CN104835874B - A kind of manufacture method of half-cell piece photovoltaic module - Google Patents

Abstract

A kind of manufacture method of half-cell piece photovoltaic module, belongs to photovoltaic cell field, and the manufacturing step of photovoltaic module is as follows：A. the size of solar battery sheet is processed into 125mm × 62.5mm or solar battery sheet 156mm × 78mm respectively, and welding electrode, form half solar battery sheet, B. connected mode, C. combination, D. laminating machine is utilized in the laminated multilayer laminated film of cover plate film, the line between half-cell piece and half-cell piece is set to be isolated from the outside, E. sealed in connection jaws encapsulating, the both positive and negative polarity of battery component is connected on binding post, F. frame is assembled, the method peak power can improve 3% 6%.

Description

A method of manufacturing a half-cell photovoltaic module

technical field

The invention relates to a method for manufacturing a photovoltaic module, in particular to a method for manufacturing a half-cell photovoltaic module, and belongs to the field of photovoltaic cells.

Background technique

As the world's energy crisis and environmental pollution become more and more serious, relevant personnel have accelerated the research on solar photovoltaic power generation technology and promoted the development of solar photovoltaic cell and module manufacturing technology. At present, the photovoltaic modules that account for more than 90% of the market share are crystalline silicon photovoltaic cell modules. In the battery industry, generally in the connection of battery components, the battery slices in the same row or column are connected in series to form a small string, and then two adjacent small strings are connected in parallel to be called a middle string, and then all the middle strings are connected in series Or the string formed after parallel connection is called a large string, and this name can also be used for the connection of cells in a module. However, the crystalline silicon solar cell photovoltaic cell module is mainly to arrange several cells of this specification in a matrix (for example, 6 columns*10 rows=60 pieces, 8 columns*12 rows=96 pieces, etc.) and then package them in series. The structure of leading the positive and negative poles out of the junction box, the output power of the solar photovoltaic module with this structure is stable at a certain value, basically there is not much difference. However, from the current status quo, the conversion efficiency of solar photovoltaic modules is still at a relatively low stage. Compared with the theoretical conversion efficiency, there is a certain gap. How to improve the output power of photovoltaic modules per unit area is the industry has been working hard At present, the solar photovoltaic cell industry mainly adopts the following two methods to improve conversion efficiency, one is to improve the conversion efficiency of a single cell, and the other is to minimize the power loss caused by packaging factors. In addition, since solar cells are made of semiconductor silicon, after cutting, grinding, texturing, diffusion, etching, anti-reflection, printing, drying, sintering and other mechanical processing and high-temperature treatment processes, during the manufacturing process of solar cells, Although we try our best to release the stress, there will still be some stress in some positions. During the manufacturing process, due to equipment or human factors, solar photovoltaic cells will be damaged due to certain angles. It is judged as unqualified products. For these products, because the price of silicon products is very expensive, it is a pity to discard the entire cell based on this alone, because this cell can still play the role of power generation. If this part of solar photovoltaic cells Making full use of it can play a certain role in reducing costs and increasing benefits for enterprises. In the package power loss, the power loss of the component itself due to the existence of the internal resistance of the component accounts for a large part. In the composition of the internal resistance of photovoltaic modules, the internal resistance of the battery sheet occupies the main part and remains basically unchanged. If the current passing through the battery sheet is reduced by half, then according to Joule's law, the internal resistance power loss will be reduced by a quarter. .

Contents of the invention

Aiming at the current situation that the photoelectric conversion rate of solar photovoltaic modules is relatively low and the expensive defective solar cells cannot be fully utilized, the present invention provides a method for manufacturing half-cell photovoltaic modules, the purpose of which is to improve the photoelectric conversion rate of solar cells, Use partially damaged solar cells to generate electricity and improve the utilization rate of silicon wafers.

