Preparation method of battery string, photovoltaic module and film belt processing mechanism

Abstract

The embodiment of the invention relates to the field of photovoltaic technology, provides a preparation method of a battery string, a photovoltaic module and a film belt processing mechanism, and aims to reduce the possibility of subfissure and fragment of a battery piece of the photovoltaic module in the lamination and transportation process as much as possible so as to improve the product quality. The preparation method of the battery string comprises the following steps: fixing a battery piece and an adhesive film tape by adopting a first heating process; wherein the adhesive film belt is arranged on the front surface of the edge of the battery piece and / or the back surface of the edge of the battery piece; arranging a plurality of battery pieces along a first direction; wherein the arrangement direction of the adhesive film belt is intersected with the first direction; solder strips are arranged on the adjacent battery pieces in the first direction; wherein the welding strip and the adhesive film strip are arranged in a crossed mode, and the welding strip is arranged on the side, away from the battery piece, of the adhesive film strip; and respectively fixing the welding strip with the adhesive film strip and the battery piece by adopting a second heating process.

Description

Technical Field

[0001] The present disclosure relates to the field of photovoltaic technology, and particularly to a method for manufacturing a battery string, a photovoltaic module, and a film strip processing mechanism. Background Art

[0002] Photovoltaic power generation converts solar energy into electrical energy through photovoltaic modules, thereby providing a green, environmentally friendly, and renewable energy production method, which has been widely used in multiple fields. A photovoltaic module includes a battery string formed by connecting a plurality of battery cells. During lamination and transportation, the battery cells are prone to hidden cracks and fragmentation problems, thereby reducing product quality. Summary of the Invention

[0003] Embodiments of the present disclosure provide a method for manufacturing a battery string, a photovoltaic module, and a film strip processing mechanism to minimize the possibility of hidden cracks and fragmentation of the battery cells of the photovoltaic module during lamination and transportation, thereby improving product quality.

[0004] According to some embodiments of the present disclosure, on the one hand, an embodiment of the present disclosure provides a method for manufacturing a battery string, including:

[0005] Fixing a battery cell to a film strip using a first heating process; wherein, the film strip is disposed on the front side and / or the back side of the edge of the battery cell;

[0006] Arranging a plurality of the battery cells along a first direction; wherein, the arrangement direction of the film strip intersects with the first direction;

[0007] Arranging welding tapes on adjacent battery cells along the first direction; wherein, the welding tapes are arranged in a crossed manner with the film strip, and the welding tapes are disposed on a side of the film strip away from the battery cell;

[0008] Fixing the welding tapes to the film strip and the battery cells respectively using a second heating process.

[0009] According to some embodiments of the present disclosure, before fixing the battery cell to the film strip using the first heating process, the manufacturing method further includes:

[0010] Cutting a film along a first cutting direction to obtain a film block; wherein, the first cutting direction intersects with the extending direction of the film, and the dimension of the film block along the extending direction of the film is the same as the dimension of the battery cell along the first direction;

[0011] Cutting the film block along a second cutting direction to obtain the film strip; wherein, the second cutting direction is the length direction or the width direction of the film block.

[0012] According to some embodiments of the present disclosure, cutting the adhesive film along the first cutting direction includes:

[0013] Using a film strip processing mechanism to cut the adhesive film along the first cutting direction; wherein, the film strip processing mechanism includes a film strip processing plate, and the film strip processing plate is provided with a plurality of parallel grooves; the length direction of the grooves is parallel to the first cutting direction.

[0014] According to some embodiments of the present disclosure, using the film strip processing mechanism to cut the adhesive film along the first cutting direction includes:

[0015] Adsorbing the adhesive film to the film strip processing plate; wherein, the length direction of the grooves intersects with the extending direction of the adhesive film;

[0016] Determining the cutting position of the adhesive film according to the size of the adhesive film block, wherein the cutting position of the adhesive film corresponds to the position of at least one of the grooves;

[0017] Cutting the adhesive film along the first cutting direction at the cutting position to obtain the adhesive film block.

[0018] According to some embodiments of the present disclosure, cutting the adhesive film block along the second cutting direction includes:

[0019] Using the film strip processing mechanism to cut the adhesive film block along the second cutting direction; wherein, the second cutting direction is parallel to the length direction of the grooves.

[0020] According to some embodiments of the present disclosure, using the film strip processing mechanism to cut the adhesive film block along the second cutting direction includes:

[0021] Adsorbing the adhesive film block to the film strip processing plate; wherein, the length direction of the grooves is parallel to the length direction or the width direction of the adhesive film block;

[0022] Cutting at the positions corresponding to the two opposite inner walls of the adhesive film block and at least one of the grooves to obtain at least one adhesive film strip; wherein, the width of the adhesive film strip is the same as the width of the groove, and the length of the groove is greater than the length of the adhesive film strip.

[0023] According to some embodiments of the present disclosure, using the first heating process to fix the battery cell and the adhesive film strip includes:

[0024] Using the first heating process to heat the battery cell;

[0025] Fixing the adhesive film strip on the front side and / or the back side of the edge of the heated battery cell.

