconductor.

8. The device of claim 6, further comprising an external power source, wherein the device has a thermoelectric generation state and a cooling state for cooling the solar cell, and in the thermoelectric generation state, the external power source is turned off, and the temperature of the hot end is higher than that of the cold end; in the refrigeration state, the external power supply supplies power to the temperature difference power generation device, and the temperature of the hot end is lower than that of the cold end.

9. The device of claim 1, wherein the solar cell is a PERC cell, a TOPCon cell, or an HJT cell.

10. The device of claim 1, wherein the solar cell comprises an anti-reflection layer, an N-type silicon layer, a P-type silicon substrate and a passivation layer which are sequentially stacked from top to bottom, the solar cell further comprises a front electrode disposed on the anti-reflection layer, the front electrode penetrates through the anti-reflection layer and is in ohmic contact with the N-type silicon layer, and the back electrode covers the passivation layer and is partially in ohmic contact with the P-type silicon substrate.