Photovoltaic module

Abstract

The utility model relates to photovoltaic power generation technical field discloses photovoltaic module, from below to above includes electric core, first sealing rubber sheet, second sealing rubber sheet, water -resistant membrane and backboard in proper order, second sealing rubber sheet is equipped with the first through -hole along the up and down direction, and backboard is equipped with the second through -hole along the up and down direction correspondingly, and second through -hole is equipped with second plugging piece, photovoltaic module still includes drainage bar, and drainage bar is electrically connected with electric core, and drainage bar is at least partially clamped between first sealing rubber sheet and second sealing rubber sheet, and drainage bar passes first through -hole in proper order, bypasses or passes water -resistant membrane, and passes second through -hole. The utility model adopts the structure of first sealing rubber sheet, second sealing rubber sheet cooperation water -resistant membrane realizes the barrier to water vapor, and water -resistant membrane is arranged between backplate and second sealing rubber sheet, and second plugging piece can be sealed second through -hole after laminating is completed, and the barrier effect to water vapor is improved significantly, thereby the service life of photovoltaic module is improved.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic power generation technology, specifically to photovoltaic modules. Background Technology

[0002] Perovskite photovoltaic modules are extremely sensitive to moisture, requiring encapsulation design to prevent moisture from penetrating into their interior. The backsheet of perovskite photovoltaic modules needs openings to allow current-carrying strips to draw current out from the inside of the module.

[0003] Currently, perovskite photovoltaic modules typically use butyl rubber to seal the backsheet holes to block moisture. The current guides are usually vertically installed within the backsheet holes. After the photovoltaic module is installed, lamination is performed, and the lamination pressure is also vertical. Horizontally, the pressure relies mainly on the inter-material compression within the butyl rubber. This force cannot guarantee a seamless and tight bond between the current guides and the butyl rubber. Moisture can easily penetrate the module's interior through the vertical gap between the current guides and the butyl rubber. Therefore, the butyl rubber's moisture barrier effect is poor and cannot meet the moisture barrier performance requirements of perovskite photovoltaic modules, thus affecting the module's lifespan. Utility Model Content

[0004] In view of this, the present invention provides a photovoltaic module to solve the problem that existing photovoltaic modules use butyl rubber to seal the backsheet, which has a poor effect on blocking moisture and affects the service life of the photovoltaic module.

[0005] This utility model provides a photovoltaic module, which includes, from bottom to top, a battery cell, a first sealing film, a second sealing film, a water-blocking film and a back sheet. The second sealing film is provided with a first through hole extending in the vertical direction, and the back sheet is provided with a corresponding second through hole extending in the vertical direction. A second sealing element is provided in the second through hole.

[0006] The photovoltaic module also includes a current-guiding strip, which is electrically connected to the battery cell. The current-guiding strip is at least partially sandwiched between the first sealing film and the second sealing film. The current-guiding strip passes through the first through hole, bypasses or passes through the water-blocking membrane, and passes through the second through hole.

[0007] Beneficial Effects: This photovoltaic module, by sandwiching at least a portion of the current-carrying strip between a first sealing film and a second sealing film, effectively prevents moisture from seeping into the battery cell through the second through-hole. Furthermore, the water-blocking film, positioned between the backsheet and the second sealing film, allows the second sealing element to seal the second through-hole after lamination, improving processing convenience and preventing cracking due to excessive pressure during lamination. By sandwiching the current-carrying strip between the first and second sealing films, the lamination pressure strengthens the seal, improving sealing performance. It also increases the length of the current-carrying strip that can be wrapped, thus increasing the path length for moisture intrusion and significantly improving the moisture barrier effect, thereby extending the lifespan of the photovoltaic module.

[0008] In one optional embodiment, with the drainage strip bypassing the water-blocking membrane, the drainage strip extending through the second sealing film includes a drainage section one, a drainage section two, and a drainage section three that are sequentially connected. The drainage section one is sandwiched between the second sealing film and the water-blocking membrane, the drainage section two is sandwiched between the water-blocking membrane and the back plate, and the drainage section three extends out from the second through hole.

