Junction box and photovoltaic module

Abstract

The utility model relates to the technical field of photovoltaic cell manufacturing, in particular to a junction box and a photovoltaic assembly. The junction box is used for being electrically connected with a laminated battery and comprises a box body, and a first conductive metal sheet, a second conductive metal sheet and a third conductive metal sheet which are arranged in the box body, the first main circuit cable and the first auxiliary circuit cable are connected with the first conductive metal sheet, the second main circuit cable is connected with the second conductive metal sheet, and the second auxiliary circuit cable is connected with the third conductive metal sheet. Wherein the first conductive metal sheet is electrically connected with a first battery layer and a second battery layer in the laminated battery, and the second conductive metal sheet is electrically connected with one of the first battery layer and the second battery layer; and the third conductive metal sheet is electrically connected with the other one of the first battery layer and the second battery layer. The junction box can be adapted to the electric energy output of the laminated battery, the photoelectric conversion efficiency of the photovoltaic module is improved, and the cost is saved.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic cell manufacturing, in particular to a junction box and a photovoltaic component. Background Art

[0002] In the development history of photovoltaic cells, due to the existence of the SQ theoretical limit, the development space of conventional monocrystalline silicon cells is limited. At present, the photoelectric conversion efficiency of mainstream monocrystalline silicon cells on the market has reached 26.8%, close to its theoretical efficiency value of 29.4%. It is becoming increasingly difficult to further improve the photoelectric conversion efficiency of monocrystalline silicon cells.

[0003] According to the principle of spectrum matching, combining solar cells with different band gaps to form a tandem solar cell (also called a tandem cell) can greatly broaden the spectral response, reduce the loss of carriers, and thus greatly improve the photoelectric conversion efficiency of the cell. The main working principle of the tandem cell is: the wide band gap top cell absorbs high energy photons, and the narrow band gap bottom cell improves the photon utilization rate. The combination of the two can break through the theoretical efficiency limit of single crystal silicon cells.

[0004] However, the existing junction boxes of single crystal silicon cell photovoltaic modules cannot match the stacked cells. Therefore, it is urgent to design a junction box that can be adapted to the stacked cells to meet the power output of the stacked cells. Utility Model Content

[0005] The first purpose of the utility model is to provide a junction box that can be adapted to the power output of a laminated battery.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] The utility model provides a junction box, which is used to electrically connect to a laminated battery, and comprises:

[0008] A box body, wherein a first conductive metal sheet, a second conductive metal sheet and a third conductive metal sheet are arranged in the box body;

[0009] A first main circuit cable, one end of which passes through the box body and is connected to the first conductive metal sheet;

[0010] A first auxiliary circuit cable, one end of which passes through the box body and is connected to the first conductive metal sheet;

[0011] A second main circuit cable, one end of which passes through the box body and is connected to the second conductive metal sheet;

[0012] A second auxiliary circuit cable, one end of which passes through the box body and is connected to the third conductive metal sheet;

[0013] The first conductive metal sheet is electrically connected to both the first battery layer and the second battery layer in the stacked battery, the second conductive metal sheet is electrically connected to one of the first battery layer and the second battery layer to form a main circuit; the third conductive metal sheet is electrically connected to the other of the first battery layer and the second battery layer to form an auxiliary circuit.

[0014] As an optional technical solution for a junction box, the box body includes a box wall and a base, the box wall is arranged on the base around the edge of the base and encloses a mounting cavity, and the outer edge of the base protrudes from the outer side wall of the box wall.

[0015] As an optional technical solution for a junction box, an introduction hole is provided on the base, and the introduction hole is configured to allow a bus bar of the laminated battery to pass through.

[0016] As an optional technical solution of a junction box, the installation cavity includes an installation cavity, heat dissipation cavities are respectively provided on both sides of the installation cavity, and the first conductive metal sheet, the second conductive metal sheet and the third conductive metal sheet are arranged in the installation cavity.

[0017] As an optional technical solution of a junction box, a plurality of mounting grooves are provided in the mounting chamber, and the mounting grooves are configured to mount the first conductive metal sheet, the second conductive metal sheet, and the third conductive metal sheet.

