Hot pressing device

Abstract

The utility model relates to a hot pressing device. The hot pressing device comprises a base, a heat source and a hot pressing piece; the heat source is connected with the hot-pressing piece so as to be used for heating the hot-pressing piece; the hot-pressing piece is provided with a hot-pressing face, the hot-pressing face is provided with an inwards-concave limiting groove, and the limiting groove is used for limiting the position of the welding strip. According to the hot-pressing device, the welding strip can be heated under the action of the heat source and the hot-pressing piece, and then welding between the welding strip and the bonding pad is completed. Meanwhile, the hot pressing face of the hot pressing piece is provided with the limiting groove so that the position of the welding strip can be limited, the risk that the welding strip deviates in the welding process can be reduced, and then the welding quality is improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular, to a hot pressing device. Background Art

[0002] In the production process of photovoltaic modules, the interconnection between cells is achieved by welding the solder tape to the pads (PADs) on the cells. In the traditional welding process, the solder tape and the cells are heated simultaneously in a whole plate by infrared radiation heating. Under the heating condition, the solder tape is welded to the pad. In the cooling stage after welding, due to the different coefficients of thermal expansion of the solder tape and the cells, the thermal expansion and contraction deformations of the solder tape and the cells do not match, which may lead to warping of the cells and affect the yield and reliability of the photovoltaic modules. In order to reduce the risk of cell warping caused by whole-plate heating, spot welding with a hot pressing head is a better method, that is, at each pad, the solder tape and the pad at this position are welded together by the hot pressing action of the hot pressing head. This method can better solve the problem of whole-plate heating of the cells, but the solder tape is prone to shift during the contact process between the hot pressing head and the solder tape, which may affect the welding quality. Utility Model Content

[0003] Based on this, it is necessary to provide a hot pressing device. The hot pressing device can reduce the risk of solder tape shift during the welding process, thereby improving the welding quality.

[0004] A hot pressing device includes a base, a heat source, and a hot pressing member; the heat source is connected to the hot pressing member to heat the hot pressing member; the hot pressing member has a hot pressing surface, and the hot pressing surface has an inwardly concave limiting groove for defining the position of the solder tape.

[0005] In some embodiments, the cross-section of the inner wall of the limiting groove is arc-shaped.

[0006] In some embodiments, the limiting groove penetrates through the opposite two side walls of the hot pressing member along a first direction to make the limiting groove a through groove.

[0007] In some embodiments, there are multiple limiting grooves, and the multiple limiting grooves are spaced along a second direction on the hot pressing member.

[0008] In some embodiments, the distance between adjacent limiting grooves is equal.

[0009] In some embodiments, the first direction and the second direction are perpendicular.

[0010] In some embodiments, there are multiple hot pressing members; the multiple hot pressing members are spaced on the base.

[0011] In some embodiments, multiple ones of the hot pressing members are arranged in parallel.

[0012] In some embodiments, the spacing between adjacent ones of the hot pressing members is equal.

[0013] In some embodiments, the hot pressing device further includes a temperature sensor and a controller; the temperature sensor and the heat source are electrically connected to the controller respectively; the temperature sensor is located on the hot pressing member to detect the temperature information of the hot pressing surface, and the controller is configured to receive the temperature information and control the heating temperature of the heat source according to the temperature information.

[0014] In the above hot pressing device, through the action of the heat source and the hot pressing member, the welding tape can be heated, and then the welding between the welding tape and the welding pad can be completed. Meanwhile, by providing the limiting groove on the hot pressing surface of the hot pressing member, the position of the welding tape can be limited, reducing the risk of the welding tape shifting during the welding process, and thus improving the welding quality. Further, during the welding process, the limiting groove can increase the contact area between the hot pressing member and the welding tape, making the force on the welding tape more uniform and further improving the welding quality. Description of the Drawings

[0015] Figure 1 It is a schematic structural diagram of a hot pressing device in an embodiment of the present application.

[0016] Figure 2 It is Figure 1 A schematic structural diagram of the corresponding hot pressing device from another perspective.

[0017] Figure 3 It is Figure 1 A schematic diagram of the corresponding hot pressing device cooperating with the welding tape during welding.

[0018] Figure 4 It is Figure 1 A schematic diagram of the corresponding hot pressing device cooperating with the welding tape from another perspective.

