Junction box and photovoltaic module

Abstract

The utility model relates to the technical field of solar cells, and provides a junction box and a photovoltaic module, the junction box comprises a junction box main body and a hydrochromic layer, the junction box main body is provided with a cavity, and at least part of the wall body of the junction box main body is a transparent wall body; the hydrochromic layer is arranged on the side, close to the cavity, of the transparent wall body, and the hydrochromic layer can change color after making contact with water. According to the junction box, the transparent wall body and the hydrochromic layer are arranged on the junction box, in the using process, whether water vapor enters the junction box or not can be judged through the color change of hydrochromism, and the reliability of the junction box is improved.

Description

Technical Field

[0001] This utility model relates to the field of solar cell technology, and in particular to a junction box and a photovoltaic module. Background Technology

[0002] Junction boxes are a crucial component of photovoltaic (PV) modules. During operation, they connect to the internal busbars of the PV module, primarily serving as electrical connections and protecting the circuit. If moisture enters the junction box during PV module operation, it not only poses a risk of electrical leakage but may also cause chemical corrosion of the internal metal components, leading to junction box failure or even burnout. Although traditional technologies employ sealing rings and sealants to improve the junction box's sealing performance, over extended use, it becomes impossible to determine whether moisture has entered the junction box, thus compromising its reliability. Utility Model Content

[0003] Based on this, this application provides a junction box and a photovoltaic module capable of determining whether water vapor has entered.

[0004] In a first aspect, this application provides a junction box, the junction box comprising:

[0005] A junction box body having a cavity, and at least a portion of the wall of the junction box body being a transparent wall.

[0006] A water-sensitive color-changing layer is disposed on the side of the transparent wall near the cavity, and the water-sensitive color-changing layer can change color upon contact with water.

[0007] In some embodiments, a water-absorbing layer is also provided inside the junction box body, which is used to absorb water entering the cavity.

[0008] In some embodiments, the junction box body includes a box body and a cover body that overlap each other, and the cavity formed between the box body and the cover body is the cavity.

[0009] The box body includes a base and side walls, the side walls being disposed on the base, and at least a portion of the side walls forming the transparent wall.

[0010] In some embodiments, the transparent wall and the sidewall are separate structures.

[0011] In some embodiments, the cover has a movable pressing block and a plurality of locking blocks on one side surface near the cavity; the locking blocks are used to engage and position the absorbent layer; the movable pressing block is used to rotate and press the absorbent layer, and cooperates with the locking blocks to fix the absorbent layer.

[0012] In some embodiments, a glue-applying groove is provided on the side surface of the base away from the sidewall along the circumference of the base.

[0013] In some embodiments, the cavity is also filled with sealant, and the base is provided with at least one sealant leakage hole.

[0014] In some embodiments, the base is further provided with feet on the side surface away from the sidewall.

[0015] In some embodiments, the junction box is further provided with a diode element, which includes a diode, at least two diode leads, and at least two terminals.

[0016] The diode is disposed within the cavity of the junction box, and two terminals are respectively disposed on both sides of the diode. The diode and the terminals are connected by the diode pins.

[0017] In some embodiments, the base has at least two busbar through holes, wherein the two busbar through holes are respectively opened at the positions of the terminal blocks.

[0018] In some embodiments, the water-chromic layer is disposed near the diode.

[0019] Secondly, this application provides a photovoltaic module, which includes a junction box as described in the first aspect, and a plurality of battery strings, wherein the busbars in the battery strings are all connected to the junction box.

[0020] Compared with traditional technologies, this application has at least the following beneficial effects:

[0021] This application sets part of the junction box wall as a transparent wall and sets a water-chromic layer in the transparent wall position. When water vapor enters the junction box, the water-chromic layer comes into contact with the water vapor and changes color, which can promptly detect whether there is a risk of water vapor entering the junction box, thereby reminding the operator to deal with the junction box, preventing water vapor from further corroding the components inside the junction box, and improving the reliability of the junction box. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the box body structure of a junction box provided in one embodiment of the present utility model;

[0023] Figure 2 This is a side view of the junction box body portion provided in one embodiment of the present utility model;

[0024] Figure 3 This is a schematic diagram of the bottom surface structure of a junction box base provided in one embodiment of the present utility model;

[0025] Figure 4 This is a schematic diagram of the water-absorbing layer on the cover of a junction box in one embodiment of the present invention.

[0026] Figure 5 This is a structural schematic diagram of the water-absorbing layer on the cover of a junction box in a disassembled state according to one embodiment of the present invention.

[0027] Figure 6 This is a partial enlarged view of the locking block on the cover of a junction box provided in one embodiment of the present utility model.

