Heterojunction battery interconnection welding method and battery assembly

Abstract

The invention belongs to the technical field of battery welding, and discloses a heterojunction battery interconnection welding method and a battery assembly. Coating a conductive adhesive on the welding bracket; welding a plurality of cleaned battery pieces, laying the battery pieces on a welding bracket, and heating, curing and welding to form a battery string; and the adjacent battery strings are connected with the welding bracket through the welding strips to form the heterojunction battery. According to the interconnection welding method for the heterojunction battery, through a series of elaborate design and process control, the problem that the battery piece is possibly cracked due to stress generated by external force impact, subfissure or temperature difference shrinkage in the welding process is effectively solved, so that the electrical property and the photoelectric conversion efficiency of the battery piece are remarkably improved; and the quality and the reliability of the battery assembly are ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery welding, and in particular relates to a heterojunction battery interconnection welding method and a battery assembly. Background Art

[0002] In the precision manufacturing process of solar cell modules, a crucial step is to carefully assemble individual cells into cell strings through advanced ribbon welding technology or innovative shingling technology. In this process, the ribbon plays a key role in connecting and conducting current. It not only ensures a stable connection between the cells, but also optimizes the current collection and transmission path. The ribbon, professionally known as tinned copper ribbon or tin-coated copper ribbon, is further subdivided into bus ribbons and interconnecting strips according to its different functions. The bus ribbon is mainly responsible for collecting and conducting the current generated in the cell string, while the interconnecting strip is used for electrical connection between cell strings or between cell strings and the frame of the module. The two work together to improve the overall performance of the battery module.

[0003] However, in the actual welding process, the battery cells face multiple challenges, especially in the high-temperature and delicate operation of welding. Since the battery cell material is fragile, if it is subjected to improper external force impact during welding, such as mechanical vibration or human error, it is very easy to cause its structure to be damaged. In addition, the tiny cracks (hidden cracks) that may exist inside the battery cell may expand due to thermal stress during high-temperature welding, and even directly cause splitting. The material shrinkage caused by temperature difference is also a factor that cannot be ignored. It will generate additional stress inside the battery cell, further increasing the risk of splitting.

[0004] Once the cracking occurs, the consequences are extremely serious. It not only directly destroys the physical integrity of the cell, but also significantly affects the electrical performance of the cell, including reducing key parameters such as open circuit voltage, short circuit current and fill factor, thereby significantly weakening the photoelectric conversion efficiency of the solar cell module. This means that even under ideal lighting conditions, the module cannot efficiently convert light energy into electrical energy, which seriously restricts the overall output power and economic benefits of the solar cell system. Therefore, in the production process of solar cell modules, taking effective measures to prevent and reduce the cracking phenomenon during the welding process is of vital importance to ensure product quality, improve system performance and promote the sustainable development of the solar industry. Summary of the invention

[0005] The object of the present invention is to provide a heterojunction battery interconnection welding method and a battery assembly to solve the above-mentioned problems.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A heterojunction battery interconnection welding method, comprising: Clean the battery cells; Apply conductive glue on the welding bracket; Welding several cleaned battery cells and laying them on a welding bracket, heating and curing the welding to form a battery string; Adjacent battery strings are connected by welding brackets through welding ribbons to form heterojunction batteries.

[0007] Furthermore, when cleaning the battery cell, a cleaning solution is used to clean the surface of the battery cell, and then an antioxidant is sprayed.

[0008] Furthermore, the welding bracket is a triangular frame structure.

[0009] Furthermore, the welding bracket includes two hinged edges and a movable edge, one end of the two hinged edges is hinged, and the movable edge is connected to the other end of the two hinged edges by clamping.

[0010] Furthermore, the height of the welding bracket matches the height of the battery string, and the width of the moving side of the welding bracket matches the width of the battery string.

[0011] Furthermore, the conductive adhesive completely covers the entire welding bracket.

[0012] Furthermore, several adjacent battery strings are welded to a welding bracket via welding strips and packaged into a heterojunction battery assembly.

[0013] Furthermore, the cleaned battery cells are welded using shingling technology.

[0014] Furthermore, the welding heating temperature is less than 200°C.

[0015] Furthermore, a battery assembly is manufactured using the heterojunction battery interconnection welding method.

[0016] Compared with the prior art, the present invention has the following technical effects: The present invention cleans the surface of the battery cell with a cleaning solution and sprays an antioxidant, which helps to remove impurities and pollutants on the surface of the battery cell and reduce interface barriers during welding. At the same time, the antioxidant can protect the battery cell from oxidation in subsequent processing, indirectly improving the welding quality and stability of the battery cell and reducing the risk of poor welding and cracking due to surface contamination.

[0017] The use of the conductive adhesive of the present invention enhances the adhesion and conductivity between the battery cell and the welding bracket, helps to evenly distribute the thermal stress and mechanical stress during the welding process, reduces the external force impact directly acting on the battery cell, and thus reduces the possibility of cracking.