[0009] Beneficial effects: With the drain strip bypassing the water-blocking membrane, drain section one is sandwiched between the second sealing film and the water-blocking membrane, and drain section two is sandwiched between the water-blocking membrane and the back plate, which increases the effective length of the drain strip that can be wrapped, thereby increasing the path length of water vapor intrusion and further improving the water-blocking effect. Drain section three passes through the second through hole and is used to connect with the junction box and conduct the current generated by the battery cell.

[0010] In one optional embodiment, the first drainage section and the second drainage section are folded in half and sandwiched between the two sides of the water-blocking membrane, with the outer edge of the water-blocking membrane located on the inner bend side of the fold.

[0011] Beneficial effects: Drainage sections one and two are folded in half and sandwiched between the two sides of the water-blocking membrane. The drainage strip has a continuous structure, requiring no welding, ensuring a relatively flat overall shape and effectively preventing water vapor penetration. The outer edge of the water-blocking membrane is located on the inner bend of the fold, with no gap between the membrane and the drainage strip. Furthermore, the drainage strip completely bypasses the membrane, eliminating the need for perforations and preventing water vapor from entering through the membrane's pores, resulting in better water vapor barrier performance.

[0012] In one optional embodiment, with the drainage strip passing through the water-blocking membrane, the water-blocking membrane is provided with a third through hole for the drainage strip to pass through, and the inner wall of the third through hole is sealed and adhered to the drainage strip.

[0013] Beneficial effects: With the drainage strip passing through the water-blocking membrane, sealing the inner wall of the third through-hole on the water-blocking membrane with the drainage strip prevents moisture from seeping in at the connection between the drainage strip and the third through-hole, further enhancing the moisture barrier effect. Furthermore, the drainage strip passing directly through the water-blocking membrane reduces its length and lowers usage costs.

[0014] In one optional embodiment, the drain strip includes a positive drain strip and a negative drain strip spaced apart. The positive drain strip is electrically connected to the positive electrode of the battery cell, and the negative drain strip is electrically connected to the negative electrode of the battery cell. The second sealing member seals the gap between the positive drain strip, the negative drain strip and the second through hole.

[0015] And / or, the first sealing film further includes a first sealing member extending to the first through hole, the first sealing member sealing the gap between the positive electrode drain strip, the negative electrode drain strip and the first through hole.

[0016] Beneficial effects: The positive electrode guide strip is used to connect the positive terminal of the battery cell, and the negative electrode guide strip is used to connect the negative terminal of the battery cell. The second sealing component, after lamination, seals the gaps between the positive and negative electrode guide strips and the second through hole, preventing moisture from seeping in through the second through hole and also preventing short circuits between the positive and negative electrode guide strips. Using the first sealing component to seal the gaps between the positive and negative electrode guide strips and the first through hole improves the sealing effect and also supports and isolates the positive and negative electrode guide strips, preventing short circuits.

[0017] In one optional embodiment, both the first sealing element and the second sealing element are made of butyl rubber.

[0018] And / or, both the first sealing film and the second sealing film are made of butyl rubber;

[0019] And / or, the projection of the water-blocking membrane along the vertical direction falls within the projections of the first sealing film and the second sealing film along the vertical direction.

[0020] Beneficial effects: Butyl rubber has a low water vapor permeability, effectively blocking water vapor penetration. Furthermore, butyl rubber exhibits strong adhesion to the first and second through-holes, effectively filling the gaps. When the vertical projection of the water-blocking membrane falls within the vertical projections of the first and second sealing sheets, the molten first and second sealing sheets after lamination can cover the sides of the water-blocking membrane, forming a larger water-blocking path and further enhancing the water-blocking effect.

[0021] In one alternative embodiment, the water-blocking membrane has an opposing ETFE side and a PET side in the vertical direction, the ETFE side being connected to the backing plate and the PET side being connected to the second sealing film.

