CN212062448U

CN212062448U - Photovoltaic module

Info

Publication number: CN212062448U
Application number: CN202020642702.0U
Authority: CN
Inventors: 荣丹丹; 蒋京娜; 张颖; 倪健雄; 姜磊; 耿亚飞; 李亚彬
Original assignee: Yingli Energy China Co Ltd
Current assignee: Dali Yingli New Energy Co ltd
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2020-12-01
Anticipated expiration: 2030-04-24

Abstract

The utility model provides a photovoltaic module belongs to photovoltaic power generation technical field, including the battery base plate, the battery base plate includes: the battery pack includes a first battery cell, a second battery cell, and a third battery cell connected in series, a first bypass diode connected in parallel with the first battery cell, and a second bypass diode connected in parallel with the second battery cell and the third battery cell. The utility model provides a photovoltaic module only sets up two bypass diodes, has simplified the circuit connection structure, has reduced the flow of photovoltaic module preparation, has improved work efficiency, eliminates the hot spot effect through the bypass diode simultaneously, has reduced the output loss, has improved photovoltaic module's output.

Description

Photovoltaic module

Technical Field

The utility model belongs to the technical field of photovoltaic power generation, more specifically say, relate to a photovoltaic module.

Background

The existing photovoltaic module is connected in series and parallel by using a whole battery, the specification and the size of the battery are fixed, the requirements of different photovoltaic systems on the size of the battery and the output current and voltage cannot be met, the working current of the battery is large, the resistance loss of a welding strip and a converging strip is also large, and the internal power loss of the photovoltaic module is large. The battery piece scribing technology is a good mode for improving the power of the assembly, large-size battery pieces are scribed, and small battery pieces subjected to scribing are connected in series and in parallel, so that the internal loss of the assembly can be effectively reduced, and the current and voltage requirements of high-power output and different photovoltaic systems on the assembly are met.

At present, large-size battery pieces become mainstream, and the 166-210-size battery pieces have larger power improvement on the assembly, but the circuit design of the assembly needs to meet the requirements of a conventional system and the container of the assembly.

The method for improving the power of the assembly is to enlarge the size of a battery and design scribing, and respectively improve the power of the assembly in the aspects of electricity and optics.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a photovoltaic module through reasonable connecting circuit, reduces the quantity of diode, solves because the quantity of diode is many and causes the problem that the operation is complicated.

In order to achieve the above object, the utility model adopts the following technical scheme: there is provided a photovoltaic module comprising a cell substrate, the cell substrate comprising: the battery pack includes a first battery cell, a second battery cell, and a third battery cell connected in series, a first bypass diode connected in parallel with the first battery cell, and a second bypass diode connected in parallel with the second battery cell and the third battery cell.

As another embodiment of this application, first battery unit includes four battery strings, four two liang of battery strings establish ties to be two sets of group battery, two sets of group battery connect in parallel and constitute first battery unit, the structure of second battery unit with first battery unit's structure is the same, the third battery unit includes two parallelly connected battery strings.

As another embodiment of the present application, a negative terminal of the first bypass diode is connected to a positive terminal of the first battery unit, and a positive terminal of the first bypass diode is connected to a negative terminal of the first battery unit;

and the negative end of the second bypass diode is connected with the positive electrode of the second battery unit, and the positive end of the second bypass diode is connected with the negative end of the third battery unit.

As another embodiment of this application, first battery unit includes four battery strings, four two liang parallelly connected battery strings are two sets of group batteries, two sets of group batteries establish ties and constitute first battery unit, the structure of second battery unit with first battery unit's structure is the same, the third battery unit includes two parallelly connected battery strings.

and the negative end of the second bypass diode is connected with the positive electrode of the third battery unit, and the positive end of the second bypass diode is connected with the negative end of the second battery unit.

As another embodiment of the application, the battery string comprises a plurality of small battery pieces which are connected in series, and two adjacent small battery pieces are connected through a welding strip.