The technical solution of the present invention is: a method for manufacturing a half-cell photovoltaic module, including arranging a substrate of a solar cell, and the half-cell photovoltaic module includes the following manufacturing steps:

A． The size of the solar cell is processed into 125mm×62.5mm or 156mm×78mm respectively, and the electrodes are welded to form a half cell;

B． Connect the half-cells on the substrate according to any of the following connection methods:

B1. The half-cells in the entire solar cell module are connected in series, including the series connection method in the order of rows/columns;

B2. Half of the half-cells in the entire solar cell module are connected in series in rows/columns, and the other half are connected in parallel in rows/columns, including the upper and lower halves divided along the transverse midline and along the longitudinal direction. The left and right half-cells divided by the midline, the number of the upper and lower halves or the left and right half-cells is equal;

B3. In the entire solar cell module, after each column/row is connected in series, two adjacent columns/rows are connected in parallel to form a middle string, and the parallel connected middle string is connected in series with other middle strings again to form a large string;

C． In order to achieve the connection methods in B1, B2 and B3, the matrix arrangement of the half-cells can be divided into the following types, and one of the connection methods in the above step B can be realized according to any one of the matrix arrangements:

C1. The length and width directions of the half-cells are aligned with the length and width directions of the substrate;

C2. The length and width directions of the half-cells are arranged perpendicular to the length and width directions of the substrate;

C3. The electrode directions of odd-numbered columns/rows and even-numbered columns/rows of the half-cell sheets are opposite;

C4. The module is divided into left and right parts with the centerline of the width of the substrate as the axis of symmetry, and the electrode directions of the odd-numbered and even-numbered columns of half-cells in each part are opposite;

C5. The assembly is divided into upper and lower parts with the center line of the length of the substrate as the axis of symmetry, and the electrode directions of the odd-numbered and even-numbered columns of half-cells in each part are opposite;

C6. The component is divided into two symmetrical parts with the center line of the width of the substrate as the axis of symmetry. The electrodes of the two adjacent columns on the outermost side of each part have the same electrode direction, and if there is a third column, the electrode direction of the third column is opposite.

Further, the number of arrangement of the half-cells in the module is X columns × Y rows = N pieces, where X is the number of matrix columns, Y is the number of matrix rows and X and Y are both positive integers, and satisfy 8≤X≤ 16. 12≤Y≤24, X≤Y,

Furthermore, the half-cells include monocrystalline silicon cells, polycrystalline silicon cells, crystalline silicon heterojunction cells, interdigitated back contact cells, and emitter through-hole wound cells.

The manufacturing method in this invention uses half-cells whose available size is half of the cell size of 125mm×125mm or 156mm×156mm in the prior art, so that some of the discarded cells in the prior art can be fully utilized and become waste. Weibao, by regularly combining several half-cells in series and parallel according to the positive and negative directions, and finally packaging them together to form the half-cell photovoltaic module, can effectively reduce the self-power loss caused by the internal resistance of the photovoltaic module , so as to improve the power output of photovoltaic modules. Compared with the combination of existing battery sheets, the maximum power can be increased by 3%-6% by using this half-cell combination, and a higher photoelectric conversion rate is achieved.

Description of drawings

Accompanying drawing 1 is the schematic diagram of solar crystalline silicon cells of the prior art.

Accompanying drawing 2 is a schematic diagram of a half cell.

Accompanying drawing 3 is a schematic diagram of prior art components arranged in 4 columns x 9 rows of 36 complete cells of the prior art.

Figure 4 is a schematic diagram of a half-cell assembly in which 72 half-cells are arranged in 4 columns x 18 rows and connected in series first, then in parallel and then in series.

Figure 5 is a schematic diagram of a half-cell assembly in which 72 half-cells are arranged in 4 columns x 18 rows, and the connection mode is that the left and right parts are connected in series respectively, and then the left and right parts are connected in parallel.

Figure 6 is a schematic diagram of a half-cell assembly in which 72 half-cells are arranged in 4 columns x 18 rows, and the connection mode is that the upper and lower parts are connected in series respectively, and then the upper and lower parts are connected in parallel.

Accompanying drawing 7 is a schematic diagram of prior art components arranged in 5 columns×10 rows of 50 complete cells of the prior art.

