Photovoltaic module and preparation method thereof

Abstract

The invention relates to a photovoltaic module and a preparation method of the photovoltaic module, the photovoltaic module comprises a photovoltaic battery pack, a front packaging structure, a back packaging structure and limiting parts, the photovoltaic battery pack comprises a plurality of battery strings arranged at intervals in the width direction of the photovoltaic module, and the limiting parts are located between two adjacent battery strings. The limiting piece comprises a main body part, a first connecting part and a second connecting part, the first connecting part and the second connecting part are fixedly connected to the two ends of the main body part in the height direction of the photovoltaic module, and at least part of the main body part is clamped between the two adjacent battery strings; and the distance L1 between two adjacent groups of battery strings is more than or equal to 0.3 mm and less than or equal to 1.5 mm. According to the photovoltaic module, the reduced string spacing can be compensated to the size of the battery piece, the size of the battery piece in the width direction of the photovoltaic module is increased, the generating capacity of the photovoltaic module in the unit area is improved, the displacement of the battery string in the stacking process or the laminating process can be avoided through the arrangement of the limiting piece, and it is ensured that the spacing of the battery string is kept unchanged.

Description

[0001] This application is a divisional application, the original application's application number is 202310483557.4, the original application's filing date is April 28, 2023, and the original application's entire content is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of photovoltaic power generation, in particular to a photovoltaic module and a preparation method thereof. BACKGROUND

[0003] Solar energy is a renewable energy that can be taken without exhaustion and used without depletion. A photovoltaic module is a core part of a solar power generation system and is the most important part of the solar power generation system. Its function is to convert solar energy into electrical energy and store it in a storage battery or drive a load to work. The photovoltaic module usually includes a front encapsulation structure, a back encapsulation structure, and a photovoltaic cell group. The photovoltaic cell group is composed of multiple cell strings in series or parallel. A certain spacing is required between adjacent two cell strings to prevent short circuit caused by contact between adjacent cell strings.

[0004] In the prior art, the size of the cell sheet is small, resulting in small power generation per unit area of the photovoltaic module. Therefore, the existing photovoltaic module has the problem of low photoelectric conversion efficiency. SUMMARY

[0005] The present application provides a photovoltaic module and a preparation method thereof, which can improve the photoelectric conversion efficiency of the photovoltaic module.

[0006] The first aspect of the present application provides a photovoltaic module, which includes: a photovoltaic cell group, along the width direction of the photovoltaic module, the photovoltaic cell group includes multiple groups of spaced cell strings; a front encapsulation structure arranged on the light-receiving surface of the photovoltaic cell group, the front encapsulation structure includes a front plate and a front encapsulation layer; a back encapsulation structure arranged on the back surface of the photovoltaic cell group, the back encapsulation structure includes a back plate and a back encapsulation layer, the back plate and the front plate jointly hold the front encapsulation layer, the photovoltaic cell group, and the back encapsulation layer; a limiting piece located between adjacent two groups of the cell strings, the limiting piece includes a main body part, a first connecting part, and a second connecting part, along the height direction of the photovoltaic module, the first connecting part and the second connecting part are fixedly connected to both ends of the main body part, and at least part of the main body part is clamped between adjacent two groups of the cell strings; wherein, along the width direction of the photovoltaic module, the spacing L1 between adjacent two groups of the cell strings satisfies: 0.3mm≤L1≤1.5mm.

[0007] In a possible design, the upper surface of the first connecting part is used to connect with the front encapsulation layer, and the lower surface of the second connecting part is used to connect with the back encapsulation layer.

[0008] In a possible design, along the height direction of the photovoltaic module, the height H1 of the limiting member satisfies: 0.5mm≤H1≤3mm.

[0009] In a possible design, the limiting member is made of an insulating material, and the limiting member is one of a plastic film, transparent glass, cured insulating glue, transparent plastic plate, and transparent rubber.

[0010] In a possible design, the limiting member and the front encapsulation layer are in an integrated structure, at least one limiting member and the front encapsulation layer enclose a receiving space, and the cell string is located in the receiving space; and / or, the limiting member and the back encapsulation layer are in an integrated structure, at least one limiting member and the back encapsulation layer enclose a receiving space, and the cell string is located in the receiving space.

[0011] In a possible design, the limiting member has a Z-shaped cross section; the lower surface of the first connecting part is connected to the light-receiving surface of the cell string, and the upper surface of the second connecting part is connected to the back surface of another group of adjacent cell strings.

[0012] In a possible design, the limiting member has a C-shaped cross section; the lower surface of the first connecting part and the upper surface of the second connecting part are respectively connected to the light-receiving surface and the back surface of the same cell string.

[0013] In a possible design, a plurality of limiting members are arranged between two groups of adjacent cell strings, and the plurality of limiting members are arranged at intervals along the length direction of the photovoltaic module.

[0014] In a possible design, the cell string includes a plurality of cell pieces arranged along the length direction of the photovoltaic module, along the width direction of the photovoltaic module, the cell pieces have a first size D1, and along the length direction of the photovoltaic module, the cell pieces have a second size D2; the cell pieces are two-split pieces, and the value of D1:D2 satisfies: 2

[0015] The second aspect of the present application provides a preparation method of a photovoltaic module, the photovoltaic module including a photovoltaic cell group, a limiting member, a front encapsulation structure, and a back encapsulation structure, the limiting member including a main body part, a first connecting part, and a second connecting part, along the height direction of the photovoltaic module, the first connecting part and the second connecting part are fixedly connected to the two ends of the main body part.

[0016] The preparation method comprises the following steps:

[0017] The photovoltaic cell group, the limiting piece, the front encapsulation structure and the back encapsulation structure are provided, the photovoltaic cell group comprises a plurality of cell strings, the front encapsulation structure comprises a front plate and a front encapsulation layer, and the back encapsulation structure comprises a back plate and a back encapsulation layer.

[0018] The front plate, the front encapsulation layer, the photovoltaic cell group, the limiting piece, the back encapsulation layer and the back plate are laminated, the plurality of cell strings are arranged at intervals in the width direction of the photovoltaic module, the interval L1 between the two adjacent cell strings satisfies 0.3mm≤L1≤1.5mm, and the limiting piece is arranged between the two adjacent cell strings, and at least part of the main body part is clamped between the two adjacent cell strings.

[0019] The front plate, the front encapsulation layer, the photovoltaic cell group, the limiting piece, the back encapsulation layer and the back plate are laminated to form the photovoltaic module.

[0020] In a possible design, when the limiting piece is arranged between the two adjacent cell strings, the preparation method specifically comprises: sequentially placing the cell strings and the limiting piece in the width direction of the photovoltaic module.

[0021] In a possible design, the cross-sectional shape of the limiting piece is Z-shaped, when the cell strings and the limiting piece are sequentially placed in the width direction of the photovoltaic module, the preparation method specifically comprises: placing a group of cell strings; placing the limiting piece, connecting one of the first connecting part and the second connecting part to the cell strings; and placing another group of cell strings, connecting the cell strings to the other of the first connecting part and the second connecting part, so that the two adjacent groups of cell strings jointly clamp the main body part.

[0022] In a possible design, the cross-sectional shape of the limiting piece is C-shaped, when the limiting piece is arranged between the two adjacent cell strings, the preparation method specifically comprises: connecting the lower surface of the first connecting part and the upper surface of the second connecting part to the light-receiving surface and the back surface of the same group of cell strings respectively, so that the limiting piece is clamped on the cell strings to form a cell string assembly; and sequentially placing a plurality of cell string assemblies in the width direction of the photovoltaic module, so that the two adjacent groups of cell strings jointly clamp the main body part.

[0023] In a possible design, the limiting member is in an integrated structure with the front encapsulation layer, at least one of the limiting members and the front encapsulation layer enclose a containing space, when the limiting member is arranged between the two groups of battery strings, the preparation method specifically includes: accommodating the battery string in the containing space, so that the two groups of battery strings jointly hold the main body; and / or the limiting member is in an integrated structure with the back encapsulation layer, at least one of the limiting members and the back encapsulation layer enclose a containing space, when the limiting member is arranged between the two groups of battery strings, the preparation method specifically includes: accommodating the battery string in the containing space, so that the two groups of battery strings jointly hold the main body.

[0024] In a possible design, before the limiting member is arranged between the two groups of battery strings, the preparation method further includes: arranging a positioning adhesive tape on the two groups of battery strings, and the two ends of the positioning adhesive tape are respectively bonded to the two groups of battery strings along the width direction of the photovoltaic module; or after the limiting member is arranged between the two groups of battery strings, the preparation method further includes: arranging a positioning adhesive tape on the two groups of battery strings, and the two ends of the positioning adhesive tape are respectively bonded to the two groups of battery strings along the width direction of the photovoltaic module.