As another embodiment of the present application, a split junction box is respectively disposed outside the first bypass diode and the second bypass diode.

As another embodiment of the present application, the photovoltaic module further includes an upper cover glass, an encapsulation material, and a lower cover glass for encapsulating the cell substrate.

As another embodiment of the present application, the surfaces of the upper cover glass and the lower cover glass are provided with a reflective layer.

As another embodiment of the present application, the reflective layer is a reflective film or a glaze-coated layer.

The utility model provides a photovoltaic module's beneficial effect lies in: compared with the prior art, the utility model discloses photovoltaic module with the battery cell who divide into three series connection on the battery substrate, the parallelly connected bypass diode of one of them battery cell, the parallelly connected bypass diode of two remaining battery cells, whole battery substrate only sets up two bypass diodes, has simplified circuit connection structure greatly, has reduced the flow of photovoltaic module preparation, has improved work efficiency, eliminates the hot spot effect through the bypass diode simultaneously, has reduced the output loss, has improved photovoltaic module's output.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a first schematic structural diagram of a photovoltaic module according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a circuit connection structure of the photovoltaic module provided in FIG. 1;

fig. 3 is a schematic structural diagram ii of a photovoltaic module according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a circuit connection structure of the photovoltaic module shown in FIG. 3;

fig. 5 is a schematic structural view of the photovoltaic module package according to an embodiment of the present invention.

In the figure: 1. a battery string; 2. a first bypass diode; 3. a second bypass diode; 4. upper cover glass; 5. packaging materials; 6. a battery substrate; 7. a lower cover glass; 8. a first battery cell; 9. a second battery cell; 10. and a third battery cell.

Detailed Description

In order to make the technical problem, technical solution and advantageous effects to be solved by the present invention more clearly understood, the following description is given in conjunction with the accompanying drawings and embodiments to illustrate the present invention in further detail. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1 to 4, a photovoltaic module according to the present invention will now be described. The photovoltaic module comprises a cell substrate 6, wherein the cell substrate 6 comprises: a first battery cell 8, a second battery cell 9 and a third battery cell 10 connected in series, a first bypass diode 2 connected in parallel with the first battery cell 8, and a second bypass diode 3 connected in parallel with the second battery cell 9 and the third battery cell 10.

The utility model provides a photovoltaic module, compared with the prior art, divide into the battery cell of three series connection on the battery substrate 6, a bypass diode that one of them battery cell is parallelly connected, a bypass diode that two remaining battery cells are parallelly connected, whole battery substrate 6 only sets up two bypass diodes, the circuit connection structure has been simplified greatly, the flow of photovoltaic module preparation has been reduced, the work efficiency is improved, hot spot effect is eliminated through the bypass diode simultaneously, the output loss is reduced, photovoltaic module's output has been improved.

As a specific embodiment of the photovoltaic module provided in the present invention, please refer to fig. 1 to fig. 2, the first battery unit 8 includes four battery strings 1, four two sets of battery strings 1 are connected in series to form two sets of battery packs, the two sets of battery packs are connected in parallel to form the first battery unit 8, the structure of the second battery unit 9 is the same as that of the first battery unit 8, and the third battery unit 10 includes two parallel battery strings 1.

In this embodiment, the battery string 1 includes a plurality of dicing battery pieces connected in parallel, the dicing battery pieces are obtained by cutting a large-size crystalline silicon battery piece of a traditional standard specification into small battery pieces of various specifications such as 1/2, 1/3 or 1/4 by a laser cutting process, then interconnecting the small battery pieces into the battery string 1, and then connecting the battery string 1 in series and parallel. Such a photovoltaic module has the following advantages: (1) the internal series resistance loss of the assembly can be effectively reduced, and the power of the assembly is improved by matching with a special-shaped welding strip and a reflective material; (2) the method has the characteristics of better suitability for high current and high voltage of large-size battery plates, and is suitable for conventional systems; (3) the conventional photovoltaic module is provided with three or more than three diodes, the embodiment is designed into two diodes, the operation procedures are reduced, and the module manufacturing method is simultaneously suitable for single-side and double-side power generation modules.

