Cooling system for welding lamp box and welding device

Abstract

The utility model relates to the technical field of photovoltaic cell production equipment, in particular to a heat dissipation system for a welding lamp box and a welding device, the welding lamp box comprises a box body and a lamp tube, the lamp tube is installed in the box body, and the heat dissipation system comprises a temperature detector, a heat dissipation fan and a control module; the temperature detector is used for detecting the temperature of the battery piece irradiated by the lamp tube; the heat dissipation fan is arranged in the box body and is used for extracting hot air in the box body; the control module is electrically connected with the temperature detector and the cooling fan, and the control module is used for adjusting the frequency of the cooling fan according to the temperature, detected by the temperature detector, of the battery piece. According to the heat dissipation system, the temperature in the welding lamp box can be monitored, regulated and controlled in real time, the temperature fluctuation range of the welding lamp box is stabilized at + / -2 DEG C, the welding temperature of the battery piece is accurately controlled, and the phenomenon of insufficient welding / over-welding of the battery piece is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic cell production equipment, in particular to a heat dissipation system and a welding device for a welding light box. Background Art

[0002] The string welding machine is the core equipment of photovoltaic modules and plays a key role in the welding process of photovoltaic module preparation. The string welding machine refers to an automated equipment that uses a mechanical transmission mechanism to transport the cells, weld the cells on a heated bottom plate, and connect the cells into a battery string. It is mainly composed of an automatic feeding system, a welding ribbon processing system, a welding system, a cell preheating system, and a flipping and collecting system.

[0003] Among them, the welding system often uses a welding light box to achieve contactless welding. During the welding process, when the battery cell is transferred to the welding area, the welding light box will radiate infrared rays of a certain wavelength in the direction of the battery cell perpendicular to the welding strip, quickly increase the temperature of the welding strip and the silver grid line of the battery cell, and complete the welding of the front and back sides of the battery cell. In the existing welding system, during the above welding process, the welding light box has the problem of excessive heat accumulation, which makes the temperature inside the welding light box unstable, resulting in large fluctuations in welding temperature, resulting in serious poor solder joints / over-soldering of the battery cell, and a high defective rate of battery cell string return. Utility Model Content

[0004] The present application provides a heat dissipation system for a welding light box, which is beneficial to reducing the welding temperature fluctuation during the welding process of the battery cells, thereby reducing the series return defect rate of the battery cells.

[0005] In a first aspect, an embodiment of the present application provides a heat dissipation system for a welding light box, wherein the welding light box comprises a box body and a lamp tube, wherein the lamp tube is installed in the box body, and the heat dissipation system comprises:

[0006] A temperature detector, used to detect the temperature of the battery cell illuminated by the lamp tube;

[0007] A heat dissipation fan is arranged in the box body and is used to extract the hot air in the box body;

[0008] A control module is electrically connected to the temperature detector and the heat dissipation fan, and the control module is used to adjust the frequency of the heat dissipation fan according to the temperature of the battery cell detected by the temperature detector.

[0009] In some embodiments, the temperature detector includes a plurality of thermocouples, and the plurality of thermocouples are evenly distributed above the battery cell to perform temperature detection on a plurality of locations of the battery cell.

[0010] In some embodiments, there are multiple welding stations for the battery cell, and the number of the temperature detectors is multiple groups, and the multiple groups of temperature detectors are arranged at intervals along the conveying direction of the battery cell, and the temperature detectors are set in a one-to-one correspondence with the welding stations.

[0011] In some embodiments, a ventilation duct is provided in the box body, the ventilation duct connects the inside and outside of the box body, the heat dissipation fan is provided in the ventilation duct, the number of the heat dissipation fans and the ventilation ducts are both multiple, and the heat dissipation fans and the ventilation ducts are provided in a one-to-one correspondence.

