Back contact battery string, series welding equipment thereof and photovoltaic module

Abstract

The utility model relates to the photovoltaic field, and discloses a back contact cell string and a series welding device thereof, and a photovoltaic assembly. The back contact battery string comprises a plurality of battery pieces, a welding rod and a skin film. And the skin membrane comprises closed areas and opening areas which are alternately distributed at intervals. The area where the skin film is attached to the welding rod is a closed area. The photovoltaic module comprises the back contact cell string. The series welding equipment is used for welding the back contact battery string and comprises a rack, a conveying mechanism, a substrate platform and a heating assembly. A plurality of slotted holes are formed in the conveying belt; the skin film is laid on the conveying belt, and corresponding groove holes are formed below the closed area and the hole opening area of the skin film. A plurality of air suction holes corresponding to the groove holes are formed in the base plate platform. According to the utility model, the traditional skin film is replaced by the skin film with the holes in the specific area, the problems caused by the use of pressing blocks are reduced by adsorption fixation and canceling the positioning of the pressing blocks, and the product quality and the production efficiency are improved. And meanwhile, the bonding force in the assembly can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to photovoltaic field especially a kind of back contact cell string and its string welding equipment, photovoltaic module. BACKGROUND

[0002] The current string welding production equipment of back contact solar cell is generally divided into: infrared hot welding, film string welding, and both of these two string welding schemes need to use press to position cell sheet and welding rod. Among them, the existing infrared hot welding has obvious shortcomings, that is, the cell sheet is severely warped after welding, and although film string welding can solve the warping problem, it has the problem that the TC thermal cycle test experiment and DH damp heat experiment of module are more prone to failure.

[0003] For example: patent "CN 220553452 U" discloses a no main grid back contact cell string, photovoltaic module and string preparation equipment, which provides a no main grid back contact cell string. Only the positive metal grid line and the negative metal grid line on the back surface of the cell sheet are staggered in the cell sheet that constitutes the cell string, the welding rod is staggered and connected with the positive metal grid line and the negative metal grid line, and the welding rod is fixed on the back surface of the cell sheet by the adhesive film, which simplifies the above-mentioned series connection process of the no main grid cell sheet. (referred to as back contact cell film scheme).

[0004] Patent "CN220895518U" discloses a cell string preparation equipment, which further describes how to perform back contact cell string welding according to patent "CN220553452U".

[0005] Patent "CN 221262412 U" discloses a press and adhesive film composite conveying device and cell string production equipment, which mainly aims at improving the problems of the press in the prior art scheme of patent "CN220895518U". The technical scheme can solve the problem that the position of the press gripper for grabbing the press is always changing after being transported for many times, the relative position of the press and the adhesive film also changes, and the film grabbing assembly of the string laying gripper needs to pass through the hole of the press to grab the adhesive film, thereby causing the string laying gripper to adjust the position and then grab, which causes the simultaneous grabbing precision of the string laying gripper to decrease and also affects the grabbing speed.

[0006] Therefore, although the existing string welding technology can fix the welding rod and the cell sheet well, it still has the following problems:

[0007] I. The existing back contact solar cell string welding equipment needs to use a press to pre-position the photovoltaic welding rod, which can easily cause scratches on the surface of the cell sheet, reduce the efficiency of the photovoltaic cell string welding, and make the overall structure of the equipment more complex due to the presence of the press, which increases the cost of the equipment and greatly increases the failure rate of the equipment.

[0008] Two, the existing back contact battery film scheme adopts the conventional skin film for packaging, although the welding rod and the battery piece can be fixed better, but the skin film also produces a certain gap with the adhesive film of the adhesive back plate, thereby causing the adhesion ability of the back of the battery and the back plate to decline, which has a great hidden danger to the reliability of the module. Especially prone to cause TC thermal cycle test experiment, DH damp heat experiment failure. Practical new type content

[0009] The utility model discloses a back contact battery string and its string welding equipment and photovoltaic module, and the skin film of specific area opening replaces the traditional skin film, reduces the battery surface scratch, string welding efficiency low, equipment structure complex and other problems caused by the use of pressure block, and the skin film of opening can also improve the adhesion of the inside of the module, improve the TC thermal cycle test experiment, DH damp heat experiment failure of the module.

