Photovoltaic module

Abstract

The invention relates to the photovoltaic field, and provides a photovoltaic module comprising a battery string group comprising at least two battery strings distributed at intervals along a first direction; the isolation pieces are arranged on the backlight surfaces of the battery strings, and a gap is formed between the two isolation pieces located on the backlight surfaces of the two adjacent battery strings in the first direction; the bus bar is arranged on the side, away from the battery string, of the isolation piece in the second direction, and the projection, in the second direction, of the bus bar is overlapped with the projection, in the second direction, of the battery string; the bus bar is provided with a concave connecting part, at least part of the concave connecting part is located in the gap, and the concave connecting part is electrically connected with the two adjacent battery strings in the first direction through an electric connecting piece. The concave connecting part is a part of the structure of the bus bar and is not easy to deviate in the lamination process, so that the connection reliability between the bus bar and the electric connecting piece is improved.

Description

Technical Field

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

[0002] Photovoltaic modules consist of multiple cell strings, each containing at least two cells. Adjacent cell strings are electrically connected to busbars via electrical connectors. Because insulators are typically installed between the busbars and the cell strings, a height difference exists between them, hindering the formation of a stable connection. Summary of the Invention

[0003] In view of this, this application provides a photovoltaic module to help solve the problem of insufficient connection stability between the busbar and the electrical connector in the prior art.

[0004] This application provides a photovoltaic module, including a battery string assembly comprising at least two battery strings spaced apart along a first direction; an isolator disposed on the back surface of the battery strings, with a gap between two isolators located on the back surfaces of two adjacent battery strings along the first direction; a busbar disposed along a second direction on the side of the isolators away from the battery strings, the projection of the busbar in the second direction overlapping the projection of the battery strings in the second direction; the busbar having a concave connecting portion, at least a portion of which is located within the gap, and the concave connecting portion forming an electrical connection with two adjacent battery strings along the first direction via an electrical connector; the first direction and the second direction are perpendicular to each other.

[0005] In one possible implementation, the concave connecting portion has a groove, the depth H1 of which is 0.5mm to 1mm along the second direction; and / or, the width W1 of which is 0.5mm to 1mm along the first direction.

[0006] In one possible implementation, the thickness D1 of the busbar is 0.1 mm to 0.15 mm; and / or, along the first direction, the width W2 of the busbar is 8 mm to 10 mm.

[0007] In one possible implementation, the thickness D2 of the spacer is 0.2 mm to 0.36 mm along the second direction; and / or, the width W3 of the spacer is 5 mm to 13 mm along the first direction.

[0008] In one possible implementation, along the first direction, the isolator extends beyond the edge of the battery string in a direction close to the concave connector; and / or, along the first direction, the isolator extends beyond the edge of the busbar in a direction away from the concave connector.

[0009] In one possible implementation, the electrical connector is a lead-out solder strip, and each of the two adjacent battery strings along the first direction is provided with the lead-out solder strip; the lead-out solder strips and the concave connecting portion of the two adjacent battery strings are stacked in the second direction and form an electrical connection.

[0010] In one possible implementation, the electrical connector is a lead-out solder strip, and each of the two adjacent battery strings along the first direction is provided with the lead-out solder strip; the lead-out solder strips of the two adjacent battery strings are spaced apart in the third direction and respectively form an electrical connection with the concave connecting portion; the first direction intersects with the third direction.

[0011] In one possible implementation, the electrical connector is a connecting strip, with both ends of the connecting strip electrically connected to two adjacent battery strings along the first direction, and the middle part of the connecting strip electrically connected to the concave connecting portion.

[0012] In one possible implementation, when the electrical connector is connected to the backlight surface of the battery string, the electrical connector extends horizontally in the first direction, and the concave connecting portion forms an electrical connection with the electrical connector; or, when the electrical connector is connected to the light-facing surface of the battery string, the electrical connector extends horizontally in the first direction, and the concave connecting portion forms an electrical connection with the electrical connector.

[0013] In one possible implementation, when the electrical connector is connected to the light-facing side of the battery string, the electrical connector has a bent portion that extends along the second direction toward the back-facing side of the battery string; the bent portion is located between two adjacent battery strings along the first direction, and the concave connecting portion forms an electrical connection with the bent portion.

[0014] In one possible implementation, the spacing between two adjacent battery strings along the first direction is 2mm to 4mm.

[0015] In this application, the concave connecting portion is used to form an electrical connection with two adjacent battery strings along a first direction via electrical connectors. Since the concave connecting portion is part of the busbar's own structure, it has a reliable connection with the main body of the busbar and is less prone to shifting during lamination. This improves the connection reliability between the busbar and the electrical connector, thereby increasing the production yield of the photovoltaic module and ensuring that the output power of the photovoltaic module reaches the expected effect. Furthermore, when the busbar and the electrical connector pass through the concave connecting portion extending along a second direction, the electrical connector can connect to the busbar without bending, reducing the risk of breakage or damage to the electrical connector, thus further improving the electrical reliability and production yield of the photovoltaic module. Along the first direction, there is a gap between two isolators located on the back surface of two adjacent battery strings, and at least a portion of the concave connecting portion is located within the gap. The two isolators can limit the concave connecting portion in the first direction, reducing the risk of shifting and ensuring a stable electrical connection between the busbar and the electrical connector. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a cross-sectional structural diagram of the photovoltaic module provided in the embodiments of this application; Figure 2 This is a top view of the photovoltaic module provided in the embodiments of this application; Figure 3 for Figure 2 A schematic diagram showing the connection between the busbar and two adjacent battery strings; Figure 4 for Figure 3 A schematic cross-sectional view of the busbar and two adjacent battery strings in the first embodiment; Figure 5 for Figure 4 A schematic diagram of the cross-sectional structure of the busbar in the diagram; Figure 6 for Figure 3 A schematic cross-sectional view of the busbar and two adjacent battery strings in the second embodiment; Figure 7 for Figure 3 A schematic diagram of the cross-sectional structure of the busbar and two adjacent battery strings in the third embodiment; Figure 8 for Figure 2A schematic diagram of the connection between the busbar and two adjacent battery strings in another embodiment; Figure 9 for Figure 8 A schematic cross-sectional view of the busbar and two adjacent battery strings in the first embodiment; Figure 10 for Figure 8 A schematic cross-sectional view of the busbar and two adjacent battery strings in the second embodiment; Figure 11 for Figure 8 A schematic diagram of the cross-sectional structure of the busbar and two adjacent battery strings in the third embodiment; Figure 12 for Figure 8 A schematic cross-sectional view of the busbar and two adjacent battery strings in the fourth embodiment; Figure 13 for Figure 8 A schematic diagram of the cross-sectional structure of the busbar and two adjacent battery strings in the fifth embodiment; Figure 14 for Figure 8 The cross-sectional structure diagram of the busbar and two adjacent battery strings in the sixth embodiment.