[0012] In a second aspect, the present application further provides a welding device, which includes the heat dissipation system as described in the first aspect above, and further includes:

[0013] Welding light boxes;

[0014] The processing platform includes a preheating base plate and a welding base plate. The preheating base plate is used to preheat the battery cell before welding. The unloading end of the preheating base plate is connected to the loading end of the welding base plate. The welding base plate is correspondingly arranged with the welding light box. The light emitting side of the welding light box faces the welding base plate. The battery cell is welded on the welding base plate.

[0015] In some embodiments, the extension length of the preheating bottom plate from its loading end to its unloading end is 70 cm to 80 cm.

[0016] In some embodiments, the processing platform also includes a first cooling base plate, the loading end of the first cooling base plate is connected to the unloading end of the welding base plate, and a heat pipe is provided in the first cooling base plate. The coolant circulates in the heat pipe to continuously cool the battery cells on the first cooling base plate.

[0017] In some embodiments, the heat conducting pipe is bent sequentially from a feeding end of the first cooling bottom plate toward a feeding end of the first cooling bottom plate to form a snake shape.

[0018] In some embodiments, the processing platform further includes a second cooling base plate, a loading end of the second cooling base plate is docked with a unloading end of the first cooling base plate, and the second cooling base plate is used to naturally cool the battery cell after being cooled by the first cooling base plate.

[0019] In some embodiments, the welding device also includes a machine table, a containing cavity is provided in the machine table, the processing platform and the welding light box are arranged in the containing cavity, and a vacuum mechanism is also provided in the containing cavity, and the vacuum mechanism is used to extract the gas in the containing cavity to accelerate the circulation of air inside and outside the containing cavity.

[0020] Compared with the prior art, this technical solution has at least the following technical effects:

[0021] In the heat dissipation system of the present application, the temperature detector can monitor the temperature of the surface of the battery cell in real time. When the temperature of the surface of the battery cell is monitored to be too high, it means that the welding temperature is too high, and the heat accumulation in the welding light box exceeds the standard. In this case, the control module will control the frequency of the heat dissipation fan to increase, increase the convection between the external cold air and the hot air in the welding light box, so that the temperature in the welding light box drops to the preset welding temperature range, that is, the welding temperature of the battery cell is reduced; correspondingly, when the temperature of the surface of the battery cell is monitored to be too low, in order to avoid affecting the welding effect, the control module will control the frequency of the heat dissipation fan to decrease, so that the temperature in the welding light box rises back to the preset welding temperature range, that is, the actual welding temperature of the battery cell rises to the preset welding temperature range. The present application sets a heat dissipation system to monitor and regulate the temperature in the welding light box in real time, so that the temperature fluctuation range of the welding light box is stabilized at ±2°C, accurately controls the welding temperature of the battery cell, reduces the occurrence of false welding / over welding of the battery cell, and can reduce the defective rate of the battery cell to 0.46%. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0023] Figure 1 This is a schematic structural diagram of a welding device of the present application in one embodiment;

[0024] Figure 2 This is a schematic diagram of the structure of the heat dissipation system of this application;

[0025] Figure 3 for Figure 1 A schematic diagram of the structure of the first cooling base plate;

[0026] Figure 4 A comparison diagram of single welding temperature rise curves of a conventional welding device and a welding device according to an embodiment of the present application;

[0027] Figure 5 A comparison diagram of temperature rise curves of series welding between a conventional welding device and a welding device according to an embodiment of the present application;

[0028] Figure 6 It is a comparison chart of the battery cell series return rate of a conventional welding device and a welding device of an embodiment of the present application.

[0029] Reference numerals:

[0030]

[0031] DETAILED DESCRIPTION

[0032] In order to better understand the technical solution of the present utility model, the embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0033] It should be clear that the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0035] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. 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 this article generally indicates that the associated objects before and after are in an "or" relationship.

[0036] The present application proposes a welding device 100 , which is suitable for welding battery cells of all sizes, and can be suitable for welding N-type batteries and P-type batteries.

[0037] Figure 1 1 is a schematic diagram of the structure of the welding device 100 of the present application in one embodiment. For the convenience of description, the transmission direction of the welding device 100 is defined as the X-axis direction, the width direction of the welding device 100 is defined as the Y-axis direction, and the height direction of the welding device 100 is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other.