[0026] According to some embodiments of the present disclosure, fixing the cell piece to the film tape by using the first heating process includes:

[0027] Heating the film tape by using the first heating process;

[0028] Fixing the heated film tape on the front side and / or the back side of the edge of the cell piece.

[0029] According to some embodiments of the present disclosure, the heating temperature range of the first heating process is [50°C, 120°C]; the material of the film tape is a non-pre-crosslinked material; the grammage range of the film tape is [100 g / m^2, 200 g / m^2]; the thickness range of the film tape is [0.1 mm, 0.3 mm].

[0030] According to some embodiments of the present disclosure, on the other hand, an embodiment of the present disclosure provides a photovoltaic module, including:

[0031] A battery string formed by using the preparation method of the above battery string;

[0032] An encapsulation film for covering the surface of the battery string;

[0033] A cover plate for covering the surface of the encapsulation film facing away from the battery string.

[0034] According to some embodiments of the present disclosure, on yet another aspect, an embodiment of the present disclosure provides a film tape processing mechanism applied to the preparation method of the above battery string;

[0035] The film tape processing mechanism includes a film tape processing plate, and the film tape processing plate is provided with a plurality of parallel grooves.

[0036] According to some embodiments of the present disclosure, the length direction of the groove is the same as the length direction of the film tape of the battery string; the width of the film tape is the same as the width of the groove, and the length of the groove is greater than the length of the film tape.

[0037] The disclosed embodiment provides a method for preparing a battery string, a photovoltaic module and a film strip processing mechanism. In the method for preparing the battery string, a first heating process is first used to fix the battery cell and the adhesive film strip, and the adhesive film strip is set on the front side of the edge of the battery cell and / or the back side of the edge of the battery cell; then a plurality of battery cells are set along a first direction, and the setting direction of the adhesive film strip intersects with the first direction; then, welding strips are set on adjacent battery cells along the first direction; wherein the welding strips are cross-set with the adhesive film strip, and the welding strips are set on the side of the adhesive film strip away from the battery cell; finally, a second heating process is used to fix the welding strips to the adhesive film strip and the battery cell, respectively. In this way, on the one hand, the adhesive film strip can be accurately set at the edge of the battery cell, so that the stress on the edge of the battery cell is dispersed by the adhesive film strip, thereby minimizing the possibility of hidden cracks and breakage of the battery cells of the photovoltaic module during lamination and transportation, thereby improving product quality. On the other hand, in the preparation method provided in the embodiment of the present application, the adhesive film tape is fixed to the front of the edge of the battery cell and / or the back of the edge of the battery cell before setting the welding tape. Compared with the related art of inserting the film after the battery cells are strung together, it avoids breaking the battery string, inserting the film and heating the battery string, so there is no need to set the opening angle of the battery cell, reducing the risk of Pad desoldering and the risk of adhesive film tape falling off. On the other hand, the preparation method of the battery string provided in the embodiment of the present application has no requirements for the type of battery cell and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings, and these exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A schematic diagram of a process for preparing a battery string provided in an embodiment of the present disclosure;

[0040] Figures 2 - 5 A schematic top view of various adhesive film tapes and battery cells provided in an embodiment of the present disclosure;

[0041] Figures 6 - 8 A schematic side view of various adhesive film tapes and battery cells provided in an embodiment of the present disclosure;

[0042] Figure 9 A schematic diagram of the structure of a battery string provided in an embodiment of the present disclosure;

[0043] Figure 10Another structural schematic diagram of a battery string provided by an embodiment of the present disclosure;

[0044] Figure 11 Another process schematic diagram of a preparation method of a battery string provided by an embodiment of the present disclosure;

[0045] Figure 12 A structural schematic diagram of a film strip processing mechanism provided by an embodiment of the present disclosure;

[0046] Figure 13 A top view schematic diagram of a film strip processing mechanism provided by an embodiment of the present disclosure;

[0047] Figure 14 A schematic diagram of cutting a glue film provided by an embodiment of the present disclosure;

[0048] Figure 15 A schematic diagram of cutting a glue film block provided by an embodiment of the present disclosure;

[0049] Figure 16 A structural schematic diagram of a film strip feeding mechanism provided by an embodiment of the present disclosure;

[0050] Figure 17 A structural schematic diagram of placing a glue film strip by a film strip placing and taking mechanism provided by an embodiment of the present disclosure;

[0051] Figure 18 A partial three-dimensional structural schematic diagram of a photovoltaic module provided by an embodiment of the present disclosure;

[0052] Figure 19 is Figure 18 A sectional structural schematic diagram along the section direction NN1. Detailed implementation manners

[0053] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the technical solutions of the present disclosure will be clearly and completely described below in conjunction with specific embodiments of the present disclosure and the corresponding drawings. Apparently, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

[0054] In the description of the embodiments of the present disclosure, the meaning of "at least one" is one or more, the meaning of "at least one layer" is one layer or more layers, the meaning of "a plurality of" is two or more, the meaning of "multiple layers" is two or more layers, the meaning of "multiple groups" is two or more groups, and the meaning of "multiple pieces" is two or more pieces, unless otherwise clearly and specifically defined.

[0055] In the description of the embodiments of the present disclosure, technical terms such as "first" and "second" are only used to distinguish different objects, and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity, specific order or primary-secondary relationship of the indicated technical features.