[0018] Figure label: 100-Battery Module; 200-front plate; 300 - Front encapsulation layer; 400 - Backside encapsulation layer; 500-backplate; 10-Battery string pack; 1- Battery string; 11-Battery Cell; 12-Spindle strips; 2-Isolation component; 201-Gap; 3-Busbar; 31-Concave connecting part; 32-groove; 4-Electrical connections; 401 - Lead-out solder strip; 402 - Connecting solder strip; 41-Bend section.

[0019] 5-Channel zone. Detailed Implementation

[0020] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0021] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0022] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0024] It should be noted that the directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when it is mentioned that an element is connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected to the other element "upper" or "lower" through an intermediate element.

[0025] This application provides a photovoltaic module, such as... Figure 1 As shown, the photovoltaic module includes a cell module 100, a front panel 200, a front encapsulation layer 300, a rear encapsulation layer 400, and a back panel 500. The front panel 200 and the back panel 500 together sandwich the front encapsulation layer 300, the cell module 100, and the rear encapsulation layer 400, and form the photovoltaic module through lamination. The front encapsulation layer 300 is used to protect the light-facing side of the cell module 100, and the rear encapsulation layer 400 is used to protect the backlight side of the cell module 100. At the same time, during the lamination process of the photovoltaic module, the front encapsulation layer 300 and the rear encapsulation layer 400 are used to encapsulate and protect the cell module 100, preventing the external environment from affecting the performance of the cell module 100, and also to bond the front panel 200, the back panel 500, and the cell module 100 into a whole.

[0026] The front panel 200 and the back panel 500 can be made of light-transmitting materials. The materials for the front panel 200 and the back panel 500 can be either rigid materials such as tempered glass, polyethylene terephthalate (PET), or polycarbonate (PC), or flexible materials such as polyvinyl fluoride (PVF), ethylene-tetrafluoroethylene copolymer (ETFE), or polyvinylidene fluoride (PVDF). The materials for the front panel 200 and the back panel 500 can be the same or different. The front encapsulation layer 300 and the back encapsulation layer 400 are adhesive films. The material of the adhesive film can be one of the following: ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), polyvinyl butyral (PVB), etc. The front encapsulation layer 300 and the back encapsulation layer 400 can also be EPE film (EVA-POE-EVA co-extrusion structure) or EP film (EVA-EP co-extrusion structure). The materials of the front encapsulation layer 300 and the back encapsulation layer 400 can be the same or different. The surface of the front panel 200 facing the front encapsulation layer 300 can be provided with a concave-convex structure to increase the utilization rate of incident light. Similarly, the surface of the back panel 500 facing the back encapsulation layer 400 can also be provided with a concave-convex structure to increase the utilization rate of incident light.

[0027] In some embodiments, the photovoltaic module further includes a junction box (not shown in the figure), which is disposed on the outside of the back panel 500. The junction box contains a diode, and the two ends of the diode are connected in reverse parallel with the battery string through lead wires to avoid exceeding the reverse bias limit of the battery and damaging the photovoltaic module.

[0028] In some embodiments, such as Figure 2 As shown, the battery module 100 includes multiple battery string groups 10 spaced apart along a third direction Y, and each battery string group 10 includes at least two battery strings 1 spaced apart along a first direction X. Combined with... Figure 3 As shown, the battery string 1 includes multiple battery cells 11 arranged at intervals along a first direction X. Two adjacent battery cells 11 in the same battery string 1 are connected in series by a series bonding strip 12. In this embodiment, there are no restrictions on the number of battery string groups 10, the number of battery strings 1 in each battery string group 10, or the number of battery cells 11 in each battery string 1. These can be adjusted according to the photovoltaic module layout and output power requirements.

[0029] It should be noted that the first direction X and the third direction Y are perpendicular to each other. In the embodiments of this application, one of the first direction X and the third direction Y is the length direction of the photovoltaic module, and the other is the width direction of the photovoltaic module.

[0030] In some embodiments, such as Figure 2 As shown, the photovoltaic module also includes a busbar 5, which is located on the outer edge of the battery module 100, that is, the battery module 100 is provided with the busbar 5 on one or both sides in the first direction X. Along the first direction X, the end of the battery string 1 away from the busbar 3 is electrically connected to the busbar 5. Two adjacent battery string groups 10 along the third direction Y can be electrically connected to the busbar 5 respectively, so that the two adjacent battery string groups 10 are connected in series or in parallel.

[0031] In some embodiments, the spacing between two adjacent battery strings 1 along the first direction X is 2mm to 4mm. This can reduce the spacing between battery strings 1 so that more battery cells 11 can be set in the battery strings 1, or the size of the battery cells 11 in the first direction X can be increased, thereby improving the effective light-receiving area of ​​the photovoltaic module and thus increasing the input power of the photovoltaic module.

[0032] Optionally, the spacing between two adjacent battery strings 1 can be 2mm to 3mm, specifically 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3mm, or other values ​​within the above range. This application embodiment does not limit this.