As a specific implementation manner of the embodiment of the present invention, please refer to fig. 2, a negative terminal of the first bypass diode 2 is connected to a positive electrode of the first battery unit 8, and a positive terminal is connected to a negative electrode of the first battery unit 8; the negative end of the second bypass diode 3 is connected with the positive electrode of the second battery unit 9, and the positive end is connected with the negative end of the third battery unit 10.

As a specific implementation manner of the embodiment of the present invention, referring to fig. 3 and fig. 4, the first battery unit 8 includes four battery strings 1, four two pairs of the battery strings 1 are connected in parallel to form two sets of battery packs, the two sets of battery packs are connected in series to form the first battery unit 8, the structure of the second battery unit 9 is the same as that of the first battery unit 8, and the third battery unit 10 includes two parallel battery strings 1.

As a specific implementation manner of the embodiment of the present invention, please refer to fig. 3 to 4, wherein a negative terminal of the first bypass diode 2 is connected to a positive terminal of the first battery unit 8, and a positive terminal is connected to a negative terminal of the first battery unit 8; the negative end of the second bypass diode 3 is connected with the positive electrode of the third battery unit 10, and the positive end is connected with the negative end of the second battery unit 9.

As a specific implementation of the embodiment of the utility model, battery cluster 1 includes a plurality of series connection continuous little battery pieces, adjacent two connect through welding the area between the little battery piece. Circular solder strip, triangle solder strip, semicircular solder strip improve the light absorption area and the light absorption performance of battery piece.

As a specific implementation manner of the embodiment of the present invention, the first bypass diode 2 and the outside of the second bypass diode 3 are respectively provided with a split type junction box. The embodiment only needs to provide two junction boxes, thereby reducing the complexity of operation and simultaneously avoiding the problem that the number of the junction boxes and the bypass diodes is too much and the space is difficult to arrange.

As a specific implementation manner of the embodiment of the present invention, please refer to fig. 5, the photovoltaic module further includes an upper cover glass 4, a packaging material 5, and a lower cover glass 7 for packaging the battery substrate 6.

As a specific implementation manner of the embodiment of the present invention, the surface of the upper cover glass 4 and the lower cover glass 7 is provided with a reflective layer. The light absorption of the battery can be increased by increasing the distance between the assembly battery strings 1, so that the assembly power is increased, or the light absorption capacity of the assembly can be increased by sticking a reflective film on a back plate and glass or by glazing the glass.

As a specific implementation manner of the embodiment of the utility model, the reflective layer is a reflective film or a glaze-coated layer.

The manufacturing process of this embodiment is as follows:

the method comprises the following steps: and cutting the large battery piece with single-side or double-side power generation into a plurality of small-size battery pieces by adopting a laser scribing mode. The side length of the cut small cell is 1/n (n is 2, 3, 4 and the like) of the large cell, so that the specification and the model of the cell can meet the requirements of different output voltages and sizes. The double-sided solar cell sheet is a cell capable of absorbing sunlight on two sides, and includes but is not limited to a p-type double-sided power generation solar cell and an n-type double-sided power generation solar cell.

And connecting the diced small-sized battery pieces in series to form a battery string, and connecting two adjacent battery strings in series or in parallel to form the structure shown in the figures 1 and 3.

Step two: and connecting the cut scribing batteries in series to form a battery string, and then designing a circuit. There are two main circuit connection modes, scheme one: referring to fig. 1, the battery strings may be connected in series and then in parallel; scheme II: referring to fig. 3, the battery strings are connected in parallel and then in series. The two connection modes can ensure that the output voltage and current of the single-sided or double-sided power generation assembly are close to the output voltage and current of the conventional assembly, and the system end assembly is convenient to use. The interconnecting material can be metal solder strips and conductive adhesive tapes. If the metal welding strip is a metal welding strip, the metal welding strip can be a circular welding strip, a triangular welding strip or a semicircular welding strip, so that the battery piece can obtain more light absorption. The problem that the current of the large-size battery piece is high is combined, the small battery pieces are adopted for welding design, so that the parameter output of the component is suitable for the use of the existing system, the circuit design can be divided into a vertical plate design and a horizontal plate design, 2 bypass diodes are adopted, the hot spots of the component are prevented from being generated, and the component is suitable for a single-side power generation component and a double-side power generation component.