[0056] In the description of the embodiments of the present disclosure, the term "and / or" is merely a description of the association relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: the existence of A, the simultaneous existence of A and B, and the existence of B. Additionally, the character " / " in this document generally represents an "or" relationship between the associated objects before and after.

[0057] Referring to "embodiments" in this document means that the specific features, structures or characteristics described in connection with the embodiments may be included in at least one embodiment of the present disclosure. The phrase appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0058] In the description of the embodiments of the present disclosure, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the embodiments of the present disclosure. For example, if the device or element in the drawing is inverted, then the element described as "below" or "beneath" or "under" or "at the bottom" of other elements or features will be oriented "above" or "at the top" of the said other elements or features. Therefore, the term "below" can cover both the upper and lower orientations depending on the context in which the term is used, which will be obvious to those of ordinary skill in the art. The material can be oriented in other ways (e.g., rotated 90 degrees, inverted, flipped), and the spatial relative descriptive terms used herein can be interpreted accordingly.

[0059] In the description of the embodiments of the present disclosure, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0060] In the corresponding drawings of the embodiments of the present disclosure, for better understanding and convenience of description, the thickness and area of the layer are enlarged. In addition, when it is described that a component is "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor on a partial edge of the entire surface.

[0061] In the description of the embodiments of the present disclosure, when a certain component "includes" another component, unless otherwise specified, other components are not excluded, and other components may further be included. That the second component is formed or disposed above or on the first component, or that the second component is formed or disposed on the surface of the first component, or that the second component is formed or disposed on one side of the first component, may include embodiments where the first component and the second component are in direct contact, and may also include embodiments where additional components may be provided between the first component and the second component, such that the first component and the second component may not be in direct contact. For simplicity and clarity, various components can be drawn at any scale. In the drawings, some layers / components may be omitted for simplicity. Unless otherwise specified, that the second component is formed or disposed on the surface of the first component means that the first component is in direct contact with the second component. Among them, the above "components" may refer to: layers, films, regions, parts, structures, etc.

[0062] In the related art, to address the problems of hidden cracks and broken pieces in the battery cells of photovoltaic modules, a method of directly adding a buffer material to the battery string is mostly adopted. Specifically, the gap plugging film technology is used, that is, after the battery cells are strung together, processes such as breaking the battery string, inserting the film, and heating are carried out. However, for battery strings using the multi-piece technology and the negative pitch technology, this solution has the disadvantages of requiring an opening angle of the battery cells, low film plugging accuracy, a risk of pad (welding pad) de-soldering, and easy film peeling during the movement of the photovoltaic module, and can no longer solve the existing problems. In the related art, the low-temperature film coating technology is also used to achieve gap plugging film, but this technology can only be applied to double-glass modules and has a reliability risk for single-glass modules.

[0063] Based on this, the embodiments of the present disclosure provide a method for preparing a battery string, as shown in reference to Figure 1 shown, including:

[0064] S1. Fix the battery cell and the adhesive film tape by using the first heating process; wherein, the adhesive film tape is disposed on the front side and / or the back side of the edge of the battery cell.

[0065] In the embodiment of the present application, the principle of fixing the battery cell and the adhesive film tape by using the first heating process is as follows: the adhesive film tape will melt after being heated, so it has a certain viscosity; therefore, the adhesive film tape and the battery cell can be fixed by the heating process. It should be noted that here the first heating process can be to heat the battery cell, and then dispose the adhesive film tape on the front side and / or the back side of the edge of the heated battery cell. The heated battery cell conducts heat to the adhesive film tape, causing the adhesive film tape to melt and generate viscosity, so as to be bonded and fixed to the battery cell. Or, the first heating process can also be to heat the adhesive film tape to make the adhesive film tape melt and generate viscosity, and then fix the heated adhesive film tape on the front side and / or the back side of the edge of the battery cell.

[0066] In the embodiment of the present application, the specific heating method adopted by the first heating process is not limited. For example, the first heating process can adopt non-contact heating methods such as infrared welding process or laser welding process; or, the first heating process can also adopt a contact heating method for heating. For example, by pre-heating the belt or the placement platform of the string welding machine, and then placing the battery cell or the adhesive film on the pre-heated belt or the pre-heated placement platform, so as to realize the heating of the battery cell or the adhesive film.

[0067] In the embodiment of the present application, the adhesive film tape can be disposed on the front side of the edge of the battery cell. For example, referring to Figure 2 and Figure 6 as shown, the adhesive film tape 1 is disposed on the front side 201 of a long edge of the battery cell 2; or, the adhesive film tape can be disposed on the front side and the back side of the edge of the battery cell. For example, referring to Figure 7 as shown, the adhesive film tape 1 is respectively disposed on the front side 201 and the back side 202 of an edge of the battery cell 2; or, the adhesive film tape can be disposed on the back side of the edge of the battery cell. For example, referring to Figure 8 as shown, the adhesive film tape 1 is disposed on the back side 202 of an edge of the battery cell 2.