[0010] To achieve the above object, the utility model adopts the following technical scheme:

[0011] The utility model discloses a back contact battery string, it includes a plurality of battery piece, welding rod and skin film. The welding rod and the main grid area of adjacent two battery pieces are pasted. Skin film is set below welding rod, is used for fixing welding rod on battery piece. The skin film includes the closed area and the opening area of the alternate interval distribution on it;The area of skin film and the welding rod pasting is the closed area.

[0012] Further, a plurality of small pores or large round holes or slot holes or other irregular gaps are arranged on the opening area.

[0013] Further, the skin film is EVA adhesive film with a weight of 95g / m2 to 105g / m2 after irradiation treatment.

[0014] The utility model discloses a back contact battery photovoltaic module, which comprises photovoltaic front plates, first adhesive films, battery strings, second adhesive films and photovoltaic back plates which are laminated in sequence.

[0015] Further, the photovoltaic front plates are glass or ETFE, the first adhesive films and the second adhesive films are one of EVA, POE and EPE, and the photovoltaic back plates are glass or KPF.

[0016] The utility model discloses a string welding equipment for welding the above-mentioned back contact battery string, which comprises a rack, a conveying mechanism, a base plate platform and a heating assembly.

[0017] The conveying mechanism comprises a conveying wheel and a conveying belt; the conveying belt comprises an upper conveying belt and a lower conveying belt; the conveying mechanism is arranged on a rack, the upper conveying belt is arranged above an operating table of the rack, and the lower conveying belt is arranged below the operating table of the rack; a plurality of slots are arranged on the conveying belt; a skin film is arranged on the conveying belt, and the skin film is provided with a sealed area and a perforated area, and the sealed area and the perforated area are both provided with the slots.

[0018] The substrate platform comprises a plurality of substrates, the substrates are arranged on the conveying mechanism and are arranged on the inner side of the conveying belt; a plurality of suction holes are arranged on each substrate platform, and the suction holes correspond to the slots; and a heating assembly is arranged in the substrate.

[0019] Further, the substrate arranged on the upper conveying belt is a first substrate, the substrate arranged on the lower conveying belt is a second substrate, the suction holes of the first substrate are arranged in regions corresponding to the sealed area and the perforated area of the skin film, the suction holes of the second substrate are arranged in a region corresponding to the sealed area of the skin film, and the suction holes of each substrate are arranged in a separate circuit.

[0020] Further, the heating assembly comprises a heater and a temperature sensor.

[0021] Further, a welding rod conveying and cutting mechanism is arranged above the upper conveying belt, a skin film conveying and cutting mechanism is arranged below the lower conveying belt, and a cooling device is further arranged at the end of the upper conveying belt.

[0022] The skin film with specific region perforation of the utility model replaces the traditional skin film, the problems of battery surface scratch, low series welding efficiency and complex equipment structure caused by the use of pressing block are solved by adsorption fixation and cancellation of pressing block positioning, and the skin film with specific region perforation can also improve the adhesion of the internal components and improve the problems of TC thermal cycle test experiment and DH damp heat experiment failure.

[0023] The skin film with specific region perforation of the utility model replaces the traditional skin film, the problems of battery surface scratch, low series welding efficiency and complex equipment structure caused by the use of pressing block are solved by adsorption fixation and cancellation of pressing block positioning, and the skin film with specific region perforation can also improve the adhesion of the internal components and improve the problems of TC thermal cycle test experiment and DH damp heat experiment failure. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the utility model, and therefore should not be regarded as a limitation to the scope, and for those skilled in the art, other related drawings can also be obtained according to these drawings without creative labor.

[0025] Figure 1 It is a structural schematic diagram of the battery string of embodiment one.

[0026] Figure 2 It is Figure 1 It is a local enlarged view of A in the figure.

[0027] Figure 3 is a partial plane structure schematic diagram of the skin film of the utility model.

[0028] Figure 4 is a plane structure schematic diagram of the welding rod setting on the skin film.

[0029] Figure 5 is a structure schematic diagram of the welding equipment of example three.

[0030] Figure 6 is a partial plane structure schematic diagram of the second base plate in the welding equipment.

[0031] Figure 7 is a partial plane structure schematic diagram of the conveying belt in the welding equipment.

[0032] Figure 8 is a position relation diagram between the second base plate and the conveying belt in the welding equipment.

[0033] Figure 9 is a position relation diagram between the second base plate, the conveying belt and the skin film in the welding equipment.

[0034] Figure 10 is a partial plane structure schematic diagram of the first base plate in the welding equipment.

[0035] Figure 11 is a position relation diagram between the first base plate, the conveying belt and the skin film in the welding equipment.