Figure 8 is a schematic diagram of a half-cell assembly in which 100 half-cells are arranged in 10 columns×10 rows and connected in series first, then parallel and then in series.

Accompanying drawing 9 is a schematic diagram of prior art components arranged in 6 columns×10 rows of 60 complete cells of the prior art.

Figure 10 is a schematic diagram of a half-cell assembly in which 120 half-cells are arranged in 6 columns x 20 rows and connected in series, then parallel, and then in series.

Figure 11 is a schematic diagram of a half-cell assembly in which 120 half-cells are arranged in 6 columns x 20 rows, and the connection mode is that the left and right parts are connected in series respectively, and then the left and right parts are connected in parallel.

Figure 12 is a schematic diagram of a half-cell assembly in which 120 half-cells are arranged in 6 columns x 20 rows, and the connection mode is that the upper and lower parts are connected in series respectively, and then the upper and lower parts are connected in parallel.

detailed description

In order to better understand the present invention, a specific implementation is provided in conjunction with the accompanying drawings, and the present invention is not limited to the specific embodiment.

Referring to Fig. 1-Fig. 12, the technical solution of the present invention will be described in detail. In the figure, 100: solar cell, 200: half-cell, 101: prior art solar cell anode, 102: prior art solar energy Cell negative pole, 201: half-cell positive pole, 202: half-cell negative pole, Fig. 3, Fig. 7, Fig. 9 are the solar cell modules connected in series with different numbers of cells in the prior art, among them, 301: 36 pieces Positive electrode after series connection of cells, 302: negative electrode after connection of 36 cells in series, 701: positive electrode after connection of 50 cells in series, 702: negative electrode after connection of 50 cells in series, 901: 60 cells The positive electrode after series connection, 902: the negative electrode after 60 cells are connected in series, Figure 4 and Figure 10 are the semi-solar battery modules that connect two adjacent small series in parallel and then align them in series again, among them, 401: 72 pieces Positive electrode assembled with half cells, 402: Negative electrode assembled with 72 half cells, 1001: Positive electrode assembled with 120 half cells, 1002: Negative electrode assembled with 120 half cells. Figure 8 shows the After the two adjacent rows of small series are connected in parallel, the half-cell components in series in the row are connected again, among which, 801: the positive electrode after assembling 100 half-cells, 802: the negative electrode after assembling 100 half-cells, Fig. 5, Fig. 6, Fig. 11. Figure 12 is an assembly drawing where half of the half-cells in the module are connected in series and then connected in parallel with the other half. Among them, 501: the positive electrode assembled with 72 half-cells, and 502: the negative electrode assembled with 72 half-cells , 601: positive electrode assembled with 72 half-cells, 602: negative electrode assembled with 72 half-cells 1101: positive electrode assembled with 120 half-cells, 1102: negative electrode assembled with 120 half-cells, 1201: Negative electrode assembled with 120 half-cells, 1202: positive electrode assembled with 120 half-cells.

A method for manufacturing a photovoltaic module, comprising setting a substrate of a solar cell, and the manufacturing steps of the photovoltaic module are as follows:

A． The size of the solar cell is processed into 125mm×62.5mm or 156mm×78mm respectively, and the electrodes are welded to form a half cell, that is to say, the size used in this invention is the size of the prior art cell size 125mm×125mm or 156mm×156mm half of the half-cell, therefore, it is called a half-cell in the present invention;

B． When the half-cells are arranged on the substrate, there are multiple connection methods. When connecting the half-cells of the photovoltaic module, the half-cells can be connected according to any one of the following connection methods:

B1. The half-cells in the entire solar cell module are connected in series, including the series connection method in the order of rows/columns. Most of the prior art adopts this overall series connection method. Among them, Fig. 3, Fig. 7, Figure 9 utilizes this overall series connection method, and is a structural diagram of connecting the positive electrode 101 of the battery sheet 100 in the prior art with the negative electrode 102 of another solar cell sheet in the prior art, wherein 301 is the structure shown in Figure 3 36 batteries are connected in series, 302 is the negative electrode of 36 batteries in Figure 3, 701 is the positive electrode of 50 batteries in Figure 7, 702 is 50 batteries in Figure 7 The negative electrode after series connection, 901 is the positive electrode after 60 battery pieces are connected in series in Figure 9, and 902 is the negative electrode after 60 battery pieces are connected in series in Figure 9;