[0022] Beneficial effects: Connecting the PET side to the second sealing film can improve the adhesion between the water-resistant film and the butyl rubber, preventing gaps that could lead to water vapor penetration.

[0023] In one optional embodiment, the water-blocking membrane sequentially comprises an ETFE layer, a first adhesive coating, a transparent aluminum oxide layer, a second adhesive coating, and a PET layer.

[0024] Beneficial effects: The ETFE layer has high light transmittance and self-cleaning properties, reducing power generation losses and effectively blocking external moisture. The first adhesive coating is used to bond the ETFE layer and the transparent alumina layer. The transparent alumina layer has a dense atomic structure, which effectively blocks moisture. The second adhesive coating is used to bond the transparent alumina layer and the PET layer. The PET layer provides structural strength to the water-blocking membrane.

[0025] In one alternative implementation, the first through-hole and the second through-hole coincide in the normal projection of the photovoltaic module.

[0026] Beneficial effect: By aligning the projections of the first and second through holes onto the normal direction of the photovoltaic module, the stress on the backsheet and the second sealing film can be balanced in the first and second through holes.

[0027] In one optional embodiment, the photovoltaic module further includes an encapsulating film disposed between the battery cell and the backsheet, the encapsulating film having clearance holes to avoid the first sealing film, the second sealing film and the water-blocking film.

[0028] Beneficial effects: The adhesive film is used to connect the battery cell and the backplane. The adhesive film has clearance holes, which can prevent the adhesive film from overlapping with the first sealing film and the second sealing film, thus avoiding the failure of water-blocking performance in the overlapping area. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of a photovoltaic module according to an embodiment of the present utility model;

[0031] Figure 2 This is a schematic diagram of another photovoltaic module according to an embodiment of the present utility model;

[0032] Figure 3 This is a bar chart showing the cracking rate of a photovoltaic module according to an embodiment of the present invention compared to other photovoltaic modules;

[0033] Figure 4 This is a bar chart showing the demolding rate of a photovoltaic module according to an embodiment of the present invention compared to other photovoltaic modules.

[0034] Figure 5 This is a bar chart showing the bubble rate of a photovoltaic module according to an embodiment of the present invention compared to other photovoltaic modules.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Battery cell; 2. First sealing film; 3. Second sealing film; 301. First through hole; 4. Water-blocking membrane; 401. Third through hole; 5. Back plate; 501. Second through hole; 6. First sealing element; 7. Second sealing element; 8. Drainage strip; 801. Drainage section one; 802. Drainage section two; 803. Drainage section three; 804. Positive electrode drainage strip; 805. Negative electrode drainage strip; 9. Adhesive film. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0038] The following is combined Figures 1 to 5 The following describes embodiments of the present invention.

[0039] According to embodiments of the present invention, such as Figure 1 As shown, a photovoltaic module is provided, which includes, from bottom to top, a cell 1, a first sealing film 2, a second sealing film 3, a water-blocking film 4, and a backplate 5. The second sealing film 3 is provided with a first through hole 301 extending in the vertical direction, and the backplate 5 is provided with a corresponding second through hole 501 extending in the vertical direction. A second sealing member 7 is provided in the second through hole 501.

[0040] The photovoltaic module also includes a current guide strip 8, which is electrically connected to the cell 1. The current guide strip 8 is at least partially sandwiched between the first sealing film 2 and the second sealing film 3. The current guide strip 8 passes through the first through hole 301, bypasses or passes through the water-blocking membrane 4, and passes through the second through hole 501.

[0041] Therefore, the photovoltaic module provided in this embodiment of the present invention, by sandwiching at least a portion of the guide strip 8 between the first sealing film 2 and the second sealing film 3, and using the first sealing film 2 and the second sealing film 3 to seal and wrap the guide strip 8, and in conjunction with the water-blocking film 4, can effectively prevent water vapor from seeping into the cell 1 along the second through hole 501. Moreover, the water-blocking film 4 is placed between the back plate 5 and the second sealing film 3, and the second sealing member 7 can seal the second through hole 501 after lamination, improving the convenience of processing and avoiding the problem of the second through hole 501 cracking due to excessive pressure during lamination. By sandwiching the guide strip 8 between the first sealing film 2 and the second sealing film 3, the sealing performance of the three parts is stronger through the pressure of lamination, and the length of the guide strip 8 that can be wrapped is increased, thereby increasing the path length of water vapor intrusion, significantly improving the blocking effect on vertical water vapor, and thus improving the service life of the photovoltaic module.