[0038] The directional terms such as “upper”, “lower”, “top”, “bottom”, “left”, “right”, “front” and “rear” used in describing the welding device 100 in this embodiment are mainly based on the position of the welding device 100 in the attached drawings. Figure 1 The display orientation is explained in the figure, with the positive direction of the Z axis being the "top" and "upper", the negative direction of the Z axis being the "bottom" and "lower", the positive direction of the X axis being the "right", the negative direction of the X axis being the "left", the positive direction of the Y axis being the "back", and the negative direction of the Y axis being the "front", which does not constitute a limitation on the orientation of the welding device 100 in actual application scenarios.

[0039] See also Figure 1In this embodiment, the welding device 100 includes a processing platform and a welding light box 130. The processing platform includes a preheating base plate 121 and a welding base plate 122. The preheating base plate 121 is used to preheat the battery cell before welding. The unloading end (right end) of the preheating base plate 121 is butted with the loading end (left end) of the welding base plate 122. The welding base plate 122 is arranged corresponding to the welding light box 130. The light emitting side of the welding light box 130 faces the welding base plate 122. The battery cell is welded on the welding base plate 122. By arranging the preheating base plate 121 in front of the welding base plate 122 to preheat the battery cell, the risk of hidden cracks in the battery cell due to uneven heating during the welding process can be reduced. In more detail, the welding light box 130 includes a box body and a lamp tube. A light outlet is provided at the bottom of the box body. The lamp tube is installed in the box body and heats the battery cell on the welding base plate 122 through the light outlet. The lamp tube is an infrared lamp tube. The infrared lamp tube radiates infrared rays of a certain wavelength in the direction of the battery cell perpendicular to the welding strip, rapidly increasing the temperature of the welding strip and the silver grid line of the battery cell, and completing the welding of the battery cell.

[0040] In this embodiment, the welding device 100 also includes a machine table 110 and a conveying mechanism (not shown in the figure), the machine table 110 is provided with a accommodating cavity, the processing platform and the welding light box 130 are arranged in the accommodating cavity, and the accommodating cavity is provided with an openable and closable feeding port and a discharging port; the conveying mechanism is arranged on the machine table 110, and is used to transfer the battery cell to be processed from the preheating base plate 121 to the welding base plate 122 along the positive direction of the X-axis.

[0041] In this embodiment, the extension length of the preheating base plate 121 in the X-axis direction is 70 cm to 80 cm, and can be specifically 70 cm, 72 cm, 74 cm, 76 cm, 78 cm, 80 cm or any value therebetween. If the extension length of the preheating base plate 121 in the X-axis direction is too short, the temperature of the battery cell after preheating will still be too low, which will cause the local heating rate of the battery cell to be too fast during welding, the battery cell will be severely unevenly heated, and the battery cell will be prone to hidden cracks. If the extension length of the preheating base plate 121 in the X-axis direction is too long, the length of the machine 110 will be increased, so that the floor area of ​​the machine 110 will increase, which is not conducive to improving the space utilization of the welding device 100 and will increase the welding cost of the battery cell.

[0042] In order to achieve uniform preheating of the battery cell, the area of ​​the preheating base plate 121 is not less than the width of the battery cell. Preferably, the extension length of the preheating base plate 121 in the Y-axis direction is greater than or equal to the length of the battery cell, and the extension length in the X-axis direction is greater than or equal to the length of the battery cell. In a specific embodiment, in order to facilitate serial welding of multiple battery cells, the extension length of the preheating base plate 121 in the X-axis direction is slightly greater than the total extension length of n battery cells / half-cells in the X-axis direction, n≥2, and n is a positive integer.