[0025] The photovoltaic module in the present application limits the spacing L1 between the adjacent battery strings to be between 0.3 mm and 1.5 mm, and in the case where the width of the photovoltaic module is unchanged, the reduced spacing between the battery strings can be compensated for in the size of the battery sheet, and the size of the battery sheet in the width direction of the photovoltaic module can be increased. The blank area of the photovoltaic module layout can be reduced, the light receiving area of the photovoltaic battery group in a unit area can be increased, the power generation capacity per unit area of the photovoltaic module can be improved, and the photoelectric conversion efficiency of the photovoltaic module can be improved. The limiting member is arranged between the two groups of battery strings, which can avoid the short circuit caused by the contact between the battery sheets of the adjacent battery strings, and the main body is clamped between the two groups of adjacent battery strings. This structure can limit the battery string in the width direction of the photovoltaic module, avoid displacement of the battery string during the lamination process or the laminating process of the photovoltaic module, and ensure that the spacing L1 between the two groups of adjacent battery strings is constant. In addition, by arranging the first connecting part and the second connecting part, the contact area between the limiting member and the battery string can be increased, and the insulation effect of the limiting member can be improved.

[0026] It should be understood that the foregoing general description and the following detailed description are only exemplary and do not limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 A cross-sectional structure schematic diagram of the photovoltaic module provided in the present application;

[0028] Figure 2top view of a photovoltaic cell group of the first kind;

[0029] Figure 3 is a cross-sectional structure schematic diagram of the photovoltaic cell group in the first embodiment in Figure 2

[0030] Figure 4 is a cross-sectional structure schematic diagram of the photovoltaic cell group in the second embodiment in Figure 2

[0031] Figure 5 is a cross-sectional structure schematic diagram of the photovoltaic cell group in the third embodiment in Figure 2

[0032] Figure 6 is a cross-sectional structure schematic diagram of the photovoltaic cell group in the fourth embodiment in Figure 2

[0033] Figure 7 is a cross-sectional structure schematic diagram of the photovoltaic cell group in the fifth embodiment in Figure 2

[0034] Figure 8 is a top view of a photovoltaic cell group of the second kind;

[0035] Figure 9 is a flow chart of preparing a photovoltaic assembly provided by the present application;

[0036] Figure 10 is a flow chart of preparing a photovoltaic assembly provided by the present application;

[0037] Figure 11 is a flow chart of preparing a photovoltaic assembly provided by the present application;

[0038] Figure 12 is a cross-sectional structure schematic diagram of the photovoltaic cell group in the sixth embodiment in Figure 2

[0039] Figure 13 is a top view of a photovoltaic cell group of the third kind;

[0040] Figure 14 is a top view of a photovoltaic cell group of the fourth kind.

[0041] Reference signs:

[0042] 1 - photovoltaic cell group;

[0043] 11 - cell string;

[0044] 111 - cell piece;

[0045] 2 - front plate;

[0046] ​​​​​​3 - front encapsulation layer;

[0047] 4 - back plate;

[0048] 5 - back encapsulation layer;

[0049] 6 - limiting member;

[0050] 61 - main body portion;

[0051] 62 - first connecting portion;

[0052] 63 - second connecting portion;

[0053] 7 - positioning adhesive tape.

[0054] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application. DETAILED DESCRIPTION

[0055] For a better understanding of the technical solutions of the present application, the embodiments of the present application are described in detail below with reference to the drawings.

[0056] It should be clear that the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0057] The terms used in the embodiments of the present application are only for the purpose of describing the specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0058] It should be understood that the term "and / or" used herein is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0059] It should be noted that the "up", "down", "left", "right" and other directional words described in the embodiments of the present application are described from the angle shown in the drawings, and should not be understood as a limitation on the embodiments of the present application. In addition, in the context, it should also be understood that when referring to an element connected to another element "on" or "under", it can not only be directly connected to another element "on" or "under", but also indirectly connected to another element "on" or "under" through an intermediate element.

[0060] The photovoltaic module comprises a front encapsulation structure, a back encapsulation structure and a photovoltaic cell group, wherein the photovoltaic cell group comprises a plurality of groups of cell strings arranged at intervals along the width direction of the photovoltaic module, the plurality of groups of cell strings are connected in series or in parallel, each group of cell strings comprises a plurality of cell pieces arranged at intervals along the length direction of the photovoltaic module, and the plurality of cell pieces are connected in series. In the prior art, the size of the cell piece is small, which leads to a small power generation per unit area of the photovoltaic module, and affects the photoelectric conversion efficiency of the photovoltaic module.

[0061] Based on the above problems, the present application provides a photovoltaic module, as shown in the drawings, Figure 1 The photovoltaic module comprises a photovoltaic cell group 1, a front encapsulation structure and a back encapsulation structure. Along the width direction X of the photovoltaic module, the photovoltaic cell group 1 comprises a plurality of groups of cell strings 11 arranged at intervals; the front encapsulation structure is arranged on the light-receiving surface of the photovoltaic cell group 1, and the front encapsulation structure comprises a front plate 2 and a front encapsulation layer 3; the back encapsulation structure is arranged on the back surface of the photovoltaic cell group 1, and the back encapsulation structure comprises a back plate 4 and a back encapsulation layer 5, and the front plate 2 and the back plate 4 jointly hold the front encapsulation layer 3, the photovoltaic cell group 1 and the back encapsulation layer 5. Wherein, along the width direction X of the photovoltaic module, the interval L1 between the two adjacent groups of cell strings 11 satisfies: 0.3mm≤L1≤1.5mm.

[0062] In this embodiment, the photovoltaic module is composed of the front plate 2, the front encapsulation layer 3, the photovoltaic cell group 1, the back encapsulation layer 5 and the back plate 4 through lamination encapsulation. Wherein, the front plate 2 is located on the light-receiving side of the photovoltaic cell group 1, used for transmitting sunlight, also used for improving the waterproof and moisture-proof ability of the photovoltaic module, and jointly seals the photovoltaic cell group 1 with the back plate 4. The front encapsulation layer 3 is used for protecting the light-receiving surface of the photovoltaic cell group 1 (the side surface of the photovoltaic cell group 1 facing the light source, used for receiving direct sunlight), and the back encapsulation layer 5 is used for protecting the back surface of the photovoltaic cell group 1 (the side surface of the photovoltaic cell group 1 away from the light source), at the same time, the front encapsulation layer 3 and the back encapsulation layer 5 are used for encapsulating and protecting the photovoltaic cell group 1 in the lamination process of the photovoltaic module, preventing the external environment from affecting the performance of the photovoltaic cell group 1, and also can bond the front plate 2, the back plate 4 and the photovoltaic cell group 1 into an integral whole. As shown in Figure 2 As shown in the drawings, each group of cell strings 11 comprises a plurality of cell pieces 111 arranged along the length direction Y of the photovoltaic module, and the interval L1 is the distance between two cell pieces 111 of the two adjacent groups of cell strings 11 aligned in position along the width direction X of the photovoltaic module. The interval L1 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm or 1.5mm, or other values within the above range, which is not limited herein.

[0063] In the preparation process of the photovoltaic module, the cell sheet 111 can expand due to the material of the cell sheet 111, and due to the vacuum extraction step in the lamination process and the material flow of the front encapsulation layer 3 and the back encapsulation layer 5, the cell string 11 can also be displaced in the width direction X of the photovoltaic module. In the case of a fixed width of the photovoltaic module, if the spacing L1 is too small (for example, less than 0.3 mm), the two adjacent cell strings 11 can be close to each other during the preparation of the photovoltaic module, so that the two adjacent cell sheets 111 in the width direction X of the photovoltaic module contact each other, causing short circuit of the photovoltaic module, and even the cell sheets 111 of the two adjacent cell strings 11 can be misaligned and overlapped, causing the cell sheet 111 to crack during lamination.

[0064] In the case of a fixed width of the photovoltaic module, if the spacing L1 is too large (for example, greater than 1.5 mm), the size of the cell sheet 111 in the width direction X of the photovoltaic module will be limited, resulting in a small effective light receiving area of the photovoltaic module, affecting the power generation per unit area of the photovoltaic module, and causing the photovoltaic module to have a low photoelectric conversion efficiency.