[0042] Specifically, the photovoltaic module also includes a junction box, and the current guide strip 8 extends out from the second through hole 501 and is electrically connected to the junction box. The junction box is glued to the back panel 5 with adhesive.

[0043] In this embodiment of the utility model, the "up" and "down" directions are as follows: Figure 1 As shown by the arrow in the image.

[0044] It should be noted that, in this embodiment of the invention, "cell 1" refers to the front panel glass with a cell film layer, such as a front panel glass containing a perovskite chip. The front panel glass can be transparent conductive glass, tempered glass, or semi-tempered glass, etc.

[0045] It should be noted that this embodiment of the invention does not limit the structure and material of the drainage strip 8, and any existing structure and material can be selected as needed. For example, the drainage strip 8 can be made of tin-plated copper strip.

[0046] In one embodiment, such as Figure 1 As shown, with the drainage strip 8 bypassing the water-blocking membrane 4, the drainage strip 8 that passes through the second sealing film 3 includes a drainage section 1 801, a drainage section 2 802, and a drainage section 3 803 that are sequentially connected. The drainage section 1 801 is sandwiched between the second sealing film 3 and the water-blocking membrane 4, the drainage section 2 802 is sandwiched between the water-blocking membrane 4 and the back plate 5, and the drainage section 3 803 passes through the second through hole 501.

[0047] With the drain strip 8 bypassing the water-blocking membrane 4, drain section one 801 is sandwiched between the second sealing film 3 and the water-blocking membrane 4, and drain section two 802 is sandwiched between the water-blocking membrane 4 and the back plate 5, which increases the effective length of the drain strip 8 that can be wrapped, thereby increasing the path length of water vapor intrusion and further improving the water-blocking effect. Drain section three 803 passes through the second through hole 501 and is used to connect with the junction box and conduct the current generated by the battery cell 1.

[0048] Furthermore, in one embodiment, such as Figure 1 As shown, the first drainage section 801 and the second drainage section 802 are folded and sandwiched between the two sides of the water-blocking membrane 4, with the outer edge of the water-blocking membrane 4 located on the inner bend side of the fold. By folding and sandwiching the first drainage section 801 and the second drainage section 802 between the two sides of the water-blocking membrane 4, the drainage strip 8 has a continuous structure, requiring no welding. This ensures that the drainage strip 8 is relatively flat overall, avoiding unevenness at the welding points that could cause cracking of the water-blocking membrane 4 or the sealing film, effectively preventing water vapor penetration. Furthermore, by sandwiching the water-blocking membrane 4 with the first drainage section 801 and the second drainage section 802, the water-blocking membrane 4 can be limited and fixed, preventing it from shifting during installation and lamination. With the outer edge of the water-blocking membrane 4 located on the inner bend side of the fold, there is no gap between the water-blocking membrane 4 and the drainage strip 8, and the drainage strip 8 completely bypasses the water-blocking membrane 4, eliminating the need for drilling holes in the water-blocking membrane 4. This prevents water vapor from entering through the pores of the water-blocking membrane 4, resulting in better water vapor barrier performance.

[0049] In one embodiment, such as Figure 2 As shown, when the draining strip 8 passes through the water-blocking membrane 4, the water-blocking membrane 4 is provided with a third through hole 401 for the draining strip 8 to pass through, and the inner wall of the third through hole 401 is sealed and adhered to the draining strip 8.