[0018] The present invention adopts a welding bracket with a triangular frame structure, as well as a specific hinge and movable edge design, which provides better stability and support, ensures that the battery cell will not be subjected to additional stress due to deformation or displacement of the bracket during the welding process, and helps to maintain the integrity of the battery cell.

[0019] The height of the welding bracket of the present invention matches the height of the battery string, and the width of the moving edge matches the width of the battery string. This design ensures accurate positioning and stable support of the battery cells during the welding process, reducing stress concentration and the risk of cracking caused by size mismatch.

[0020] The conductive adhesive of the present invention completely covers the entire welding bracket, further enhancing the bonding force between the bracket and the battery cell, while also helping to evenly transfer heat, reduce shrinkage stress caused by temperature differences, and protect the battery cell from cracking.

[0021] The present invention adopts shingling technology to weld battery cells, which can reduce the number of welding points, thereby reducing the thermal stress and mechanical stress generated during the welding process. At the same time, the shingling structure itself also helps to disperse the stress and reduce the occurrence of cracks.

[0022] The welding heating temperature of the present invention is less than 200° C. This control measure effectively reduces the thermal stress during the welding process and reduces the risk of deformation and rupture of the battery cell caused by high temperature.

[0023] In summary, this heterojunction battery interconnection welding method effectively solves the problem of battery cells being broken due to stress caused by external force impact, hidden cracks or temperature difference shrinkage during welding through a series of careful designs and process controls, thereby significantly improving the electrical performance and photoelectric conversion efficiency of the battery cells and ensuring the quality and reliability of the battery components. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0027] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0028] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0029] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0030] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0031] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0032] Example 1, please refer to Figure 1 The present invention provides a heterojunction battery interconnection welding method, comprising: Clean the battery cells; Apply conductive glue on the welding bracket; Welding several cleaned battery cells and laying them on a welding bracket, heating and curing the welding to form a battery string; Adjacent battery strings are connected by welding brackets through welding ribbons to form heterojunction batteries.

[0033] The following is an expansion of a detailed embodiment of the heterojunction battery interconnection welding method: This heterojunction battery interconnection welding method effectively solves the problem of battery cells being broken due to stress caused by external force impact, hidden cracks or temperature difference shrinkage during the welding process through a series of careful designs and process controls, thereby significantly improving the electrical performance and photoelectric conversion efficiency of the battery cells and ensuring the quality and reliability of the battery components.

[0034] Embodiment 2, the present invention provides a heterojunction battery interconnection welding method, specifically comprising: 1. Preparation Battery cleaning: Choose an efficient cleaning solution that has good dissolving ability for dirt on the surface of the battery cells and will not corrode or damage the battery cells.

[0035] Soak the battery cell in cleaning solution and use an ultrasonic cleaner to clean it to ensure that dust, grease, fingerprints and other contaminants on the surface of the battery cell are completely removed.

[0036] After cleaning, rinse thoroughly with deionized water to ensure no residue remains.

[0037] Subsequently, a layer of antioxidant is evenly sprayed on the surface of the battery cell to form a protective film to prevent the battery cell from being oxidized during subsequent processing.

[0038] Welding bracket preparation: Use high-strength, high-temperature resistant materials such as stainless steel or titanium alloy to make the welding bracket.

[0039] The welded bracket is designed as a triangular frame structure to improve stability and load-bearing capacity.

[0040] The bracket comprises two hinged sides and a movable side, one end of the hinged side is connected by a hinge, and the movable side is connected to the other ends of the two hinged sides by a clamping device, so as to facilitate the adjustment of the shape and size of the bracket.

[0041] Make sure that the height of the welding bracket matches the height of the battery string and the width of the moving edge matches the width of the battery string to ensure that the battery cells are firmly laid on the bracket.

[0042] Conductive adhesive coating: Choose a conductive adhesive with high conductivity and good adhesion.

[0043] Use an automatic glue coating machine to evenly apply the conductive glue on the welding bracket to ensure that the conductive glue completely covers the entire bracket surface without omissions and bubbles.

[0044] 2. Welding stage Battery welding: The cleaned and dried battery cells are placed on a welding bracket coated with conductive glue according to a predetermined arrangement.

[0045] The shingled technology is used, that is, the edges of the battery cells are partially overlapped to increase the contact area and stability between the battery cells.

[0046] Use precision welding equipment, such as laser welders or ultrasonic welders, to weld the cells. During the welding process, the welding temperature and welding time should be strictly controlled to avoid thermal damage to the cells.

[0047] Heat curing: The welded cells and the welding bracket are placed in a heating furnace for heating and curing. The heating temperature should be controlled within a certain range, usually less than 200°C, to avoid excessive thermal stress on the cells.

[0048] The curing time depends on the properties of the conductive adhesive and the material of the welding bracket to ensure that the conductive adhesive is completely cured to form a strong bond.

[0049] Battery string connection: The cured battery string is taken out of the heating furnace and cooled to room temperature.