[0068] In the embodiment of the present application, the battery cell is generally rectangular, and the battery cell includes two relatively arranged long edges and two relatively arranged wide edges; according to actual needs, the adhesive film tape can be disposed on any one of the long edges or any one of the wide edges of the battery cell. For example, referring to Figure 2 as shown, the adhesive film tape 1 is disposed on the wide edge on the right side of the battery cell 2; or, the adhesive film tape is disposed on both two relatively arranged long edges or two relatively arranged wide edges of the battery cell. For example, referring toFigure 3 As shown, a film tape 1 is provided on two relatively arranged wide edges of the cell 2. Refer to Figure 4 As shown, a film tape 1 is provided on two relatively arranged long edges of the cell 2; alternatively, film tapes are provided on all edges of the cell. For example, refer to Figure 5 As shown, a film tape 1 is provided on two long edges and two wide edges of the cell 2.

[0069] In the embodiments of the present application, the type of the cell is not limited. The cell includes but is not limited to a PERC cell (Passivated Emitter Rear Cell), an IBC cell (Interdigitated Back Contact), a TOPCon cell (Tunnel Oxide Passivated Contact), a HIT / HJT cell (Heterojunction Technology), a thin-film solar cell, or any combination of stacked cells. Among them, the thin-film solar cell includes but is not limited to a perovskite thin-film solar cell, a copper indium selenide thin-film solar cell, a gallium arsenide thin-film solar cell, and a cadmium sulfide thin-film solar cell. The stacked cell includes but is not limited to a perovskite cell stacked with a crystalline silicon cell, a perovskite cell stacked with a perovskite cell, and a perovskite cell stacked with a thin-film cell. The size of the cell is also not limited. For example, the cell can be a complete cell, a half cell, or a quarter cell.

[0070] S2. Refer to Figure 9 As shown, a plurality of cells 2 are arranged along the first direction AB; wherein, the setting direction A1B1 of the film tape 1 intersects with the first direction AB.

[0071] In the embodiments of the present application, refer to Figure 9 As shown, the intersection angle α between the setting direction A1B1 of the film tape 1 and the first direction AB is not limited. For example, the intersection angle α between the setting direction of the film tape and the first direction can be 70 degrees, 80 degrees, 90 degrees, 100 degrees, or 110 degrees, etc. To facilitate the dispersion of the stress on the edge of the cell, as Figure 9 As shown, the setting direction A1B1 of the film tape 1 is perpendicular to the first direction AB.

[0072] S3. Refer to Figure 10 As shown, a welding tape 3 is arranged on adjacent cells 2 along the first direction AB; wherein, the welding tape 3 is arranged in a cross manner with the film tape 1, and the welding tape 3 is arranged on the side of the film tape 1 away from the cell 2.

[0073] In the embodiment of the present application, in order to improve the setting efficiency and setting accuracy, a string welding machine can be used to set the welding strip. It should be noted that the number of welding strips can be determined according to the actual situation. The setting of the welding strips of adjacent battery cells is related to the arrangement direction of the electrodes of the adjacent battery cells. If the electrodes with positive polarity of adjacent battery cells are arranged on the same side, the welding strip connects different sides of the two adjacent battery cells; if the electrodes of the adjacent battery cells arranged on the same side have opposite polarities, the welding strip connects the same side of the two adjacent battery cells.

[0074] S4, using the second heating process to fix the soldering tape to the adhesive tape and the battery cell respectively. Then, the part of the soldering tape that crosses the adhesive tape is fixed to the adhesive tape, and the rest is fixed to the battery cell, so as to avoid the soldering tape and the battery cell from being welded together, thereby reducing the harpoon distance (i.e., the spacing between adjacent battery cells) and achieving the effect of increasing the power of the module.

[0075] In the embodiment of the present application, the specific heating method used in the second heating process is not limited. For example, the second heating process can use an infrared welding process or a laser welding process. Since the soldering tape and the adhesive film tape are arranged crosswise, the intersection of the soldering tape and the adhesive film tape is the fixing point of the two. Since the laser welding process has high welding accuracy and strong temperature controllability, in order to avoid the remaining part of the adhesive film tape from falling off due to heat in step S4, in order to eliminate reliability risks, the laser welding process can be used to fix the soldering tape to the adhesive film tape and the battery cell respectively.

[0076] In the preparation method of the battery string provided in the embodiment of the present application, the battery cell and the adhesive film tape are first fixed by a first heating process, and the adhesive film tape is set on the front side of the edge of the battery cell and / or the back side of the edge of the battery cell; then a plurality of battery cells are set along a first direction, and the setting direction of the adhesive film tape intersects with the first direction; then, welding strips are set on adjacent battery cells along the first direction; wherein the welding strips and the adhesive film tape are cross-set, and the welding strips are set on the side of the adhesive film tape away from the battery cell; finally, the welding strips are fixed to the adhesive film tape and the battery cell respectively by a second heating process. In this way, on the one hand, the adhesive film tape can be accurately set at the edge position of the battery cell, so that the stress on the edge of the battery cell is dispersed by the adhesive film tape, thereby minimizing the possibility of hidden cracks and breakage of the battery cells of the photovoltaic module during lamination and transportation, thereby improving product quality. On the other hand, in the preparation method provided in the embodiment of the present application, the adhesive film tape is fixed to the front of the edge of the battery cell and / or the back of the edge of the battery cell before setting the welding tape. Compared with the related art of inserting the film after the battery cells are strung together, it avoids breaking the battery string, inserting the film and heating the battery string, so there is no need to set the opening angle of the battery cell, reducing the risk of Pad desoldering and the risk of adhesive film tape falling off. On the other hand, the preparation method of the battery string provided in the embodiment of the present application has no requirements for the type of battery cell and has a wide range of applications.

