Solar photovoltaic module

Abstract

The application relates to the technical field of solar photovoltaic modules, in particular to a solar photovoltaic module. The solar photovoltaic module comprises a body, a diode chip arranged in the body, and a first conductive metal sheet and a second conductive metal sheet respectively welded to the positive electrode and the negative electrode of the diode chip and connected with bus bars in the body. The technical problem of high cost and complicated process of the existing wiring box is solved.

Description

Technical Field

[0001] This application relates to the field of solar photovoltaic module technology, and more particularly to a solar photovoltaic module. Background Technology

[0002] As a power generation device, solar photovoltaic modules contain transmission circuits. In order to transmit electrical energy, photovoltaic junction boxes are usually installed. The main function of the junction box is to connect the internal solar cell circuit of the module to the external circuit through the positive and negative cables of the junction box. It is equipped with bypass diodes to protect the battery string.

[0003] Furthermore, the junction boxes commonly used in the industry are usually integrated or split-type, with the three-part junction box being the most widely used among the split-type. However, the three-part junction box requires the cost of three box bodies and three potting compounds. At the same time, the three openings in the back glass also increase the cost. In addition, the installation of the junction box body requires three times, which increases the process cycle and makes the process cumbersome. This runs counter to the current trend of cost reduction in photovoltaic modules. Utility Model Content

[0004] The purpose of this application is to provide a solar photovoltaic module to solve the technical problems of high cost and complicated process of the existing junction box method.

[0005] This application provides a solar photovoltaic module, comprising: ontology, and A diode chip is built into the body, and the positive and negative terminals of the diode chip are respectively welded with a first conductive metal sheet and a second conductive metal sheet, which are respectively connected to the busbar inside the body.

[0006] Furthermore, the positive and negative terminals of the diode chip are connected to the positive and negative terminals of the central busbar through the first conductive metal sheet and the second conductive metal sheet, respectively.

[0007] Furthermore, the solar photovoltaic module also includes a first welding lead and a second welding lead, wherein the two ends of the first welding lead are respectively welded to the positive electrode of the first conductive metal sheet and the central busbar, and the two ends of the second welding lead are respectively welded to the negative electrode of the second conductive metal sheet and the central busbar.

[0008] Furthermore, the diode chip has a flat structure, with the positive and negative terminals located on the upper and lower surfaces of the diode chip, respectively.

[0009] Furthermore, the first welding lead includes a first straight segment, a bent connecting segment, and a second straight segment connected in sequence. The other end of the first straight segment is welded to the first conductive metal sheet, and the other end of the second straight segment is welded to the positive electrode of the central busbar. The second welding lead is straight, with its upper surface at one end welded to the second conductive metal sheet, and its lower surface at the other end welded to the negative electrode of the central busbar.

[0010] Furthermore, the photovoltaic backplane of the main body has a positive electrode opening and a negative electrode opening, which are electrically connected to the diode chip through the busbar.

[0011] Furthermore, the busbar includes a central busbar and an edge busbar, the edge busbar extending to the central busbar; The positive and negative openings are located near the edge of the photovoltaic backsheet and are connected to the edge busbar.

[0012] Furthermore, the temperature at the location of the diode chip is lower than the temperature at the locations of the positive electrode opening and the negative electrode opening.

[0013] Furthermore, the diode chip is embedded in the middle of the body, and the positive and negative openings are located at the edge of the photovoltaic backsheet.

[0014] Furthermore, at least one layer of protective adhesive film is laid between the photovoltaic backsheet and the diode chip.

[0015] Compared with the prior art, the solar photovoltaic module provided in this application has a built-in diode chip directly embedded inside its body, and a first conductive metal sheet and a second conductive metal sheet are welded to the positive and negative terminals of the diode chip, respectively, so as to connect to the busbar inside the solar photovoltaic module to connect the circuit.

[0016] Since the essential function of the existing intermediate junction box is equivalent to a bypass diode, which protects the circuit during the operation of the solar photovoltaic module and will not be activated when there is no abnormality in the circuit, and the core component of the intermediate junction box is the internal diode chip, this application directly eliminates the use of the intermediate junction box and directly installs an internal diode chip. After eliminating the external box structure, conductive metal sheets are directly soldered to the positive and negative terminals of the diode chip to connect the circuit, thereby completely replacing the function of the original intermediate junction box.