The specific connection mode can be as follows:

the first scheme is as follows: the battery strings are connected in series and then connected in parallel, and the junction box adopts two small split type junction boxes or one junction box. The number of battery pieces and the number of battery strings of each battery unit are designed according to the large-size battery piece, for example, the 210-size battery piece is divided into three small battery pieces of 70 × 210mm through 1/3 scribing, each battery string is 15 small battery pieces, and the total number of battery pieces is 150, as shown in fig. 1.

FIG. 1 is a schematic circuit layout diagram of a plate module, the circuit connection is as shown in FIG. 2, a large-size cell is cut into 1/3 small cells by laser scribing, the small cells are welded by a welding belt, 15 small cells are welded into small strings, the upper half portion is 5 cell strings in total, 75 small cells are in total, the 5 small strings of the upper half portion are connected in series, the 5 small strings of the same lower half portion are connected in series, finally the upper half portion and the lower half portion are connected in parallel, the output power is output, the photovoltaic module is provided with 2 bypass diodes in total, the left three symmetric cell strings are connected in parallel by a lead, the upper and lower six small strings of cell strings are protected by the bypass diodes, the two small strings on the right side are connected in parallel by a bypass diode, the bypass diodes protect the upper and lower small strings, the bypass diodes play a role in protecting the power output of the battery string under the condition of hot spots, the two bypass diodes only need to be provided with two small split type junction boxes, and in the subsequent operation process, only workers need to install two box bodies, so that the problem that the middle junction box is inconvenient to operate in the installation process of the three-split junction box is solved.

Scheme II: every two small strings of the battery string are firstly connected in parallel, and finally all the two strings are connected in series, and the junction box adopts two small split junction boxes or one junction box. The number of the battery pieces and the number of the battery strings of each string are designed according to the large-size battery pieces, for example, the 210-size battery pieces are divided into three small battery pieces of 70 × 210mm by 1/3 dicing, each battery string is 15 small battery pieces, and the total number of the battery pieces is 150, as shown in fig. 3.

FIG. 3 is a schematic circuit layout diagram of a plate module, the circuit connection is as shown in FIG. 4, a large-size cell is cut into 1/3 small cells by laser scribing, the small cells are 70X 210mm, the small cells are welded by welding strips, wherein 15 small cells are welded into cell strings, each two cell strings are welded in parallel by interconnection strips to form 5 parallel small plates, the 5 parallel small plates are sequentially connected in series, finally, the power output is carried out by the 1 st parallel small plate and the 5 th parallel small plate, the two left parallel small plates are connected in parallel with a bypass diode, the three right parallel small plates are connected in parallel with a bypass diode by leads to form 2 bypass diodes, only two small split junction boxes need to be installed on the two bypass diodes, and in the subsequent operation process, only two box bodies need to be installed by a worker, the problem that the middle junction box is inconvenient to operate in the installation process of the three-split junction box is solved.

And thirdly, paving the upper cover glass 4, the packaging material 5, the battery substrate 6, the packaging material 5, the lower cover glass 7 or the back plate in sequence with reference to the figure 5. The laying process of the module in the manufacturing process needs to be noticed that the absorption of the battery to light can be increased by increasing the distance between the module battery strings, so that the module power is increased, or the module light absorption capacity can be increased by sticking a reflective film on a back plate and glass or by glazing glass. After the optimized component materials are matched and manufactured according to the processes of welding, laying, laminating and framing, according to simulation data, the 210 mm-sized cell piece with 22.8% of photoelectric conversion efficiency is subjected to 1/3 scribing to form a small cell piece with the size of 70 x 210mm, after the small cell piece is arranged in a vertical plate or horizontal plate mode, the power of the photovoltaic component reaches 500W, and the component packaging loss is low.