[0065] Therefore, the spacing L1 between the two adjacent cell strings 11 in the width direction X of the photovoltaic module should be 0.3 mm to 1.5 mm, preferably 0.3 mm to 1 mm, which can improve the photoelectric conversion efficiency of the photovoltaic module, avoid short circuit of the photovoltaic module, and ensure the yield of the photovoltaic module. In the prior art, the spacing between the adjacent cell strings 11 is usually 1.6 mm to 2.5 mm, and the photovoltaic module provided in the present application limits the spacing L1 between the adjacent cell strings 11 to 0.3 mm to 1.5 mm. In the case of a fixed width of the photovoltaic module, the reduced spacing between the cell strings can be compensated by increasing the size of the cell sheet 111 in the width direction X of the photovoltaic module. The blank area of the photovoltaic module layout can be reduced, the light receiving area of the photovoltaic cell group per unit area can be increased, the power generation per unit area of the photovoltaic module can be improved, and the photoelectric conversion efficiency of the photovoltaic module can be improved.

[0066] In the present embodiment, a plurality of cell sheets 111 are connected in series along the length direction Y of the photovoltaic module to form a cell string 11, a plurality of cell strings 11 are arranged along the width direction X of the photovoltaic module, and a plurality of cell strings 11 are connected in series or parallel to form a cell string group, and a plurality of cell string groups can be connected in parallel.

[0067] In an embodiment, the plurality of battery pieces 111 in the same battery string 11 can be connected by using a stack welding technology, i.e., the battery piece 111 is cut into a half battery piece along a direction perpendicular to the main grid line, a plurality of half battery pieces are arranged in an edge lap manner, and the overlapping width between adjacent two half battery pieces is 0.3mm-2.0mm. Then, the adjacent two half battery pieces are connected by a flexible copper-tin plated wire with a diameter of 0.1mm-0.35mm, and no main grid welding point is arranged in the overlapping area of the battery, i.e., the solder strip and the main grid of the battery are not bonded. The stack welding connection can eliminate the spacing between adjacent battery pieces 111 in the same battery string 11, which is conducive to increasing the size of the battery piece 111 along the length direction Y of the photovoltaic module, improving the effective light receiving area of the photovoltaic module, and further improving the photoelectric conversion efficiency of the photovoltaic battery pack.

[0068] In a specific embodiment, as shown in Figure 1 and Figure 3 The photovoltaic module further comprises a limiting piece 6, the limiting piece 6 is located between the adjacent two groups of battery strings 11, and the limiting piece 6 comprises a main body part 61, at least part of the main body part 61 is clamped between the adjacent two groups of battery strings 11.

[0069] The limiting piece 6 is made of an insulating material, and the limiting piece 6 is arranged between the two groups of battery strings 11, which can avoid the short circuit caused by the contact between the battery pieces 111 of the adjacent battery strings 11. Moreover, along the width direction X of the photovoltaic module, the battery strings 11 and the main body part 61 are arranged in a staggered manner, and the main body part 61 is clamped between the adjacent two groups of battery strings 11. This structure can limit the battery strings 11 in the width direction X of the photovoltaic module, avoid the displacement of the battery strings 11 during the lamination process or the laminating process of the photovoltaic module, and ensure that the spacing L1 between the adjacent two groups of battery strings 11 is constant.

[0070] In a specific embodiment, the spacer 6 is made of an insulating material, specifically, the spacer 6 is made of one of a plastic film, transparent glass, cured insulating glue, transparent plastic plate, and transparent rubber. The above-mentioned materials have good insulation effect and good light transmission effect, and do not affect the photoelectric conversion efficiency of the photovoltaic module. When the spacer 6 is made of a transparent plastic plate, the material of the spacer 6 can be one of polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polypropylene (PP), and polyvinyl chloride (PVC). When the spacer 6 is made of cured insulating glue, the material of the insulating glue can be one or more of silicone, acrylic, and epoxy resin. When the spacer 6 is made of transparent rubber, the material of the spacer 6 can be one of ethylene-propylene rubber, ethylene-vinyl acetate, chlorohydrin rubber, and butyl rubber.

[0071] Preferably, the spacer 6 is made of a plastic film, and the material of the plastic film can be one of ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), polyvinyl butyral (PVB), and the like. The plastic film can also be an EPE plastic film (EVA-POE-EVA co-extrusion structure) or an EP plastic film (EVA-EP co-extrusion structure). The spacer 6 in the form of a plastic film made of the above-mentioned materials can be melted together with the front encapsulation layer 3 and the back encapsulation layer 5 during the lamination process of the photovoltaic module. In the width direction X of the photovoltaic module, the spacer 6 can serve to connect two adjacent cell strings 11. In the height direction Z of the photovoltaic module, the spacer 6 can serve to connect the front encapsulation layer 3 and the back encapsulation layer 5.

[0072] The specific structure of the spacer 6 is not limited and can also be a hollow structure.

[0073] It should be noted that the embodiments in the present application are described by taking the case where the spacer 6 is made of a plastic film as an example, but the spacer 6 can also be made of other materials as described above, and the present application does not limit this.

[0074] Taking the case where the spacer 6 is made of a plastic film with a grammage of 300 g / m 2 The specific conditions of the yield and power of the photovoltaic module when the value of the spacing L1 is different are shown in the following table:

[0075]

[0076]

[0077] As shown in the above table, when the interval L1≤0.3mm (for example, L1=0.2mm or L1=0.1mm), the yield of the photovoltaic module will be greatly reduced, therefore, the interval L1 needs to be greater than 0.3mm.

[0078] In a specific embodiment, as shown in Figure 3 , along the height direction Z of the photovoltaic module, the height H1 of the limiting piece 6 satisfies: 0.5mm≤H1≤3mm. H1 can be specifically 0.5mm, 1mm, 1.5mm, 1.8mm, 2.3mm or 3mm, or other values within the above range, which are not limited herein.

[0079] When the height H1 of the limiting piece 6 is too small (for example, less than 0.5mm), the isolation effect of the limiting piece 6 on the adjacent cell strings 11 is poor, and there is still a risk of contact between the two adjacent cell strings 11; when the height H1 of the limiting piece 6 is too large (for example, greater than 3mm), it will cause bubbles in the photovoltaic module during the lamination process, affecting the packaging sealing of the photovoltaic module. Therefore, when H1 is 0.5mm-3mm, the limiting piece 6 can not only ensure the isolation effect of the limiting piece 6 on the adjacent cell strings 11, but also avoid the generation of bubbles in the photovoltaic module during the packaging process.

[0080] In a specific embodiment, as shown in Figure 4 and Figure 5 , the limiting piece 6 further comprises a first connecting part 62 and a second connecting part 63, and along the height direction Z of the photovoltaic module, the first connecting part 62 and the second connecting part 63 are fixedly connected to both ends of the main body part 61; the upper surface of the first connecting part 62 is used to connect with the front packaging layer 3, and the lower surface of the second connecting part 63 is used to connect with the back packaging layer 5.

[0081] By setting the first connecting part 62 and the second connecting part 63, the contact area of the limiting piece 6 with the cell string 11 can be increased, so as to improve the insulation effect of the limiting piece 6. During the lamination process of the photovoltaic module, the first connecting part 62 and the second connecting part 63 can play the same role as the front packaging layer 3 and the back packaging layer 5, improve the connection stability of the photovoltaic cell group 1 with the front plate 2 and the back plate 4, so as to make the photovoltaic module achieve better packaging effect.

[0082] Wherein, the size and shape of the first connecting part 62 and the second connecting part 63 are exactly the same, and the first connecting part 62, the second connecting part 63 and the main body part 61 can be an integral structure or a split structure, which is not limited in the embodiment.

[0083] Specifically, as shown in Figure 4As shown, the cross-section of the limiting member 6 is Z-shaped, the lower surface of the first connecting portion 62 is connected to the light-facing surface of the battery string 11 , and the upper surface of the second connecting portion 63 is connected to the backlight surface of another adjacent battery string 11 .

[0084] When the cross-section of the stopper 6 is Z-shaped, the first connection portion 62 can increase the contact area between the stopper 6 and the battery string 11, and the second connection portion 63 can increase the contact area between the stopper 6 and another adjacent battery string 11, which is beneficial to improving the installation stability of the stopper 6. Even if two adjacent battery strings 11 undergo a certain displacement along the width direction X of the module, the stopper 6 will not be displaced, ensuring the isolation and insulation effect of the stopper 6 between the two adjacent battery strings 11. During the stacking process of the photovoltaic module, the first connection portion 62 can be clamped by the front encapsulation layer 3 and the battery string 11, and the second connection portion 63 can be clamped by the back encapsulation layer 5 and another adjacent battery string 11, further fixing the position of the stopper 6.

[0085] Preferably, the first connecting portion 62 , the second connecting portion 63 and the main body 61 are an integrated structure, and are bent to form a Z-shaped structure.

[0086] Or, as Figure 5 As shown, the cross-section of the stopper 6 is C-shaped, and the lower surface of the first connecting portion 62 and the upper surface of the second connecting portion 63 are respectively connected to the light-facing surface and the backlight surface of the same battery string 11 .