[0028] Among them, 100-junction box body; 110-transparent wall; 120-box body; 121-base; 122-side wall; 123-busbar perforation; 124-glue groove; 125-glue leakage hole; 126-foot pad; 127-auxiliary hole; 130-cover; 131-movable pressure block; 132-clamping block; 133-rotating shaft; 134-pressure block; 200-water-chromic layer; 300-water-absorbing layer; 400-diode element; 410-diode; 420-diode pin; 430-junction socket; 431-metal bracket; 432-positioning post; 433-solder block; 434-output wire. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings, embodiments, and examples. These embodiments and examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The purpose of providing these embodiments and examples is to enable a more thorough and comprehensive understanding of the disclosure of the present invention. It should also be understood that the present invention can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present invention, and the equivalent forms obtained also fall within the protection scope of the present invention. Furthermore, numerous specific details are set forth in the following description to provide a fuller understanding of the present invention. It should be understood that the present invention can be implemented without one or more of these details.

[0030] It should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0031] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," "fixed," and "set" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the meaning of the above terms in this utility model according to the specific circumstances.

[0032] In this utility model, "optionally", "optionally", and "optional" mean that they are optional, that is, they are selected from either "with" or "without". If there are multiple "options" in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "option" is independent.

[0033] In this utility model, the technical features described in an open-ended manner include both closed technical solutions composed of the listed features and open technical solutions that include the listed features.

[0034] In this utility model, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0035] All documents mentioned in this utility model are incorporated herein by reference as if each document were individually incorporated by reference. Unless they conflict with the utility model's purpose and / or technical solution, all cited documents are incorporated herein by reference in their entirety and for all purposes. When citing documents in this utility model, the definitions of relevant technical features, terms, nouns, phrases, etc., are also incorporated herein by reference. Examples and preferred embodiments of the cited technical features may also be incorporated herein by reference, but only to the extent that they enable the implementation of this utility model. It should be understood that when the cited content conflicts with the description in this utility model, this utility model shall prevail or be adapted to the description in this utility model.

[0036] In traditional photovoltaic (PV) modules, junction boxes utilize sealing rings or sealants to improve their sealing performance. Sealing rings are placed between the junction box body and cover to enhance the seal and prevent moisture from entering. Sealants completely fill the junction box with sealant, effectively preventing moisture from corroding the internal metal components. While both methods offer some waterproofing, as PV modules age, the sealing rings and sealants can deteriorate, leaving a risk of moisture ingress. If moisture enters, operators may not detect it, leading to junction box failure or burnout, resulting in poor reliability.

[0037] Based on this, the first aspect of this application provides a junction box, such as Figure 1 and Figure 2 As shown, the junction box includes a junction box body 100 and a water-chromic layer 200.

[0038] The junction box body 100 has a cavity, and at least a portion of the wall of the junction box body 100 is a transparent wall 110. A water-chromic layer 200 is disposed on the side of the transparent wall 110 near the cavity, and the water-chromic layer 200 can change color upon contact with water.

[0039] This application sets part of the junction box wall as a transparent wall 110, and sets a water-chromic layer 200 at the position of the transparent wall 110. When water vapor enters the junction box, the water-chromic layer 200 comes into contact with the water vapor and changes color, which can promptly detect whether there is a risk of water vapor entering the junction box, thereby reminding the operator to handle the junction box, preventing water vapor from further corroding the components inside the junction box, and improving the reliability of the junction box.

[0040] It is understood that the transparent wall 110 in this application is sufficient to allow the color change of the water-chromic layer 200 inside the junction box to be observed. It can be made of transparent materials, such as transparent wall made of polycarbonate (PC) or transparent wall made of transparent ceramic materials.

[0041] It is understood that the water-chromic layer 200 in this application refers to a material layer that changes color upon contact with water vapor. It can be supported by a material that changes color upon contact with water, such as a water-chromic layer of a blue colorant or a water-chromic layer of polyacetylene. Specifically, the blue colorant changes from blue to red upon contact with water vapor; the polyacetylene changes from blue to red upon contact with water vapor.

[0042] It should be noted that this application does not impose specific requirements or limitations on the electrical components installed in the junction box, and the appropriate components can be selected based on the specific application scenario of the junction box. For example, diode components can be installed in the junction box, and these diode components can be axial diode components or modular diode components, etc.

[0043] It is understood that the shape of the junction box in this application can be reasonably selected according to the application requirements, such as being rectangular or circular.

[0044] In some embodiments, the water-chromic layer 200 can be detachably disposed on the junction box body 100, so that after the water-chromic layer 200 changes color, it can be removed and replaced with a new water-chromic layer 200, and the junction box can be resealed to achieve sealing treatment of the junction box without replacing the entire junction box.