[0077] In one or more embodiments, with reference to Figure 11 as shown in

[0078] S10. Before fixing the battery cell and the adhesive film tape by using the first heating process in step S1, the preparation method further includes:

[0079] S10. Cut the adhesive film along the first cutting direction to obtain an adhesive film block; wherein, the first cutting direction intersects with the extending direction of the adhesive film, and the dimension of the adhesive film block along the extending direction of the adhesive film is the same as the dimension of the battery cell along the first direction. Figure 16 For the convenience of storage and transportation, the adhesive film can be arranged in a wound and coiled manner. When cutting the adhesive film, a film tape loading mechanism 6 as shown in

[0080] can be used for loading, that is, pulling the wound and coiled adhesive film flat for cutting. The specific structure of the film tape loading mechanism can refer to the related art and will not be elaborated here. The width of the film roll of the adhesive film can be 12 mm - 200 mm; for example: 12 mm, 30 mm, 50 mm, 70 mm, 90 mm, 110 mm, 130 mm, 150 mm, 190 mm or 200 mm, and specifically can be determined according to the number of pieces processed simultaneously.

[0081] In the embodiments of the present application, the dimension of the adhesive film block along the extending direction of the adhesive film can be 156 mm - 230 mm, specifically, it can be 156 mm, 165 mm, 175 mm, 185 mm, 195 mm, 205 mm, 215 mm, 225 mm or 230 mm.

[0082] In practice, the sizes of the battery cells are different. When the width of the battery cell is determined, only by controlling the dimension of the adhesive film block along the extending direction of the adhesive film, an adhesive film block adapted to different-sized battery cells can be obtained.

[0083] S20. Cut the adhesive film block along the second cutting direction to obtain an adhesive film tape; wherein, the second cutting direction is the length direction or the width direction of the adhesive film block.

[0084] In the embodiments of the present application, the specific cutting methods for step S10 and step S20 are not limited. Since the adhesive film is relatively thin and the width of the adhesive film tape is relatively small, in order to cut more precisely and quickly, the embodiments of the present application provide a film tape processing mechanism to facilitate the cutting of the adhesive film and the adhesive film block.

[0085] Specifically, step S10. Cutting the adhesive film along the first cutting direction includes:

[0086] S10’. Use the film strip processing mechanism to cut the adhesive film along the first cutting direction; wherein, refer to Figure 12 and Figure 13 As shown, the film strip processing mechanism includes a film strip processing plate 4, and the film strip processing plate 4 is provided with a plurality of parallel grooves 41; the length direction CD of the grooves 41 is parallel to the first cutting direction. The depth of the grooves of the film strip processing plate can be less than or equal to the thickness of the film strip processing plate. It should be noted that in order to facilitate the cutting knife to cut along the grooves, the bottom of the grooves can be hollowed out.

[0087] The following specifically describes how to use the film strip processing mechanism to cut the adhesive film.

[0088] Specifically, step S10’. Use the film strip processing mechanism to cut the adhesive film along the first cutting direction, including:

[0089] S101. Refer to Figure 13 and 14 As shown, adsorb the adhesive film 5 to the film strip processing plate 4; wherein, the length direction CD of the groove 41 intersects with the extension direction C0D0 of the adhesive film 5.

[0090] Exemplarily, the vacuum adsorption method can be used to adsorb the adhesive film to the film strip processing plate; refer to Figure 12 As shown, a plurality of air holes 42 can be provided on the film strip processing plate 4 to facilitate vacuum adsorption.

[0091] S102. Determine the cutting position of the adhesive film according to the size of the adhesive film block, wherein the cutting position of the adhesive film corresponds to the position of at least one groove.

[0092] S103. Refer to Figure 14 As shown, cut the adhesive film 5 along the first cutting direction C1D1 at the cutting position to obtain Figure 15 the adhesive film block 5 as shown.

[0093] It should be noted that according to the size of the adhesive film block, at least one cutting position can be determined, and cutting along the groove corresponding to the cutting position can obtain at least one adhesive film block.

[0094] Similarly, in the embodiment of the present application, step S20 can also be implemented by using the above film strip processing mechanism. Specifically, step S20. Cut the adhesive film block along the second cutting direction, including:

[0095] S20’. Use the film strip processing mechanism to cut the adhesive film block along the second cutting direction; wherein, the second cutting direction is parallel to the length direction of the groove.

[0096] The following specifically describes how to use the film strip processing mechanism to cut the adhesive film block.

[0097] Specifically, step S20' uses a film strip processing mechanism to cut the adhesive film block along the second cutting direction, including:

[0098] S201. Refer to Figure 15 As shown, adsorb the adhesive film block 5 to the film strip processing plate 4; wherein, the length direction of the groove is parallel to the length direction or the width direction of the adhesive film block.

