A multi-piece string interconnection method

Abstract

The application discloses a multi-piece string interconnection method, and relates to the technical field of battery string production, which comprises the following steps: arranging at least two battery pieces into a battery piece string group through welding strips; connecting the first lap joint end or the second lap joint end of the battery piece string group with the second lap joint end or the first lap joint end of the previous battery piece string group in a connecting area; and making the second adhesive film and the second welding strip segment of the second lap joint end in one of the battery piece string groups adhere to the surface of the first battery piece in the first lap joint end of the other to form a continuous battery string. The second adhesive film and the second welding strip segment extending out of the battery piece are pre-laminated, and are laminated with the adjacent battery piece string group directly, so that the independent adhesive step of the adhesive film is simplified, the production efficiency is improved, and the stability of the position of the welding strip in the series connection process of the battery piece string group is ensured.

Description

Technical Field

[0001] This invention relates to the field of battery string manufacturing technology, and in particular to a method for interconnecting multiple battery cells in series. Background Technology

[0002] With the development of the photovoltaic industry, the method of bonding solar cells to welding ribbons using adhesive film has gradually become a key technology for improving the reliability of solar cell strings and saving the manufacturing cost of solar cell strings.

[0003] The adhesive film melts upon heating, achieving stable bonding between the solder ribbon and the surface of the battery cell. It then solidifies through natural cooling or forced cooling, forming a robust and highly consistent battery string connection structure.

[0004] Existing technologies mostly employ single-piece welding and series connection processes, resulting in long production cycles, low equipment utilization, and difficulty in meeting the demand for high-efficiency production capacity. At the same time, the welding strip used to connect with another battery cell needs to be precisely positioned and pre-fixed to the edge area of ​​the battery cell by a separate clamping device, which is structurally complex, and the clamping method is prone to defects such as poor welding or short circuit due to welding strip misalignment. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method for interconnecting multiple chips in series.

[0006] This application provides a method for interconnecting multiple battery cells in series, in which at least two battery cells are connected in series by a solder strip segment to form a battery cell string group. The solder strip segment includes a first solder strip segment and a second solder strip segment connected together. The battery cell string group includes a first overlapping end, a combined middle section and a second overlapping end stacked in sequence according to the battery cell connection pattern. The first overlapping end includes a first battery cell and a first solder strip segment extending from the surface of an adjacent battery cell to the surface of the first battery cell, as well as a first adhesive film attached to the first solder strip segment and the surface of the first battery cell. The combined middle section includes a second battery cell and a first solder strip segment and a second solder strip segment respectively connected to different electrode positions of the second battery cell. The second overlapping end includes a second solder strip segment extending from the surface of the second battery cell and a second adhesive film superimposed on the second solder strip segment. The first or second overlap end of the battery cell string group is connected to the second or first overlap end of the previous battery cell string group in the connection area, so that the second adhesive film and the second weld strip segment of the second overlap end in one battery cell string group are bonded to the surface of the first battery cell in the first overlap end of the other group to form a continuous battery string.

[0007] Further, connecting the first or second overlap end of the battery cell string group to the first or second overlap end of the previous battery cell string group in the connection area includes: In the case of laying the first type of battery string, the first welding strip segment in the first overlapping end of the other is disposed on the first surface of the first battery cell, and the second adhesive film and the second welding strip segment in the second overlapping end of the one type of battery cell string are bonded to the second surface of the first battery cell in the other first overlapping end that is away from the first surface. In the case of laying a second type of battery string, the first weld strip segment in the first overlap end of the other type is disposed on the first surface of the first battery cell, and the second adhesive film and the second weld strip segment in the second overlap end of the battery cell string group are alternately bonded to the first surface of the first battery cell in the first overlap end of the other type.

[0008] Further, connecting the first or second overlap end of the battery cell string group to the first or second overlap end of the previous battery cell string group in the connection area includes: The second overlapping end of the battery cell string group is stacked and connected above or below the first overlapping end of the previous battery cell string group, or... The first overlapping end of the battery cell string group is stacked and connected above or below the second overlapping end of the previous battery cell string group.

[0009] Furthermore, the combined middle section in the battery cell string group includes at least two sets, and the two sets of combined middle sections are connected in series.

