Laser enhanced contact optimization equipment and solar cell ohmic contact optimization method

Abstract

The present application relates to a laser enhanced contact optimization device and a solar cell ohmic contact optimization method, which includes a carrier component, a cooling component and a laser component. The carrier component is used to carry a cell and apply a reverse bias voltage to the cell; the cooling component is used to cool the cell; and the laser component is used to project a shaping light spot onto the cell. When the cell is processed by the above-mentioned device, the cell is carried by the carrier component and a reverse bias voltage is applied, and the cooling component cools the cell before the laser projects the shaping light spot, so that the temperature of the cell is lower during laser shaping. In this way, when the shaping light spot is projected onto the cell, the built-in electric field of the cell can be weakened, which is conducive to injecting more carriers into the cell, thereby reducing the contact resistance between the metal layer and the semiconductor layer of the cell, and the passivation layer will not be damaged, thereby making the photoelectric conversion efficiency of the finally prepared cell higher.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a laser enhanced contact optimization device and an ohmic contact optimization method for solar cells. Background Art

[0002] With the development demand of green environmental protection and energy saving, photovoltaic technology has emerged, which realizes the renewable utilization of energy through photoelectric conversion of renewable resources such as sunlight. However, due to the low photoelectric conversion efficiency of solar cells, the application scenarios of solar cells are limited, so it is particularly important to improve the photoelectric conversion efficiency of solar cells. Summary of the invention

[0003] Based on this, it is necessary to provide a laser enhanced contact optimization device to improve the photoelectric conversion efficiency of the battery cell.

[0004] A laser enhanced contact optimization device, comprising:

[0005] A carrier assembly, the carrier assembly is used to carry the battery cell and apply a reverse bias voltage to the battery cell;

[0006] A cooling component, the cooling component is used to cool the battery cell;

[0007] A laser component is used to project a shaped light spot onto the battery cell.

[0008] In one embodiment, the cooling assembly includes a cooling element and an air cooling pipe connected to the cooling element; the cooling element is used to provide cooling gas to the air cooling pipe, and the air cooling pipe is provided with an air outlet;

[0009] The carrying assembly comprises a carrying platform, the carrying platform has a carrying surface, and the carrying surface is used to carry the battery cell;

[0010] The air outlet is configured to face the bearing surface.

[0011] In one of the embodiments, the air cooling pipe is an annular component connected end to end, the annular component encloses an annular area, and the annular area is arranged opposite to the bearing surface.

[0012] In one embodiment, the outer diameter of the annular area is larger than the outer contour size of the bearing surface.

[0013] In one embodiment, the bearing assembly further includes a conveying member, and the bearing platform is slidably disposed on the conveying member.

[0014] In one of the embodiments, the density of the air outlet holes on the air cooling pipe gradually decreases along the conveying direction of the supporting platform.

[0015] In one embodiment, the cooling assembly further includes a liquid cooling pipe, and the liquid cooling pipe is in contact with the supporting platform.

[0016] In one of the embodiments, the laser enhanced contact optimization device further includes a controller;

[0017] A temperature sensor is provided on the carrier platform, and the temperature sensor is electrically connected to the controller;

[0018] The liquid cooling pipe is provided with a flow regulating valve, and the flow regulating valve is electrically connected to the controller.

[0019] In one of the embodiments, an air flow regulating valve is provided on the air cooling pipe, and the air flow regulating valve is electrically connected to the controller.

[0020] In one of the embodiments, the carrier assembly further includes a power source and electrodes;

[0021] The first end of the power supply is electrically connected to the supporting platform, the second end of the power supply is electrically connected to the input end of the electrode, and the output end of the electrode is used to be electrically connected to the battery cell.

[0022] In one embodiment, the electrode includes a main line and a plurality of sub-lines connected to the main line;

[0023] The main line is electrically connected to the power source, and the sub-line is used to be electrically connected to the gate line of the battery cell.

[0024] The present application also provides a method for optimizing ohmic contacts of solar cells, which uses the laser enhanced contact optimization device described in any of the above embodiments to perform laser enhanced contact optimization on a cell sheet of a solar cell, and the method for optimizing ohmic contacts of solar cells comprises:

[0025] Placing the battery cell on the carrier assembly;

[0026] Using a cooling component to cool the battery cell so that the temperature of the battery cell reaches a preset temperature;

[0027] A laser component is used to project a shaped light spot onto the battery cell, and a carrier component is used to apply a reverse bias voltage to the battery cell.

[0028] In one embodiment, the preset temperature T satisfies the condition:

[0029] 5℃≤T≤50℃.

[0030] In one embodiment, the step of using a laser component to project a shaped light spot on the cell specifically includes:

[0031] In a dark field environment, the laser assembly is used to project a shaped light spot onto the cell;

[0032] The dark field environment is an environment with a light intensity less than 10 W / m 2 .