[0050] With the drainage strip 8 passing through the water-blocking membrane 4, the inner wall of the third through hole 401 on the water-blocking membrane 4 is sealed and adhered to the drainage strip 8. This prevents water vapor from seeping in from the connection between the drainage strip 8 and the third through hole 401, further improving the water vapor barrier effect. Moreover, since the drainage strip 8 passes directly through the water-blocking membrane 4, the length of the drainage strip 8 can be reduced, lowering the cost of use.

[0051] In one embodiment, such as Figure 2As shown, the drain strip 8 includes a positive drain strip 804 and a negative drain strip 805 spaced apart. The positive drain strip 804 is electrically connected to the positive electrode of the battery cell 1, and the negative drain strip 805 is electrically connected to the negative electrode of the battery cell 1. The second sealing member 7 seals the gap between the positive drain strip 804, the negative drain strip 805 and the second through hole 501. The positive drain strip 804 is used to connect to the positive electrode of the battery cell 1, and the negative drain strip 805 is used to connect to the negative electrode of the battery cell 1. The second sealing member 7 seals the gap between the positive drain strip 804, the negative drain strip 805 and the second through hole 501 after lamination, preventing moisture from seeping in through the second through hole 501, and also preventing short circuit between the positive drain strip 804 and the negative drain strip 805.

[0052] For ease of installation, in one embodiment, the positive electrode drain strip 804 and the negative electrode drain strip 805 are attached to the wall of the second through hole 501, and the second sealing member 7 seals the second through hole 501.

[0053] In one embodiment, such as Figure 1 and Figure 2 As shown, the first sealing film 2 also includes a first sealing member 6 extending to the first through hole 301. The first sealing member 6 seals the gap between the positive electrode drain strip 804, the negative electrode drain strip 805 and the first through hole 301. By using the first sealing member 6 to seal the gap between the positive electrode drain strip 804, the negative electrode drain strip 805 and the first through hole 301, the sealing effect can be improved, and the positive electrode drain strip 804 and the negative electrode drain strip 805 can also be supported and isolated to prevent short circuit between them.

[0054] Specifically, the first sealing element 6 can be integrally formed with the first sealing film 2, or it can be heat-fused and fixed into a whole during lamination, or the first sealing film 2 can extend into the first through hole 301 to form the first sealing element 6 during lamination and heat fusion. Similarly, the positive electrode drain strip 804 and the negative electrode drain strip 805 can be attached to the hole wall of the first through hole 301, and the first sealing element 6 seals the first through hole 301.

[0055] Specifically, the first sealing element 6 can also be integrally formed with the second sealing film 3. The first through hole 301 is a through hole structure that matches the formation and through opening of the positive electrode drain strip 804 and the negative electrode drain strip 805, so that the positive electrode drain strip 804 and the negative electrode drain strip 805 can just pass through. Then the first sealing element 6 is a part of the adhesive in the body of the second sealing film 3 located between the positive electrode drain strip 804 and the negative electrode drain strip 805. It can be heat-melted and fixed into a whole during lamination to seal the first through hole 301 and seal and bond it to the positive electrode drain strip 804 and the negative electrode drain strip 805.

[0056] In one embodiment, both the first sealing element 6 and the second sealing element 7 are made of butyl rubber.

[0057] And / or, both the first sealing film 2 and the second sealing film 3 are made of butyl rubber.

[0058] Butyl rubber has a low water vapor permeability, which can effectively block water vapor penetration. Furthermore, butyl rubber has strong adhesion to the first through hole 301 and the second through hole 501, which can effectively fill the gap.

[0059] In one embodiment, the vertical projection of the water-blocking membrane 4 falls within the vertical projections of the first sealing sheet 2 and the second sealing sheet 3. By placing the vertical projection of the water-blocking membrane 4 within the vertical projections of the first sealing sheet 2 and the second sealing sheet 3, the molten first sealing sheet 2 and the second sealing sheet 3 after lamination can cover the sides of the water-blocking membrane 4, forming a larger water-blocking path and further improving the water-blocking effect.