In general, the loss of glass in optical loss in the packaging process of the module is about 4%, so that the use of the reflective material in the cell string interval has an effect of improving the CTM. Experiments show that the power is increased by 3-5W by adopting components of the glazed glass or materials such as a reflective film, the CTM improves the short-circuit current to be in direct proportion to the light intensity, and the gain of the light intensity is converted into the short-circuit current, so that the power is improved. The encapsulating material 5 may be EVA, POE, or the like. Among them, EVA is an ethylene-vinyl acetate (vinyl acetate) ester copolymer, which is prepared by copolymerizing ethylene (E) and Vinyl Acetate (VA), having english name: ethylene vinyl acetate, abbreviated EVA; POE (Polyolyyaltha olfin) polyethylene octene co-elastomer.

The CTM value (Cell To Module) is the percentage of the sum of the output power of the component and the power of the battery Cell, and represents the degree of the power loss of the component, and the higher the CTM value is, the smaller the degree of the power loss of the component package is.

Step four: and (4) after laying, performing an EL test, and entering a laminating machine for laminating to prepare the single-sided or double-sided solar cell module laminating piece.

Among them, the EL tester is called an electroluminescence (english electroluminescence) tester, and is an internal defect detecting device for a solar cell or a battery module. The method is commonly used for detecting internal defects, hidden cracks, fragments, insufficient soldering, broken grids and abnormal phenomena of single cells with different conversion efficiencies of the solar cell module.

Step five: the junction box can be installed according to requirements, a frame can be installed, the mechanical resistance of the assembly is improved through the main effect of the aluminum material, and the photovoltaic assembly is prevented from being hidden and cracked in the transportation and installation process.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims

1. A photovoltaic module comprising a cell substrate, said cell substrate comprising:

a first battery cell, a second battery cell, and a third battery cell connected in series;

a first bypass diode connected in parallel with the first battery cell;

a second bypass diode connected in parallel with the second battery cell and the third battery cell.

2. The photovoltaic module according to claim 1, wherein the first battery unit comprises four battery strings, four battery strings are connected in series two by two to form two battery packs, the two battery packs are connected in parallel to form the first battery unit, the second battery unit has the same structure as the first battery unit, and the third battery unit comprises two battery strings connected in parallel.

3. The photovoltaic module of claim 2, wherein the negative terminal of the first bypass diode is connected to the positive terminal of the first cell and the positive terminal is connected to the negative terminal of the first cell;

4. The photovoltaic module according to claim 1, wherein the first battery unit comprises four battery strings, four of the battery strings are connected in parallel two by two to form two battery packs, the two battery packs are connected in series to form the first battery unit, the second battery unit has the same structure as the first battery unit, and the third battery unit comprises two battery strings connected in parallel.

5. The photovoltaic module of claim 4, wherein the negative terminal of the first bypass diode is connected to the positive terminal of the first cell and the positive terminal is connected to the negative terminal of the first cell;

6. The photovoltaic module according to any one of claims 2 to 5, wherein the cell string comprises a plurality of small cells connected in series, and two adjacent small cells are connected by a solder ribbon.

7. The photovoltaic module according to claim 1, wherein a split junction box is respectively arranged outside the first bypass diode and the second bypass diode.

8. The photovoltaic module of claim 1, further comprising an upper cover glass, an encapsulant, and a lower cover glass for encapsulating the cell substrate.

9. The photovoltaic module of claim 8, wherein the surfaces of the upper cover glass and the lower cover glass are provided with a light reflecting layer.

10. The photovoltaic module of claim 9, wherein the light reflecting layer is a light reflecting adhesive film or a glazing layer.