[0087] When the cross-section of the retaining member 6 is C-shaped, and both the first connecting portion 62 and the second connecting portion 63 are connected to the same cell string 11, the contact area between the retaining member 6 and the cell string 11 can be increased. The retaining member 6 is in a state of being clamped to the cell string 11, which is conducive to improving the installation stability of the retaining member 6 and ensuring the isolation and insulation effect of the retaining member 6 between two adjacent groups of cell strings 11. During the stacking process of the photovoltaic module, the first connecting portion 62 can be clamped by the front encapsulation layer 3 and the cell string 11, and the second connecting portion 63 can be clamped by the back encapsulation layer 5 and another adjacent group of cell strings 11, further fixing the position of the retaining member 6 and ensuring the isolation and insulation effect of the retaining member 6 on the cell string 11.

[0088] Preferably, the first connecting portion 62 , the second connecting portion 63 and the main body 61 are an integrated structure, and are bent to form a C-shaped structure.

[0089] like Figure 12As shown, the cross section of the limiting member 6 can also be H-shaped, the lower surface of the first connecting part 62 is connected with the light-receiving surface of the adjacent two groups of battery strings 11 respectively, and the upper surface of the second connecting part 63 is connected with the back surface of the adjacent two groups of battery strings 11 respectively. When this structure is adopted, the installation stability of the limiting member 6 can also be improved, and the isolation and insulation effect of the limiting member 6 on the adjacent two groups of battery strings 11 can be ensured.

[0090] Preferably, the first connecting part 62, the second connecting part 63 and the main body part 61 are integrally formed. In another specific embodiment, as shown in Figure 6 As shown, the limiting member 6 and the front encapsulation layer 3 are in an integrated structure, at least one limiting member 6 and the front encapsulation layer 3 enclose a containing space, and the battery string 11 is located in the containing space. And / or, as shown in Figure 7 As shown, the limiting member 6 and the back encapsulation layer 5 are in an integrated structure, at least one limiting member 6 and the back encapsulation layer 5 enclose a containing space, and the battery string 11 is located in the containing space.

[0091] In this embodiment, as shown in Figure 6 As shown, the limiting member 6 and the front encapsulation layer 3 can be arranged in an integrated structure, the position of the limiting member 6 on the front encapsulation layer 3 is arranged according to the size of the battery sheet 111 along the width direction X of the photovoltaic module, and in the lamination step of the photovoltaic module, the battery string 11 can be directly placed in the containing space enclosed by the front encapsulation layer 3 and the limiting member 6, and a plurality of containing spaces are used to contain a plurality of battery strings 11. Similarly, as shown in Figure 7 As shown, the limiting member 6 and the back encapsulation layer 5 can also be arranged in an integrated structure, the position of the limiting member 6 on the back encapsulation layer 5 is arranged according to the size of the battery sheet 111 along the width direction X of the photovoltaic module, and in the lamination step of the photovoltaic module, the battery string 11 can be directly placed in the containing space enclosed by the back encapsulation layer 5 and the limiting member 6, and a plurality of containing spaces are used to contain a plurality of battery strings 11.

[0092] When the limiting member 6 and the front encapsulation layer 3 and / or the back encapsulation layer 5 are in an integrated structure, on the one hand, the step of separately placing the limiting member 6 can be omitted to improve the preparation efficiency of the photovoltaic module; on the other hand, the integrated structure can ensure the position of the limiting member 6 to be fixed, and the stability of the isolation and insulation effect can be ensured.

[0093] It should be noted that when the limiting member 6 and the front encapsulation layer 3 and / or the back encapsulation layer 5 are in a split structure, the battery string 11 needs to be arranged in close contact with the limiting member 6 along the width direction X of the photovoltaic module, and the size of the limiting member 6 in the width direction X of the photovoltaic module should be equal to the size of the preset interval L1, i.e., the width of the limiting member 6 is 0.3mm-1.5mm, so as to ensure the limiting effect of the limiting member 6 on the battery string 11, avoid displacement of the battery string 11 in the process of lamination and layering of the photovoltaic module, and maintain the interval L1 between the adjacent two groups of battery strings 11 unchanged.

[0094] When the limiting member 6 and the front encapsulation layer 3 and / or the back encapsulation layer 5 are in an integrated structure, in principle, the distance between the adjacent two limiting members 6 in the width direction X of the photovoltaic module should be equal to the size of the battery piece 111, and the size of the limiting member 6 in the width direction X of the photovoltaic module should be equal to the size of the preset interval L, i.e., the width of the limiting member 6 is 0.3mm-1.5mm. However, in order to facilitate the placement of the battery string 11 into the accommodating space, the distance between the two limiting members 6 can be appropriately expanded, so as to be slightly larger than the size of the battery piece 111, i.e., when a plurality of groups of battery strings 11 are arranged, there can be a gap of 0.1mm-0.2mm between the limiting member 6 and the battery string 11 in the width direction X of the photovoltaic module. Since the position of the limiting member 6 on the front encapsulation layer 3 and / or the back encapsulation layer 5 is fixed, the gap will not affect the limiting effect of the limiting member 6 on the adjacent two groups of battery strings 11, and will not cause excessive displacement of the battery string 11 in the width direction X of the photovoltaic module, so as to maintain the interval L1 between the adjacent two groups of battery strings 11 unchanged.

[0095] Since the distance between the two limiting members 6 in the width direction X of the photovoltaic module is expanded, the width of the limiting member 6 needs to be correspondingly reduced, so as to ensure that the size of the battery piece 111 is not reduced, and therefore when the limiting member 6 and the front encapsulation layer 3 and / or the back encapsulation layer 5 are in an integrated structure, the width of the limiting member 6 is 0.1mm-1.4mm.

[0096] The size of the limiting member 6 in the length direction Y of the photovoltaic module (the length of the limiting member 6) is not limited in the present application, as shown in Figure 13 the length of the limiting member 6 can be equal to the size of the battery string 11 in the length direction Y of the photovoltaic module (the length of the battery string 11).

[0097] Alternatively, the length of the limiting member 6 can be smaller than the length of the battery string 11, and in this case, a plurality of limiting members 6 can be arranged between the adjacent two groups of battery strings 11, and the plurality of limiting members 6 are arranged at intervals in the length direction Y of the photovoltaic module. Specifically, as shown in Figure 2 and Figure 8As shown, when the length of the limiting member 6 is less than or equal to the size D2 of the battery piece 111 in the width direction Y of the photovoltaic module, the limiting member 6 can also be arranged in the following two ways in the photovoltaic module: as shown in Figure 2 As shown, along the width direction X of the photovoltaic module, the limiting member 6 is located between the 2n-1th battery piece 111 in the length direction Y of the photovoltaic module of the 2n-1th battery string 11 and the 2nth battery piece 111 in the length direction Y of the photovoltaic module of the 2nth battery string 11, and between the 2nth battery piece 111 in the length direction Y of the photovoltaic module of the 2nth battery string 11 and the 2n-1th battery piece 111 in the length direction Y of the photovoltaic module of the 2n+1th battery string 11, where n≥1.

[0098] For example, when n=1, along the width direction X of the photovoltaic module, the limiting member 6 is located between the 1th battery piece 111 in the length direction Y of the photovoltaic module of the 1th battery string 11 and the 1th battery piece 111 in the length direction Y of the photovoltaic module of the 2th battery string 11, and the limiting member 6 is also located between the 2th battery piece 111 in the length direction Y of the photovoltaic module of the 2th battery string 11 and the 2th battery piece 111 in the length direction Y of the photovoltaic module of the 3th battery string 11. That is, along the width direction X of the photovoltaic module and the length direction Y of the photovoltaic module, the limiting member 6 is arranged at intervals, and for the same battery piece 111, at most one side of the two sides of the battery piece 111 along the width direction X of the photovoltaic module is provided with the limiting member 6.

[0099] Alternatively, as shown in Figure 8 As shown, along the width direction X of the photovoltaic module, the limiting member 6 is located between the 2n-1th battery piece 111 in the length direction Y of the photovoltaic module of the 2n-1th battery string 11 and the 2nth battery piece 111 in the length direction Y of the photovoltaic module of the 2nth battery string 11, and between the 2nth battery piece 111 in the length direction Y of the photovoltaic module of the 2nth battery string 11 and the 2n-1th battery piece 111 in the length direction Y of the photovoltaic module of the 2n+1th battery string 11, where n≥1.

[0100] Taking n=1 as an example, along the width direction X of the photovoltaic module, the stopper 6 is located between the second cell 111 of the first cell string 11 in the length direction Y of the photovoltaic module and the second cell 111 of the second cell string 11 in the length direction Y of the photovoltaic module. The stopper 6 is also located between the first cell 111 of the second cell string 11 in the length direction Y of the photovoltaic module and the first cell 111 of the third cell string 11 in the length direction Y of the photovoltaic module. That is, along the width direction X and the length direction Y of the photovoltaic module, the stoppers 6 are arranged at intervals, and for the same cell 111, at most one of its two sides along the width direction X of the photovoltaic module is provided with a stopper 6.