[0060] In one embodiment, the water-blocking membrane 4 has an ETFE (ethylene-tetrafluoroethylene copolymer) side and a PET (polyethylene terephthalate) side facing each other in the vertical direction. The ETFE side is connected to the backing plate 5, and the PET side is connected to the second sealing film 3. The connection between the PET side and the second sealing film 3 improves the adhesion between the water-blocking membrane 4 and the butyl rubber, preventing gaps that could allow moisture penetration. If the ETFE side is connected to the second sealing film 3, the adhesion between the ETFE side and the second sealing film 3 is poor, making it easier for gaps to form and allowing moisture to penetrate.

[0061] Further, in one embodiment, the water-blocking membrane 4 sequentially comprises an ETFE layer, a first adhesive coating, a transparent alumina layer, a second adhesive coating, and a PET layer. The ETFE layer has high light transmittance and self-cleaning properties, which can reduce power generation losses and effectively block external moisture. The first adhesive coating is used to bond the ETFE layer and the transparent alumina layer. The first adhesive coating can be a UV-resistant adhesive coating. The transparent alumina layer has a dense atomic structure, which can effectively block moisture. The second adhesive coating is used to bond the transparent alumina layer and the PET layer. The PET layer provides structural strength to the water-blocking membrane 4.

[0062] In one embodiment, the first through-hole 301 and the second through-hole 501 are projected onto the normal direction of the photovoltaic module. This alignment of the first through-hole 301 and the second through-hole 501 onto the normal direction of the photovoltaic module helps to balance the stress on the backsheet 5 and the second sealing film 3 at the first through-hole 301 and the second through-hole 501, preventing cracking at the second through-hole 501 during lamination.

[0063] In one embodiment, such as Figure 1 and Figure 2As shown, the photovoltaic module also includes an encapsulant film 9, which is disposed between the battery cell 1 and the backsheet 5. The encapsulant film 9 has clearance holes to avoid the first sealing film 2, the second sealing film 3, and the water-blocking film 4. The encapsulant film 9 is used to connect the battery cell 1 and the backsheet 5. The clearance holes in the encapsulant film 9 can prevent the encapsulant film 9 from overlapping with the first sealing film 2 and the second sealing film 3, which would cause the water-blocking performance of the overlapping area to fail.

[0064] In addition, the drain strip 8 is located on the side of the adhesive film 9 close to the battery cell 1, and passes through the clearance hole, then passes through the first sealing film 2 and the second sealing film 3 to enter the first through hole 301, then bypasses or passes through the water-blocking film 4, and passes through the second through hole 501 to connect with the junction box.

[0065] Alternatively, the drainage strip 8 can pass directly through the adhesive membrane 9, then pass between the first sealing film 2 and the second sealing film 3 to enter the first through hole 301, then bypass or pass through the water-blocking membrane 4, and pass through the second through hole 501 to connect with the junction box.

[0066] In one embodiment, a waterproof tape is applied to the periphery of the photovoltaic module, covering the battery cell 1, backsheet 5, and adhesive film 9, for peripheral water blocking of the photovoltaic module. The waterproof tape can also be made of butyl rubber.

[0067] The manufacturing process of the photovoltaic module according to this embodiment of the utility model is as follows:

[0068] The positive terminal of cell 1 is electrically connected to the positive terminal lead bar 804, and the negative terminal of cell 1 is connected to the negative terminal lead bar 805. A first sealing film 2 is placed on the upper surface of cell 1.

[0069] The positive electrode drain strip 804 and the negative electrode drain strip 805 extend from both sides along the upper surface of the first sealing film 2 and stand upright in the middle area. Furthermore, the positive electrode drain strip 804 and the negative electrode drain strip 805 are spaced apart at the middle position of the first sealing film 2.

[0070] The gap between the positive electrode drain bar 804 and the negative electrode drain bar 805 is sealed using the first sealing component 6.

[0071] A second sealing sheet 3 is placed above the first sealing sheet 2. The first through hole 301 on the second sealing sheet 3 is aligned with the first sealing member 6, and the positive electrode drain strip 804 and the negative electrode drain strip 805 pass through the first through hole 301. The first sealing member 6 also seals the gaps between the positive electrode drain strip 804, the negative electrode drain strip 805 and the first through hole 301.