[0019] Explanation of the marks in the figure:

[0020] 10. Hot pressing device; 101. Base; 102. Hot pressing member; 1021. Limiting groove; 103. Temperature sensor; 20. Battery cell; 30. Welding pad; 40. Welding tape; 50. Insulating glue; 60. Workbench. Detailed Embodiments

[0021] To make the above objects, features, and advantages of the present application more apparent and understandable, the following provides a detailed description of the specific embodiments of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0022] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present application.

[0023] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0024] In the present application, unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used in the description of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] Please refer to Figure 1 and Figure 2, an embodiment of the present application provides a hot pressing device 10. The hot pressing device 10 includes a base 101, a heat source (not shown in the figure), and a hot pressing member 102. The heat source is connected to the hot pressing member 102 for heating the hot pressing member 102. The hot pressing member 102 has a hot pressing surface, and the hot pressing surface has a concave limiting groove 1021 for defining the position of the solder strip 40. In the hot pressing device 10 of this embodiment, through the action of the heat source and the hot pressing member 102, the solder strip 40 can be heated, and then the welding between the solder strip 40 and the solder pad 30 can be completed. At the same time, setting the limiting groove 1021 on the hot pressing surface of the hot pressing member 102 can limit the position of the solder strip 40, reduce the risk of the solder strip 40 shifting during the welding process, and thus improve the welding quality. Further, during the welding process, the limiting groove 1021 can increase the contact area between the hot pressing member 102 and the solder strip 40, make the force on the solder strip 40 more uniform, and further improve the welding quality.

[0027] In some embodiments, the cross-section of the inner wall of the limiting groove 1021 is arc-shaped. The cross-section of the solder strip 40 is usually oval or circular. For example, the cross-section of a conventional flat solder strip is oval, and the cross-section of a conventional round solder strip is circular. In these embodiments, when the cross-section of the inner wall of the limiting groove 1021 is arc-shaped, the shape of the inner wall of the limiting groove 1021 can better match the cross-section of the solder strip 40, which is beneficial to more stably defining the position of the solder strip 40 through the limiting groove 1021 and further reducing the risk of the solder strip 40 shifting during the welding process.

[0028] In some embodiments, the limiting groove 1021 penetrates through the opposite two side walls of the hot pressing member 102 along a first direction to make the limiting groove 1021 a through groove. At this time, the solder strip 40 can pass through the limiting groove 1021, which is beneficial to further defining the position of the solder strip 40 through the limiting groove 1021 to reduce the risk of the solder strip 40 shifting. In addition, when the limiting groove 1021 penetrates through the opposite two side walls of the hot pressing member 102 along the first direction, the corresponding position of the limiting groove 1021 on the solder strip 40 can be conveniently adjusted. During the welding process, the position of the hot pressing member 102 can be adjusted so that the limiting groove 1021 is located at the position on the solder strip 40 that needs to be welded, and then the solder strip 40 can be accurately welded. As an example of the first direction, in Figure 2 , the X direction represents the first direction. At this time, the limiting groove 1021 penetrates through the opposite two side walls of the hot pressing member 102 along the X direction for the solder strip 40 to pass through the limiting groove 1021.

[0029] In some embodiments, there are multiple limiting grooves 1021, and the multiple limiting grooves 1021 are distributed at intervals along the second direction on the hot pressing member 102. During the production process of a photovoltaic module, multiple welding tapes 40 are usually arranged on the battery cell 20 to achieve the interconnection between the battery cells 20. When there are multiple limiting grooves 1021, the multiple limiting grooves 1021 can respectively weld different welding tapes 40. For example, the number of limiting grooves 1021 on the hot pressing member 102 can be set according to the number of welding tapes 40, so that the limiting grooves 1021 on the hot pressing member 102 correspond to the welding tapes 40 one by one. In this way, multiple limiting grooves 1021 can synchronously limit multiple welding tapes 40, and then synchronously weld the multiple welding tapes 40, which is beneficial to improving the welding efficiency on the basis of reducing the risk of the welding tapes 40 shifting. As an example of the second direction, in Figure 2 where Y represents the second direction, at this time, the multiple limiting grooves 1021 are distributed at intervals along the Y direction on the hot pressing member 102. Optionally, the first direction and the second direction are perpendicular, that is, the X direction and the Y direction are perpendicular. This can facilitate a more regular design of the limiting grooves 1021 on the hot pressing member 102, and can also make the arrangement of the limiting grooves 1021 on the hot pressing member 102 better match the arrangement of the welding tapes 40 on the battery cell 20, thereby improving the welding effect and welding efficiency.