[0045] In some embodiments, as Figure 4 and Figure 5 As shown, a water-absorbing layer 300 is also provided inside the junction box body 100. The water-absorbing layer 300 is used to absorb water entering the cavity. This application provides a water-absorbing layer 300 inside the junction box body 100 to absorb moisture entering the cavity, effectively preventing moisture from corroding the components inside the junction box body 100. The water-absorbing layer 300 can be replaced periodically, thereby improving the reliability and waterproof performance of the junction box.

[0046] It is understood that the absorbent layer 300 in this application only needs to be sufficient to absorb moisture. For example, it can be made of a desiccant (such as anhydrous calcium chloride).

[0047] In some embodiments, as Figure 1 and Figure 4 As shown, the junction box body 100 includes a box body 120 and a cover body 130 that overlap each other, and the cavity formed between the box body 120 and the cover body 130 is a cavity. Optionally, a sealing ring is provided at the connection between the box body 120 and the cover body 130.

[0048] For example Figure 1 As shown, the box 120 includes a base 121 and a side wall 122. The side wall 122 is disposed on the base 121, and at least a portion of the side wall 122 in the box 120 forms a transparent wall 110.

[0049] It is understood that the transparent wall 110 can be an integral structure with the side wall 122 or a separate structure. In some embodiments, the transparent wall 110 and the side wall 122 are separate structures. For example, the transparent wall 110 and the side wall 122 are connected by a snap-fit ​​method, a glue-sealing method, or a fully embedded method, which ensures both the sealing of the side wall 122 and the visibility of the transparent wall 110.

[0050] In some embodiments, as Figure 4 and Figure 5 As shown, the cover 130 has a movable pressing block 131 and multiple locking blocks 132 on one side surface near the cavity; as Figure 6 As shown, the locking block 132 is used to engage and position the absorbent layer 300; the movable pressing block 131 is used to rotate and press the absorbent layer 300, and cooperates with the locking block 132 to fix the absorbent layer 300. This application uses the movable pressing block 131 and multiple locking blocks 132 to detachably install the absorbent layer 300 onto the cover 130. When a color change is observed in the water-induced discoloration layer 200, indicating that moisture has entered the junction box and the absorbent layer 300 has completely absorbed water, the absorbent layer 300 can be removed and replaced when processing the junction box, and the junction box can be resealed. This avoids completely replacing the junction box, improving processing efficiency and waterproofing effect.

[0051] Optionally, such as Figure 4 and Figure 5 As shown, the movable pressing block 131 includes a rotating shaft 133 and a pressing block 134 disposed on the cover 130, and the pressing block 134 rotates around the rotating shaft 133.

[0052] In some embodiments, as Figure 3 As shown, a glue-applying groove 124 is provided on the side surface of the base 121 away from the side wall 122 along the circumference of the base 121. The glue-applying groove 124 provided in this application can provide a glue-applying path for applying sealant.

[0053] In some embodiments, the cavity is also filled with sealant, for example... Figure 3 As shown, at least one glue leakage hole 125 is also provided on the base 121. The glue leakage hole 125 provided in this application can ensure that the potting compound adheres tightly to the back of the component during the glue pouring process of the junction box.

[0054] In some embodiments, such as Figure 3 As shown, a plurality of feet 126 are also provided on the side surface of the base 121 away from the side wall 122. The feet 126 provided on the base 121 in this application can ensure that there is sufficient sealant filling between the base 121 and the back of the photovoltaic module.

[0055] It is understandable that a junction box can be a positive terminal junction box, a negative terminal junction box, or an intermediate terminal junction box. The components and wiring within the junction box can be adjusted according to the structure of different types of junction boxes. Different type markings can be set on different types of junction boxes for differentiation.

[0056] In some embodiments, such as Figure 1As shown, the junction box also contains a diode element 400, which is an axial diode element, including a diode 410, at least two diode pins 420 and at least two terminal blocks 430.

[0057] The diode 410 is disposed inside the cavity of the junction box, and two terminals 430 are respectively disposed on both sides of the diode 410. The diode 410 and the terminals 430 are connected by diode pins 420.

[0058] Alternatively, for example Figure 1 As shown, the terminal block 430 includes a metal bracket 431 and a solder block 433. A positioning post 432 is provided inside the housing 120. The metal bracket 431 is mounted on the positioning post 432, and the solder block 433 is mounted on the metal bracket 431. The metal bracket 431 is used to fix the diode 410, and the solder block 433 is used to connect the busbar and the metal bracket 431. The metal bracket 431 can also be connected to the output wire 434.