[0033] Optionally, the spacing between two adjacent battery strings 1 can be 3mm to 4mm, specifically 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm or 4mm, or other values ​​within the above range. This application embodiment does not limit this.

[0034] In some embodiments, the battery cell 11 can be a sliced ​​battery, specifically a two-slice battery, a three-slice battery, a four-slice battery, or an eight-slice battery. This application embodiment does not limit this.

[0035] This embodiment does not limit the type of battery cell 11. The types of battery cell 11 include, but are not limited to, passivated emitter rear cell (PERC), tunnel oxide passivated contact (TOPCon), intrinsic thin-film heterojunction (HJT), perovskite cell, etc.

[0036] For PERC cells, along their thickness direction, the PERC cell sequentially includes a front-surface silver electrode, a front-surface silicon nitride passivation layer, a phosphorus emitter layer, a P-type substrate silicon layer, a localized aluminum back field, a metallic aluminum back electrode, and a back passivation layer (Al2O3 / SiNx). PERC cells use a passivation film to passivate the back side, replacing the all-aluminum back field, enhancing light reflection within the silicon substrate, reducing the recombination rate on the back side, and improving the cell efficiency by 0.5%-1%.

[0037] For TOPCon cells, along their thickness direction, the TOPCon cell sequentially includes a silver electrode, a front-surface silicon nitride passivation layer, a boron-doped emitter, an N-type substrate silicon layer, a diffused doped layer, an ultrathin silicon oxide layer, doped polycrystalline silicon, silicon nitride, and the silver electrode. The back of the cell consists of an ultrathin silicon oxide layer (1nm~2nm) and a phosphorus-doped microcrystalline amorphous mixed Si film, which together form a passivation contact structure. This structure can block minority carrier recombination, increasing the cell's open-circuit voltage and short-circuit current. The ultrathin oxide layer allows majority carrier electrons to tunnel into the polycrystalline silicon layer while blocking minority carrier recombination. The excellent passivation effect of the ultrathin silicon oxide and heavily doped silicon film causes band bending on the silicon wafer surface, resulting in a field passivation effect. This significantly increases the probability of electron tunneling, reduces contact resistance, and improves the cell's open-circuit voltage and short-circuit current, thereby increasing the cell's conversion efficiency.

[0038] For an HJT cell, along its thickness direction, the HJT cell sequentially includes a front low-temperature silver electrode, a front conductive film, an N-type amorphous silicon film, an intrinsic amorphous silicon film, an N-type substrate silicon layer, an intrinsic amorphous silicon film, a P-type amorphous silicon film, a back conductive film, and a back low-temperature silver electrode.

[0039] For a perovskite solar cell, along its thickness direction, it sequentially comprises a substrate material, a conductive thin film, an electron transport layer (titanium dioxide), a perovskite absorption layer (hole transport layer), and a metal cathode. Perovskite materials possess a high light absorption coefficient and a long carrier diffusion distance. After the photons absorbed by the perovskite material are converted into electrons, they are easily collected by the electrodes with minimal loss, thus generating high photogenerated voltage and current, resulting in high photoelectric conversion efficiency.

[0040] Figure 3 This is a partial structural diagram of the light-facing surface of the battery string group 10. In some embodiments, such as... Figure 3 As shown, the photovoltaic module also includes a busbar 3, which is disposed on the back surface of the cell string 1. Two adjacent cell strings 1 along the first direction X are electrically connected to the busbar 3 through an electrical connector 4, so that the two adjacent cell strings 1 are connected in series or in parallel. Specifically, the projection of the busbar 3 in the second direction Z overlaps with the projection of the cell string 1 in the second direction Z, that is, part of the structure of the busbar 3 is hidden on the back surface of the cell string 1, and another part of the structure is located between two adjacent cell strings 1 along the first direction X. When the busbar 3 is disposed in the above manner, the overall size of the busbar 3 and the cell string 1 in the first direction X can be reduced, so that more cells 11 can be arranged in a limited space, or the size of the cell 11 in the first direction X can be increased, thereby improving the screen ratio of the photovoltaic module and thus improving the output power of the photovoltaic module.

[0041] In the above embodiments, combined with Figure 2 As shown, two adjacent battery string groups 10 along the third direction Y can be electrically connected to the same busbar 3, so that the two adjacent battery string groups 10 along the third direction Y can be electrically connected through the busbar 3.

[0042] It should be noted that the second direction Z is perpendicular to the first direction X. In this embodiment, the second direction Z can specifically be the thickness direction of the photovoltaic module.

[0043] In some embodiments, such as Figure 3 As shown, the photovoltaic module also includes an isolator 2, which is disposed on the back surface of the cell string 1 and located between the cell string 1 and the busbar 3. That is, along the second direction Z, the busbar 3 is disposed on the side of the isolator 2 away from the cell string 1. The isolator 2 can provide insulation between the grid lines on the back surface of the cell 11 and the busbar 3, and can also provide insulation between the string bonding strip 12 on the back surface of the cell 11 and the busbar 3, thereby reducing the risk of short circuit in the cell 11 due to contact between the busbar 3 and the cell 11, which is beneficial to improving the electrical reliability of the photovoltaic module. In addition, the isolator 2 can also act as a buffer between the busbar 3 and the cell 11, avoiding direct hard contact between the busbar 3 and the cell 11, which could cause microcracks or damage to the cell 11, thus improving the service life of the cell 11.

[0044] Specifically, the separator 2 can be one of ethylene-vinyl acetate copolymer (EVA) film, polyethylene (PE) film, polyolefin elastomer (POE) film, or polyvinyl butyral (PVB) film, or it can be made of other insulating materials. This application embodiment does not limit this.