[0036] Main component symbol explanation:

[0037] 1, battery piece;

[0038] 2, welding rod;

[0039] 3, skin film, 31, closed area, 32, open hole area;

[0040] 4, skin film conveying cutting mechanism;

[0041] 5, conveying belt, 51, upper section conveying belt, 52, lower section conveying belt, 53, slot hole;

[0042] 6, base plate platform, 61, first base plate, 62, second base plate, 63, air suction hole. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely in conjunction with the drawings of the specification. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0044] In the present application, the orientation words such as "up, down, left, right" are generally understood in connection with the orientation shown in the drawings and the actual application, unless otherwise stated.

[0045] In addition, the terms "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as "first" and "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more than two, unless otherwise specifically limited.

[0046] In the present application, unless otherwise specifically stated and limited, the first feature "on" or "under" the second feature can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0047] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The ranges or values should be construed to include values approximately around the ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. Among them, the terms "optional" and "optional" mean that it can be included or not included (or can be included or not included).

[0048] As Figures 1 to 4As shown, the utility model discloses a back contact battery string, it includes a plurality of battery piece 1, welding rod 2 and skin film 3. Welding rod 2 and the main grid area of two adjacent battery piece 1 are in conformity. Skin film 3 is set below welding rod 2, is used for fixing welding rod 2 on battery piece 1. Skin film 3 includes the closed area 31 and the open hole area 32 of alternate interval distribution. When string welding, the closed area 31 is as skin film 3 adsorption fixed area, is used for skin film 3 adsorption fixed on the conveyer belt. The open hole area 32 is as battery piece 1 adsorption fixed area, can pass through open hole area 32 and be adsorbed fixed battery piece 1 on the conveyer belt.

[0049] This embodiment replaces the traditional skin film by the skin film 3 of specific area open hole, by adsorbing and fixing skin film 3 and battery piece 1, cancels the pressing block positioning, reduces the battery surface scratch, string welding efficiency low, equipment structure complex and other problems caused by using pressing block.

[0050] Wherein, the area of skin film 3 and welding rod 2 is the closed area 31. Can avoid the melting of adhesive film and seep into photovoltaic welding rod 2 and back contact battery.

[0051] Wherein, a plurality of small air holes or large round holes or slot holes 53 or other irregular gaps are arranged on the open hole area 32. The main purpose is that battery piece 1 can be adsorbed on the air hole film and accurately positioned with photovoltaic welding rod, and the air hole film is bonded on the back of the battery by the heating system of the base plate platform 6 to fix the photovoltaic welding rod.

[0052] Specifically, the skin film 3 is an EVA adhesive film with a grammage of 95g / m2 to 105g / m2 after irradiation treatment.

[0053] Example two:

[0054] The utility model discloses still a kind of back contact battery photovoltaic module, including photovoltaic front plate, first adhesive film, battery string, second adhesive film, photovoltaic back plate in turn laminated. Wherein, battery string is the back contact battery string of example one. Photovoltaic front plate is bonded with the front of battery string by first adhesive film, and photovoltaic back plate is bonded with the back of skin film 3 and battery string respectively through the open hole area 32 of second adhesive film seeping through skin film 3.

[0055] When the conventional skin film 3 battery string is laminated, the skin film 3 is made into the material of the isolation adhesive film to avoid the penetration of the adhesive film into the back contact battery between the photovoltaic solder 2 after the melting of the adhesive film, so the relationship between them is that the back plate is bonded on the adhesive film, the adhesive film is bonded on the skin film 3, and the skin film 3 is bonded on the back of the battery, because a layer of skin film 3 is separated, it is easy to cause the adhesion between the back plate and the back of the battery to be reduced. In the lamination of the embodiment, the adhesive film can penetrate the opening area 32 of the skin film 3 and form a more firm adhesion with the back of the battery piece 1, so as to improve the adhesion between the back plate and the battery piece 1, and further improve the reliability of the photovoltaic module. The failure problem of the TC thermal cycle test experiment and the DH damp heat experiment of the module is improved.

[0056] The photovoltaic front plate is glass or ETFE, the first adhesive film and the second adhesive film are one of EVA, POE and EPE, and the photovoltaic back plate is glass or KPF.