[0043] During the processing of the battery cells, the transmission mechanism continuously transmits the battery cells on the processing table. The battery cells are first transmitted from the feed port to the preheating base plate 121 for preheating to a first preset temperature, which is 65°C to 85°C. Of course, those skilled in the art may also adjust the range of the first preset temperature according to actual conditions; and then transmitted to the welding base plate 122 for welding, and the welding temperature is a second preset temperature. The battery cells are successively single-welded and serially welded on the welding base plate 122, and the single-cell welding time of the battery cell is less than 0.6s. The second preset temperature includes a single-welding temperature and a serial welding temperature, which is 90°C to 110°C, and the serial welding temperature is higher than 400°C. Of course, those skilled in the art may also adjust the range of the single-welding temperature and the serial welding temperature according to actual conditions.

[0044] In order to further improve the uniformity of heating of the battery cell, the welding base plate 122 and the welding light box 130 heat the battery cell at the same time during the welding process. This arrangement can also increase the heating rate of the battery cell and shorten the welding time of the battery cell. The welding base plate 122 is heated by electric heating wire, that is, the welding base plate 122 is provided with an electric heating wire, and the welding base plate 122 is made of a heat-conducting material, such as a heat-conducting metal.

[0045] The size of the welding base plate 122 can be adjusted according to actual conditions. In an exemplary embodiment, the extension length of the welding base plate 122 along the X-axis direction is 20 cm to 40 cm, specifically 20 cm, 23 cm, 25 cm, 27 cm, 29 cm, 31 cm, 33 cm, 35 cm, 37 cm, 40 cm or any value therebetween. The extension length of the welding base plate 122 along the Y-axis direction is consistent with the extension length of the preheating plate along the Y-axis direction, and the extension length of the welding base plate 122 along the Z-axis direction is consistent with the extension length of the preheating base plate 121 along the Z-axis direction.

[0046] Please continue reading Figure 1In this embodiment, the processing platform also includes a first cooling base plate 123, the loading end (left end) of the first cooling base plate 123 is connected to the unloading end (right end) of the welding base plate 122, and a heat pipe 1231 is arranged in the first cooling base plate 123. The coolant circulates in the heat pipe 1231 to continuously cool the battery cells on the first cooling base plate 123. The first cooling base plate 123 cools the welded battery cells to a third preset temperature, and the third preset temperature is 50°C to 70°C. Of course, those skilled in the art can also adjust the range of the third preset temperature according to actual conditions.

[0047] The size of the first cooling bottom plate 123 can be adjusted according to actual conditions. In an exemplary embodiment, the extension length of the first cooling bottom plate 123 along the X-axis direction is 20 cm to 40 cm, specifically 20 cm, 23 cm, 25 cm, 27 cm, 29 cm, 31 cm, 33 cm, 35 cm, 37 cm, 40 cm or any value therebetween. The extension length of the first cooling bottom plate 123 along the Y-axis direction is consistent with the extension length of the preheating bottom plate 121 along the Y-axis direction, and the extension length of the first cooling bottom plate 123 along the Z-axis direction is consistent with the extension length of the preheating bottom plate 121 along the Z-axis direction. The material of the first cooling bottom plate 123 and the heat pipe 1231 can be selected from any one of metal, glass, ceramic and other heat-conducting materials. There are many choices for the coolant, such as water. Of course, those skilled in the art can also choose other types of coolants, which are not particularly limited in this application.

[0048] See also Figure 3 In this embodiment, the heat pipe 1231 is bent in sequence from the loading end (left end) of the first cooling base plate 123 to the unloading end (right end) of the first cooling base plate 123 to form a snake shape. This arrangement increases the length of the heat pipe 1231, that is, increases the heat exchange area between the coolant and the heat pipe 1231, thereby improving the cooling efficiency of the first cooling base plate 123.

[0049] Please continue reading Figure 1 In this embodiment, the processing platform also includes a second cooling base plate 124, the loading end (left end) of the second cooling base plate 124 is connected to the unloading end (right end) of the first cooling base plate 123, and the second cooling base plate 124 is used to naturally cool the battery cells after being cooled by the first cooling base plate 123.