[0072] The positive electrode drain strip 804 and the negative electrode drain strip 805 are pressed flat along the upper surface of the second sealing film 3 and extended in opposite directions.

[0073] A water-blocking film 4 is placed on top of the second sealing film 3, with the ETFE side of the water-blocking film 4 facing upwards and the PET side in contact with the second sealing film 3.

[0074] Fold the positive electrode drain strip 804 and the negative electrode drain strip 805 upwards along both sides of the water-blocking membrane 4, then flatten them along the upper surface of the water-blocking membrane 4 and stand them upright at the center of the water-blocking membrane 4.

[0075] Waterproof tape is applied along the periphery of cell 1.

[0076] A film 9 is applied to the upper surface of the cell 1. The positive electrode lead strip 804 and the negative electrode lead strip 805 pass through the clearance holes of the film 9, and the first sealing film 2 below does not overlap with the film 9.

[0077] The backplate 5 is laid on top of the adhesive film 9, and the positive electrode drain strip 804 and the negative electrode drain strip 805 pass through the second through hole 501 respectively.

[0078] The semi-finished photovoltaic module is fed into a laminator and laminated using a low-temperature process to fix the cell 1, the first sealing film 2, the second sealing film 3, the water-blocking film 4, the back plate 5, and the drain strip 8 into a whole.

[0079] A second sealing element 7 is applied using a glue applicator inside the second through hole 501 and between the positive electrode lead strip 804 and the negative electrode lead strip 805. The second sealing element 7 is required to seal the gaps between the positive electrode lead strip 804, the negative electrode lead strip 805 and the second through hole 501.

[0080] It should be noted that, in order to block vertical water vapor, photovoltaic modules can also employ an external or internal hole-sealing process in conjunction with a water-blocking membrane. Both external and internal hole-sealing processes require lamination fixation after hole sealing. The photovoltaic module of this embodiment can be sealed after lamination; therefore, the photovoltaic module of this embodiment is also a "post-lamination hole-sealing" structure.

[0081] For example, a photovoltaic module with an externally plugged structure includes, in sequence, a water-blocking membrane, a first sealing film, a plugging adhesive, a perforating adhesive, a drain strip, and a second sealing film.

[0082] A photovoltaic module with an internally plugged structure includes, in sequence, plugging adhesive, perforating adhesive, a drain strip, a sealing film, and a water-blocking membrane.

[0083] The appearance of the photovoltaic module with external hole-blocking structure, the photovoltaic module with internal hole-blocking structure, and the photovoltaic module of this embodiment were inspected. The inspection results are shown in Table 1.

[0084] Table 1: Test Results

[0085] Number of experiments 200 200 200 Number of fragments 103 5 0 Fragmentation rate 51.5％ 2.5％ 0％ Number of films removed 0 183 0 Demolding rate 0％ 91.5％ 0％ Number of bubbles 0 200 0 bubble rate 0％ 100.0％ 0％

[0086] Combined with Table 1, Figure 3 , Figure 4 and Figure 5 It can be seen that the thickness of the butyl rubber in the second through hole 501 of the photovoltaic module using this embodiment of the utility model is reduced, and the water-blocking film 4 is set between the second sealing film 3 and the back plate 5, which significantly reduces the cracking rate, demolding rate and bubble rate of the photovoltaic module, has a better water vapor barrier effect, a longer service life, a higher processing yield, and reduces manufacturing costs, which is conducive to promotion.

[0087] In photovoltaic modules with externally plugged holes, the thickness at the holes in the backsheet differs significantly from the rest of the area. During lamination, pressure acts on the holes in the backsheet, creating stress that can easily cause the entire module to crack, resulting in a high cracking rate for photovoltaic modules.