[0057] Embodiment three:

[0058] As shown in Figures 1 to 11 The utility model discloses still a kind of string welding equipment for welding above-mentioned back contact battery string, it includes rack, conveying mechanism, base plate platform 6, heating assembly, skin film 3 delivery cutting mechanism 4, solder delivery cutting mechanism, cooling device. Wherein, conveying mechanism is fixed on rack, for conveying skin film 3, solder and battery piece 1. Base plate platform 6 is arranged in conveying mechanism inside, for adsorbing and fixing skin film 3 and battery piece 1. Heating assembly is arranged on base plate platform 6, for preheating skin film 3 and subsequent heating skin film 3, and solder 2 is welded on battery piece 1. The skin film 3 of roll is arranged on skin film 3 delivery cutting mechanism 4, skin film 3 delivery cutting mechanism 4 is arranged below conveying mechanism, after cutting skin film 3 according to set length, it is adsorbed and fixed on conveying mechanism by base plate platform 6, and preheating is carried out. Solder delivery cutting mechanism is arranged above conveying mechanism, solder 2 is placed on skin film 3 after cutting according to set length by solder delivery cutting mechanism. Cooling device is arranged at the rear end of conveying mechanism, for cooling battery string after welding, facilitate to take material.

[0059] Specifically, as shown in Figure 5 Conveying mechanism includes conveying wheel and conveying belt 5. Conveying belt 5 includes upper section conveying belt 51 and lower section conveying belt 52. Upper section conveying belt 51 is located above the operating table of rack, and lower section conveying belt 52 is located below the operating table of rack. As shown in Figure 7 A plurality of grooves 53 are arranged on conveying belt 5. As shown in Figure 9 Skin film 3 is laid on conveying belt, and corresponding grooves 53 are arranged below sealed area 31 and opening area 32 of skin film 3.

[0060] The substrate platform 6 comprises several substrate blocks, which are arranged on the conveying mechanism and located on the inner side of the conveying belt. Each substrate platform 6 is provided with several suction holes 63.

[0061] Specifically, the substrate arranged by the upper conveying belt 51 is the first substrate 61, and the substrate arranged by the lower conveying belt 52 is the second substrate 62. As shown in the figure, the suction holes 63 of the first substrate 61 are arranged in the area corresponding to the closed area 31 and the opening area 32 of the skin film 3, for adsorbing and fixing the skin film 3 and the battery piece 1. As shown in the figure, Figures 6 to 9 Figure 10 , 11 As shown in the figure, the suction holes 63 of the second substrate 62 are arranged in the area corresponding to the closed area 31 of the skin film 3, for adsorbing and fixing the skin film 3.

[0062] In order to arrange the suction holes 63 of each substrate as a separate circuit, the airtightness during suction is ensured.

[0063] Specifically, the heating assembly comprises a heater and a temperature sensor. The heater and the temperature sensor form a thermocouple heating platform, and the temperature can be set through the control panel of the string welding device.

[0064] The manufacturing method of the above string welding device comprises the following steps:

[0065] S1, placing the skin film 3 and preheating: placing the segmented skin film 3 on the conveying belt 5, and adsorbing and preheating the skin film 3 on the conveying belt through the substrate platform 6, wherein the preheating temperature is 80-100℃. Preheating the skin film 3 first can make the surface of the skin film 3 have certain adhesion, so that the photovoltaic solder will not run on the skin film 3 after laying, and the skin film 3 will not deform after further shrinking after preheating.

[0066] S2, placing the solder 2 and laying the battery piece 1: the skin film 3 is conveyed to the operation table following the conveying belt 5, the segmented solder 2 is placed on the skin film 3, and several battery pieces 1 are placed on the solder 2, and the battery piece 1 is adsorbed and fixed on the conveying belt 5 through the substrate platform 6, wherein the main grid area on the back of the battery piece 1 is attached to the solder 2;

[0067] S3, welding the solder 2: heating the skin film 3, and adhering and fixing the laid solder 2 and the back of the battery through the skin film 3.

[0068] S4, cooling and taking out: cooling the fixed product, and taking out the completed battery string.