[0099] S202. Cut at positions corresponding to the two opposite inner walls of the adhesive film block and at least one groove to obtain at least one adhesive film strip; wherein, the width of the adhesive film strip is the same as the width W of the groove, and the length L of the groove is greater than the length of the adhesive film strip. For example, refer to Figure 15 As shown, cut at positions corresponding to the two opposite inner walls of the adhesive film block 5 and the leftmost groove 41 (i.e., cut along the Figure 15 shown second cutting directions C2D2 and C3D3) to obtain an adhesive film strip. Similarly, cutting at positions corresponding to the two opposite inner walls of the adhesive film block and other grooves can obtain multiple adhesive film strips.

[0100] In the embodiments of the present application, the width range of the adhesive film strip is [4 mm, 12 mm]. Specifically, the width of the adhesive film strip can be 4 mm, 6 mm, 8 mm, 10 mm, or 12 mm; similarly, the width range of the groove can be [4 mm, 12 mm]. Specifically, the width of the groove can be 4 mm, 6 mm, 8 mm, 10 mm, or 12 mm.

[0101] In the embodiments of the present application, when applying the film strip processing mechanism to cut the adhesive film block, the width of the groove of the film strip processing mechanism needs to be the same as the width of the adhesive film strip. In this way, after adsorbing the adhesive film block to the film strip processing plate and cutting at positions corresponding to the two opposite inner walls of the adhesive film block and at least one groove, at least one adhesive film strip can be obtained. Here, the two opposite inner walls of the groove are arranged along the length direction of the groove. The length direction of the groove is parallel to the second cutting direction.

[0102] The following provides an implementation method for step S1.

[0103] In one or more embodiments, step S1 uses a first heating process to fix the battery cell to the adhesive film strip, including:

[0104] S11. Heat the battery cell using a first heating process.

[0105] For example, the conveyor belt of the string welding machine can be pre-heated, and then the battery cell is placed on the heated belt to achieve the heating of the battery cell based on the principle of heat conduction.

[0106] S12. Fix the adhesive film tape on the front side and / or the back side of the edge of the heated cell.

[0107] Exemplarily, the film tape picking and placing mechanism 7 as shown in Figure 17 can be adopted to place the adhesive film tape 1 on the front side and / or the back side of the edge of the heated cell 2. After the adhesive film tape 1 is heated and melted, it is bonded to the cell 2. The film tape picking and placing mechanism 7 can process at least one adhesive film tape 1 simultaneously. The structure of the film tape picking and placing mechanism can be obtained with reference to the related art and will not be described in detail here.

[0108] Another implementation method of step S1 is provided below.

[0109] In one or more embodiments, in step S1, fixing the cell and the adhesive film tape by using the first heating process includes:

[0110] S011. Heat the adhesive film tape by using the first heating process;

[0111] Exemplarily, the adhesive film is heated by preheating the placing platform and then placing the adhesive film tape on the preheated placing platform. The placing platform is made of a material that does not adhere to the adhesive film tape, such as silicone or polyvinyl fluoride. The placing platform can adopt the original heating platform in the string welding machine (i.e., the heating belt for drying the sliced cells), which can improve the utilization rate of the string welding machine.

[0112] S012. Fix the heated adhesive film tape on the front side and / or the back side of the edge of the cell.

[0113] Exemplarily, the cell can be placed on the heated adhesive film tape by the chip sucking mechanism, and then the edge area of the cell is pressed to make the adhesive film tape adhere and fix to the edge of the cell.

[0114] In one or more embodiments, in step S1, the heating temperature range of the first heating process is [50°C, 120°C]. Specifically, the heating temperature of the first heating process can be 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C or 120°C; the material of the adhesive film tape is a non-pre-crosslinked material; the grammage range of the adhesive film tape is [100 g / m², 200 g / m²]. Specifically, the grammage of the adhesive film tape can be 100 g / m², 120 g / m², 140 g / m², 160 g / m², 180 g / m² or 200 g / m²; the thickness range of the adhesive film tape is [0.1 mm, 0.3 mm]. Specifically, the thickness of the adhesive film tape can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm or 0.3 mm.

[0115] It should be noted that the heating temperature range of the first heating process can refer to the heating temperature range of the cell or the heating temperature range of the film tape. Within this heating temperature range, the film tape can be melted to bond with the cell.

[0116] If the material of the film tape is a non-pre-crosslinked material and the gram weight range of the film tape is [100 g / m², 200 g / m²], the second heating process can adopt a laser welding method. This film tape does not need to use a pre-crosslinked high-temperature resistant film material, which can further reduce costs.

[0117] It should be noted that if the belt of the stringer is used to heat the film tape in step S1, in order to prevent the film tape from bonding with the belt and causing abnormal shutdown of the equipment, an air-cooling or water-cooling device can be added behind the welding light box of the stringer to reduce the temperature of the film tape and make the film tape cool rapidly, so as to avoid bonding with the belt. In addition, in order to improve the yield, a CCD (Charge-coupled Device) detection function can be added in the processes of cell loading, cutting the encapsulation film into film blocks, cutting the film blocks into film tapes, and bonding and fixing the film tape to the cell.