B2. Half of the half-cells in the entire solar cell module are connected in series in rows/columns, and the other half are connected in parallel in rows/columns, including the upper and lower halves divided along the transverse midline and along the longitudinal direction. The left and right half-cells divided by the center line, the number of the upper and lower halves or the left and right half-cells is equal; among them, Fig. 5 and Fig. 11 take the center line of the horizontal side as the axis of symmetry of the assembly, first The assembly diagram of connecting half and a half of the cells in the left and right parts in series and then paralleling the other half. Figure 6 and Figure 12 are the assembly with the center line of the longitudinal side as the axis of symmetry, and the half and a half of the cells in the upper and lower parts are connected in series first. After connecting with the other half in parallel, 601 is the positive electrode assembled with 72 half cells in Figure 6, 602 is the negative electrode assembled with 72 half cells in Figure 6, and 1101 is the 120 cells in Figure 11 The positive electrode after the assembly of the half cells, 1102 is the negative electrode after the assembly of 120 half cells in Figure 11, 1201 is the negative electrode after the assembly of the 120 half cells in Figure 12, and 1202 is the assembly of the 120 half cells in Figure 12 the positive pole;

B3. Each column/row in the entire solar cell module is connected in series and then two adjacent rows/columns are connected in parallel, and the middle string after parallel connection is connected in series with other middle strings again to form a large string; The half-solar battery modules that are connected in parallel with the small series in the columns and then connected in series in the middle series again. Figure 8 is the half-solar battery module that connects the small series in every two rows in parallel and then aligns the series in series again. 401 is the assembly of 72 half-cells in Figure 4 Positive electrode, 402 is the negative electrode after assembling 72 half cells in Fig. 4, 1001 is the positive electrode after assembling 120 half cells in Fig. 10, 1002 is the negative electrode after assembling 120 half cells in Fig. 10, 801 is the 8 is the positive electrode assembled by 100 half-cells, and 802 is the negative electrode assembled by 100 half-cells in Figure 8;

C． In order to achieve the connection methods in B1, B2 and B3, the matrix arrangement of the half-cells can be divided into the following arrangements, and one of the connection methods in the above step B can be realized according to any one of the matrix arrangements:

C1. The length and width direction of the half-cell is aligned with the length and width direction of the substrate, and Figure 8 belongs to the photovoltaic module of this half-cell;

C2. The length and width of the half-cells are arranged vertically to the length and width of the substrate, and Figures 4, 5, 6, 10, 11, and 12 belong to photovoltaic modules of such half-cells;

C3. The electrode directions of odd columns/rows and even columns/rows of the half-cell matrix are opposite, wherein Figure 6 and Figure 12 belong to photovoltaic modules of this type of half-cell;

C4. The module is divided into two symmetrical parts with the midline of the width of the substrate as the axis of symmetry, and the electrode directions of the odd and even columns of the half-cells in each part are opposite. Figure 5 and Figure 11 also belong to this type of half-cell photovoltaic module ;

C5. Taking the midline of the substrate as the axis of symmetry, the module is divided into two parts that are symmetrical up and down. The electrodes of the odd-numbered and even-numbered columns of the half-cells in each part are in opposite directions. Figure 6 and Figure 12 are photovoltaic modules of this type of half-cells ;

C6. The component is divided into two symmetrical parts with the centerline of the width of the substrate as the axis of symmetry. The electrode directions of the two adjacent columns on the outermost side of each part are the same. If there is a third column, the electrode direction of the third column is opposite, as shown in Figure 4 and Figure 10 is a photovoltaic module belonging to this type of half-cell;

D． Use a laminator to laminate a multi-layer laminated film on the cover glass, and combine it with the substrate assembled with half-cells, so that the half-cells and the connection between the half-cells are isolated from the outside world;

E． Fill the terminal port with glue to seal it, and connect the positive and negative poles of the battery pack to the terminals;

F． Assemble the border,

Further, the number of arrangement of the half-cells in the assembly is X columns × Y rows = N pieces, where X is the number of matrix columns, Y is the number of matrix rows and X and Y are both positive integers, and 8≤ X≤16, 12≤Y≤24, X≤Y conditions,

Furthermore, the half-cells include monocrystalline silicon cells, polycrystalline silicon cells, crystalline silicon heterojunction cells, interdigitated back contact cells, metal perforated wound cells, emitter perforated wound cells .