[0050] The upper surface of the second cooling base plate 124 is flush with the upper surfaces of the first cooling base plate 123, the welding base plate 122 and the preheating base plate 121; the extension length of the second cooling base plate 124 along the X-axis direction and the Y-axis direction can be adjusted according to actual conditions; the material of the second cooling base plate 124 can be selected from any one of heat-conducting materials such as metal, glass, and ceramics.

[0051] In the prior art, the welding light box 130 often has excessive heat accumulation, which causes large fluctuations in the welding temperature of the battery cell (±20°C), resulting in serious poor solder joints / over-soldering of the battery cell, and a battery cell series return defect rate of up to 5.36%.

[0052] In order to solve the above technical problems, in this embodiment, the welding device 100 is further provided with a heat dissipation system 140 .

[0053] See also Figure 1 and Figure 2 In this embodiment, the heat dissipation system 140 includes a temperature detector 141, a heat dissipation fan 142 and a control module 143. The temperature detector 141 is used to detect the temperature of the battery cell irradiated by the lamp tube; the heat dissipation fan 142 is a variable frequency fan, which is arranged in the box body of the welding lamp box 130 to extract the hot air in the box body; the control module 143 is electrically connected to the temperature detector 141 and the heat dissipation fan 142, and the control module 143 is used to adjust the frequency of the heat dissipation fan 142 according to the temperature of the battery cell detected by the temperature detector 141.

[0054] In the heat dissipation system 140 of the present application, the temperature detector 141 can monitor the temperature of the battery cell surface in real time. When it is detected that the temperature of the battery cell surface is too high, it means that the welding temperature is too high and the heat accumulation in the welding light box 130 exceeds the standard. In this case, the control module 143 will control the frequency of the heat dissipation fan 142 to increase, increase the convection of external cold air and hot air in the welding light box 130, so that the temperature in the welding light box 130 drops to the preset welding temperature range, that is, the welding temperature of the battery cell is reduced; correspondingly, when it is detected that the temperature of the battery cell surface is too low, in order to avoid affecting the welding effect, the control module 143 will control the frequency of the heat dissipation fan 142 to decrease, so that the temperature in the welding light box 130 returns to the preset welding temperature range, that is, the actual welding temperature of the battery cell rises to the preset welding temperature range. As shown in Figure 4, Figure 5 and Figure 6As shown, compared with the prior art, the present application sets a heat dissipation system 140 to monitor and regulate the temperature in the welding light box 130 in real time, so that the temperature fluctuation range of the welding light box 130 is stabilized at ±2°C, and the welding temperature of the battery cell is accurately controlled to reduce the occurrence of cold soldering / over soldering of the battery cell, and the defective rate of the battery cell series return can be reduced to 0.46%.

[0055] In this embodiment, the temperature detector 141 includes a plurality of thermocouples, which are evenly distributed above the battery cell to detect the temperature of multiple locations of the battery cell. The control module 143 is used to adjust the frequency of the cooling fan 142 according to the average temperature of each location of the battery cell detected by the plurality of thermocouples. During the welding process, the height of the thermocouple from the battery cell is 3 mm to 10 mm. By setting a plurality of thermocouples to accurately monitor the real-time welding temperature of the battery cell in the welding light box 130 in all directions, the monitoring accuracy of the real-time welding temperature of the battery cell in the welding light box 130 can be improved.

[0056] It can be understood that there are multiple welding stations for battery cells on the welding base plate 122, and the number of the temperature detectors 141 is multiple groups. The multiple groups of temperature detectors 141 are arranged at intervals along the conveying direction of the battery cells (X-axis direction), and the temperature detectors 141 are set one by one corresponding to the welding stations.

[0057] In this embodiment, a ventilation duct is provided in the box body of the welding light box 130, and the ventilation duct connects the inside and the outside of the box body. The heat dissipation fan 142 is arranged in the ventilation duct. The number of the heat dissipation fan 142 and the ventilation duct is multiple, and the heat dissipation fan 142 and the ventilation duct are arranged one by one.