[0101] The above two arrangements can save raw materials and reduce the cost of photovoltaic modules while ensuring that the effect of the limiting member 6 is not affected.

[0102] like Figure 14 As shown, the photovoltaic module also includes positioning tape 7, which can connect the battery cells 111 of two adjacent groups of battery strings 11 (i.e., two adjacent battery cells 111 along the width direction X of the photovoltaic module) and can limit the battery cells 111, playing the same role as the limiting member 6 in preventing the battery strings 11 from shifting. Specifically, along the width direction X of the photovoltaic module, the two ends of the positioning tape 7 are respectively adhered to the battery cells 111 of the two groups of battery strings 11. In addition, multiple positioning tapes 7 are arranged at intervals along the length direction Y of the photovoltaic module.

[0103] This embodiment does not limit the specific shape and size of the positioning tape 7 , nor the distance between two adjacent positioning tapes.

[0104] At this time, the limiter 6 can be set according to the position of the positioning tape 7, and the two do not overlap along the length direction Y of the photovoltaic component. The specific number and length of the limiter 6 can be adjusted with the position of the positioning tape 7, and this embodiment does not impose any restrictions on this.

[0105] In addition, during the lamination process of the photovoltaic module, the battery string 11 and the limiter 6 may be displaced, causing some battery cells 111 to move toward the outside of the photovoltaic module along the width direction X of the photovoltaic module, resulting in a gap of 0.3mm to 0.7mm between the battery cell 111 that is not affixed with the positioning tape 7 and the adjacent limiter 6. However, since the positioning tape 7 has a good fixing effect on the battery cell 111, the battery cell 111 affixed with the positioning tape 7 will not move.

[0106] like Figure 8As shown, along the width direction X of the photovoltaic module, the cell piece 111 has a first size D1, and the cell piece 111 has a second size D2, and the conventional technical means often uses a two-division piece (i.e. D2=1 / 2D1), a three-division piece (i.e. D2=1 / 3D1) or a four-division piece (i.e. D2=1 / 4D1) as the cell piece 111. In the conventional photovoltaic cell group 1, the number of groups of the cell string 11 is 6, the spacing between adjacent cell pieces 111 is 1.9mm, the first size D1 of the cell piece 111 is 163mm-210mm, and preferably 163mm, 182mm and 210mm.

[0107] It should be noted that the embodiments in the present application are all described by taking the case of the cell piece 111 as a two-division piece as an example, but the cell piece can also be a three-division piece or a four-division piece, which is not limited in the present application.

[0108] When the photovoltaic module adopts the structure with the limiting piece 6 described above, the spacing L1 between adjacent cell strings 11 can be reduced, so that the first size D1 can be increased, which is beneficial to improve the power of the photovoltaic module.

[0109] Taking the case that the photovoltaic cell group 1 includes 6 groups of cell strings 11 arranged side by side, and the spacing L1 between adjacent cell strings 11 is 0.3mm-1.5mm as an example, the increase value range of the first size D1 of the cell piece 111 in each group of cell strings 11 can be calculated according to [5×(1.9-L1)] / 6, wherein 5 in the above formula represents that there are 5 spacings L1 in the photovoltaic cell group when 6 groups of cell strings 11 are arranged side by side. Therefore, when the number of groups of cell strings 11 in the photovoltaic cell group 1 is n, there are n-1 spacings L1 in the photovoltaic cell group 1, and the increase value of the first size D1 can be calculated by the formula [(n-1)×(1.9-L1)] / n.

[0110] When the battery piece 111 is a two-split piece and the first dimension D1 is 163 mm, the second dimension D2 is 81.5 mm, and according to the above formula, the increased range of the first dimension D1 (the decimal part is rounded to 0.5 mm) is 0.5 mm to 1.5 mm. Therefore, when the first dimension D1 of the original battery piece 111 is 163 mm, the increased first dimension D1 is 163.5 mm to 164.5 mm, and specifically can be 163.5 mm, 163.7 mm, 163.9 mm, 164.1 mm, 164.3 mm, 164.5 mm, and the second dimension D2 of the battery piece 111 remains unchanged at 81.5 mm; when the first dimension D1 of the original battery piece 111 is 182 mm, the increased first dimension D1 is 182.5 mm to 183.5 mm, and specifically can be 182.5 mm, 182.7 mm, 182.9 mm, 183.1 mm, 183.3 mm, 183.5 mm, or other values within the above range, and the second dimension D2 of the battery piece 111 remains unchanged at 91 mm; when the first dimension D1 of the original battery piece 111 is 210 mm, the increased first dimension D1 is 210.5 mm to 211.5 mm, and specifically can be 210.5 mm, 210.7 mm, 210.9 mm, 211.1 mm, 211.3 mm, 211.5 mm, or other values within the above range, and the second dimension D2 of the battery piece 111 remains unchanged at 105 mm.

[0111] According to the above calculation, when the original battery piece 111 is a two-split piece and the first dimension D1 is 163 mm to 210 mm, the increased first dimension D1 is 163.5 mm to 211.5 mm, and specifically can be 163.5 mm, 170 mm, 182 mm, 190 mm, 200 mm, 210 mm, or 211.5 mm, and the value of D1:D2 satisfies 2 < D1:D2 ≤ 2.02. Specifically, it can be 2.001, 2.006, 2.012, 2.015, or 2.02, or other values within the above range, which is not limited in the present embodiment.

[0112] Similarly, when the battery piece 111 is a three-split piece and the first dimension D1 is 163 mm to 210 mm, the increased first dimension D1 is 163.5 mm to 211.5 mm, and the value of D1:D2 satisfies 3.01 ≤ D1:D2 ≤ 3.03, specifically can be 3.01, 3.016, 3.023, 3.025, or 3.03, or other values within the above range, which is not limited in the present embodiment.

[0113] Similarly, when the battery piece 111 is a quarter piece, and the first size D1 is 163mm-210mm, the increased first size D1 is 163.5mm-211.5mm, and the value of D1:D2 satisfies: 4.01≤D1:D2≤4.04, which can be 4.01, 4.016, 4.022, 4.036 or 4.04, or other values in the above range, and the present embodiment does not limit this.

[0114] As shown in FIG. 1, the thickness H2 of the battery piece 111 along the height direction Z of the photovoltaic module is 100μm-250μm, which can be 100μm, 120μm, 140μm, 160μm, 180μm, 200μm, 230μm or 250μm, or other values in the above range. Figure 3 Preferably, the thickness H2 of the battery piece 111 is 130μm-180μm, in which thickness range, the thickness of the battery piece 111 is small, thereby reducing the weight of the battery piece 111 as a whole, which is conducive to the light weight of the photovoltaic module.

[0115] The present application does not limit the structure of the battery piece 111, and the types of the battery piece 111 include but are not limited to PERC cells, TOPCon cells, HJT cells, IBC cells, etc.

[0116] For a PERC cell, along its thickness direction, the PERC cell includes, in sequence, a front surface metal silver electrode, a front surface silicon nitride passivation layer, a phosphorus layer emitter, a P-type base silicon layer, a local aluminum back field, a metal aluminum back electrode, and a back passivation layer (Al2O3 / SiNx). The PERC cell uses a passivation film to passivate the back surface, replaces the full aluminum back field, enhances the internal back reflection of light on the silicon base, reduces the recombination rate of the back surface, and improves the efficiency of the cell by 0.5%-1%.

[0117] For a TOPCon cell, along its thickness direction, the TOPCon cell includes, in sequence, a metal silver electrode, a front surface silicon nitride passivation layer, a boron-doped emitter, an N-type base silicon layer, a diffusion-doped layer, an ultra-thin silicon oxide, a doped polysilicon, silicon nitride, and a metal silver electrode. The back surface of the cell is composed of an ultra-thin silicon oxide layer (1nm-2nm) and a phosphorus-doped microcrystalline amorphous mixed Si thin film, which together form a passivation contact structure. This structure can block the recombination of minority carriers, and improve the open-circuit voltage and short-circuit current of the cell. The ultra-thin oxide layer allows the tunneling of majority carriers into the polysilicon layer while blocking the recombination of minority carriers. The good passivation effect of the ultra-thin silicon oxide and the heavily doped silicon thin film causes the energy band of the silicon wafer surface to bend, thereby forming a field passivation effect. The probability of electron tunneling increases significantly, the contact resistance decreases, and the open-circuit voltage and short-circuit current of the cell are improved, thereby improving the conversion efficiency of the cell.