[0050] Use welding ribbons to connect adjacent battery strings to form heterojunction batteries. The welding ribbons should be made of materials and specifications that match the battery cells to ensure good electrical conductivity and mechanical strength.

[0051] 3. Packaging stage Component packaging: Place the connected heterojunction battery in the packaging mold and inject the packaging material (such as EVA film or glass glue).

[0052] The encapsulation mold is heated and pressurized to completely solidify the encapsulation material and form a tight encapsulation layer.

[0053] The encapsulation layer should have good light transmittance, waterproofness and weather resistance to protect the battery cells from erosion by the external environment.

[0054] Finished product inspection: Carry out visual inspection on the packaged heterojunction battery components to ensure that there are no defects such as cracks, bubbles and impurities.

[0055] Conduct electrical performance tests, including open circuit voltage, short circuit current, fill factor, and photoelectric conversion efficiency, to ensure that the performance of the components meets the design requirements.

[0056] Packaging and transportation: Qualified heterojunction battery components are packaged using shock-proof, moisture-proof and waterproof packaging materials to ensure the safety of the components during transportation and storage.

[0057] Mark the component model, specifications, production date, manufacturer and other information on the packaging to facilitate user identification and traceability.

[0058] Through the detailed expansion of the above embodiments, we can clearly understand the specific steps and precautions of the heterojunction battery interconnection welding method, which provides a feasible guidance scheme for actual production.

[0059] The heterojunction battery interconnection welding method of this embodiment realizes efficient and stable battery cell welding and component packaging: The steps of cleaning the cells and applying the antioxidant effectively remove contaminants from the cell surface and prevent oxidation, thereby improving the purity and adhesion of the welding interface and reducing welding defects.

[0060] The use of conductive glue to coat the welding bracket enhances the electrical conductivity and mechanical connection between the battery cell and the bracket, ensuring the firmness and stability of the welding.

[0061] The triangular frame structure of the welding bracket provides good stability and support, reducing the risk of cell breakage caused by external impact or bracket deformation during welding.

[0062] The use of shingling technology reduces the number of welding points, disperses welding stress and reduces the risk of splinters.

[0063] Strictly control the welding heating temperature and time to avoid thermal damage and stress concentration on the battery cells caused by high temperature.

[0064] The precise welding and curing process ensures good connection between the cells, reduces resistance and energy loss, and improves the electrical performance and photoelectric conversion efficiency of the components.

[0065] High-quality packaging materials and protective layers effectively isolate the battery cells from the external environment and extend the service life of the components.

[0066] Automated and sophisticated welding, curing and packaging equipment improves production efficiency and product consistency.

[0067] Through precise material selection and process control, scrap and rework rates are reduced, reducing production costs.

[0068] Strict appearance inspection and electrical performance testing ensure that the quality and performance of the components meet the design requirements.

[0069] Shock-proof, moisture-proof and waterproof packaging materials protect the components during transportation and storage.

[0070] In summary, the heterojunction cell interconnection welding method of this embodiment not only improves welding quality and component performance, but also reduces the risk of cracking and production costs, and enhances the reliability and safety of components. These effects together provide strong technical support and guarantee for the sustainable development of the solar cell industry.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A heterojunction battery interconnection welding method, characterized in that: include: Clean the battery cells; Apply conductive glue on the welding bracket; Welding several cleaned battery cells and laying them on a welding bracket, heating and curing the welding to form a battery string; Adjacent battery strings are connected by welding brackets through welding ribbons to form heterojunction batteries.

2. A heterojunction battery interconnection welding method according to claim 1, characterized in that: When cleaning the battery cell, use a cleaning solution to clean the surface of the battery cell and then spray an antioxidant.

3. A heterojunction battery interconnection welding method according to claim 1, characterized in that: The welding bracket has a triangular frame structure.

4. A heterojunction battery interconnection welding method according to claim 3, characterized in that: The welding bracket comprises two hinged edges and a movable edge, one end of the two hinged edges is hinged, and the movable edge is connected to the other end of the two hinged edges by clamping.

5. A heterojunction battery interconnection welding method according to claim 3, characterized in that: The height of the welding bracket matches the height of the battery string, and the moving side width of the welding bracket matches the width of the battery string.

6. A heterojunction battery interconnection welding method according to claim 1, characterized in that: The conductive adhesive completely covers the entire welding bracket.

7. A heterojunction battery interconnection welding method according to claim 6, characterized in that: Several adjacent battery strings are welded to a welding bracket via welding ribbons and packaged into a heterojunction battery assembly.

8. A heterojunction battery interconnection welding method according to claim 1, characterized in that: The cleaned battery cells are welded using shingling technology.

9. A heterojunction battery interconnection welding method according to claim 1, characterized in that: The welding heating temperature is less than 200℃.

10. A battery assembly, characterized in that: The heterojunction battery is manufactured by the heterojunction battery interconnection welding method as described in any one of claims 1 to 9.

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