[0017] Furthermore, reducing one intermediate junction box reduces the cost per box, the cost of applying glue to the bottom of the box, the cost of opening a back glass panel, and the cost of installing the junction box. This increases production capacity, reduces back shading of double-glass modules, and improves the bifaciality rate. It effectively reduces costs, increases production capacity, and shortens the process cycle, greatly alleviating the pressure to reduce costs. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the back structure of a solar photovoltaic module provided in an embodiment of this application; Figure 2 This is a top view of the solar photovoltaic module provided in the embodiments of this application; Figure 3 This is a schematic diagram of the diode chip connection circuit provided in an embodiment of this application.

[0020] Figure label: 100 - Solar photovoltaic modules; 10-Diode chip; 21 - First welding lead; 211 - First straight segment; 212-Bent connection section; 213 - Second straight segment; 22 - Second welding lead; 30-Central busbar; 31-Positive electrode central busbar; 32-Center busbar in the middle of the negative electrode; 40-Edge busbar; 50-cell battery; 60- Photovoltaic backsheet; 61 - Positive electrode opening; 62-Negative electrode opening; 201 - Positive electrode component; 202-Negative electrode component. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0026] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0027] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0028] like Figures 1 to 3 As shown, this application embodiment provides a solar photovoltaic module 100, including: a body, which is the body of the solar photovoltaic module 100, and a diode chip 10 built into the body. The positive and negative electrodes of the diode chip 10 are respectively welded with a first conductive metal sheet and a second conductive metal sheet (not shown in the figure). The first conductive metal sheet and the second conductive metal sheet are respectively connected to the busbar inside the body.

[0029] Compared with the prior art, the solar photovoltaic module 100 provided in this application embodiment has a built-in diode chip 10 directly installed inside its body, and a first conductive metal sheet and a second conductive metal sheet are respectively welded to the positive and negative terminals of the diode chip 10 to connect to the busbar inside the solar photovoltaic module 100 to connect the circuit, thereby replacing the function of the junction box used in the prior art, thereby achieving the purpose of reducing costs, increasing efficiency, and shortening the cycle time.

[0030] Since the essential function of the existing intermediate junction box is equivalent to a bypass diode, which plays a role in protecting the circuit when the solar photovoltaic module 100 is running and will not be activated when there is no abnormality in the circuit, and the core component of the intermediate junction box is the internal diode chip 10, this application directly eliminates the use of the intermediate junction box and directly installs an internal diode chip 10. After eliminating the external box structure, conductive metal sheets are directly soldered to the positive and negative terminals of the diode chip 10 to connect the circuit, thereby completely replacing the function of the original intermediate junction box.

[0031] Furthermore, reducing one intermediate junction box reduces the cost per box, the cost of applying glue to the bottom of the box, the cost of opening a back glass panel, and the cost of installing the junction box. This increases production capacity, reduces back shading of double-glass modules, and improves the bifaciality rate. It effectively reduces costs, increases production capacity, and shortens the process cycle, greatly alleviating the pressure to reduce costs.

[0032] In a preferred embodiment, the positive and negative terminals of the aforementioned diode chip 10 are connected to the central busbar 30. Specifically, the positive and negative terminals of the diode chip 10 are respectively connected to the positive terminal of the central busbar 30 (i.e., ...) through its aforementioned first and second conductive metal sheets. Figure 3 The positive terminal (middle busbar 31) and the negative terminal (i.e., the middle busbar 30 shown) are shown. Figure 3 The negative electrode middle busbar 32 shown is connected to it.

[0033] Since the central busbar 30 serves as the main channel for current collection within the solar photovoltaic module 100, and is arranged along the centerline of the cell string, it is responsible for concentrating and discharging the current generated by multiple cells 50 connected in series, thus playing a core role in current collection. Therefore, connecting the diode chip 10 to the central busbar 30 can provide more significant circuit protection and also more effectively replace the intermediate junction box.

[0034] In a further embodiment, the aforementioned diode chip 10 can also be welded to the central busbar 30 by means of welding leads. The welding leads are generally made of high-purity oxygen-free copper substrate, and the contact resistance can be controlled below 0.5mΩ. Compared with the traditional bolt connection, the series resistance can be reduced and the energy conversion efficiency of the component can be significantly improved.