[0118] For the HJT cell, along the thickness direction of the HJT cell, the HJT cell comprises, in sequence, a front low-temperature silver electrode, a front conductive film, an N-type amorphous silicon film, an intrinsic amorphous silicon film, an N-type base silicon layer, an intrinsic amorphous silicon film, a P-type amorphous silicon film, a back conductive film, and a back low-temperature silver electrode.

[0119] For the IBC cell, along the thickness direction of the IBC cell, the IBC cell comprises, in sequence, a silicon nitride anti-reflection layer, an N+ front surface field, an N-type base silicon layer, a P+ emitter, an N+ back field, an aluminum oxide passivation layer, a silicon nitride anti-reflection layer, and a metal silver electrode. The IBC cell uses ion implantation technology to obtain a P region and an N region with good uniformity and precisely controllable junction depth, and the cell has no grid line shielding on the front surface, which can eliminate the shading current loss of the metal electrode, realize the maximum utilization of incident photons, and increase the short-circuit current of the conventional solar cell by about 7%; due to the back contact structure, the grid line shielding problem does not need to be considered, and the proportion of the grid line can be appropriately widened, thereby reducing the series resistance and having a high fill factor; the surface passivation and surface light trapping structure can be optimally designed, and a lower front surface recombination rate and surface reflection can be obtained.

[0120] The cell piece 111 can adopt a multi-main grid scheme, which can shorten the current conduction path, reduce internal loss, thereby improving the power of the photovoltaic module, and also can reduce the cost of the photovoltaic module; or a no-main grid scheme can be adopted, and the solder strip is used to replace the original main grid and is directly connected with the fine grid, which can greatly reduce the consumption of silver paste, thereby reducing the cost of the photovoltaic module.

[0121] The application also provides a preparation method of a photovoltaic module, as shown in Figure 9 The preparation method comprises the following steps:

[0122] Step S1: providing a photovoltaic cell group 1, the photovoltaic cell group 1 comprising a plurality of cell strings 11.

[0123] Each cell string 11 is connected in series along the length direction Y of the photovoltaic module.

[0124] Step S2: providing a front encapsulation structure and a back encapsulation structure, the front encapsulation structure comprising a front plate 2 and a front encapsulation layer 3, and the back encapsulation structure comprising a back plate 4 and a back encapsulation layer 5.

[0125] The material of the front plate 2 and the back plate 4 can be one of tempered glass, Polyethylene Terephthalate (PET), Polycarbonate (PC), etc. rigid materials or one of Polyvinyl Fluoride (PVF), Ethylene-Tetra-Fluoro-Ethylene (ETFE), Polyvinylidene Fluoride (PVDF), etc. flexible materials. The front encapsulation layer 3 and the back encapsulation layer 5 are adhesive films, and the material of the adhesive films can be one of Ethylene-Vinyl Acetate (EVA), Polyolefin Elastomer (POE), Polyvinyl Butyral (PVB), etc. materials. The front encapsulation layer 3 and the back encapsulation layer 5 can also be EPE adhesive films (EVA-POE-EVA co-extrusion structure) or EP adhesive films (EVA-EP co-extrusion structure).

[0126] Step S3: stacking the front plate 2, the front encapsulation layer 3, the photovoltaic cell group 1, the back encapsulation layer 5, and the back plate 4, and arranging the multiple cell strings 11 at intervals in the width direction X of the photovoltaic module, the interval L1 between the adjacent two cell strings 11 satisfying: 0.3mm≤L1≤1.5mm.

[0127] The stacking sequence includes two kinds: the first kind is to place the front plate 2 on the platform first, and then place the front encapsulation layer 3, the photovoltaic cell group 1, the back encapsulation layer 5, and the back plate 4 in sequence to assemble the photovoltaic module; the second kind is to place the back plate 4 on the platform first, and then place the back encapsulation layer 5, the photovoltaic cell group 1, the photovoltaic cell group 1, the front encapsulation layer 3, and the front plate 2 in sequence.

[0128] Regardless of the sequence of placement, the interval L1 between the adjacent two cell strings 11 should be 0.3mm-1.5mm, which can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, or 1.5mm, or other values within the above range, which are not limited herein. When the interval L1 between the adjacent two cell strings 11 is 0.3mm-1.5mm, the size of the cell sheet 111 in the width direction X of the photovoltaic module can be increased, which is conducive to improving the photoelectric conversion efficiency of the photovoltaic module, while avoiding the short circuit of the photovoltaic module caused by the contact between the adjacent two cell strings 11 during the lamination process, which is conducive to improving the yield of the photovoltaic module.

[0129] Step S4: laminating the front plate 2, the front encapsulation layer 3, the photovoltaic cell group 1, the back encapsulation layer 5, and the back plate 4 to form the photovoltaic module.

[0130] Laminating is to bond and fuse the components of the photovoltaic module together under certain temperature, pressure and vacuum conditions, thereby forming protection for the photovoltaic cell group 1. The laminated photovoltaic module is placed in a laminator, the air in the photovoltaic module is extracted by vacuumizing, then the front encapsulation layer 3 and the back encapsulation layer 5 are melted and solidified by heating, and the photovoltaic cell group 1, the front plate 2 and the back plate 4 are bonded together, and finally the photovoltaic module is cooled and taken out.

[0131] The preparation method of the photovoltaic module provided in the present application limits the spacing L1 between the adjacent cell strings 11 to 0.3mm-1.5mm in the laminating step, compensates the reduced spacing between the cell strings to the size of the cell sheet 111 when the width of the photovoltaic module is unchanged, and increases the size of the cell sheet 111 along the width direction X of the photovoltaic module. The blank area of the layout of the photovoltaic module can be reduced, the light receiving area of the photovoltaic cell group in unit area is increased, thereby the power generation of the photovoltaic module per unit area is increased, and the photoelectric conversion efficiency of the photovoltaic module is further increased.

[0132] In a specific embodiment, for step S3, the preparation method specifically comprises: arranging the limiting member 6 between the adjacent two groups of cell strings 11, and clamping the at least partial main body part 61 of the limiting member 6 between the adjacent two groups of cell strings 11.

[0133] In the laminating step, when the photovoltaic cell group 1 is placed, the limiting member 6 is placed between the adjacent two groups of cell strings 11, and the adjacent two groups of cell strings 11 jointly clamp the main body part 61 of the limiting member 6 along the width direction X of the photovoltaic module. After the limiting member 6 is placed, the edges of the contact part of the limiting member 6 and the cell sheet 111 can be preheated, so that the edges of the limiting member 6 are melted, and the pre-fixing of the limiting member 6 and the cell sheet 111 is realized.

[0134] When the limiting member 6 is arranged between the adjacent two groups of cell strings 11, the preparation method specifically comprises: placing the cell strings 11 and the limiting member 6 along the width direction X of the photovoltaic module in sequence.

[0135] When the cell strings 11 and the limiting member 6 are placed, it is necessary to ensure that the limiting member 6 is arranged between every two groups of cell strings 11 along the width direction X of the photovoltaic module.

[0136] As shown in Figure 1 As shown in FIG. 1, along the width direction X of the photovoltaic module, there is a certain spacing between the cell strings 11 at both ends of the photovoltaic cell group 1 and the edges of the front plate 2 and / or the back plate 4, and the front encapsulation layer 3 and the back encapsulation layer 5 after laminating can fill this position to encapsulate the side surface of the photovoltaic cell group 1. Therefore, the limiting member 6 can not be arranged on both sides of the photovoltaic cell group 1 along the width direction X of the photovoltaic module.

[0137] If the photovoltaic module adopts the first layering sequence, in the above method of arranging the cell string 11 and the limiting member 6, the cell string 11 and the limiting member 6 are placed on the side surface of the front encapsulation layer 3 away from the front plate 2; if the photovoltaic module adopts the second layering sequence, in the above method of arranging the cell string 11 and the limiting member 6, the cell string 11 and the limiting member 6 are placed on the side surface of the back encapsulation layer 5 away from the back plate 4.

[0138] In a specific embodiment, the limiting member 6 further comprises a first connecting part 62 and a second connecting part 63, which are fixedly connected to the two ends of the main body part 61 along the height direction Z of the photovoltaic module, and the cross-sectional shape of the limiting member 6 is Z-shaped. In this case, when the cell string 11 and the limiting member 6 are placed in sequence along the width direction X of the photovoltaic module, as shown in FIG. 2, the preparation method specifically comprises: Figure 10

[0139] Step A1: placing a group of cell strings 11.

[0140] Step A2: placing the limiting member 6, and connecting one of the first connecting part 62 and the second connecting part 63 to the cell string 11.