[0045] Figure 4 This is a partial cross-sectional view of a photovoltaic module with its backside facing upwards. Figure 4 As shown, when a separator 2 is provided between the busbar 3 and the solar cell 11, a height difference will occur between the busbar 3 and the electrical connector 4 in the second direction Z, making it difficult to electrically connect the busbar 3 and the electrical connector 4. To eliminate the influence of the height difference, some existing photovoltaic module manufacturing methods choose to add a solder strip between the busbar 3 and the electrical connector 4, welding the two ends of the solder strip along the second direction Z to the busbar 3 and the electrical connector 4 respectively, so that the busbar 3 and the electrical connector 4 form an electrical connection. However, the added solder strip may shift during the lamination process, affecting the connection reliability between the busbar 3 and the electrical connector 4, and may also cause compression on the edge of the solar cell 11, leading to microcracks or damage to the solar cell 11, thereby affecting the output power and yield of the photovoltaic module.

[0046] To address the aforementioned problems, the structure of the busbar 3 has been improved in this application embodiment. For example... Figure 4 As shown, the busbar 3 is provided with a concave connecting portion 31 extending along the second direction Z. The concave connecting portion 31 is used to form an electrical connection with two adjacent battery strings 1 along the first direction X through an electrical connector 4. Since the concave connecting portion 31 is part of the structure of the busbar 3 itself, the concave connecting portion 31 has a reliable connection with the main body of the busbar 3 and is not prone to displacement during the lamination process. This helps to improve the connection reliability between the busbar 3 and the electrical connector 4, thereby improving the production yield of the photovoltaic module and ensuring that the output power of the photovoltaic module reaches the expected effect. Moreover, when the busbar 3 and the electrical connector 4 are connected through the concave connecting portion 31 extending along the second direction Z, the electrical connector 4 can be connected to the busbar 3 without bending, thereby reducing the risk of breakage and damage to the electrical connector 4, which helps to further improve the electrical reliability and production yield of the photovoltaic module.

[0047] like Figure 4 As shown, along the first direction X, there is a gap 201 between two isolators 2 located on the backlight surfaces of two adjacent battery strings 1, and at least a portion of the concave connecting portion 31 is located within the gap 201. The two isolators 2 can limit the concave connecting portion 31 in the first direction X, reducing the risk of the concave connecting portion 31 shifting and ensuring a stable electrical connection between the busbar 3 and the electrical connector 4.

[0048] In this embodiment, the concave connecting portion 31 can be formed by stamping, that is, the busbar 3 with the concave connecting portion 31 is formed by stamping and plasticizing the flat structure busbar 3. The concave connecting portion 31 has a groove 32, which gives the concave connecting portion 31 a deformation buffering effect. The concave connecting portion 31 can absorb and buffer some stress during the lamination process, reduce the stress on the edge of the battery cell 11, and thus help reduce the risk of microcracks or damage to the battery cell 11.

[0049] In some embodiments, such as Figure 4 As shown, along the first direction X, the spacer 2 extends beyond the edge of the battery string 1 in the direction close to the concave connection portion 31. That is, the spacer 2 protrudes beyond the edge of the battery cell 11 to further reduce the risk of short circuit of the battery cell 11 caused by contact between the busbar 3 and the battery cell 11, thereby helping to further improve the electrical reliability of the photovoltaic module.

[0050] In some embodiments, such as Figure 4 As shown, along the first direction X, the spacer 2 extends beyond the edge of the busbar 3 in a direction away from the concave connection portion 31. That is, the spacer 2 protrudes beyond the edge of the busbar 3 to further reduce the risk of short circuit in the battery cell 11 due to contact between the busbar 3 and the battery cell 11, or to further reduce the risk of short circuit in the battery cell 11 due to contact between the busbar 3 and the string bonding strip 12 on the battery cell 11, thereby helping to further improve the electrical reliability of the photovoltaic module.

[0051] In the embodiments of this application, such as Figure 4 As shown, two isolators 2 located on the backlight surfaces of two adjacent battery strings 1 in the same battery string group 10 are referred to as a group. Along the second direction Y, the isolators 2 may include one or more groups. When the isolators 2 include one group, the battery strings 1 and busbars 3 in multiple battery string groups 10 distributed at intervals along the second direction Y are all insulated by the same group of isolators 2. When the isolators 2 include multiple groups, the number of groups of isolators 2 can be equal to the number of battery string groups 10 in the photovoltaic module, that is, the battery strings 1 and busbars 3 in each battery string group 10 are insulated by different groups of isolators 2. Alternatively, when the isolators 2 include multiple groups, the number of groups of isolators 2 can be less than the number of battery string groups 10 in the photovoltaic module, that is, some adjacent two or more battery string groups 10 may have their battery strings 1 and busbars 3 insulated by the same group of isolators 2, while the battery strings 1 and busbars 3 in other battery string groups 10 may have their battery strings 1 and busbars 3 insulated by other groups of isolators 2.

[0052] In some embodiments, such as Figure 5As shown, along the second direction Z, the depth H1 of the groove 32 is 0.5mm to 1mm. If H1 is too small (e.g., less than 0.5mm), the concave connecting part 31 will not extend deep enough into the gap 201, failing to form a sufficient contact area with the electrical connector 4, thus preventing a stable and reliable electrical connection between the busbar 3 and the electrical connector 4. Moreover, when the concave connecting part 31 extends insufficiently into the gap 201, the isolation members 2 on both sides cannot effectively limit the concave connecting part 31, and the concave connecting part 31 still has the risk of displacement, thus reducing the stability of the busbar 3. If H1 is too large (e.g., greater than 1mm), the concave connecting part 31 will extend too deep into the gap 201, increasing the stress exerted by the concave connecting part 31 on the electrical connector 4, which may also compress other components in the photovoltaic module, affecting the structural strength and stability of the photovoltaic module.

[0053] Therefore, when the depth H1 of the groove 32 is 0.5mm~1mm, it can ensure a reliable and effective electrical connection between the busbar 3 and the electrical connector 4, improve the structural stability of the busbar 3, and reduce the stress between the busbar 3 and other components, thereby improving the electrical reliability and structural stability of the photovoltaic module.

[0054] Optionally, the depth H1 of the groove 32 is 0.5mm to 0.8mm, specifically 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm or 0.8mm, or other values ​​within the above range. This application embodiment does not limit this.