[0018] As an optional technical solution for a junction box, at least one fixing column is provided in each installation slot, and fixing holes are provided on the first conductive metal sheet, the second conductive metal sheet and the third conductive metal sheet, and the fixing holes are adapted to be connected with the fixing columns.

[0019] As an optional technical solution for a junction box, a plurality of bosses are provided in the installation chamber, and the installation groove is formed between two adjacent bosses. The heights of the first conductive metal sheet, the second conductive metal sheet and the third conductive metal sheet are all lower than the height of the bosses, and the height of the box wall is higher than the height of the bosses.

[0020] As an optional technical solution of a junction box, the junction box further includes a bypass diode disposed in the installation chamber, one end of the bypass diode is connected to the first conductive metal sheet, and the other end of the bypass diode is connected to the second conductive metal sheet.

[0021] As an optional technical solution of a junction box, the junction box further comprises a box cover, and a buckle is provided on the box wall, and the buckle is snap-connected with the box cover.

[0022] The second purpose of the utility model is to provide a photovoltaic module, which has a higher photoelectric conversion efficiency and saves costs.

[0023] To achieve this purpose, the utility model adopts the following technical solutions:

[0024] The utility model provides a photovoltaic assembly, which comprises a laminated battery and the above-mentioned junction box, wherein the junction box is electrically connected to the laminated battery.

[0025] The beneficial effects of the utility model include at least:

[0026] The utility model provides a junction box, which is used to electrically connect with a stacked battery. The junction box includes a box body, a first conductive metal sheet, a second conductive metal sheet and a third conductive metal sheet arranged in the box body; a first main circuit cable and a first auxiliary circuit cable connected to the first conductive metal sheet, a second main circuit cable connected to the second conductive metal sheet, and a second auxiliary circuit cable connected to the third conductive metal sheet. Among them, the first conductive metal sheet is electrically connected to the first battery layer and the second battery layer in the stacked battery, the second conductive metal sheet is electrically connected to one of the first battery layer and the second battery layer; the third conductive metal sheet is electrically connected to the other of the first battery layer and the second battery layer, so as to improve the flexible adaptability of the junction box and save costs. The stacked battery in the utility model is a three-terminal structure perovskite stacked battery, that is, it has a common terminal connected to the first conductive metal sheet, a port connected to the second conductive metal sheet, and a port connected to the third conductive metal sheet. The first conductive metal sheet serves as the positive electrode of the main circuit and the common positive electrode of the auxiliary circuit, the second conductive metal sheet serves as one of the negative electrode of the main circuit or the negative electrode of the auxiliary circuit, and the third conductive metal sheet serves as the other of the negative electrode of the main circuit and the negative electrode of the auxiliary circuit. Through the structural design of the above junction box, two circuits, the main circuit and the auxiliary circuit, can be formed, so that the function of outputting the electric energy in the stacked battery can be realized, the photoelectric conversion efficiency of the photovoltaic module can be improved, and the cost can be saved.

[0027] The utility model also provides a photovoltaic assembly, which comprises a laminated battery and the above-mentioned junction box, wherein the junction box is electrically connected to the laminated battery. The photovoltaic assembly has a high photoelectric conversion efficiency and saves costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0029] Figure 1 A schematic diagram of the structure of a junction box provided by an embodiment of the utility model;

[0030] Figure 2 The explosion of the junction box provided by the embodiment of the utility model Figure 1 ;

[0031] Figure 3 The explosion of the junction box provided by the embodiment of the utility model Figure 2 ;

[0032] Figure 4 A schematic diagram of the structure of the box body provided by an embodiment of the utility model;

[0033] Figure 5 A schematic diagram of the structure of a portion of a junction box provided by an embodiment of the utility model;

[0034] Figure 6 for Figure 5 A partial enlarged view of point A in the middle.

[0035] Reference numerals

[0036] 100, box body; 110, box wall; 1101, buckle; 120, base; 130, introduction hole; 140, mounting groove; 150, fixing column; 160, boss; 170, heat dissipation chamber; 180, groove; 190, bypass diode; 200, first conductive metal sheet; 300, second conductive metal sheet; 400, third conductive metal sheet; 500, first main circuit cable; 600, first auxiliary circuit cable; 700, second main circuit cable; 800, second auxiliary circuit cable; 900, box cover. DETAILED DESCRIPTION

[0037] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved more clearly, the technical solutions of the present invention are further explained below with reference to the accompanying drawings and through specific implementation methods.