[0035] Specifically, such as Figure 3 As shown, the diode chip 10 can include a first welding lead 21 and a second welding lead 22. One end of the first welding lead 21 is welded to the first conductive metal sheet of the positive electrode of the diode chip 10, and the other end is welded to the positive electrode (i.e., the positive electrode middle busbar 31) of the middle busbar 30, which is connected to both ends of the first lead 21. One end of the second welding lead 22 is welded to the second conductive metal sheet of the negative electrode of the diode chip 10, and the other end is welded to the negative electrode (i.e., the negative electrode middle busbar 32) of the middle busbar 30. This allows the first conductive metal sheet to be welded to the positive electrode of the middle busbar 30 via the first welding lead 21, and the second conductive metal sheet to be welded to the negative electrode of the middle busbar 30 via the second welding lead 22. This not only facilitates connection but also ensures welding reliability and reduces series resistance.

[0036] Preferably, the aforementioned diode chip 10 has a flat structure, which is small in size and thin in thickness, and occupies a much smaller volume compared to existing junction boxes.

[0037] In a more specific embodiment, the positive and negative terminals of the diode chip 10 are located on the upper and lower end faces of the diode chip 10, respectively.

[0038] like Figure 3 As shown, the first welding lead 21 may specifically include a first straight segment 211, a bent connecting segment 212, and a second straight segment 213 connected in sequence. The other end of the first straight segment 211 is welded to the aforementioned first conductive metal sheet, and the other end of the second straight segment 213 is welded to the positive electrode (i.e., the positive electrode central busbar 31) of the central busbar 30. This welding lead structure is more adaptable to spatial distribution, facilitates reasonable utilization and arrangement, and allows for a more compact connection.

[0039] The second welding lead 22 can be straight. The upper surface of one end of the second welding lead 22 is welded to the aforementioned second conductive metal sheet, and the lower surface of the other end of the second welding lead 22 is welded to the negative electrode of the central busbar 30 (i.e., the negative electrode central busbar 32). This welding lead structure has the shortest connection distance and the fastest transmission speed.

[0040] Another preferred embodiment is, as Figure 1 As shown, the solar photovoltaic module 100 is externally encapsulated with a photovoltaic backsheet 60. This backsheet 60 has only two openings: a positive electrode opening 61 and a negative electrode opening 62, for connecting to the positive electrode module 201 and the negative electrode module 202. By eliminating the back glass opening at the intermediate junction box location and providing only two openings (positive electrode opening 61 and negative electrode opening 62), the price of glass can be reduced by approximately one yuan per piece, further lowering the glass procurement cost and overall cost.

[0041] The positive electrode opening 61 and the negative electrode opening 62 are electrically connected to the diode chip 10 via a busbar. The busbar includes a central busbar 30 and an edge busbar 40, with the edge busbar 40 extending to the central busbar 30. The positive electrode opening 61 and the negative electrode opening 62 are located near the edge of the photovoltaic backsheet 60, therefore, it is preferable that the positive electrode opening 61 and the negative electrode opening 62 are connected to the edge busbar 40, so that current is directly output from the edge busbar, reducing intermediate connection nodes.

[0042] In one optional embodiment, at least one layer of protective film is laid between the photovoltaic backsheet 60 and the diode chip 10. Generally, one layer of film and two layers of film are laid. The diode chip 10 is small in size and thin in thickness. Under the protection of the one layer of film and the two layers of film, it can be better embedded inside the module glass. At the same time, it avoids contact with external moisture, and has better sealing and anti-aging properties.

[0043] Based on the solar photovoltaic module 100 provided in the above embodiments of this application, several tests are performed on it to examine its working performance.

[0044] The first test involved diode chip resistance testing. Diode chips with different thicknesses (such as 0.952mm, 0.961mm, and 0.957mm) were tested for resistance, and the results are shown in Table 1 below.

[0045] Table 1:

[0046] As can be seen from Table 1, the on-resistance of diode chips of three commonly used thicknesses is within a stable and normal range, indicating that their performance is normal and there are no problems such as aging.