[0010] Furthermore, before preparing the battery cell string group, a starting end battery cell string group is also prepared in advance. The starting end battery cell string group includes a starting end battery cell located at its second overlapping end. A second solder strip segment and a solder strip lead-out segment extending from its side are laid on the starting end battery cell. The first overlapping end of the starting end battery cell string group has the same structure as the first overlapping end of the battery cell string group and is used to align and connect with the second overlapping end of the battery cell string group.

[0011] Furthermore, after the first or second lap end of the battery cell string group is connected to the first or second lap end of the previous battery cell string group in the connection area, the process further includes: synchronously transmitting the battery cell string group and the first or second lap end of the previous battery cell string group to the subsequent work station.

[0012] Furthermore, when connecting the first or second overlapping end of the battery cell string group to the first or second overlapping end of the previous battery cell string group in the connection area, the method further includes: applying a preset pressure and heating synchronously to the connection area between the two battery cell string groups, or applying a preset pressure and heating synchronously to the middle section of the combination of the connection area and the battery cell string group.

[0013] Furthermore, the tail end of the second solder strip segment in the battery cell string located in the connection area is limited and fixed.

[0014] Furthermore, the second adhesive film in the battery cell string is bent at the edge near the end of the second solder strip segment. After the first or second overlapping end of the battery cell string group is connected to the first or second overlapping end of the previous battery cell string group in the connection area, the method further includes: smoothing the bent surface of the second adhesive film and forming a covering structure with the tail end of the second welding strip segment.

[0015] Furthermore, connecting at least two solar cells in series to form a solar cell string includes: simultaneously laying multiple solar cells at intervals; synchronously placing multiple sets of solder ribbon segments and matching first adhesive films on the top of the multiple solar cells; each first adhesive film covering the surface of the solar cell with a first solder ribbon segment of the solder ribbon segment; and the second solder ribbon segment of the solder ribbon segment extending out of one side of the solar cell and stacked with a second adhesive film to form multiple solar cell units. Multiple solar cell units are synchronously stacked into solar cell strings, such that the second solder strip and the second adhesive film of one of the adjacent solar cell units are stacked on the surface of the solar cell in another solar cell unit.

[0016] Furthermore, when placing multiple sets of solder ribbon segments and matching first adhesive films on the upper part of multiple battery cells, the method includes: heating and pressing the first adhesive film to bond and fix the first solder ribbon segments to the connection point of the battery cells.

[0017] Furthermore, while simultaneously stacking multiple battery cell units into the battery cell string group, the process includes: moving the battery cell unit located at the second overlapping end of the battery cell string group to the connection area, extending the second solder strip segment and the second adhesive film therein to the surface of the first battery cell at the first overlapping end of the previous battery cell string group, and simultaneously applying pressure and heating to the second adhesive film in the multiple battery cells and the second adhesive film extending to the connection area.

[0018] The beneficial effects of this invention on battery strings are as follows: By pre-bonding the solder ribbon on the first electrode of the battery cell to the first adhesive film, and then stacking the second solder ribbon segment extending from the side of the battery cell with the second adhesive film of the adjacent battery cell unit, a pre-connected battery cell string is achieved. The process of preparing the battery cell string simultaneously stacks multiple battery cells, significantly improving the stringing efficiency. Furthermore, by pre-stacking the second adhesive film with the second solder ribbon segment extending from the battery cell, it is directly stacked with the adjacent battery cell string to form a series connection structure. The second adhesive film used to bond the second solder ribbon segment does not require separate additional laying, reducing process steps, lowering process complexity, and eliminating the step of separately bonding the second solder ribbon segment of another battery cell in the traditional process, reducing problems such as incomplete soldering and misalignment caused by positioning deviations. This also improves stringing efficiency and connection reliability. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of the battery cell string group proposed in this invention; Figure 2 This is a schematic diagram of the first step in the first battery string series connection method proposed in this invention; Figure 3 This is a schematic diagram of the second step of the first battery string series connection method proposed in this invention; Figure 4 This is a schematic diagram of the third step in the first battery string series connection method proposed in this invention; Figure 5 This is a schematic diagram of the fourth step in the first battery string series connection method proposed in this invention; Figure 6 This is a schematic diagram of another battery cell string structure proposed in this invention; Figure 7 This is a schematic diagram of the structure of the starting-end battery cell string group proposed in this invention; Figure 8 This is a schematic diagram illustrating the steps involved in fabricating the battery cell unit proposed in this invention.