[0038] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0040] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0041] In the description of this embodiment, unless otherwise specified, the term "plurality" refers to a quantity of two or more than two.

[0042] This embodiment provides a junction box that can be adapted to the power output of the stacked cells, thereby improving the photoelectric conversion efficiency of the photovoltaic module and saving costs.

[0043] It should be noted that the laminated battery mentioned below refers to a three-terminal perovskite laminated battery, in which the first battery layer and the second battery layer are connected in parallel, and then three ports are led out. Compared with the two-port laminated battery, the three-terminal perovskite laminated battery helps to achieve balanced current distribution and improve the stability and reliability of the battery. Exemplarily, the types of three-terminal perovskite laminated batteries can be perovskite / PERC, perovskite / TOPCon, perovskite / HJT, perovskite / I BC, perovskite / CI GS, etc.

[0044] like Figure 1-Figure 6As shown, the junction box provided in this embodiment is used to electrically connect with the laminated battery (not shown in the figure), and the junction box mainly includes a box body 100, a first conductive metal sheet 200, a second conductive metal sheet 300 and a third conductive metal sheet 400 arranged in the box body 100; a first main circuit cable 500 and a first auxiliary circuit cable 600 connected to the first conductive metal sheet 200, a second main circuit cable 700 connected to the second conductive metal sheet 300, and a second auxiliary circuit cable 800 connected to the third conductive metal sheet 400. Among them, the first conductive metal sheet 200 is electrically connected to the first battery layer and the second battery layer in the laminated battery, the second conductive metal sheet 300 is electrically connected to one of the first battery layer and the second battery layer to form a main circuit; the third conductive metal sheet 400 is electrically connected to the other of the first battery layer and the second battery layer to form an auxiliary circuit.

[0045] Optionally, the first battery layer and the second battery layer in this embodiment may both be perovskite batteries, so that the stacked battery has a "perovskite stacked perovskite" structure. The first battery layer in this embodiment may be a perovskite battery, and the second battery layer may be a crystalline silicon battery, so that the stacked battery has a "perovskite stacked crystalline silicon" structure.

[0046] For the convenience of description, in this embodiment, it is explained by taking the example that the first battery layer is set as a perovskite battery and the second battery layer is set as a crystalline silicon battery.

[0047] Based on the above design, in this embodiment, the first main circuit cable 500, the first conductive metal sheet 200, the perovskite battery, the second conductive metal sheet 300, the second main circuit cable 700 and the external electrical appliances (not shown in the figure) constitute the main circuit, and the first auxiliary circuit cable 600, the first conductive metal sheet 200, the crystalline silicon battery, the third conductive metal sheet 400, the second auxiliary circuit cable 800 and the external electrical appliances constitute the auxiliary circuit. The stacked battery in this embodiment is a three-terminal structure perovskite stacked battery, that is, it has a common terminal connected to the first conductive metal sheet 200, a port connected to the second conductive metal sheet 300, and a port connected to the third conductive metal sheet 400. Optionally, the first conductive metal sheet 200 in this embodiment serves as the positive electrode of the main circuit and the positive electrode of the auxiliary circuit, the second conductive metal sheet 300 serves as the negative electrode of the main circuit, and the third conductive metal sheet 400 serves as the negative electrode of the auxiliary circuit. Through the structural design of the above-mentioned junction box, two circuits, the main circuit and the auxiliary circuit, can be formed, so that the electric energy in the stacked battery can be output, the photoelectric conversion efficiency of the photovoltaic module can be improved, and the cost can be saved. In addition, when the two batteries in the stacked battery (i.e., the perovskite battery and the crystalline silicon battery) have a current mismatch, the mismatched current can be shunted to the auxiliary circuit and circulated into the main circuit to realize the reuse of the current, which greatly reduces the power loss and saves costs.