[0058] Furthermore, the welding device 100 also includes an exhaust mechanism 150, which is arranged in the accommodating cavity. The exhaust mechanism 150 is used to extract the gas in the accommodating cavity to accelerate the circulation of air inside and outside the accommodating cavity, and can simultaneously reduce the heat accumulation of the welding base plate 122 and the welding light box 130, which is beneficial to reduce the fluctuation of the welding temperature of the battery cell and reduce the risk of over-welding of the battery cell.

[0059] In the above embodiment, the vacuum mechanism 150 includes a vacuum pump, and the rotation speed of the vacuum pump is ≤1500RPM. By controlling the rotation speed of the vacuum pump within the above range, it is possible to avoid excessive heat loss in the accommodating cavity, which may cause the actual welding temperature to be difficult to meet the welding temperature requirements.

[0060] The present application also proposes a heat dissipation system 140 for a welding light box 130. The specific structure of the heat dissipation system 140 refers to the above-mentioned embodiment. Since the heat dissipation system 140 adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0061] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A heat dissipation system for a welding light box, the welding light box comprising a box body and a lamp tube, the lamp tube being installed in the box body, characterized in that: The heat dissipation system comprises: A temperature detector, used to detect the temperature of the battery cell irradiated by the lamp tube, wherein the temperature detector includes a plurality of thermocouples, and the plurality of thermocouples are evenly distributed above the battery cell to respectively detect the temperature of a plurality of locations of the battery cell; A heat dissipation fan is arranged in the box body and is used to extract the hot air in the box body; A control module is electrically connected to the temperature detector and the heat dissipation fan, and the control module is used to adjust the frequency of the heat dissipation fan according to the temperature of the battery cell detected by the temperature detector.

2. The heat dissipation system according to claim 1, characterized in that: There are multiple welding stations for the battery cell, and there are multiple groups of temperature detectors. The multiple groups of temperature detectors are arranged at intervals along the conveying direction of the battery cell, and the temperature detectors are arranged in a one-to-one correspondence with the welding stations.

3. The heat dissipation system according to claim 1, characterized in that: A ventilation pipe is provided in the box body, and the ventilation pipe connects the inside and outside of the box body. The heat dissipation fan is arranged in the ventilation pipe. The number of the heat dissipation fans and the ventilation pipes is multiple, and the heat dissipation fans and the ventilation pipes are arranged in a one-to-one correspondence.

4. A welding device, characterized in that: The heat dissipation system according to any one of claims 1 to 3 further comprises: Welding light boxes; The processing platform includes a preheating base plate and a welding base plate. The preheating base plate is used to preheat the battery cell before welding. The unloading end of the preheating base plate is connected to the loading end of the welding base plate. The welding base plate is correspondingly arranged with the welding light box. The light emitting side of the welding light box faces the welding base plate. The battery cell is welded on the welding base plate.

5. The welding device according to claim 4, characterized in that The extension length of the preheating bottom plate from its feeding end to its unloading end is 70 cm to 80 cm.

6. The welding device according to claim 4, characterized in that: The processing platform also includes a first cooling base plate, the loading end of the first cooling base plate is connected to the unloading end of the welding base plate, and a heat pipe is arranged in the first cooling base plate. The coolant circulates in the heat pipe to continuously cool the battery cells on the first cooling base plate.

7. The welding device according to claim 6, characterized in that The heat conducting pipe is bent in sequence from the feeding end of the first cooling bottom plate toward the feeding end of the first cooling bottom plate to form a snake shape.

8. The welding device according to claim 6, characterized in that: The processing platform also includes a second cooling bottom plate, a loading end of the second cooling bottom plate is butted against a unloading end of the first cooling bottom plate, and the second cooling bottom plate is used to naturally cool the battery cells after being cooled by the first cooling bottom plate.

9. The welding device according to claim 4, characterized in that: The welding device also includes a machine table, a containing cavity is arranged in the machine table, the processing platform and the welding light box are arranged in the containing cavity, and an exhaust mechanism is also arranged in the containing cavity, and the exhaust mechanism is used to extract the gas in the containing cavity to accelerate the circulation of air inside and outside the containing cavity.

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