[0021] The attached figures are labeled as follows: 10. Cell string assembly; 1. First cell; 12. Second cell; 2. First adhesive film; 3. Welding strip segment; 31. First welding strip segment; 32. Second welding strip segment; 4. Second adhesive film; 20. Cell unit; a. First overlapping end; b. Second overlapping end; c. Welding strip lead-out segment; 11. Starting cell. Detailed Implementation

[0022] The embodiments of this application are described in detail below. Examples of the above embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0023] It should be understood that the following embodiments do not limit the execution order of the steps in the method protected by this application. The steps of the method of this application can be executed in any possible order and in a cyclic manner without contradicting each other.

[0024] In the description of this application, it should be understood that the terms "length", "width", "thickness", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "front", "back", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0026] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0027] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0028] In existing technologies, battery strings with adhesive film bonding include multiple battery cells, with adjacent cells connected in series via solder ribbon segments. The adhesive film covers the front or back of the battery cells for encapsulation and protection. In specific implementations, the adhesive film in the battery string includes a first adhesive film 2 and a second adhesive film 4 simultaneously bonded to a first solder ribbon segment 31 of one set of solder ribbon segments 3 and a second solder ribbon segment 32 of the other set located on one side of the battery cell. The first solder ribbon segment 31 and the second solder ribbon segment 32 are connected as a set of solder ribbon segments 3, and each set of solder ribbon segments 3 is electrically connected to the two electrodes of two adjacent battery cells. Alternatively, the adhesive film includes a first adhesive film 2 and a second adhesive film 4 bonded to the two surfaces of the battery cell to fix the relative positions of the first solder ribbon segment 31 of one set and the second solder ribbon segment 32 of the other set on the two surfaces of the battery cell.

[0029] This application proposes a method for interconnecting multiple chips in series, such as... Figure 1 , Figure 2 As shown, it includes: connecting at least two battery cells in series through a welding strip 3 to form a battery cell string group 10. The welding strip 3 includes a first welding strip 31 and a second welding strip 32 connected together. The battery cell string group 10 includes a first overlapping end a, a combined middle section and a second overlapping end b stacked in sequence according to the battery cell connection rule. The first overlapping end a of the battery cell string 10 includes a first battery cell 1 and a first solder strip segment 31 extending from the surface of an adjacent battery cell to the surface of the first battery cell 1, and a first adhesive film 2 attached to the first solder strip segment 31 and the surface of the first battery cell 1. The second overlapping end b of the battery cell string 10 includes a second battery cell 12 and a second solder strip segment 32 extending from the surface of the second battery cell 12, and a second adhesive film 4 attached to the second solder strip segment 32. The first overlapping end a or the second overlapping end b of the battery cell string group 10 is connected to the first overlapping end a or the second overlapping end b of the previous battery cell string group 10 in the connection area. The first overlapping end a of the previous battery cell string group 10 is the same as that of the battery cell string group 10, both including: a second battery cell 12 and a first solder strip segment 31 extending from the surface of the adjacent battery cell to the surface of the second battery cell 12, and a first adhesive film 2 attached to the surface of the first solder strip segment 31 and the surface of the second battery cell 12. The second overlapping end b of the current battery cell string group 10 is connected to the first overlapping end a of the previous battery cell string group 10, or the first overlapping end a of the current battery cell string group 10 is connected to the second overlapping end b of the current battery cell string group 10, so that the second adhesive film 4 and the second welding strip 32 of the second overlapping end b of one battery cell string group 10 are bonded to the surface of the first battery cell 1 in the first overlapping end a of the other, forming an electrical connection and achieving mechanical fixation at the same time, ensuring stable series connection between battery strings.