[0048] It can be understood that the first conductive metal sheet 200 in this embodiment is electrically connected to both the perovskite cell and the crystalline silicon cell in the stacked cell, the second conductive metal sheet 300 can be electrically connected to the perovskite cell, and the third conductive metal sheet 400 is electrically connected to the crystalline silicon cell. Of course, relevant technicians can also electrically connect the second conductive metal sheet 300 to the crystalline silicon cell and the third conductive metal sheet 400 to the perovskite cell. Thereby improving the flexible adaptability of the junction box, making the junction box applicable to different types of stacked cells, saving costs.

[0049] Since the theoretical efficiency limit of the perovskite cell is higher than that of the crystalline silicon cell, and the spectral response range of the perovskite cell is wider, it can absorb more wavelengths of light, while the crystalline silicon cell has a higher absorption efficiency only within a specific wavelength range. Therefore, in this embodiment, preferably, the second conductive metal sheet 300 is electrically connected to the perovskite cell, and the third conductive metal sheet 400 is electrically connected to the crystalline silicon cell, so that the main circuit includes the perovskite cell and the auxiliary circuit includes the crystalline silicon cell, thereby improving the photoelectric conversion efficiency of the stacked cell and saving costs.

[0050] It should be noted that the power generation principle and internal specific structure of the stacked battery in this embodiment are conventional technologies in the photovoltaic field, so they will not be described in detail here.

[0051] In this embodiment, the ends of the first main circuit cable 500, the first auxiliary circuit cable 600, the second main circuit cable 700 and the second auxiliary circuit cable 800 are all connected with connectors, which facilitates the electrical connection with the first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400, improves the reliability, stability and convenience of the connection, and improves the assembly efficiency.

[0052] like Figure 4 As shown, the box body 100 in this embodiment includes a box wall 110 and a base 120. The box wall 110 is arranged on the base 120 around the edge of the base 120 and is arranged to form a mounting cavity. The outer edge of the base 120 protrudes from the outer side wall of the box wall 110. In this way, the mechanical strength of the junction box can be increased to a certain extent, and the heat dissipation performance and waterproof performance can be improved. At the same time, it can also facilitate the installation and maintenance of the junction box, making the junction box more stable and less prone to shaking or displacement. Exemplarily, the thickness of the box wall 110 and the base 120 can be set to 1.5mm to 2mm, and the outer edge of the base 120 protrudes from the outer edge of the box wall 110 by 2mm to 3mm.

[0053] like Figure 4As shown, the base 120 in this embodiment is provided with an introduction hole 130, which is configured to allow the busbar (not shown) of the laminated battery to pass through. Specifically, the busbars at the three ports of the laminated battery can pass through the introduction hole 130 to be electrically connected to the first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400 in the box body 100 respectively. The shape and size of the introduction hole 130 are not limited in this embodiment.

[0054] The installation cavity in this embodiment includes an installation cavity, and heat dissipation cavities 170 are respectively provided on both sides of the installation cavity, and the first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400 are arranged in the installation cavity. The setting of the heat dissipation cavity 170 can disperse the hot air in the box body 100, reduce the temperature of the junction box, and improve the heat dissipation effect.

[0055] Exemplarily, in this embodiment, two heat dissipation chambers 170 may be provided, and the two heat dissipation chambers 170 are located on opposite sides of the junction box to improve the heat dissipation effect of the junction box.

[0056] like Figure 4 As shown, a plurality of mounting grooves 140 are provided in the mounting chamber in this embodiment. The mounting grooves 140 are located in the space enclosed by the box wall 110 and the base 120 . The mounting grooves 140 are configured to install a first conductive metal sheet 200 , a second conductive metal sheet 300 and a third conductive metal sheet 400 .

[0057] Specifically, in this embodiment, three mounting slots 140 are provided, and one is provided for each of the first conductive metal sheet 200, the second conductive metal sheet 300, and the third conductive metal sheet 400. The three mounting slots 140 are respectively provided to install the first conductive metal sheet 200, the second conductive metal sheet 300, and the third conductive metal sheet 400. At least one fixing column 150 is provided in each mounting slot 140, and fixing holes are provided on the first conductive metal sheet 200, the second conductive metal sheet 300, and the third conductive metal sheet 400. The fixing holes are adapted to be connected with the fixing columns 150, so as to realize the stable installation of the first conductive metal sheet 200, the second conductive metal sheet 300, and the third conductive metal sheet 400, and avoid displacement or shaking.