[0141] Step A3: placing another group of cell strings 11, and connecting the cell string 11 to the other one of the first connecting part 62 and the second connecting part 63, so that the two adjacent groups of cell strings 11 jointly hold the main body part 61.

[0142] At this time, the second group of cell strings 11 can limit the movement of the limiting member 6 in the width direction X of the photovoltaic module, achieving the installation and fixation of the limiting member 6.

[0143] It should be noted that along the height direction Z of the photovoltaic module, the side of the first connecting part 62 close to the front encapsulation layer 3 is the upper surface thereof, and the side away from the front encapsulation layer 3 is the lower surface thereof; along the height direction Z of the photovoltaic module, the side of the second connecting part 63 close to the back encapsulation layer 5 is the lower surface thereof, and the side away from the back encapsulation layer 5 is the upper surface thereof.

[0144] ​If the photovoltaic module adopts the first layering sequence, in the above method of arranging the battery string 11 and the limiting piece 6, a group of battery strings 11 is first placed on the surface of the front encapsulation layer 3 away from the front plate 2, then the limiting piece 6 is placed, the upper surface of the second connecting part 63 is connected to the back light surface of the group of battery strings 11, another group of battery strings 11 is placed, and the light surface of the group of battery strings 11 is connected to the lower surface of the first connecting part 62, and then the above steps are repeated to install the remaining battery strings 11 and limiting pieces 6; if the photovoltaic module adopts the second layering sequence, in the above method of arranging the battery string 11 and the limiting piece 6, a group of battery strings 11 is first placed on the surface of the back encapsulation layer 5 away from the back plate 4, then the limiting piece 6 is placed, the lower surface of the first connecting part 62 is connected to the light surface of the group of battery strings 11, another group of battery strings 11 is placed, and the back light surface of the group of battery strings 11 is connected to the upper surface of the second connecting part 63, and then the above steps are repeated to install the remaining battery strings 11 and limiting pieces 6.

[0145] In another specific embodiment, the limiting piece 6 further comprises a first connecting part 62 and a second connecting part 63, which are fixedly connected to the two ends of the main body part 61 in the height direction Z of the photovoltaic module, and the cross-sectional shape of the limiting piece 6 is C-shaped. In this case, when the limiting piece 6 is arranged between the two adjacent groups of battery strings 11, as shown in FIG. 6B, the preparation method specifically comprises the following steps. Figure 11

[0146] Step B1: the lower surface of the first connecting part 62 and the upper surface of the second connecting part 63 are respectively connected to the light surface and the back light surface of the same group of battery strings 11, so that the limiting piece 6 is clamped on the battery string 11 to form a battery string assembly.

[0147] The limiting piece 6 is first clamped on the battery string 11, which can realize stable connection of the limiting piece 6 and the battery string 11, improve the installation stability of the limiting piece 6, avoid displacement of the limiting piece 6, and be beneficial to improving the isolation effect of the limiting piece 6 on the two adjacent groups of battery strings 11.

[0148] Step B2: a plurality of battery string assemblies are sequentially placed in the width direction X of the photovoltaic module, so that the two adjacent groups of battery strings 11 jointly hold the main body part 61.

[0149] The limiting piece 6 and the battery string 11 are placed in the form of a battery string assembly, which can set the positional relationship between the limiting piece 6 and the battery string 11 in advance, compared with the sequential placement of the two, and there is no need to adjust the position of the limiting piece 6 during layering, thereby improving the preparation efficiency of the photovoltaic module.

[0150] ​If the photovoltaic module adopts the first layering sequence, in the above method, the placement position of the battery string assembly is the side surface of the front encapsulation layer 3 away from the front plate 2; if the photovoltaic module adopts the second layering sequence, in the above method, the placement position of the battery string assembly is the side surface of the back encapsulation layer 5 away from the back plate 4. In another specific embodiment, the limiting member 6 is in an integrated structure with the front encapsulation layer 3, and at least one limiting member 6 and the front encapsulation layer 3 enclose the accommodation space, and when the limiting member 6 is arranged between the adjacent two groups of battery strings 11, the preparation method specifically comprises: accommodating the battery string 11 in the accommodation space, so that the adjacent two groups of battery strings 11 jointly clamp the main body part 61.

[0151] If the photovoltaic module adopts the first layering sequence, in the above method, the battery string 11 is placed on the side surface of the front encapsulation layer 3 provided with the limiting member 6, and the battery string 11 should be accommodated in the accommodation space; if the photovoltaic module adopts the second layering sequence, in the above method, first, a plurality of groups of battery strings 11 are arranged at intervals on the side surface of the back encapsulation layer 5 away from the back plate 4, and then the side surface of the front encapsulation layer 3 provided with the limiting member 6 is laid towards the photovoltaic cell group 1, and in this process, attention should be paid to aligning the spacing of the limiting member 6 and the adjacent two groups of battery strings 11 along the height direction Z of the photovoltaic module, so that the battery string 11 can be accommodated in the accommodation space.

[0152] Alternatively, the limiting member 6 is in an integrated structure with the back encapsulation layer 5, and at least one limiting member 6 and the back encapsulation layer 5 enclose the accommodation space, and when the limiting member 6 is arranged between the adjacent two groups of battery strings 11, the preparation method specifically comprises: accommodating the battery string 11 in the accommodation space, so that the adjacent two groups of battery strings 11 jointly clamp the main body part 61.

[0153] If the photovoltaic module adopts the second layering sequence, in the above method, first, a plurality of groups of battery strings 11 are arranged at intervals on the side surface of the front encapsulation layer 3 away from the front plate 2, and then the side surface of the back encapsulation layer 5 provided with the limiting member 6 is laid towards the photovoltaic cell group 1, and in this process, attention should be paid to aligning the spacing of the limiting member 6 and the adjacent two groups of battery strings 11 along the height direction Z of the photovoltaic module, so that the battery string 11 can be accommodated in the accommodation space; if the photovoltaic module adopts the second layering sequence, in the above method, the battery string 11 is placed on the side surface of the back encapsulation layer 5 provided with the limiting member 6, and the battery string 11 should be accommodated in the accommodation space.

[0154] In a specific embodiment, before the spacer 6 is arranged between the two adjacent groups of battery strings 11, the preparation method further comprises: arranging a positioning tape 7 on the two adjacent groups of battery strings 11, and the two ends of the positioning tape 7 are respectively adhered to the two adjacent groups of battery strings 11 along the width direction X of the photovoltaic module; or after the spacer 6 is arranged between the two adjacent groups of battery strings 11, the preparation method further comprises: arranging a positioning tape 7 on the two adjacent groups of battery strings 11, and the two ends of the positioning tape 7 are respectively adhered to the two adjacent groups of battery strings 11 along the width direction X of the photovoltaic module.

[0155] If the spacer 6 has only the main body 61, but does not have the first connecting part 62 and the second connecting part 63, as shown in FIG. 6, during the stacking process, the two groups of battery strings 11 are placed first, then the positioning tape 7 is adhered between the two groups of battery strings, and then the spacer 6 is inserted between the two groups of battery strings 11 which have been fixed in position by the positioning tape 7, and then another battery string 11 is placed, so that one of the two groups of battery strings 11 arranged just now is connected with the battery string 11 through the positioning tape 7, and then the spacer 6 is inserted between them. Figure 3

[0156] If the cross section of the spacer 6 is C-shaped, Z-shaped or H-shaped, or the spacer 6 is an integral structure with the front encapsulation layer 3 and / or the back encapsulation layer 5, then the positioning tape 7 can be adhered after the battery string 11 and the spacer 6 are placed, and preferably, the two groups of battery strings 11 can be connected with the spacer 6 first, and then the positioning tape 7 is adhered on the two groups of battery strings 11, and then the remaining battery strings 11 are placed and connected in this order, that is, after the two groups of battery strings 11 are placed and the spacer 6 is arranged, the positioning tape 7 is adhered.

[0157] According to the stacking sequence of the photovoltaic module, the positioning tape 7 can be selectively adhered on the light-receiving surface or the back surface of the battery piece 111, for example, when the spacer 6 has the structure shown in FIG. 6, and the first stacking sequence is adopted, the battery piece 111 is placed on the front encapsulation layer 3 first, so that the light-receiving surface is first attached to the front encapsulation layer 3, in this case, the positioning tape 7 can be adhered on the back surface of the battery piece 111. Figure 3 Figure 3 When the spacer 6 has the structure shown in FIG. 7, and the second stacking sequence is adopted, the battery piece 111 is placed on the back encapsulation layer 5 first, so that the back surface is first attached to the back encapsulation layer 5, in this case, the positioning tape 7 can be adhered on the light-receiving surface of the battery piece 111. When the spacer 6 has other structures, the positioning position of the positioning tape 7 is the same.