Example 1

Select the solar battery sheet 100 in the prior art, divide the middle of the solar battery sheet 100 in the prior art into two, or remove the incomplete part in the solar battery sheet 100 in the prior art to obtain a total of 72 half-cell sheets 200, divide The 72 half-solar cells are arranged in 4 columns × 18 rows = 72 pieces according to the method shown in Figure 4, and 18 half-cells 200 in each column are connected in series to form a small series, and then two adjacent small series are connected in parallel to form a middle series, and then Two adjacent medium strings are connected in series to form a large string to form a half-cell photovoltaic module. Using the same batch of 36 prior art solar cells 100 connected in series to form a photovoltaic module, compare the electrical performance of the photovoltaic module assembled with half cells, the relevant technical parameters are shown in the table below, from which it can be seen that the two The open-circuit voltage and short-circuit current are basically the same, however, the maximum power of the half-cell module is about 3.4% higher than that of the conventional module.

Optionally, the 72 half-cells 200 can also be connected in series with 36 half-cells 200 in the left half as the left battery string, and the 36 half-cells in the right half can be connected in series as the right string as shown in Figure 5 battery string, and then connect the left battery string and the right battery string in parallel to form a half-solar cell photovoltaic module.

Optionally, the 72 half-cells can also be connected in series with 36 half-cells 200 in the upper half as the upper battery string, and the 36 half-cells in the lower half can be connected in series as the lower battery string as shown in FIG. The upper battery string and the lower battery string are connected in parallel to form a half-solar cell photovoltaic module.

Example 2

Referring to Fig. 7, select the prior art interdigitated back-contact solar cells 100 of the same specification batch with a size of 125mm×125mm, randomly select 50 pieces of them, and connect them in series according to the arrangement of 5 columns×10 rows=50 pieces Form the photovoltaic module of prior art; With reference to Fig. 8, take the same batch of solar cells 100 and divide into two or remove the incomplete parts in the prior art solar cells 100 to obtain a total of 100 half-cells 200, the The 100 half-solar cells are arranged as 10 columns × 10 rows = 100 pieces according to the method shown in Fig. Two adjacent medium strings are connected in series to form a large string, thus forming a half-cell photovoltaic module. Comparing the electrical performance of photovoltaic modules and half-cell photovoltaic modules in the prior art, the detection parameters are shown in the table below, from which it can be seen that the open circuit voltage and short-circuit current of the two are basically the same, but half-solar cell The maximum power of the module is about 4.8% higher than that of conventional modules.

Example 3

Referring to Fig. 9, select polycrystalline solar cells 100 of the same batch in the prior art with a size of 156mm×156mm, randomly select 60 pieces of them, and connect them in series according to the arrangement of 6 columns×10 rows=60 pieces to form a diagram The prior art solar cell photovoltaic assembly shown in 9; with reference to Fig. 10, the solar cell sheet of the prior art is divided into two in the middle, or the incomplete part in the solar cell sheet 100 of the prior art is removed to obtain the solar cell photovoltaic assembly shown in Fig. 2 120 half-cells 200, arrange these 120 half-cells 200 into 6 columns × 20 rows = 120 pieces according to the method shown in Fig. Three small strings are connected in parallel to form a medium string, and then three adjacent medium strings are connected in series to form a large string, thereby forming a half-cell photovoltaic module.