[0030] The above method enables rapid alignment and bonding between battery strings, reducing the number of independent film application and positioning steps required in traditional processes and improving production efficiency. Simultaneously, the process of connecting at least two battery cells in series with other battery string groups 10 is simplified into a continuous operation, improving overall stringing efficiency and yield. Furthermore, the battery string group 10 includes the simultaneous sequential connection of multiple battery cells, with solder ribbons pre-fixed on the surface of the battery cells using a first adhesive film 2. This ensures the stability of the solder ribbon position during subsequent stringing processes, effectively preventing incomplete soldering or short circuits caused by solder ribbon misalignment and improving module reliability.

[0031] Existing battery string types include a first type where the positive and negative electrodes of the battery cells are located on two opposing surfaces of the battery cells, and the positive and negative electrode surfaces of adjacent battery cells are connected in series by solder ribbons; and a second type where the positive and negative electrode areas of the battery cells are located on the same surface of the battery cells, and adjacent battery cells are connected in series by solder ribbons with staggered ends.

[0032] In a suitable embodiment, connecting the first overlapping end a or the second overlapping end b of the battery cell string group 10 to the first overlapping end a or the second overlapping end b of the previous battery cell string group 10 in the connection area includes: In the case of laying the first type of battery string, the first welding strip 31 in the first overlapping end a of the other is disposed on the first surface of the first battery cell 1, wherein the second adhesive film 4 and the second welding strip 32 in the second overlapping end b of one battery cell string group 10 are bonded to the second surface of the first battery cell 1 in the other first overlapping end a that is away from the first surface. In the case of laying the second type of battery string, the first welding strip 31 in the first overlapping end a of the other is disposed on the first surface of the first battery cell 1, wherein the second adhesive film 4 and the second welding strip 32 in the second overlapping end b of one battery cell string group 10 are alternately bonded to the first surface of the first battery cell 1 in the same direction in the other first overlapping end a.

[0033] Specifically, connecting the first overlapping end a or the second overlapping end b of the battery cell string group 10 to the first overlapping end a or the second overlapping end b of the previous battery cell string group 10 in the connection area includes: Reference Figure 2 , Figure 3 As shown, the second overlapping end b of the battery cell string group 10 is stacked and connected above or below the first overlapping end a of the previous battery cell string group 10. In the first battery string laying configuration, when the first weld strip 31 on the first overlapping end a of the current group of battery cell strings 10 is located on the lower surface of the battery cell, the second weld strip 32 on the second overlapping end b of the battery cell string 10 overlaps with the upper surface of the battery cell, and the second adhesive film 4 is stacked and attached to the upper surface of the second weld strip 32; when the first weld strip 31 on the first overlapping end a of the current group of battery cell strings 10 is located on the upper surface of the battery cell, the second weld strip 32 on the second overlapping end b of the battery cell string 10 overlaps with the lower surface of the battery cell, and the second adhesive film 4 is stacked and attached to the lower surface of the second weld strip 32.

[0034] In the second battery string arrangement, when the first weld strip 31 on the first overlapping end a of the current battery cell string 10 is located on the lower surface of the battery cell, the first weld strip 31 is bonded to the surface of the battery cell by the first adhesive film 2. The second weld strip 32 on the second overlapping end b of the battery cell string 10 overlaps from the lower surface of the battery cell. The second adhesive film 4 is stacked and attached to the lower surface of the second weld strip 32 and is alternately connected to the first weld strip 31 and the first adhesive film 2 on the same surface of the battery cell in different electrode areas on the same surface of the battery cell. When the first weld strip 31 on the first overlapping end a of the current battery cell string 10 is located on the upper surface of the battery cell, the second weld strip 32 on the second overlapping end b of the battery cell string 10 overlaps from the upper surface of the battery cell. The second adhesive film 4 is stacked and attached to the upper surface of the second weld strip 32 and is alternately connected to the first weld strip 31 and the first adhesive film 2 on the same surface of the battery cell in different electrode areas on the same surface of the battery cell.

[0035] Or, refer to Figure 4 , Figure 5 As shown, the first overlapping end a of the battery cell string group 10 is stacked and connected above or below the second overlapping end b of the previous battery cell string group 10.