[0055] Optionally, the depth H1 of the groove 32 is 0.8mm to 1mm, specifically 0.8mm, 0.85mm, 0.9mm, 0.95mm or 1mm, or other values ​​within the above range. This application embodiment does not limit this.

[0056] In some embodiments, such as Figure 5As shown, along the first direction X, the width W1 of the groove 32 is 0.5mm to 1mm. If W1 is too small (e.g., less than 0.5mm), the connection area between the concave connecting part 31 and the electrical connector 4 will be too small, resulting in a failure to form a stable and reliable electrical connection between the busbar 3 and the electrical connector 4. Moreover, if the width of the groove 32 is too narrow, the distance between it and the side spacers 2 will be too large, resulting in the concave connecting part 31 and the side spacers 2 failing to form an effective limiting in the first direction X. The concave connecting part 31 is prone to shaking during the lamination process, thus reducing the stability of the busbar 3. If W1 is too large (e.g., greater than 1mm), the distance between the concave connecting part 31 and the side spacers 2 will be too small, making assembly inconvenient. Furthermore, the stress between the concave connecting part 31 and the spacers 2 will increase during the lamination process, making the concave connecting part 31 prone to deformation, which will affect the structural stability of the busbar 3.

[0057] Therefore, when the width W1 of the groove 32 is 0.5mm~1mm, it can ensure a reliable and effective electrical connection between the busbar 3 and the electrical connector 4, and also improve the structural stability of the busbar 3.

[0058] Optionally, the width W1 of the groove 32 is 0.5mm to 0.8mm, specifically 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm or 0.8mm, or other values ​​within the above range. This application embodiment does not limit this.

[0059] Optionally, the width W1 of the groove 32 is 0.8mm to 1mm, specifically 0.8mm, 0.85mm, 0.9mm, 0.95mm or 1mm, or other values ​​within the above range. This application embodiment does not limit this.

[0060] In some embodiments, such as Figure 5 As shown, the thickness D1 of the busbar 3 is 0.1mm to 0.15mm. If D1 is too small (e.g., less than 0.1mm), the structural strength of the busbar 3 will be insufficient, and the busbar 3 will be prone to deformation or damage during the lamination process. On the other hand, with the width of the busbar 3 remaining unchanged, a small D1 will result in an excessively large cross-sectional area of ​​the busbar 3, thereby increasing the resistance of the busbar 3 and consequently reducing the output power of the photovoltaic module. If D1 is too large (e.g., greater than 0.15mm), it will increase the difficulty of the stamping process of the busbar 3 and make it difficult to form the concave connection part 31. Moreover, a large D1 will also increase the weight and cost of the busbar 3.

[0061] Therefore, when the thickness D1 of the busbar 3 is 0.1mm~0.15mm, the rigidity of the busbar 3 is moderate. This ensures that the busbar 3 has sufficient structural strength and facilitates the formation of the concave connection part 31 by stamping. It also avoids excessive resistance in the busbar 3, which is beneficial to improving the structural stability and electrical reliability of the busbar 3. In addition, it can also appropriately reduce the weight and production cost of the busbar 3.

[0062] Optionally, the thickness D1 of the busbar 3 can be 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm or 0.15mm, or other values ​​within the above range. This application embodiment does not limit this.

[0063] It should be noted that the thickness of the busbar 3 provided in this embodiment is uniform, that is, the thickness of the busbar 3 at any point is D1, which is also the thickness of the bottom wall and side wall of the concave connection 31 is D1.

[0064] In some embodiments, such as Figure 4 As shown, along the first direction X, the width W2 of the busbar 3 is 8mm to 10mm. W2 specifically refers to the distance from one end to the other of the busbar 3, which has been stamped and formed with concave connecting portions 31, in the first direction X. If W2 is too small (for example, less than 8mm), the width of the portion of the busbar 3 located on both sides of the concave connecting portion 31, which is used to overlap the separator 2, will be too small, which is not conducive to the stable installation of the busbar 3. On the other hand, with the thickness of the busbar 3 remaining unchanged, a small W2 will result in an excessively large cross-sectional area of ​​the busbar 3, thereby increasing the resistance of the busbar 3 and consequently reducing the output power of the photovoltaic module. If W2 is too large (for example, greater than 10mm), it will increase the weight and cost of the busbar 3.

[0065] Therefore, when the width W2 of busbar 3 is 8mm~10mm, it can ensure the installation stability of busbar 3 and avoid excessive resistance, which is beneficial to improving the electrical reliability of busbar 3. In addition, it can also appropriately reduce the weight and production cost of busbar 3.

[0066] Optionally, the width W2 of the busbar 3 is 8mm to 9mm, specifically 8mm, 8.1mm, 8.2mm, 8.3mm, 8.4mm, 8.5mm, 8.6mm, 8.7mm, 8.8mm, 8.9mm or 9mm, or other values ​​within the above range. This application embodiment does not limit this.

[0067] Optionally, the width W2 of the busbar 3 is 9mm to 10mm, specifically 9mm, 9.1mm, 9.2mm, 9.3mm, 9.4mm, 9.5mm, 9.6mm, 9.7mm, 9.8mm, 9.9mm or 10mm, or other values ​​within the above range. This application embodiment does not limit this.

[0068] In some embodiments, such as Figure 4 As shown, along the second direction Z, the thickness D2 of the separator 2 is 0.2mm~0.36mm. If D2 is too small (e.g., less than 0.2mm), the insulation and buffering performance of the separator 2 will be insufficient, and the separator 2 will be prone to damage. If D2 is too large (e.g., greater than 0.36mm), the overall thickness of the photovoltaic module will increase, and an excessively large D2 will cause excessive thermal stress generated by the separator 2 during lamination, which may cause microcracks or damage to the solar cell 11.