[0158] In order to reduce the influence of the positioning tape 7 on the power of the photovoltaic module, it is preferred to be adhered on the back surface of the battery piece 111.

[0159] ​​It should be noted that the data involved in the above embodiments can have an error value of 5% to 10%, which does not affect the technical effects of the present application.

[0160] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Those skilled in the art can make various modifications and changes to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A photovoltaic module, characterized in that: The photovoltaic module comprises: A photovoltaic cell group (1), comprising a plurality of cell strings (11) arranged at intervals along the width direction of the photovoltaic module; A front encapsulation structure is arranged on the light-facing surface of the photovoltaic cell group (1), the front encapsulation structure comprising a front plate (2) and a front encapsulation layer (3); A backside encapsulation structure is provided on the backlight side of the photovoltaic cell group (1), the backside encapsulation structure comprising a backsheet (4) and a backside encapsulation layer (5), the backsheet (4) and the front sheet (2) jointly clamping the front side encapsulation layer (3), the photovoltaic cell group (1) and the backside encapsulation layer (5); A limiting member (6) is located between two adjacent groups of battery strings (11), the limiting member (6) comprising a main body (61), a first connecting portion (62) and a second connecting portion (63), wherein the first connecting portion (62) and the second connecting portion (63) are fixedly connected to two ends of the main body (61) along the height direction of the photovoltaic module, and at least a portion of the main body (61) is clamped between the two adjacent groups of battery strings (11); Wherein, along the width direction of the photovoltaic module, the spacing L1 between two adjacent groups of the battery strings (11) satisfies: 0.3mm≤L1≤1.5mm.

2. The photovoltaic module according to claim 1, characterized in that The upper surface of the first connecting portion (62) is used to connect to the front encapsulation layer (3), and the lower surface of the second connecting portion (63) is used to connect to the back encapsulation layer (5).

3. The photovoltaic module according to claim 1, characterized in that Along the height direction of the photovoltaic assembly, the height H1 of the limiting member (6) satisfies: 0.5 mm ≤ H1 ≤ 3 mm.

4. The photovoltaic module according to claim 1, characterized in that The material of the limiting member (6) is an insulating material; The limiting member (6) is made of one of adhesive film, transparent glass, cured insulating adhesive, transparent plastic plate, and transparent rubber.

5. The photovoltaic module according to claim 1, characterized in that The limiting member (6) and the front packaging layer (3) are an integrated structure, at least one limiting member (6) and the front packaging layer (3) enclose a receiving space, and the battery string (11) is located in the receiving space; And / or, the limiting member (6) and the back packaging layer (5) are an integrated structure, at least one of the limiting members (6) and the back packaging layer (5) enclose a receiving space, and the battery string (11) is located in the receiving space.

6. The photovoltaic module according to claim 1, characterized in that The cross-sectional shape of the limiting member (6) is Z-shaped; The lower surface of the first connecting portion (62) is connected to the light-facing surface of the battery string (11), and the upper surface of the second connecting portion (63) is connected to the backlight surface of another adjacent group of battery strings (11).

7. The photovoltaic module according to claim 1, characterized in that The cross-sectional shape of the limiting member (6) is C-shaped; The lower surface of the first connecting portion (62) and the upper surface of the second connecting portion (63) are respectively connected to the light-facing surface and the backlight surface of the same battery string (11).

8. The photovoltaic module according to any one of claims 1 to 7, characterized in that: A plurality of the limiting members (6) are provided between two adjacent groups of the battery strings (11), and the plurality of the limiting members (6) are spaced apart along the length direction of the photovoltaic assembly.

9. The photovoltaic module according to claim 1, characterized in that: The battery string (11) comprises a plurality of battery cells (111) arranged along the length direction of the photovoltaic module, wherein the battery cells (111) have a first size D1 along the width direction of the photovoltaic module, and a second size D2 along the length direction of the photovoltaic module; The battery cell (111) is a two-piece cell, and the values ​​of D1:D2 satisfy: 2<D1:D2≤2.02; Alternatively, the battery cell (111) is divided into three pieces, and the values ​​of D1:D2 satisfy: 3.01≤D1:D2≤3.03; Alternatively, the battery cell (111) is divided into four pieces, and the values ​​of D1:D2 satisfy: 4.01≤D1:D2≤4.

04.

10. A method for preparing a photovoltaic module, characterized in that: The photovoltaic assembly comprises a photovoltaic cell group (1), a position-limiting member (6), a front encapsulation structure, and a back encapsulation structure; the position-limiting member (6) comprises a main body (61), a first connecting portion (62), and a second connecting portion (63); along the height direction of the photovoltaic assembly, the first connecting portion (62) and the second connecting portion (63) are fixedly connected to both ends of the main body (61); The preparation method comprises the following steps: The photovoltaic cell group (1), the limiting member (6), the front encapsulation structure and the back encapsulation structure are provided, wherein the photovoltaic cell group (1) comprises a plurality of cell strings (11), the front encapsulation structure comprises a front plate (2) and a front encapsulation layer (3), and the back encapsulation structure comprises a back plate (4) and a back encapsulation layer (5); The front plate (2), the front encapsulation layer (3), the photovoltaic cell group (1), the limiting member (6), the back encapsulation layer (5) and the back plate (4) are stacked so that a plurality of groups of cell strings (11) are arranged at intervals in the width direction of the photovoltaic module and the spacing L1 between two adjacent cell strings (11) satisfies: 0.3 mm ≤ L1 ≤ 1.5 mm, and the limiting member (6) is provided between two adjacent groups of cell strings (11) so that at least a portion of the main body (61) is clamped between the two adjacent groups of cell strings (11); The front plate (2), the front encapsulation layer (3), the photovoltaic cell group (1), the position-limiting member (6), the back encapsulation layer (5) and the back plate (4) are laminated to form the photovoltaic module.

11. The method for preparing a photovoltaic module according to claim 10, wherein: When the limiting member (6) is provided between two adjacent groups of battery strings (11), the preparation method specifically comprises: The battery string (11) and the limiting member (6) are placed in sequence along the width direction of the photovoltaic assembly.

12. The method for preparing a photovoltaic module according to claim 11, characterized in that: The cross-sectional shape of the limiting member (6) is Z-shaped. When the battery string (11) and the limiting member (6) are placed in sequence along the width direction of the photovoltaic module, the preparation method specifically comprises: placing a group of battery strings (11); placing the limiting member (6) and connecting one of the first connecting portion (62) and the second connecting portion (63) to the battery string (11); Another group of battery strings (11) is placed, and the battery strings (11) are connected to the other of the first connecting portion (62) and the second connecting portion (63), so that the two adjacent groups of battery strings (11) jointly clamp the main body (61).

13. The method for preparing a photovoltaic module according to claim 10, wherein: The cross-sectional shape of the limiting member (6) is C-shaped. When the limiting member (6) is provided between two adjacent groups of battery strings (11), the preparation method specifically comprises: The lower surface of the first connecting portion (62) and the upper surface of the second connecting portion (63) are respectively connected to the light-facing surface and the backlight surface of the same group of battery strings (11), so that the limiting member (6) is clamped on the battery string (11) to form a battery string assembly; A plurality of the battery string assemblies are placed in sequence along the width direction of the photovoltaic assembly so that two adjacent groups of battery strings (11) jointly clamp the main body (61).

14. The method for preparing a photovoltaic module according to claim 10, wherein: The limiting member (6) and the front packaging layer (3) are an integrated structure, at least one limiting member (6) and the front packaging layer (3) enclose a receiving space, and when a limiting member (6) is provided between two adjacent groups of battery strings (11), the preparation method specifically comprises: The battery strings (11) are accommodated in the accommodation space so that two adjacent battery strings (11) jointly clamp the main body (61); And / or, the limiting member (6) and the back packaging layer (5) are an integrated structure, at least one of the limiting members (6) and the back packaging layer (5) enclose a receiving space, and when a limiting member (6) is provided between two adjacent groups of battery strings (11), the preparation method specifically includes: The battery string (11) is accommodated in the accommodation space so that two adjacent groups of battery strings (11) jointly clamp the main body (61).

15. The method for preparing a photovoltaic module according to claim 10, wherein: Before arranging the limiting member (6) between two adjacent groups of battery strings (11), the preparation method further comprises: Positioning tapes (7) are provided on two adjacent groups of battery strings (11), and along the width direction (X) of the photovoltaic module, two ends of the positioning tapes (7) are respectively bonded to the two adjacent groups of battery strings (11); Alternatively, after providing a limiting member (6) between two adjacent groups of battery strings (11), the preparation method further comprises: Positioning tapes (7) are provided on two adjacent groups of battery strings (11), and along the width direction (X) of the photovoltaic module, two ends of the positioning tapes (7) are respectively adhered to the two adjacent groups of battery strings (11).

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