[0036] In one battery string arrangement, when the second weld strip 32 on the second overlapping end b of the current group of battery cells 10 is located on the lower surface of the battery cell, the first weld strip 31 on the first overlapping end a of the battery cell 10 overlaps with the upper surface of the battery cell, and the second adhesive film 4 is stacked and attached to the upper surface of the second weld strip 32; when the first weld strip 31 on the first overlapping end a of the current group of battery cells 10 is located on the upper surface of the battery cell, the second weld strip 32 on the second overlapping end b of the battery cell 10 overlaps with the lower surface of the battery cell, and the second adhesive film 4 is stacked and attached to the lower surface of the second weld strip 32.

[0037] In another battery string arrangement, when the first weld strip 31 on the first overlapping end a of the current battery cell string 10 is located on the lower surface of the battery cell, the first weld strip 31 is bonded to the surface of the battery cell by the first adhesive film 2. The second weld strip 32 on the second overlapping end b of the battery cell string 10 overlaps from the lower surface of the battery cell. The second adhesive film 4 is stacked and attached to the lower surface of the second weld strip 32 and is alternately connected to the first weld strip 31 and the first adhesive film 2 on the same surface of the battery cell in different electrode areas on the same surface of the battery cell. When the first weld strip 31 on the first overlapping end a of the current battery cell string 10 is located on the upper surface of the battery cell, the second weld strip 32 on the second overlapping end b of the battery cell string 10 overlaps from the upper surface of the battery cell. The second adhesive film 4 is stacked and attached to the upper surface of the second weld strip 32 and is alternately connected to the first weld strip 31 and the first adhesive film 2 on the same surface of the battery cell in different electrode areas on the same surface of the battery cell.

[0038] For two sets of welding ribbon segments 3 that are simultaneously bonded to the same side by adhesive film, the two sets of welding ribbon segments 3 that are staggered on the same surface of the battery cell are positioned and fixed by the first adhesive film 2 or the second adhesive film 4. For the first adhesive film 2 and the second adhesive film 4 of the two sets of welding ribbon segments 3 that are bonded to the two surfaces of the battery cell respectively, the two sets of welding ribbon segments 3 are fixed to the front and back of the battery cell respectively. The first adhesive film 2 bonds part of the first welding ribbon segment 31 of one set of welding ribbons to the front of the battery cell, and the second adhesive film 4 bonds part of the second welding ribbon segment 32 of the other set of welding ribbons to the back of the battery cell, thereby achieving independent positioning and fixing of the double-sided welding ribbons.

[0039] To improve the series connection efficiency of battery strings, such as Figure 3 As shown, the battery cell string group 10 in this application also includes a combined middle section connected in series to the first overlapping end a and the second overlapping end b of the battery cell string group 10. Both ends of the combined middle section are provided with a solder strip segment 3 and a corresponding adhesive film. The middle section battery cell string group 10 includes at least one middle section battery cell, and a first solder strip segment 31 and a second solder strip segment 32 laid on different electrode positions on the surface of the middle section battery cell. The first solder strip segment 31 and the second solder strip segment 32 are respectively fixed to two different electrode positions on one or both sides of the battery cell by the first adhesive film 2 and the second adhesive film 4.

[0040] When the first adhesive film 2 and the second adhesive film 4 are both fixed on the same surface of the battery cell, the first adhesive film 2 and the second adhesive film 4 are respectively bonded to the first welding strip segment 31 and the second welding strip segment 32 of the middle section of the battery cell at intervals.

[0041] In this configuration, multiple solar cells can be connected in series simultaneously in the middle section of the solar cell string group 10. These connected solar cells are then connected to adjacent solar cell string groups 10 to form a continuous circuit connection. This improves the efficiency of solar cell string connection and production.