[0058] Furthermore, in this embodiment, the fixing hole is set as a circular hole, the fixing column 150 is set as a circular column, and the height of the fixing column 150 is greater than the thickness of the first conductive metal sheet 200 , the second conductive metal sheet 300 and the third conductive metal sheet 400 .

[0059] like Figure 4As shown, in this embodiment, a plurality of spaced bosses 160 are provided in the installation chamber, a mounting groove 140 is formed between two adjacent bosses 160, the heights of the first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400 are all lower than the height of the boss 160, and the height of the box wall 110 is higher than the height of the boss 160. In this way, the bottom wall of the two adjacent bosses 160, the mounting groove 140 and the box wall 110 are surrounded to form a glue filling area. When the junction box is bonded to the back plate of the photovoltaic module, and the bus bar is welded to the corresponding first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400, the operator can fill the glue filling area with glue, so that the glue can seal and cover the bus bar, the first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400, thereby improving the waterproof and moisture-proof performance of the junction box.

[0060] Optionally, the glue potting process in this embodiment may use organic silicon sealant.

[0061] In this embodiment, the heat dissipation chamber 170 is surrounded by the boss 160, the box wall 110 and the base 120. The boss 160 can be used as the cavity wall of the heat dissipation chamber 170, and the space in the box body 100 is divided into the installation chamber and the heat dissipation chamber 170, and then the glue filling area is defined in the installation chamber, thereby saving the glue filling amount of the organic silicon sealant and saving costs. There is no need to fill the entire box body 100 with glue in the prior art, which improves the working efficiency and achieves the purpose of saving costs.

[0062] It is understandable that the junction box in this embodiment only needs to fill the glue filling area (conductive area) with glue, and there is no need to fill the heat dissipation chamber 170 with glue, which not only ensures the safety of circuit connection and prevents water vapor intrusion, but also reduces the amount of glue filling and reduces costs. In addition, the provision of the heat dissipation chamber 170 ensures that there is enough area in the junction box for heat dissipation, avoids heat concentration, and improves safety.

[0063] like Figure 2-Figure 4 As shown, the junction box in this embodiment includes a bypass diode 190 disposed in the mounting chamber. Specifically, a groove 180 for accommodating the bypass diode 190 is disposed on the boss 160, and one end of the bypass diode 190 is connected to the first conductive metal sheet 200, and the other end is connected to the second conductive metal sheet 300. The arrangement of the bypass diode 190 has the following advantages:

[0064] First, to prevent the hot spot effect: Bypass diode 190 can effectively prevent the cells from being burned due to the hot spot effect. When some cells in the photovoltaic module cannot work properly due to shading, they may become loads and generate severe heat, which is the so-called hot spot effect. The existence of bypass diode 190 can bypass these failed cells from the main circuit to prevent them from being damaged by heat, thereby protecting the entire photovoltaic module.

[0065] Second, power loss is reduced: the bypass diode 190 provides a low impedance path, allowing current to pass smoothly, reducing power loss caused by battery failure or shielding.

[0066] The third is to protect the battery cell: the bypass diode 190 can prevent the generation of reverse current, ensuring that the current in the photovoltaic module can only flow from the positive electrode to the negative electrode of the battery cell, thereby protecting the battery cell from damage.

[0067] Fourth, improve system stability: In a photovoltaic module, the current output of some cells may decrease due to uneven loads between cells or cell aging. The bypass diode 190 can bypass these cells with smaller output, making the current output of the entire photovoltaic module system more stable.

[0068] Optionally, the bypass diode 190 in this embodiment can be set to one, two, three or the like, and a plurality of bypass diodes 190 are arranged in parallel.

[0069] like Figure 1-Figure 3 As shown, the junction box in this embodiment also includes a box cover 900, and a buckle 1101 is provided on the box wall 110. The buckle 1101 is snap-connected with the box cover 900, thereby realizing a snap-connection between the box body 100 and the box cover 900, preventing foreign matter from entering the box body 100 and extending the service life; at the same time, it is also convenient for later disassembly and maintenance.