[0033] When the battery cell is processed by the above-mentioned laser enhanced contact optimization equipment, the battery cell is supported by the supporting component and a reverse bias voltage is applied to the battery cell, and the cooling component cools the battery cell before the laser component projects a laser shaping spot on the battery cell, thereby making the temperature of the battery cell lower during laser shaping. In this way, when the laser component projects a shaping spot on the battery cell, the built-in electric field of the battery cell can be weakened, which is beneficial to inject more carriers into the battery cell, thereby reducing the contact resistance between the metal layer and the semiconductor layer of the battery cell, and the passivation layer will not be damaged, so that the performance of the finally prepared battery cell is better and the photoelectric conversion efficiency is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A first schematic diagram of a carrier assembly, a cooling assembly, and a battery cell in a laser enhanced contact optimization device provided in one embodiment of the present application.

[0035] Figure 2 for Figure 1 A second schematic diagram of the carrier assembly, battery cell and cooling assembly in the laser enhanced contact optimization device is shown.

[0036] Figure 3 for Figure 1 The schematic diagram of the connection between the carrier component, battery cell, cooling component and controller in the laser enhanced contact optimization device is shown.

[0037] Figure 4 for Figure 1 A schematic diagram of the carrier component, battery cell, cooling component and laser component in the laser enhanced contact optimization device is shown.

[0038] Figure numerals: 100-carrying component; 110-carrying platform; 111-temperature sensor; 120-electrode; 130-conveying member; 200-cooling component; 210-air cooling pipe; 211-air outlet; 220-cooling member; 230-liquid cooling pipe; 231-liquid inlet channel; 232-liquid outlet channel; 233-flow regulating valve; 300-laser component; 310-scanning galvanometer; 320-focusing lens; 330-laser optical path; 400-controller; 500-battery cell. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth 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 violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0040] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0041] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0042] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0043] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0044] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0045] The solar cell includes a crystalline silicon cell 500 and a grid line, which is made of a metal material and is arranged at intervals in the crystalline silicon cell 500. In the preparation of high-efficiency crystalline silicon solar cells, reducing the contact resistance of the ohmic contact is an important part of improving the conversion efficiency. The formation of a conventional crystalline silicon solar cell electrode 120 depends on the laying of the metal slurry and the subsequent sintering process. The formation of an effective metal-semiconductor contact requires a higher sintering temperature. On the one hand, the high sintering temperature increases the fill factor (FF) of the photovoltaic cell, but on the other hand, it leads to an increase in metal-induced recombination, which limits the improvement in the conversion efficiency of the photovoltaic cell. Therefore, reducing the metal-semiconductor contact resistance is a difficulty that needs to be overcome in the preparation of high-efficiency crystalline silicon solar cells.

[0046] The applicant discovered that the previous process before the battery cell 500 is subjected to laser projection shaping spot treatment is a high-temperature sintering process. After the battery cell 500 is sintered at high temperature through this process, the temperature of the battery cell 500 is close to 100°. At this time, when the shaping spot is projected to the battery cell 500 by the laser component 300, due to the strong built-in electric field of the battery cell 500, the concentration of carriers injected by the laser component 300 into the battery cell 500 is low, the contact resistance between the metal layer and the semiconductor layer of the battery cell 500 is high, and the passivation layer is easily damaged, resulting in poor performance of the finally prepared battery cell 500 and low photoelectric conversion efficiency. Based on the above problems, the present application provides a laser enhanced contact optimization device.

[0047] See also Figure 1 and Figure 4, Figure 1 A first schematic diagram of a carrier assembly 100, a cooling assembly 200, and a battery cell 500 in a laser enhanced contact optimization device provided in an embodiment of the present application is shown. Figure 4 Shows Figure 1 The schematic diagram of the carrier component 100, the battery cell 500, the cooling component 200 and the laser component 300 in the laser enhanced contact optimization device shown. The laser enhanced contact optimization device provided in one embodiment of the present application includes a carrier component 100, a cooling component 200 and a laser component 300. The carrier component 100 is used to carry the battery cell 500 and apply a reverse bias voltage to the battery cell 500; the cooling component 200 is used to cool the battery cell 500; and the laser component 300 is used to project a shaped light spot onto the battery cell 500.

[0048] When the battery cell 500 is processed by the above-mentioned laser enhanced contact optimization equipment, the battery cell 500 is supported by the supporting component 100 and a reverse bias voltage is applied to the battery cell 500, and the cooling component 200 cools the battery cell 500 before the laser component 300 projects a laser shaping spot on the battery cell 500, so that the temperature of the battery cell 500 is lower during laser shaping. In this way, when the laser component 300 projects a shaping spot on the battery cell 500, the built-in electric field of the battery cell 500 can be weakened, which is beneficial to inject more carriers into the battery cell 500, thereby reducing the contact resistance between the metal layer and the semiconductor layer of the battery cell 500, and the passivation layer will not be damaged, so that the finally prepared battery cell 500 has better performance and higher photoelectric conversion efficiency.