[0042] Before fabricating the battery cell string group 10, the process also includes pre-fabricating the starting end battery cell string group 11, such as... Figure 4 As shown, the starting end battery cell 11 string group 10 includes a starting end battery cell 11 located at its second overlapping end b. The starting end battery cell 11 is provided with a second solder ribbon segment 32 and a solder ribbon lead-out segment c extending from its side. The other end of the solder ribbon lead-out segment c is fixed to the surface of the starting end battery cell 11 by a first adhesive film 2. The first overlapping end a of the starting end battery cell 11 string group 10 has the same structure as the first overlapping end a of the battery cell string group 10, both including a first battery cell 1 and a first solder ribbon segment 31 and a first adhesive film 2. The first solder ribbon segment 31 of the starting end battery cell 11 string group 10 is used to achieve electrical connection with the second solder ribbon segment 32 of the second overlapping end b of the subsequent battery cell string group 10. The second solder ribbon segment 32 of the second overlapping end b of the subsequent battery cell string group 10 is connected to the surface of the first battery cell 1 of the first overlapping end a of the starting end battery cell 11 string group 10 by a second adhesive film 4 to achieve electrical conduction, thereby completing the series connection between battery strings.

[0043] In a specific embodiment, after connecting the second overlapping end b of the battery cell string group 10 with the first overlapping end a of the previous battery cell string group 10, the method further includes applying a preset pressure to the connection area between the two battery cell string groups 10 and heating and curing it, so that the second adhesive film 4 is fully fused in the connection area, ensuring that the solder strip 3 and the surface of the battery cell form a stable and reliable electrical connection.

[0044] During the heating and curing process, uniform pressure is applied to both sides of the connection area through other pressing structures. The pressure presses the second adhesive film 4 and the second welding strip 32 of the connection area onto the surface of the battery cell. At the same time, the heating element precisely controls the temperature of the connection area, so that the second adhesive film 4 is firmly bonded to the surface of the battery cell.

[0045] The tail end of the second solder strip segment 32 in the cell string 10 located in the connection area is clamped and positioned. While clamped, the tail end of the second solder strip segment 32 completes an electrical connection with the conductive area on the surface of the first cell 1 at the first overlapping end a of the preceding cell string 10, ensuring that the solder strip position does not shift during the bonding process of the second adhesive film 4, thereby guaranteeing welding accuracy and connection reliability. The clamping structure is released after heating and curing to avoid interference with subsequent processes. The entire connection process is completed in automated equipment, ensuring precise control of pressure, temperature, and time parameters, improving the overall yield and consistency of the cell string.

[0046] To improve the bonding and positioning accuracy of the adhesive film to the welding strip 3, the second adhesive film 4 in the cell string 10 is bent downward at the edge near the tail end of the second welding strip 32. After the second overlapping end b of the cell string 10 is joined and bonded to the first overlapping end a of the previous cell string 10 in the connection area, the edge of the downwardly bent second adhesive film 4 is gradually flattened and attached to the surface of the first cell 1 at the first overlapping end a of the previous cell string 10. The bent part of the second adhesive film 4 forms a covering structure with the tail end of the welding strip 3, effectively covering and fixing the second welding strip 32 laid on the surface of the cell, effectively preventing the welding strip 3 from shifting or lifting during the connection process, and ensuring the stability and reliability of the electrical connection.

[0047] Reference Figure 5 As shown, connecting at least two battery cells in series to form a battery cell string 10 includes: simultaneously laying multiple battery cells at intervals; synchronously placing multiple solder ribbon segments 3 and matching first adhesive films 2 on the upper part of the multiple battery cells; each first adhesive film 2 covers the first solder ribbon segment 31 of the solder ribbon segment 3 on the surface of the battery cell; the second solder ribbon segment 32 of the solder ribbon segment 3 extends out of the edge of the battery cell; the extended second solder ribbon segment 32 covers and adheres to the second adhesive film 4 to form multiple battery cell units 20; and then connecting the multiple battery cell units 20 in series to form a battery cell string 10. During the stacking process, the second solder ribbon segment 32 of one of the adjacent battery cell units 20 is precisely aligned with the conductive area on the surface of the battery cell in the other.

[0048] In order to more clearly describe the method of this application, the battery cell located at the first overlapping end a of the battery cell string group 10 in the multiple battery cell units 20 connected in series is regarded as the first battery cell 1, the battery cell located at the second overlapping end b of the battery cell string group 10 is regarded as the second battery cell 12, and the battery cell connected in series between the first battery cell 1 and the second battery cell 12 is the middle section battery cell.