[0047] The second test, the reverse current loading (RCO) test, involves applying two different currents: 1.35 times the current of 30 amps and 1.35 times the current of 35 amps. The diode chip 10 is installed in the middle of the solar photovoltaic module 100, and the positive electrode opening 61 and the negative electrode opening 62 are located at the edge of the photovoltaic backsheet 60. The results are shown in Table 2 below.

[0048] Table 2:

[0049] As shown in Table 2, the highest temperature in the middle quadrant is lower than that in the positive and negative quadrants. Since the diode chip 10 is located in the middle of the solar photovoltaic module 100, the temperature at the location of the diode chip 10 is lower than the temperatures at the locations of the positive and negative openings 61 and 62. Furthermore, eliminating the middle junction box results in a lower temperature at the same location compared to the positive and negative electrode positions, making the solar photovoltaic module 100 safer.

[0050] The third test, the EL test after module lamination, found that after removing the intermediate junction box, in the same position, after the diode chip was built in, the corresponding position of the cell had no hidden cracks or abnormal breakage after module lamination.

[0051] The fourth test is the module bifaciality test. A comparison is made between the solar photovoltaic modules before the junction box was removed and those after the junction box was removed and with built-in diode chips. The results are shown in Table 3 below.

[0052] Table 3:

[0053] Where Voc represents open-circuit voltage, Isc represents short-circuit current, Pmax represents maximum power, Vpmax represents the voltage level of maximum power, Ipmax represents the current level of maximum power, Rs represents series resistance, Rsh represents parallel resistance, and FF represents fill factor.

[0054] As shown in Table 3, the hyperbola of the solar photovoltaic module 100 with the intermediate junction box removed and the built-in diode chip in this application increased by 1.58% compared with the solar photovoltaic module before the intermediate junction box was removed, which confirms the aforementioned conclusion that reducing the back shading of the double-glass module improves the upper hyperbola.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A solar photovoltaic module, characterized in that, include: ontology, and A diode chip is built into the body, and the positive and negative terminals of the diode chip are respectively welded with a first conductive metal sheet and a second conductive metal sheet, which are respectively connected to the busbar inside the body.

2. The solar photovoltaic module according to claim 1, characterized in that, The positive and negative terminals of the diode chip are connected to the positive and negative terminals of the central busbar through the first conductive metal sheet and the second conductive metal sheet, respectively.

3. The solar photovoltaic module according to claim 2, characterized in that, It also includes a first welding lead and a second welding lead, wherein the two ends of the first welding lead are respectively welded to the positive electrode of the first conductive metal sheet and the middle busbar, and the two ends of the second welding lead are respectively welded to the negative electrode of the second conductive metal sheet and the middle busbar.

4. The solar photovoltaic module according to claim 3, characterized in that, The diode chip has a flat structure, with the positive and negative terminals located on the upper and lower surfaces of the diode chip, respectively.

5. The solar photovoltaic module according to claim 4, characterized in that, The first welding lead includes a first straight segment, a bent connecting segment and a second straight segment connected in sequence. The other end of the first straight segment is welded to the first conductive metal sheet, and the other end of the second straight segment is welded to the positive electrode of the central busbar. The second welding lead is straight, with its upper surface at one end welded to the second conductive metal sheet, and its lower surface at the other end welded to the negative electrode of the central busbar.

6. The solar photovoltaic module according to any one of claims 1 to 5, characterized in that, The photovoltaic backplane of the main body has a positive electrode opening and a negative electrode opening, and the positive electrode opening and the negative electrode opening are electrically connected to the diode chip through the bus bar.

7. The solar photovoltaic module according to claim 6, characterized in that, The busbar includes a central busbar and an edge busbar, the edge busbar extending to the central busbar; The positive and negative openings are located near the edge of the photovoltaic backsheet and are connected to the edge busbar.

8. The solar photovoltaic module according to claim 7, characterized in that, The temperature at the location of the diode chip is lower than the temperature at the locations of the positive electrode opening and the negative electrode opening.

9. The solar photovoltaic module according to claim 8, characterized in that, The diode chip is built into the middle of the body, and the positive and negative openings are located at the edge of the photovoltaic backsheet.

10. The solar photovoltaic module according to claim 6, characterized in that, At least one protective film is also laid between the photovoltaic backsheet and the diode chip.

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