[0069] ​The prior art, if the cell back of the back contact solar cell is upwardly welded, the laying sequence is the same as the embodiment, but two problems will occur: one is that if the pressing block is not used to press the cell piece 1, the cell piece 1 will run and be misaligned with the movement of the conveying belt; two is that the skin film 3 will shrink during the welding process, resulting in misalignment of the position of the photovoltaic welding rod 2 and the cell back main grid. If the cell back of the back contact solar cell is downwardly welded, the cell piece 1 is laid first, and then the photovoltaic welding rod 2 is laid, at this time, the photovoltaic welding rod 2 needs to be pressed by a pressing block to prevent running, and a pressing block also needs to be introduced. The embodiment realizes that the skin film 3 can be adsorbed and fixed, the photovoltaic welding rod 2 can be fixed on the skin film 3, and the cell piece 1 can be further adsorbed and fixed by pre-setting the air suction structure of the skin film 3, the substrate platform 6 and the conveying belt, and then the cell piece 1 is welded in series by heating through the substrate platform 6, so that the use of the series welding pressing block can be avoided, the use of the mechanical hand of the equipment and the arrangement of the pressing block conveying platform can be reduced, and the equipment cost can be greatly reduced.

[0070] In summary, the skin film with specific area openings of the utility model replaces the traditional skin film, adsorbs and fixes, cancels the pressing block positioning, reduces the problems caused by the use of the pressing block, improves the product quality and production efficiency. The skin film with openings can also improve the adhesion of the internal components, improve the failure problems of the TC thermal cycle test experiment and DH damp heat experiment of the components.

[0071] The above describes the preferred embodiments of the utility model, but the utility model is not limited to this. Within the technical concept range of the utility model, the technical scheme of the utility model can be variously modified, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the disclosed content of the utility model, and all belong to the protection range of the utility model.

Claims

1. A back contact cell string, characterized by: The application relates to a back contact battery string, which comprises a plurality of battery pieces, a welding strip and a skin film; the welding strip is attached to the main grid area of two adjacent battery pieces; the skin film is arranged below the welding strip and is used for fixing the welding strip on the battery piece; the skin film comprises closed areas and open hole areas which are alternately and spacedly arranged; the area, where the skin film is attached to the welding strip, is a closed area.

2. The back contact cell string of claim 1, wherein: A plurality of small air holes, large round holes or slot holes are arranged on the open hole area.

3. The back contact cell string of claim 1, wherein: The skin film is an EVA adhesive film with a weight of 95-105 g / m2 after irradiation treatment.

4. A back contact cell photovoltaic module, comprising a photovoltaic front sheet, a first adhesive film, a cell string, a second adhesive film, a photovoltaic back sheet laminated in sequence, characterized in that: The battery string is the back contact battery string according to any one of claims 1-3; the photovoltaic front plate is bonded to the front surface of the battery string through a first adhesive film, and the photovoltaic back plate is bonded to the skin film and the back surface of the battery string through a second adhesive film which penetrates the open hole area of the skin film.

5. The back contact solar cell photovoltaic module of claim 4, wherein: The photovoltaic front plate is glass or ETFE, the first adhesive film and the second adhesive film are one of EVA, POE and EPE, and the photovoltaic back plate is glass or KPF.

6. String welding apparatus for welding the back contact string of any one of claims 1 to 3, characterized in that: The application relates to a machine frame, a conveying mechanism, a substrate platform and a heating assembly. The conveying mechanism comprises conveying wheels and a conveying belt; the conveying belt comprises an upper conveying belt and a lower conveying belt; the conveying mechanism is arranged on the machine frame, the upper conveying belt is arranged above the operation table of the machine frame, and the lower conveying belt is arranged below the operation table of the machine frame; a plurality of slot holes are arranged on the conveying belt; the skin film is arranged on the conveying belt, and the closed area and the open hole area of the skin film are below the corresponding slot holes. The substrate platform comprises a plurality of substrates which are arranged on the conveying mechanism and are located on the inner side of the conveying belt; a plurality of air suction holes are arranged on each substrate platform, the air suction holes are corresponding to the slot holes, and the heating assembly is arranged in the substrate.

7. The stringer apparatus of claim 6, wherein: The substrate arranged on the upper conveying belt is a first substrate, the substrate arranged on the lower conveying belt is a second substrate, the air suction holes of the first substrate are arranged in the area corresponding to the closed area and the open hole area of the skin film, the air suction holes of the second substrate are arranged in the area corresponding to the closed area of the skin film, and the air suction holes of each substrate are arranged in a single loop.

8. The stringer apparatus of claim 6, wherein: The heating assembly comprises a heater and a temperature sensor.

9. The stringer welding apparatus of claim 6, wherein: A welding strip conveying and cutting mechanism is arranged above the upper conveying belt, a skin film conveying and cutting mechanism is arranged below the lower conveying belt, and a cooling device is further arranged at the end of the upper conveying belt.

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