[0088] In photovoltaic modules with internally plugged holes, the thickness of the butyl rubber at the holes in the backsheet is transferred into the holes, releasing stress and reducing the cracking rate. However, after stress release, it easily affects the film layer, causing film peeling, resulting in a high peeling rate. Furthermore, the PET side of the water-blocking film is in contact with the outside, and the PET side will hydrolyze in a long-term high-humidity environment, causing water-blocking failure, resulting in a high bubble rate.

[0089] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A photovoltaic module, characterized in that, From bottom to top, it includes a battery cell (1), a first sealing film (2), a second sealing film (3), a water-blocking membrane (4), and a back plate (5). The second sealing film (3) has a first through hole (301) that runs through the vertical direction. The back plate (5) has a corresponding second through hole (501) that runs through the vertical direction. The second through hole (501) has a second sealing element (7) inside it. The photovoltaic module also includes a flow guide (8), which is electrically connected to the cell (1). The flow guide (8) is at least partially sandwiched between the first sealing film (2) and the second sealing film (3). The flow guide (8) passes through the first through hole (301), bypasses or passes through the water-blocking membrane (4), and passes through the second through hole (501).

2. The photovoltaic module according to claim 1, characterized in that, With the drainage strip (8) bypassing the water-blocking membrane (4), the drainage strip (8) that passes through the second sealing film (3) includes a drainage section one (801), a drainage section two (802), and a drainage section three (803) that are sequentially connected. The drainage section one (801) is sandwiched between the second sealing film (3) and the water-blocking membrane (4), the drainage section two (802) is sandwiched between the water-blocking membrane (4) and the back plate (5), and the drainage section three (803) passes through the second through hole (501).

3. The photovoltaic module according to claim 2, characterized in that, The first drainage section (801) and the second drainage section (802) are folded in half and sandwiched on both sides of the water-blocking membrane (4), with the outer edge of the water-blocking membrane (4) located on the inner side of the fold.

4. The photovoltaic module according to claim 1, characterized in that, With the drain strip (8) passing through the water-blocking membrane (4), the water-blocking membrane (4) is provided with a third through hole (401) for the drain strip (8) to pass through, and the inner wall of the third through hole (401) is sealed and adhered to the drain strip (8).

5. The photovoltaic module according to claim 1, characterized in that, The drain strip (8) includes a positive drain strip (804) and a negative drain strip (805) spaced apart. The positive drain strip (804) is electrically connected to the positive electrode of the battery cell (1), and the negative drain strip (805) is electrically connected to the negative electrode of the battery cell (1). The second sealing member (7) seals the gap between the positive drain strip (804), the negative drain strip (805) and the second through hole (501). And / or, the first sealing film (2) further includes a first sealing member (6) extending to the first through hole (301), the first sealing member (6) sealing the gap between the positive electrode drain strip (804), the negative electrode drain strip (805) and the first through hole (301).

6. The photovoltaic module according to claim 5, characterized in that, Both the first sealing element (6) and the second sealing element (7) are made of butyl rubber. And / or, both the first sealing film (2) and the second sealing film (3) are made of butyl rubber; And / or, the projection of the water-blocking membrane (4) in the vertical direction falls within the projection of the first sealing film (2) and the second sealing film (3) in the vertical direction.

7. The photovoltaic module according to any one of claims 1 to 6, characterized in that, The water-blocking membrane (4) has an ETFE side and a PET side in the vertical direction. The ETFE side is connected to the back plate (5), and the PET side is connected to the second sealing film (3).

8. The photovoltaic module according to claim 7, characterized in that, The water-blocking membrane (4) comprises, in sequence, an ETFE layer, a first adhesive coating, a transparent aluminum oxide layer, a second adhesive coating, and a PET layer.

9. The photovoltaic module according to any one of claims 1 to 5, characterized in that, The first through hole (301) and the second through hole (501) coincide in the normal projection of the photovoltaic module.

10. The photovoltaic module according to any one of claims 1 to 6, characterized in that, The photovoltaic module also includes an encapsulant film (9), which is disposed between the battery cell (1) and the backplate (5). The encapsulant film (9) has clearance holes to avoid the first sealing film (2), the second sealing film (3) and the water-blocking film (4).

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