[0118] The embodiments of the present disclosure also provide a photovoltaic module, which is used to convert the received light energy into electrical energy. Refer to Figure 18 and Figure 19 As shown, the photovoltaic module includes: a battery string formed by using the preparation method of the battery string provided in the foregoing embodiments; the battery string includes a plurality of connected cells 2; an encapsulation film 102 for covering the surface of the battery string; and a cover plate 103 for covering the surface of the encapsulation film facing away from the battery string.

[0119] It should be noted that solar cells are electrically connected to form a plurality of battery strings, and the plurality of battery strings are electrically connected in series and / or in parallel. Since the solar cell includes segmented cells, and the segmented cells are formed after dividing the whole solar cell, thus, by means of the current drop of the segmented cells, the power loss of the photovoltaic module can be improved to enhance the photoelectric conversion efficiency of the photovoltaic module.

[0120] In one or more embodiments, refer to Figure 18 As shown, the plurality of battery strings can be electrically connected through a conductive tape 402. Figure 19Only the positional relationship between solar cells is schematically shown, that is, the electrodes of the cell wafers with the same polarity have the same arrangement direction, or in other words, the electrodes with the positive polarity of each cell wafer are arranged towards the same side, so that the conductive strips are respectively connected to different sides of two adjacent cell wafers. In some embodiments, the cell wafers can also have electrodes of different polarities facing the same side, that is, the electrodes of adjacent cell wafers are sequentially arranged in the order of the first polarity, the second polarity, and the first polarity, then the conductive strips connect two adjacent cell wafers on the same side.

[0121] In one or more embodiments, no gap is provided between the cell wafers, that is, the cell wafers overlap each other.

[0122] In one or more embodiments, the encapsulation adhesive film includes a first encapsulation layer and a second encapsulation layer. The first encapsulation layer covers one of the front or back sides of the solar cell, and the second encapsulation layer covers the other of the front or back sides of the solar cell. Specifically, at least one of the first encapsulation layer or the second encapsulation layer can be an organic encapsulation adhesive film such as a polyvinyl butyral (PVB) adhesive film, an ethylene-vinyl acetate copolymer (EVA) adhesive film, a polyolefin elastomer (POE) adhesive film, or a polyethylene terephthalate (PET) adhesive film.

[0123] In some cases, there is a demarcation line between the first encapsulation layer and the second encapsulation layer before lamination. After the lamination process, there will no longer be the concept of the first encapsulation layer and the second encapsulation layer in the formed photovoltaic module, that is, the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation adhesive film.

[0124] In one or more embodiments, the cover plate can be a cover plate with a light-transmitting function such as a glass cover plate or a plastic cover plate. Specifically, the surface of the cover plate facing the encapsulation adhesive film can be an uneven surface, so as to increase the utilization rate of incident light. The cover plate includes a first cover plate and a second cover plate. The first cover plate is opposite to the first encapsulation layer, and the second cover plate is opposite to the second encapsulation layer.

[0125] In one or more embodiments, refer to Figure 18 As shown, the cell wafers 2 in the battery string are arranged along the direction U, and the main grids of two adjacent cell wafers 2 in the battery string are staggered in the direction Y. For the photovoltaic module, by setting the main grids of two adjacent cell wafers 2 in the battery string to be staggered in the direction Y, different potentials of the photovoltaic module can be tested, thereby improving the reliability of the test results.

[0126] In one or more embodiments, the solar cell includes, but is not limited to, a PERC cell (Passivated Emitter Rear Cell), an IBC cell (Interdigitated Back Contact), a TOPCon cell (Tunnel Oxide Passivated Contact), a HIT / HJT cell (Heterojunction Technology), a thin-film solar cell, or any combination thereof. Among them, the thin-film solar cell includes, but is not limited to, a perovskite thin-film solar cell, a copper indium selenide thin-film solar cell, a gallium arsenide thin-film solar cell, and a cadmium sulfide thin-film solar cell. The tandem cell includes, but is not limited to, a perovskite cell stacked with a crystalline silicon cell, a perovskite cell stacked with a perovskite cell, and a perovskite cell stacked with a thin-film cell.

[0127] The embodiment of the present disclosure also provides a film strip processing mechanism, which is applied to the preparation method of the foregoing battery string for reference Figure 12 and Figure 13 As shown, the film strip processing mechanism includes a film strip processing plate 4, and the film strip processing plate 4 is provided with a plurality of parallel grooves 41.

[0128] In the embodiment of the present application, the groove depth of the film strip processing plate may be less than or equal to the thickness of the film strip processing plate. It should be noted that in order to facilitate the cutting knife to cut along the groove, the bottom of the groove can be hollowed out.

[0129] This film strip processing mechanism can be used to realize the cutting of the glue film. The specific usage method and related description can refer to the embodiment of the foregoing battery string preparation method, which will not be elaborated here.

[0130] In one or more embodiments, the length direction of the groove is the same as the length direction of the glue film strip of the battery string; the width of the glue film strip is the same as the width of the groove, and the length of the groove is greater than the length of the glue film strip. By setting the width of the groove, glue film strips of different widths can be cut.