[0030] In some embodiments, the distance between adjacent limiting grooves 1021 is equal. In Figure 2 the illustrated embodiment, there are four limiting grooves 1021 on each hot pressing member 102, and the distance between adjacent limiting grooves 1021 is equal. Optionally, there are at least three limiting grooves 1021. It can be understood that when designing the number of limiting grooves 1021, the number of limiting grooves 1021 on the hot pressing member 102 can also be designed according to the number of welding tapes 40 on the battery cell 20. Optionally, the number of limiting grooves 1021 on each hot pressing member 102 can be two, five, six, seven, eight, etc. Further optionally, the multiple limiting grooves 1021 are arranged in parallel.

[0031] Please refer to Figure 2 and Figure 4 , in some embodiments, there are multiple hot pressing members 102. The multiple hot pressing members 102 are distributed at intervals on the base 101. By arranging the multiple hot pressing members 102 at intervals, different positions on the same welding tape 40 can be welded synchronously, which is beneficial to improving the welding efficiency. It can be understood that there are multiple limiting grooves 1021 on each hot pressing member 102, so that different welding positions on different welding tapes 40 can be welded synchronously, which is beneficial to further improving the welding efficiency.

[0032] Further, when multiple hot pressing members 102 are distributed at intervals, the cell 20 can be divided into a heating area and a non-heating area, reducing the heated area of the cell 20 during the welding process, reducing the degree of deformation mismatch between the welding tape 40 and the cell 20 during the cooling stage, reducing the thermal stress on the cell 20, reducing the risk of warping of the cell 20, and thus improving the yield and reliability of the photovoltaic module. For example, during welding, the area corresponding to the hot pressing member 102 is the heating area, and the area between adjacent hot pressing members 102 is the non-heating area. This can reduce the heated expansion area of the cell 20, thereby reducing the thermal stress on the cell 20, reducing the warping degree of the cell 20 during the cooling stage after welding, and improving the welding yield. Additionally, the non-heating area can serve as a stress release area for the welding tape 40 and the cell 20 in the heating area during the cooling stage, further reducing the thermal stress on the cell 20, reducing the warping degree of the cell 20, and improving the welding yield.

[0033] In some embodiments, multiple hot pressing members 102 are arranged in parallel. Arranging multiple hot pressing members 102 in parallel can better adapt to the welding tape 40 on the cell 20 and improve the welding effect.

[0034] In some embodiments, the distance between adjacent hot pressing members 102 is equal. In Figure 2 and Figure 4 In the illustrated embodiment, there are four hot pressing members 102. Optionally, there are at least three hot pressing members 102. It can be understood that the number of hot pressing members 102 can be designed according to the actual welding requirements. For example, the hot pressing members 102 can also be two, five, six, seven, eight, etc.

[0035] Please refer to Figure 1 and Figure 3 , in some embodiments, the hot pressing device 10 further includes a temperature sensor 103 and a controller (not shown in the figure). The temperature sensor 103 and the heat source are electrically connected to the controller respectively. The temperature sensor 103 is located on the hot pressing member 102 to detect the temperature information of the hot pressing surface, and the controller is used to receive the temperature information and control the heating temperature of the heat source according to the temperature information. Through the settings of the temperature sensor 103 and the controller, the temperature of the hot pressing surface can be detected and adjusted in real time. When the temperature of the hot pressing surface is too low, the controller can control the heat source to increase the heating temperature to raise the temperature of the hot pressing surface. When the temperature of the hot pressing surface is too high, the controller can control the heat source to reduce the heating temperature to lower the temperature of the hot pressing surface. This facilitates controlling the temperature of the hot pressing surface within a suitable range, thereby improving the welding effect. Further optionally, there are multiple temperature sensors 103, and the multiple temperature sensors 103 correspond one-to-one to the limiting grooves 1021 on the hot pressing member 102. Optionally, the temperature sensor 103 is a thermocouple.