[0059] In some embodiments, as Figure 1 and Figure 3 As shown, the base 121 has at least two busbar through holes 123, which are respectively located at the positions of the terminal block 430. Optionally, the base 121 also has an auxiliary hole 127, which is located next to the busbar through hole 123 and is used to assist the busbar in passing through the busbar through hole 123.

[0060] In some embodiments, such as Figure 1 As shown, the water-chromic layer 200 is disposed near the diode 410. By disposing the water-chromic layer 200 near the diode 410, this application can detect water vapor near the diode 410, thereby effectively ensuring that the diode 410 is not corroded by water vapor.

[0061] The second aspect of this application provides a photovoltaic module, which includes a junction box as described in the first aspect, and a plurality of battery strings, wherein the busbars in the battery strings are all connected to the junction box.

[0062] In some embodiments, the battery string includes multiple battery cells connected by busbars to form the battery string.

[0063] In some embodiments, the solar cell may be at least one of HJT solar cells, TOPcon solar cells, PERC solar cells, or perovskite solar cells.

[0064] In some embodiments, the solar cell may also be a tandem solar cell, such as a perovskite / crystalline silicon tandem solar cell.

[0065] In some embodiments, the photovoltaic module further includes a backsheet, an encapsulation layer, and a panel layer. The encapsulation layer and the backsheet are stacked sequentially on the back side of the solar cell, and the panel layer is disposed on the front side of the solar cell. Optionally, the encapsulation layer and the backsheet are sequentially disposed on the back side of the solar cell in a direction away from the solar cell. It should be noted that, in this application, "back side" refers to the side that is not exposed to sunlight. Correspondingly, "front side" refers to the side that is directly exposed to sunlight.

[0066] In some embodiments, the photovoltaic module further includes a frame. A laminate formed by the panel layer, solar cells, encapsulation layer, and backsheet is disposed within the frame. The frame is used to improve the mechanical strength of the laminate.

[0067] In summary, this application sets part of the junction box wall as a transparent wall 110, and sets a water-chromic layer 200 at the location of the transparent wall 110. When water vapor enters the junction box, the water-chromic layer 200 comes into contact with the water vapor and changes color, which can promptly detect whether there is a risk of water vapor entering the junction box, thereby reminding the operator to handle the junction box, preventing water vapor from further corroding the components inside the junction box, and improving the reliability of the junction box.

[0068] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0069] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A junction box, characterized in that, The junction box includes: A junction box body (100) includes a box body (120) and a cover body (130) that fit together, and the cavity formed between the box body (120) and the cover body (130) is a cavity; the box body (120) includes a base (121) and a side wall (122), the side wall (122) is disposed on the base (121), and at least a portion of the side wall (122) in the box body (120) is a transparent wall (110); A water-sensitive color-changing layer (200) is disposed on the side of the transparent wall (110) near the cavity, and the water-sensitive color-changing layer (200) can change color after contact with water; A water-absorbing layer (300) is disposed inside the junction box body (100) and is used to absorb water entering the cavity. A movable pressing block (131) and a plurality of locking blocks (132) are provided on the side surface of the cover (130) near the cavity. The locking blocks (132) are used to engage and position the water-absorbing layer (300). The movable pressing block (131) is used to rotate and press the water-absorbing layer (300) and cooperate with the locking blocks (132) to fix the water-absorbing layer (300).

2. The junction box as described in claim 1, characterized in that, The transparent wall (110) and the side wall (122) are separate structures.

3. The junction box as described in claim 1, characterized in that, The base (121) has a glue-applying groove (124) on the side surface away from the side wall (122) along the circumference of the base (121); and / or, The cavity is also filled with sealant, and the base (121) is also provided with at least one sealant leakage hole (125); and / or, The base (121) is also provided with a foot (126) on the side surface away from the side wall (122).

4. The junction box as described in any one of claims 1-3, characterized in that, The junction box is also provided with a diode element (400), which includes a diode (410), at least two diode leads (420) and at least two terminal blocks (430); The diode (410) is disposed in the cavity of the junction box, and two terminals (430) are respectively disposed on both sides of the diode (410). The diode (410) and the terminals (430) are respectively connected by the diode pins (420).

5. The junction box as described in claim 4, characterized in that, The base (121) has at least two busbar through holes (123), wherein the two busbar through holes (123) are respectively opened at the positions of the terminal block (430).

6. The junction box as described in claim 4, characterized in that, The water-chromic layer (200) is disposed near the diode (410).

7. A photovoltaic module, characterized in that, The photovoltaic module includes a junction box as described in any one of claims 1-6, and a plurality of battery strings, wherein the busbars in the battery strings are all connected to the junction box.

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