[0131] This film strip processing mechanism can be used to realize the cutting of the glue film block, so as to obtain the glue film strip. The specific usage method and related description can refer to the embodiment of the foregoing battery string preparation method, which will not be elaborated here.

[0132] The film strip processing mechanism provided by the embodiment of the present application can first cut the glue film to obtain the glue film block, and then cut the glue film block to obtain the glue film strip. Of course, this film strip processing mechanism can also be applied to other scenarios that require cutting, which is not limited here. This film strip processing mechanism has the characteristics of simple implementation and strong operability.

[0133] Those of ordinary skill in the art can understand that the above embodiments are specific examples for implementing the present disclosure. In actual applications, various changes can be made to them in form and details without departing from the spirit and scope of the present disclosure. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the scope defined by the claims.

Claims

1. A method for preparing a battery string, characterized in that: include: The battery cell and the adhesive film tape are fixed by using a first heating process; wherein the adhesive film tape is arranged on the front side of the edge of the battery cell and / or on the back side of the edge of the battery cell; Arranging a plurality of the battery cells along a first direction; wherein the arrangement direction of the adhesive film tape intersects with the first direction; Arranging welding strips on adjacent battery cells along the first direction; wherein the welding strips are arranged crosswise with the adhesive film strips, and the welding strips are arranged on a side of the adhesive film strips away from the battery cells; The soldering tape is fixed to the adhesive tape and the battery cell respectively by using a second heating process.

2. The preparation method according to claim 1, characterized in that: Before the first heating process is used to fix the battery cell and the adhesive film tape, the preparation method further includes: Cutting the adhesive film along a first cutting direction to obtain an adhesive film block; wherein the first cutting direction intersects with an extension direction of the adhesive film, and a size of the adhesive film block along the extension direction of the adhesive film is the same as a size of the battery cell along the first direction; The adhesive film block is cut along a second cutting direction to obtain the adhesive film tape; wherein the second cutting direction is a length direction or a width direction of the adhesive film block.

3. The preparation method according to claim 2, characterized in that: The step of cutting the adhesive film along the first cutting direction comprises: The adhesive film is cut along a first cutting direction using a film tape processing mechanism; wherein the film tape processing mechanism comprises a film tape processing plate, and the film tape processing plate is provided with a plurality of parallel grooves; and the length direction of the grooves is parallel to the first cutting direction.

4. The preparation method according to claim 3, characterized in that: The method of cutting the adhesive film along a first cutting direction using a film strip processing mechanism includes: Adsorbing the adhesive film to the film tape processing plate; wherein the length direction of the groove intersects with the extension direction of the adhesive film; Determining a cutting position of the adhesive film according to a size of the adhesive film block, wherein the cutting position of the adhesive film corresponds to a position of at least one of the grooves; The adhesive film is cut at the cutting position along the first cutting direction to obtain the adhesive film block.

5. The preparation method according to claim 3, characterized in that: The step of cutting the adhesive film block along the second cutting direction includes: The film strip processing mechanism is used to cut the adhesive film block along the second cutting direction; wherein the second cutting direction is parallel to the length direction of the groove.

6. The preparation method according to claim 5, characterized in that: The step of cutting the adhesive film block along the second cutting direction using the film tape processing mechanism includes: Adsorbing the adhesive film block to the film tape processing plate; wherein the length direction of the groove is parallel to the length direction of the adhesive film block or the width direction of the adhesive film block; Cutting is performed at positions corresponding to two opposite inner walls of the film block and at least one of the grooves to obtain at least one of the film strips; wherein the width of the film strip is the same as the width of the groove, and the length of the groove is greater than the length of the film strip.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The method of fixing the battery cell and the adhesive film tape by using the first heating process includes: Heating the battery cell using the first heating process; The adhesive film tape is fixed on the front side of the edge of the heated battery cell and / or the back side of the edge of the heated battery cell.

8. The preparation method according to any one of claims 1 to 6, characterized in that: The method of fixing the battery cell and the adhesive film tape by using the first heating process includes: Using the first heating process to heat the adhesive film tape; The heated adhesive film tape is fixed to the front side of the edge of the battery cell and / or the back side of the edge of the battery cell.

9. The preparation method according to claim 1, characterized in that: The heating temperature range of the first heating process is [50°C, 120°C]; the material of the adhesive film tape is a non-pre-crosslinked material; the gram weight range of the adhesive film tape is [100g / m^2, 200g / m^2]; the thickness range of the adhesive film tape is [0.1mm, 0.3mm].

10. A photovoltaic module, characterized in that: include: A battery string formed by the method for preparing a battery string according to any one of claims 1 to 9; A packaging film, used to cover the surface of the battery string; The cover plate is used to cover the surface of the packaging film facing away from the battery string.

11. A film tape processing mechanism, characterized in that: Applicable to the method for preparing the battery string according to any one of claims 3 to 6; The film tape processing mechanism includes a film tape processing plate, and the film tape processing plate is provided with a plurality of parallel grooves.

12. The film tape processing mechanism according to claim 11, characterized in that: The length direction of the groove is the same as the length direction of the adhesive film tape of the battery string; the width of the adhesive film tape is the same as the width of the groove, and the length of the groove is greater than the length of the adhesive film tape.

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