[0070] This embodiment also provides a photovoltaic module, which includes a laminated cell and the above-mentioned junction box, and the junction box is electrically connected to the laminated cell. Specifically, the first conductive metal sheet 200, the second conductive metal sheet 300 and the third conductive metal sheet 400 in the junction box are electrically connected to the bus bars at the three ports in the laminated cell respectively. The photovoltaic module has a high photoelectric conversion efficiency and saves costs.

[0071] Obviously, the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

[0072] Note that in the description of this specification, the reference terms "some embodiments", "other embodiments", etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

Claims

1. A junction box, characterized in that: The junction box is used to electrically connect with the laminated battery, and the junction box includes: A box body (100), wherein a first conductive metal sheet (200), a second conductive metal sheet (300) and a third conductive metal sheet (400) are arranged inside the box body (100); A first main circuit cable (500), one end of which passes through the box body (100) and is connected to the first conductive metal sheet (200); A first auxiliary circuit cable (600), one end of which passes through the box body (100) and is connected to the first conductive metal sheet (200); A second main circuit cable (700), one end of which passes through the box body (100) and is connected to the second conductive metal sheet (300); A second auxiliary circuit cable (800), one end of which passes through the box body (100) and is connected to the third conductive metal sheet (400); The first conductive metal sheet (200) is used to be electrically connected to both the first battery layer and the second battery layer in the stacked battery; the second conductive metal sheet (300) is used to be electrically connected to one of the first battery layer and the second battery layer to form a main circuit; and the third conductive metal sheet (400) is used to be electrically connected to the other of the first battery layer and the second battery layer to form an auxiliary circuit.

2. The junction box according to claim 1, characterized in that: The box body (100) comprises a box wall (110) and a base (120); the box wall (110) is arranged on the base (120) around the edge of the base (120) and is surrounded to form an installation cavity; the outer edge of the base (120) protrudes from the outer side wall of the box wall (110).

3. The junction box according to claim 2, characterized in that: The base (120) is provided with an introduction hole (130), and the introduction hole (130) is configured to allow a bus bar of the laminated battery to pass through.

4. The junction box according to claim 2, characterized in that: The installation cavity comprises an installation cavity, heat dissipation cavities (170) are respectively arranged on both sides of the installation cavity, and the first conductive metal sheet (200), the second conductive metal sheet (300) and the third conductive metal sheet (400) are arranged in the installation cavity.

5. The junction box according to claim 4, characterized in that: A plurality of mounting grooves (140) are provided in the mounting chamber, and the mounting grooves (140) are configured to mount the first conductive metal sheet (200), the second conductive metal sheet (300), and the third conductive metal sheet (400).

6. The junction box according to claim 5, characterized in that: At least one fixing column (150) is arranged in each of the installation grooves (140), and fixing holes are provided on the first conductive metal sheet (200), the second conductive metal sheet (300) and the third conductive metal sheet (400), and the fixing holes are adapted to be connected with the fixing columns (150).

7. The junction box according to claim 5, characterized in that: A plurality of bosses (160) are arranged in the installation chamber, and the installation groove (140) is formed between two adjacent bosses (160); the heights of the first conductive metal sheet (200), the second conductive metal sheet (300) and the third conductive metal sheet (400) are all lower than the height of the bosses (160); and the height of the box wall (110) is higher than the height of the bosses (160).

8. The junction box according to claim 4, characterized in that: The junction box further comprises a bypass diode (190) arranged in the installation chamber, one end of the bypass diode (190) being connected to the first conductive metal sheet (200), and the other end of the bypass diode (190) being connected to the second conductive metal sheet (300).

9. The junction box according to any one of claims 2 to 8, characterized in that: The junction box further comprises a box cover (900), and a buckle (1101) is provided on the box wall (110), and the buckle (1101) is buckled and connected to the box cover (900).

10. A photovoltaic module, characterized in that The photovoltaic module comprises a laminated cell and a junction box according to any one of claims 1 to 9, wherein the junction box is electrically connected to the laminated cell.

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