Optionally, 120 half-cells can also be connected in series with 60 half-cells 200 in the left half as the left battery string, and 60 half-cells 200 in the right half can be connected in series as the right battery as shown in Figure 11 string, and then connect the left battery string and the right battery string in parallel to form a half-cell photovoltaic module.

Optionally, the 120 half-cells can also be connected in series as shown in Figure 12. The 60 half-cells in the upper half are connected in series as the upper battery string, and the 60 half-cells in the lower half are connected in series as the lower battery string, and then the upper battery The string and the lower battery string are then connected in parallel to form a half-cell photovoltaic module. Comparing the electrical properties of existing photovoltaic modules and half-cell photovoltaic modules, the parameters are shown in the table below after testing. It can be seen from the table that the open circuit voltage and short-circuit current of the two are basically the same, but the maximum power of the half-cell module About 5.2% higher than conventional components.

It can be seen from the above-mentioned embodiments that half-cells with a half-size of the cell size of 125mm×125mm or 156mm×156mm in the prior art can be used to make full use of a part of the discarded cells in the prior art and become waste. Weibao, by regularly combining several half-cells in series and parallel according to the positive and negative directions, and finally packaging them together to form the half-cell photovoltaic module, can effectively reduce the self-power loss caused by the internal resistance of the photovoltaic module , so as to improve the power output of photovoltaic modules. Compared with the combination of existing cells, the maximum power can be increased by 3%-6% when the open circuit voltage and short circuit current are basically unchanged. A higher photoelectric conversion rate is achieved.

After describing the implementation of the present invention in detail, those skilled in the art can clearly understand that various changes and modifications can be made without departing from the scope and spirit of the above-mentioned patent application. Any modifications, equivalent changes and modifications all belong to the scope of the technical solutions of the present invention, and the present invention is not limited to the implementations of the examples in the specification.

Claims (3)

1. A method for manufacturing a half-cell photovoltaic module, comprising arranging a substrate of a solar cell, characterized in that: a half-cell photovoltaic module comprises the following manufacturing steps: A． The size of the solar cell is processed into 125mm×62.5mm or 156mm×78mm respectively, and the electrodes are welded to form a half cell; B． Connect the half-cells on the substrate according to any of the following connection methods: B1. Half of the half-cells in the entire solar cell module are connected in series in rows/columns, and the other half are connected in parallel in rows/columns, including the upper and lower halves divided along the transverse midline and along the longitudinal direction. The left and right half-cells divided by the midline, the number of the upper and lower halves or the left and right half-cells is equal; B2. In the entire solar cell module, after each column/row is connected in series, two adjacent columns/rows are connected in parallel to form a middle string, and the parallel connected middle string is connected in series with other middle strings again to form a large string; C． In order to achieve the connection methods in B1 and B2, the matrix arrangement of the half-cells is divided into the following types, and one of the connection methods in the above step B can be realized according to any one of the matrix arrangements: C1. The electrode directions of odd-numbered columns/rows and even-numbered columns/rows of the half-cell sheets are opposite; C2. The center line of the width of the previous substrate is the axis of symmetry and the module is divided into two parts, the left and the right, and the electrodes of the odd and even columns of the half-cells in each part have opposite directions; C3. The center line of the length of the previous substrate is the axis of symmetry to divide the assembly into upper and lower parts, and the electrodes of the odd and even columns of the half-cells in each part have opposite directions; C4. The center line of the width of the previous substrate is the axis of symmetry and the module is divided into two symmetrical parts. The electrodes of the two outermost columns of each part have the same direction. If there is a third column, the electrode direction of the third column is opposite. 2. The manufacturing method of a half-cell photovoltaic module according to claim 1, characterized in that: the number of arrangement of the half-cells in the module is X column × Y row = N pieces, where X is a matrix column Y is the number of matrix rows and both X and Y are positive integers, and satisfy 8≤X≤16, 12≤Y≤24, X≤Y. 3. The manufacturing method of a half-cell photovoltaic module according to claim 1, wherein the half-cell comprises monocrystalline silicon solar cells, polycrystalline silicon solar cells, crystalline silicon heterojunction solar cells, interdigitated Back contact cell, emitter perforated wound cell.