[0069] Therefore, when the thickness D2 of the separator 2 is 0.2mm~0.36mm, it can not only improve the structural strength and insulation performance of the separator 2, but also reduce the thermal stress of the separator 2, and appropriately reduce the total thickness and production cost of the photovoltaic module.

[0070] Optionally, the thickness D2 of the separator 2 is 0.2mm to 0.28mm, specifically 0.2mm, 0.21mm, 0.22mm, 0.23mm, 0.24mm, 0.25mm, 0.26mm, 0.27mm or 0.28mm, or other values ​​within the above range. This application embodiment does not limit this.

[0071] Optionally, the thickness D2 of the separator 2 is 0.28mm to 0.36mm, specifically 0.28mm, 0.29mm, 0.3mm, 0.31mm, 0.32mm, 0.33mm, 0.34mm, 0.35mm or 0.36mm, or other values ​​within the above range. This application embodiment does not limit this.

[0072] In some embodiments, such as Figure 4 As shown, along the first direction X, the width W3 of the separator 2 is 5mm to 13mm. If W3 is too small (e.g., less than 5mm), the separator 2 may not be able to completely isolate the busbar 3 from the battery cell 11, meaning there is a risk of contact between the busbar 3 and the battery cell 11, leading to a short circuit risk for the battery cell 11. If W3 is too large (e.g., greater than 13mm), it will increase the weight and cost of the separator 2.

[0073] Therefore, when the width W3 of the separator 2 is 5mm to 13mm, it can ensure that the separator 2 plays an effective role in isolating the busbar 3 and the cell 11 to improve the electrical reliability of the photovoltaic module, while also appropriately reducing the weight and production cost of the separator 2.

[0074] Optionally, the width W3 of the spacer 2 is 5mm to 10mm, specifically 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm or 10mm, or other values ​​within the above range. This application embodiment does not limit this.

[0075] Optionally, the width W3 of the spacer 2 is 10mm to 13mm, specifically 10mm, 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm or 13mm, or other values ​​within the above range. This application embodiment does not limit this.

[0076] In some embodiments, such as Figure 3 As shown, the electrical connector 4 can be connected to the backlight surface of the battery string 1. That is, the grid lines on the backlight surface of the battery cells 11 at the ends of two adjacent battery strings 1 are electrically connected to the busbar 3 through the electrical connector 4. Specifically, the electrical connector 4 can extend horizontally in the first direction X, and the busbar 3 is electrically connected to the electrical connector 4 through a concave connecting portion 31 extending downward in the second direction Z. In this embodiment, the number of electrical connectors 4 is not limited, and can be designed according to the electrical performance of the battery string 1 and the number of grid lines on the battery cells 11.

[0077] For the case where the electrical connector 4 is connected to the back surface of the battery string 1, the embodiments of this application provide the following three specific implementation methods, which will be described in detail below with reference to the accompanying drawings.

[0078] In the first implementation, such as Figure 4 As shown, the electrical connector 4 is a lead-out solder strip 401. Both adjacent battery strings 1 along the first direction X are provided with lead-out solder strips 401. The lead-out solder strips 401 and the concave connecting part 31 of the two adjacent battery strings 1 are stacked in the second direction Z and form an electrical connection.

[0079] In this embodiment, the electrical connector 4 is a split structure, comprising two independent lead-out solder strips 401. The two lead-out solder strips 401 are respectively used to form electrical connections with two adjacent battery strings 1, and respectively to form electrical connections with the grid lines on the backlight surface of the battery cells 11 located at the ends of the two battery strings 1. Simultaneously, the ends of the two lead-out solder strips 401 furthest from the battery strings 1 are stacked in the second direction Z to form a stable mechanical connection and a reliable electrical connection, and through this stacked structure, an electrical connection is formed with the concave connecting portion 31. In this embodiment, the concave connecting portion 31 and the two lead-out solder strips 401 are stacked along the second direction Z, achieving a mutual restraint effect among the three, which is beneficial to improving the connection reliability and structural stability between the concave connecting portion 31 and the two lead-out solder strips 401.

[0080] In the second implementation, such as Figure 6 As shown, the electrical connector 4 is a lead-out solder strip 401. Both adjacent battery strings 1 along the first direction X are provided with lead-out solder strips 401. The lead-out solder strips 401 of the two adjacent battery strings 1 are spaced apart in the third direction Y and respectively form an electrical connection with the concave connecting part 31.

[0081] In this embodiment, the electrical connector 4 is a split structure, comprising two independent lead-out solder strips 401. The two lead-out solder strips 401 are respectively used to form electrical connections with two adjacent cell strings 1, and respectively to form electrical connections with the grid lines on the backlight surface of the cell cells 11 located at the ends of the two cell strings 1. The ends of the two lead-out solder strips 401 away from the cell strings 1 are respectively electrically connected to the concave connecting portion 31, but the two lead-out solder strips 401 do not make contact with each other. This reduces the installation accuracy requirements of the lead-out solder strips 401 during assembly, which helps to reduce the manufacturing process difficulty of photovoltaic modules and improve the production efficiency of photovoltaic modules.

[0082] In the third implementation, such as Figure 7 As shown, the electrical connector 4 is a connecting strip 402. Along the first direction X, the two ends of the connecting strip 402 are electrically connected to two adjacent battery strings 1 respectively, and the middle part of the connecting strip 402 is electrically connected to the concave connecting part 31.

[0083] In this embodiment, the electrical connector 4 is an integral structure, comprising only one connecting strip 402. Both ends of the connecting strip 402 are electrically connected to the grid lines on the backlight surface of the solar cells 11 at the ends of the two cell strings 1, which not only improves the electrical reliability of the cell string assembly 10 but also enhances its mechanical connection reliability. The middle portion of the connecting strip 402 (i.e., the part where the connecting strip 402 is suspended between the two cell strings 1) is used to form an electrical connection with the concave connecting portion 31. In this embodiment, using an integral connecting strip 402 as the electrical connector 4 results in a simpler structure, facilitates the assembly of the electrical connector 4, reduces the manufacturing process difficulty of photovoltaic modules, and improves the production efficiency of photovoltaic modules.