[0049] Specifically, during stacking, the second solder strip 32 and the second adhesive film 4 in one adjacent cell unit 20 extend to the bottom of the cell in another adjacent cell unit 20. The second solder strip 32 extending to the bottom of the cell contacts the conductive area of ​​the surface of the bottom of the cell with the second adhesive film 4. By heating and pressurizing, the second adhesive film 4 bonds the second solder strip 32 to the bottom surface of the cell, or the bottom bonding is not performed and only the top electrical connection is achieved. The second adhesive film 4 is cured and connected to the bottom surface of the cell in the connection area by the cell string group 10. At the same time, the connection is... The second adhesive film 4 in the region is connected to the conductive area on the surface of the first battery cell 1 at the first overlapping end a of the previous battery cell string 10 by heating and curing. This completes the synchronous bonding and curing of the second adhesive film 4 in the battery cell string 10 and the conductive area on the surface of the first battery cell 1 at the first overlapping end a of the previous battery cell string 10 in one go. This achieves continuous electrical connection and structural fixation of multiple welding strips, improves the connection efficiency and interface stability between strings, reduces the problem of increased resistance caused by welding strip misalignment or poor contact, and further optimizes the overall electrical performance output of the battery string.

[0050] The process of placing multiple sets of weld ribbon segments 3 and matching first adhesive films 2 on top of multiple solar cells includes: heating and pressing the connection points between the first adhesive film 2 and the weld ribbons and solar cells to bond and fix the first weld ribbon segments 31. The bonded first weld ribbon segments 31 are firmly connected to the surface of the solar cells, ensuring that no relative displacement occurs during subsequent transmission and series connection. The second weld ribbon segment 32 connected to the first weld ribbon segment 31 remains suspended and extended. When adjacent solar cell units 20 are connected, it accurately falls into the conductive area of ​​the next solar cell surface. It is covered by the second adhesive film 4 and pressed and fixed to the surface of the solar cell in the connection area or before the connection area, realizing continuous series connection.

[0051] To improve the production efficiency and welding accuracy of battery strings, it is preferable to simultaneously heat and cure the conductive areas of multiple second adhesive films 4 in the battery cell string group 10 with the adjacent battery cell unit 20 and with the first overlapping end a of the previous battery cell string group 10 when the connection area is docked with the first overlapping end a of the previous battery cell string group 10.

[0052] While simultaneously stacking multiple battery cell units 20, the battery cell unit 20 closest to the second overlap end b of the battery cell string 10 is moved to the connection area, and the second solder strip segment 32 and the second adhesive film 4 therein are extended to the surface of the first battery cell 1 at the first overlap end a of the previous battery cell string 10. At the same time, pressure is applied and heated to the second adhesive film 4 in the multiple battery cells and the second adhesive film 4 extending to the connection area.

[0053] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0054] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for interconnecting multiple chips in series, characterized in that, include: At least two solar cells are connected in series by a welding strip to form a solar cell string group. The welding strip includes a first welding strip and a second welding strip connected together. The solar cell string group includes a first overlapping end, a combined middle section and a second overlapping end stacked in sequence according to the solar cell connection pattern. The first overlapping end includes a first battery cell and a first solder strip segment extending from the surface of an adjacent battery cell to the surface of the first battery cell, as well as a first adhesive film attached to the first solder strip segment and the surface of the first battery cell. The combined middle section includes a second battery cell and a first solder strip segment and a second solder strip segment respectively connected to different electrode positions of the second battery cell. The second overlapping end includes a second solder strip segment extending from the surface of the second battery cell and a second adhesive film superimposed on the second solder strip segment. The first or second overlap end of the battery cell string group is connected to the second or first overlap end of the previous battery cell string group in the connection area, so that the second adhesive film and the second weld strip segment of the second overlap end in one battery cell string group are bonded to the surface of the first battery cell in the first overlap end of the other group to form a continuous battery string.

2. The multi-chip serial interconnection method according to claim 1, characterized in that, Connecting the first or second overlapping end of the battery cell string group to the first or second overlapping end of the previous battery cell string group in the connection area includes: In the case of laying the first type of battery string, the first welding strip segment in the first overlapping end of the other is disposed on the first surface of the first battery cell, and the second adhesive film and the second welding strip segment in the second overlapping end of the one type of battery cell string are bonded to the second surface of the first battery cell in the other first overlapping end that is away from the first surface. In the case of laying a second type of battery string, the first weld strip segment in the first overlap end of the other type is disposed on the first surface of the first battery cell, and the second adhesive film and the second weld strip segment in the second overlap end of the battery cell string group are alternately bonded to the first surface of the first battery cell in the first overlap end of the other type.