[0036] Please refer to againFigure 3 and Figure 4 During the welding process, the battery cell 20 can be placed on the workbench 60, and the hot pressing member 102 can be moved to the position where the welding tape 40 needs to be welded, so that the limiting groove 1021 on the hot pressing member 102 corresponds to the welding tape 40, and the position of the welding tape 40 can be limited through the limiting groove 1021. Then, through the heating effect of the heat source, the welding tape 40 and the pad 30 are welded together.

[0037] It can be understood that an insulating adhesive 50 is provided on the battery cell 20, and the insulating adhesive 50 can be set as a conventional insulating adhesive 50 in the photovoltaic module, which will not be elaborated here.

[0038] It can be understood that there are many pads 30 on the battery cell 20, and multiple welding tapes 40 are required, and each welding tape 40 corresponds to multiple pads 30. At this time, through multiple hot pressing members 102 arranged at intervals, and multiple limiting grooves 1021 are provided on each hot pressing member 102, the welding tapes 40 at the positions of multiple pads 30 can be welded simultaneously, improving the welding efficiency. At the same time, when the welding tapes 40 at the positions of multiple pads 30 are welded simultaneously, the risk of chip breakage due to uneven force on the pads 30 can be reduced. In addition, compared with the traditional method of spot welding each pad 30, welding the welding tapes 40 at the positions of multiple pads 30 simultaneously can significantly reduce the force frequency on the battery cell 20, and thus can reduce the risk of hidden cracks in the battery cell 20. Optionally, during the welding process, the hot pressing member 102 is perpendicularly arranged with respect to the welding tape 40.

[0039] It can be understood that in order to improve the photoelectric conversion efficiency of the photovoltaic module, when designing the photovoltaic module, both the positive electrode and the negative electrode of the battery cell 20 are arranged on the back surface of the battery cell 20, which is beneficial to increasing the light-receiving area of the battery cell 20. Such a photovoltaic module has more pads 30 and welding tapes 40 on the back surface of its battery cell 20. By using the hot pressing device 10 in the present application for welding, multiple pads 30 and welding tapes 40 can be welded synchronously, effectively improving the welding quality and welding efficiency.

[0040] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0041] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims, and the specification and the drawings can be used to explain the content of the claims.

Claims

1. A hot pressing device (10), characterized in that: The invention comprises a base (101), a heat source and a hot pressing piece (102); the heat source is connected to the hot pressing piece (102) for heating the hot pressing piece (102); the hot pressing piece (102) has a hot pressing surface, the hot pressing surface has an inwardly concave limiting groove (1021), and the limiting groove (1021) is used to limit the position of a welding strip (40).

2. The hot pressing device (10) according to claim 1, characterized in that: The cross section of the inner wall of the limiting groove (1021) is arc-shaped.

3. The hot pressing device (10) according to claim 1, characterized in that: The limiting groove (1021) penetrates through two opposite side walls of the hot pressing member (102) along a first direction so as to make the limiting groove (1021) a through groove.

4. The hot pressing device (10) according to claim 3, characterized in that: There are a plurality of the limiting grooves (1021), and the plurality of limiting grooves (1021) are distributed on the hot pressing part (102) at intervals along the second direction.

5. The hot pressing device (10) according to claim 4, characterized in that: The spacing between adjacent limiting grooves (1021) is equal.

6. The hot pressing device (10) according to claim 4, characterized in that: The first direction and the second direction are perpendicular.

7. The hot pressing device (10) according to any one of claims 1 to 6, characterized in that: There are a plurality of the hot pressing parts (102); the plurality of the hot pressing parts (102) are distributed on the base (101) at intervals.

8. The hot pressing device (10) according to claim 7, characterized in that: A plurality of the hot pressing parts (102) are arranged in parallel.

9. The hot pressing device (10) according to claim 8, characterized in that: The spacing between adjacent hot pressing parts (102) is equal.

10. The hot pressing device (10) according to any one of claims 1 to 6, characterized in that: The hot pressing device (10) further comprises a temperature sensor (103) and a controller; the temperature sensor (103) and the heat source are respectively electrically connected to the controller; the temperature sensor (103) is located on the hot pressing member (102) for detecting temperature information of the hot pressing surface, and the controller is used to receive the temperature information and control the heating temperature of the heat source according to the temperature information.

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