[0084] In some embodiments, such as Figure 8 As shown, the electrical connector 4 can be connected to the light-facing surface of the battery string 1. That is, the grid lines on the light-facing surface of the battery cell 11 at the end of two adjacent battery strings 1 are electrically connected to the busbar 3 through the electrical connector 4. In this embodiment, the number of electrical connectors 4 is not limited, and can be designed according to the electrical performance of the battery string 1 and the number of grid lines on the battery cell 11.

[0085] Specifically, in some embodiments, the electrical connector 4 can extend horizontally in the first direction X, and the busbar 3 forms an electrical connection with the electrical connector 4 through a concave connecting portion 31 extending downward in the second direction Z. For the case where the electrical connector 4 is connected to the light-facing surface of the battery string 1 and extends horizontally in the first direction X, this application provides the following three specific implementation methods, which will be described in detail below with reference to the accompanying drawings.

[0086] In the first implementation, such as Figure 9 As shown, the electrical connector 4 is a lead-out solder strip 401. Both adjacent battery strings 1 along the first direction X are provided with lead-out solder strips 401. The lead-out solder strips 401 and the concave connecting part 31 of the two adjacent battery strings 1 are stacked in the second direction Z and form an electrical connection.

[0087] In this embodiment, the electrical connector 4 is a split structure, comprising two independent lead-out solder strips 401. The two lead-out solder strips 401 are respectively used to form electrical connections with two adjacent battery strings 1, and respectively to form electrical connections with the grid lines on the light-facing surface of the battery cells 11 located at the ends of the two battery strings 1. Simultaneously, the ends of the two lead-out solder strips 401 furthest from the battery strings 1 are stacked in the second direction Z to form a stable mechanical connection and a reliable electrical connection, and through this stacked structure, an electrical connection is formed with the concave connecting portion 31. In this embodiment, the concave connecting portion 31 and the two lead-out solder strips 401 are stacked along the second direction Z, achieving a mutual restraint effect among the three, which is beneficial to improving the connection reliability and structural stability between the concave connecting portion 31 and the two lead-out solder strips 401.

[0088] In the second implementation, such as Figure 10 As shown, the electrical connector 4 is a lead-out solder strip 401. Both adjacent battery strings 1 along the first direction X are provided with lead-out solder strips 401. The lead-out solder strips 401 of the two adjacent battery strings 1 are spaced apart in the third direction Y and respectively form an electrical connection with the concave connecting part 31.

[0089] In this embodiment, the electrical connector 4 is a split structure, comprising two independent lead-out solder strips 401. The two lead-out solder strips 401 are respectively used to form electrical connections with two adjacent battery strings 1, and respectively to form electrical connections with the grid lines on the light-facing surface of the battery cells 11 located at the ends of the two battery strings 1. The ends of the two lead-out solder strips 401 away from the battery strings 1 are respectively electrically connected to the concave connecting portion 31, but the two lead-out solder strips 401 do not make contact with each other. This reduces the installation accuracy requirements of the lead-out solder strips 401 during assembly, which helps to reduce the manufacturing process difficulty of photovoltaic modules and improve the production efficiency of photovoltaic modules.

[0090] In the third implementation, such as Figure 11 As shown, the electrical connector 4 is a connecting strip 402. Along the first direction X, the two ends of the connecting strip 402 are electrically connected to two adjacent battery strings 1 respectively, and the middle part of the connecting strip 402 is electrically connected to the concave connecting part 31.

[0091] In this embodiment, the electrical connector 4 is an integral structure, consisting of only one connecting strip 402. Both ends of the connecting strip 402 are electrically connected to the grid lines on the light-facing surfaces of the solar cells 11 at the ends of the two cell strings 1, which not only improves the electrical reliability of the cell string assembly 10 but also enhances its mechanical connection reliability. The middle portion of the connecting strip 402 (i.e., the part where the connecting strip 402 is suspended between the two cell strings 1) is used to form an electrical connection with the concave connecting portion 31. In this embodiment, using an integral connecting strip 402 as the electrical connector 4 results in a simpler structure, facilitates the assembly of the electrical connector 4, reduces the manufacturing process difficulty of photovoltaic modules, and improves the production efficiency of photovoltaic modules.

[0092] In some embodiments, the electrical connector 4 has a bent portion 41 that extends along the second direction Z toward the backlight surface of the battery string 1. The bent portion 41 is located between two adjacent battery strings 1 along the first direction X, and the concave connecting portion 31 is electrically connected to the bent portion 41. For the case where the electrical connector 4 is connected to the light-facing surface of the battery string 1 and has a bent portion 41, the embodiments of this application provide the following three specific implementations, which will be described in detail below with reference to the accompanying drawings.

[0093] In the first implementation, such as Figure 12 As shown, the electrical connector 4 has a split structure, comprising two independent lead-out solder strips 401. The two lead-out solder strips 401 are respectively used to form electrical connections with two adjacent battery strings 1, and respectively form electrical connections with the grid lines on the light-facing surface of the battery cells 11 located at the ends of the two battery strings 1. Simultaneously, each of the two lead-out solder strips 401 has a bend 41 at its end away from the battery string 1. The bends 41 of both lead-out solder strips 401 are located between two adjacent battery strings 1, and the two bends 41 are stacked in the second direction Z to form a stable mechanical connection and a reliable electrical connection, and through this stacked structure, form an electrical connection with the concave connecting portion 31.

[0094] In this embodiment, the concave connecting portion 31 and the bent portions 41 of the two lead-out solder strips 401 are stacked along the second direction Z. The three components can mutually limit each other, which helps improve the connection reliability and structural stability between the concave connecting portion 31 and the two lead-out solder strips 401. Furthermore, by providing the bent portions 41, the size of the concave connecting portion 31 in the second direction Z can be correspondingly reduced, thereby improving the structural strength of the concave connecting portion 31 and reducing the risk of deformation.