3. The multi-chip serial interconnection method according to claim 1, characterized in that, Connecting the first or second overlapping end of the battery cell string group to the first or second overlapping end of the previous battery cell string group in the connection area includes: The second overlapping end of the battery cell string group is stacked and connected above or below the first overlapping end of the previous battery cell string group, or... The first overlapping end of the battery cell string group is stacked and connected above or below the second overlapping end of the previous battery cell string group.

4. The multi-chip serial interconnection method according to claim 1, characterized in that, The combined middle section in the battery cell string group includes at least two groups, and the two groups of combined middle sections are connected in series.

5. The multi-chip serial interconnection method according to claim 1, characterized in that, Before preparing the battery cell string group, a starting end battery cell string group is also prepared in advance. The starting end battery cell string group includes a starting end battery cell located at its second overlapping end. A second solder strip segment and a solder strip lead-out segment extending from its side are laid on the starting end battery cell. The first overlapping end of the starting end battery cell string group has the same structure as the first overlapping end of the battery cell string group and is used to align and connect with the second overlapping end of the battery cell string group.

6. The multi-chip serial interconnection method according to claim 1, characterized in that, After the first or second lap end of the battery cell string group is connected to the first or second lap end of the previous battery cell string group in the connection area, the process further includes: synchronously transmitting the battery cell string group and the first or second lap end of the previous battery cell string group to the subsequent work station.

7. The multi-chip serial interconnection method according to claim 1, characterized in that, When the first or second overlapping end of the battery cell string group is connected to the first or second overlapping end of the previous battery cell string group in the connection area, the method further includes: applying a preset pressure and heating synchronously to the connection area between the two battery cell string groups, or applying a preset pressure and heating synchronously to the middle section of the combination of the connection area and the battery cell string group.

8. The multi-chip serial interconnection method according to claim 1, characterized in that, The tail end of the second solder strip segment in the battery cell string located in the connection area is limited and fixed.

9. The multi-chip serial interconnection method according to claim 8, characterized in that, The second adhesive film in the battery cell string is bent at the edge near the end of the second solder strip segment. After the first or second overlapping end of the battery cell string group is connected to the first or second overlapping end of the previous battery cell string group in the connection area, the method further includes: smoothing the bent surface of the second adhesive film and forming a covering structure with the tail end of the second welding strip segment.

10. The multi-chip serial interconnection method according to claim 9, characterized in that, Connecting at least two solar cells in series to form a solar cell string includes: simultaneously laying multiple solar cells at intervals; synchronously placing multiple sets of solder ribbon segments and matching first adhesive films on the top of the multiple solar cells; each first adhesive film covering the surface of the solar cell with a first solder ribbon segment of the solder ribbon segment; and the second solder ribbon segment of the solder ribbon segment extending out of one side of the solar cell and stacked with a second adhesive film to form multiple solar cell units. Multiple solar cell units are synchronously stacked into solar cell strings, such that the second solder strip and the second adhesive film of one of the adjacent solar cell units are stacked on the surface of the solar cell in another solar cell unit.

11. The multi-chip serial interconnection method according to claim 10, characterized in that, When placing multiple sets of solder ribbon segments and matching first adhesive films on the upper part of multiple battery cells, the method includes: heating and pressing the first adhesive film to bond and fix the first solder ribbon segments to the connection point of the battery cells.

12. The multi-chip serial interconnection method according to claim 10, characterized in that, When multiple battery cell units are simultaneously stacked into the battery cell string group, the process includes: moving the battery cell unit located at the second overlap end of the battery cell string group to the connection area, extending the second solder strip segment and the second adhesive film therein to the surface of the first battery cell at the first overlap end of the previous battery cell string group, and simultaneously applying pressure and heating to the second adhesive film in the multiple battery cells and the second adhesive film extending to the connection area.

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