[0095] In the second implementation, such as Figure 13As shown, the electrical connector 4 has a split structure, comprising two independent lead-out solder strips 401. The two lead-out solder strips 401 are respectively used to form electrical connections with two adjacent cell strings 1, and respectively form electrical connections with the grid lines on the light-facing surface of the cell cells 11 located at the ends of the two cell strings 1. Simultaneously, each of the two lead-out solder strips 401 has a bend 41 at its end away from the cell string 1, and both bends 41 are located between two adjacent cell strings 1. The bends 41 of the two lead-out solder strips 401 are spaced apart in the third direction Y and respectively form electrical connections with the concave connecting portions 31, but the bends 41 of the two lead-out solder strips 401 do not make contact with each other. This reduces the installation accuracy requirements of the lead-out solder strips 401 during assembly, which helps to reduce the manufacturing process difficulty of photovoltaic modules and improve the production efficiency of photovoltaic modules. Furthermore, by providing the bending portion 41, the size of the concave connecting portion 31 in the second direction Z can be reduced accordingly, thereby improving the structural strength of the concave connecting portion 31 and reducing the risk of deformation of the concave connecting portion 31.

[0096] In the first implementation, such as Figure 14 As shown, the electrical connector 4 is an integral structure, consisting of only one connecting strip 402. Both ends of the connecting strip 402 are electrically connected to the grid lines on the light-facing surfaces of the solar cells 11 at the ends of the two cell strings 1, which not only improves the electrical reliability of the cell string assembly 10 but also enhances its mechanical connection reliability. A bent portion 41 is formed in the middle of the connecting strip 402 (i.e., the portion where the connecting strip 402 is suspended between the two cell strings 1), located between two adjacent cell strings 1, for electrical connection with the concave connecting portion 31. In this embodiment, using an integral connecting strip 402 as the electrical connector 4 results in a simpler structure, facilitates assembly of the electrical connector 4, reduces the manufacturing difficulty of photovoltaic modules, and improves production efficiency. Furthermore, by providing the bent portion 41, the dimensions of the concave connecting portion 31 in the second direction Z can be correspondingly reduced, thereby improving the structural strength of the concave connecting portion 31 and reducing the risk of deformation.

[0097] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A photovoltaic module, characterized in that, include: The battery string group (10) includes at least two battery strings (1) spaced apart along a first direction. The separator (2) is disposed on the back surface of the battery string (1) and has a gap (201) between the two separators (2) located on the back surface of two adjacent battery strings (1) along the first direction. Busbar (3), along the second direction, the busbar (3) is disposed on the side of the separator (2) away from the battery string (1), and the projection of the busbar (3) in the second direction overlaps with the projection of the battery string (1) in the second direction; The busbar (3) has a concave connecting portion (31), at least a portion of which is located within the gap (201), and the concave connecting portion (31) is electrically connected to two adjacent battery strings (1) along the first direction via an electrical connector (4). The first direction and the second direction are perpendicular to each other.

2. The photovoltaic module according to claim 1, characterized in that, The concave connecting part (31) has a groove (32), and the depth H1 of the groove (32) along the second direction is 0.5mm~1mm; And / or, along the first direction, the width W1 of the groove (32) is 0.5mm~1mm.

3. The photovoltaic module according to claim 1, characterized in that, The thickness D1 of the busbar (3) is 0.1mm~0.15mm; And / or, along the first direction, the width W2 of the busbar (3) is 8mm~10mm.

4. The photovoltaic module according to claim 1, characterized in that, Along the second direction, the thickness D2 of the separator (2) is 0.2mm~0.36mm; And / or, along the first direction, the width W3 of the spacer (2) is 5mm to 13mm.

5. The photovoltaic module according to claim 1, characterized in that, Along the first direction, the separator (2) extends beyond the edge of the battery string (1) in the direction close to the concave connection (31); And / or, along the first direction, the separator (2) extends beyond the edge of the busbar (3) in a direction away from the concave connection (31).

6. The photovoltaic module according to claim 1, characterized in that, The electrical connector (4) is a lead-out solder strip (401), and the two adjacent battery strings (1) along the first direction are provided with the lead-out solder strip (401). The lead-out solder strips (401) and the concave connecting portions (31) of two adjacent battery strings (1) are stacked in the second direction and form an electrical connection.

7. The photovoltaic module according to claim 1, characterized in that, The electrical connector (4) is a lead-out solder strip (401), and the two adjacent battery strings (1) along the first direction are provided with the lead-out solder strip (401). The lead-out solder strips (401) of two adjacent battery strings (1) are spaced apart in the third direction and are electrically connected to the concave connecting portion (31) respectively; The first direction intersects with the third direction.

8. The photovoltaic module according to claim 1, characterized in that, The electrical connector (4) is a connecting strip (402). Along the first direction, the two ends of the connecting strip (402) are electrically connected to two adjacent battery strings (1), and the middle part of the connecting strip (402) is electrically connected to the concave connecting part (31).

9. The photovoltaic module according to claim 1, characterized in that, When the electrical connector (4) is connected to the backlight surface of the battery string (1), the electrical connector (4) extends horizontally in the first direction, and the concave connecting part (31) forms an electrical connection with the electrical connector (4); Alternatively, when the electrical connector (4) is connected to the light-facing surface of the battery string (1), the electrical connector (4) extends horizontally in the first direction, and the concave connecting portion (31) forms an electrical connection with the electrical connector (4).

10. The photovoltaic module according to claim 1, characterized in that, When the electrical connector (4) is connected to the light-facing surface of the battery string (1), the electrical connector (4) has a bent portion (41) that extends toward the back-facing surface of the battery string (1) in the second direction. The bent portion (41) is located between two adjacent battery strings (1) along the first direction, and the concave connecting portion (31) is electrically connected to the bent portion (41).

11. The photovoltaic module according to claim 1, characterized in that, Along the first direction, the spacing between two adjacent battery strings (1) is 2mm to 4mm.

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