[0049] It should be noted that in the present application, the shaped light spot refers to the combination of light spots projected by the laser component 300 onto the battery cell 500, and its shape can be a plurality of local light spots arranged in a dot matrix or a dot column, or it can be a continuous single light spot, as long as it can cooperate to realize the laser enhanced contact optimization process.

[0050] It should be noted that the front side of the cell 500 receiving the shaped light spot has a Figure 4 A plurality of main grid lines extending in the xx' direction and spaced along the yy' direction, and a plurality of fine grid lines extending in the yy' direction and spaced along the xx' direction. When the laser assembly 300 projects a shaped light spot on the cell 500, a high current density flows through the contact point between the metal and the semiconductor in a local part of each fine grid line, generating a large local heat, promoting the mutual diffusion of the metal and semiconductor materials, and forming a local sub-micron point contact after the contact point is cooled, thereby achieving the improvement of the ohmic contact of the cell 500.

[0051] In one of the embodiments, when the laser enhanced contact optimization device provided by the present application performs laser enhanced contact optimization on the battery cell 500, while applying a reverse bias voltage to the battery cell 500 through the carrier component 100, the shaping light spot projected by the laser component 300 can be projected only on part of the fine grid lines on the battery cell 500, and the entire surface optimization of the battery cell 500 is completed through multiple projections. Alternatively, the shaping light spot can be projected on all the fine grid lines, and the entire surface optimization of the battery cell 500 is completed through one projection. It should be noted that, since for each fine grid line, the shaping light spot only irradiates its local area, even if multiple fine grid lines are irradiated at the same time, it is still possible to avoid the phenomenon of mutual shunting and heat transfer caused by the connection of a fine grid line to which the partitions of a larger area are simultaneously under the action of current, so in the present invention, there is no specific restriction on the number of fine grid lines projected by the shaping light spot.

[0052] The following is a detailed description of the laser enhanced contact optimization equipment. Figure 2 and Figure 3 , Figure 2 , shows Figure 1 A second schematic diagram of the carrier assembly 100, the battery cell 500 and the cooling assembly 200 in the laser enhanced contact optimization device is shown. Figure 3 Shows Figure 1 The diagram shows the connection between the carrier assembly 100, the battery cell 500, the cooling assembly 200 and the controller 400 in the laser enhanced contact optimization device.

[0053] See also Figure 2 The cooling assembly 200 of the laser enhanced contact optimization device provided in some embodiments of the present application includes a cooling member 220 and an air cooling pipe 210 connected to the cooling member 220; the cooling member 220 is used to provide cooling gas to the air cooling pipe 210, and the air cooling pipe 210 is configured with an air outlet 211; the supporting assembly 100 includes a supporting platform 110, and the supporting platform 110 has a supporting surface, and the supporting surface is used to support the battery cell 500; the air outlet 211 is configured to face the supporting surface. Before the battery cell 500 is laser-shaped, cold air is blown to the supporting surface through the air outlet 211 on the air cooling pipe, thereby achieving rapid cooling of the battery cell 500. In one embodiment, the temperature of the battery cell 500 can be reduced to below 40°C through the air cooling pipe 210.

[0054] See also Figure 1 , Figure 3 and Figure 4The air cooling pipe 210 of the laser enhanced contact optimization device provided in one embodiment of the present application is a ring-shaped component connected end to end, and the ring-shaped component encloses a ring-shaped area, and the ring-shaped area is arranged opposite to the bearing surface. By setting the air cooling pipe 210 as a ring-shaped component, and the ring-shaped area enclosed by the ring-shaped component is arranged opposite to the bearing surface, the air cooling pipe 210 can perform a ring-shaped blowing and cooling operation facing the battery cell 500 on the bearing surface, and the cooling efficiency for the battery cell 500 is high, and the time required for the entire cooling process is also less.

[0055] In some embodiments, the outer diameter of the annular region is larger than the outer contour size of the bearing surface. By setting the inner diameter of the annular region to be larger than the size of the bearing surface, the entire periphery of the battery cell 500 carried on the bearing surface can be subjected to an annular blowing cooling operation through the air cooling pipe 210, which has a high cooling efficiency for the battery cell 500 and takes less time for the entire cooling process.

[0056] It should be noted that when the bearing surface is a rectangular structure, the outer diameter of the annular area is greater than the length of the rectangular structure. When the bearing surface is a square structure, the outer diameter of the annular area is greater than the side length of the square structure. Of course, in other embodiments, the bearing surface can also be any other special-shaped structure, and there is no special limitation on this, as long as the orthographic projection of the annular area on the bearing surface can completely cover the entire bearing surface.

[0057] See also Figure 1 and Figure 2 The carrier assembly 100 of the laser enhanced contact optimization device provided in some embodiments of the present application further includes a conveyor 130, and the carrier platform 110 is slidably disposed on the conveyor 130, so as to realize the movement of the battery cell 500 in different stations, and when the laser assembly 300 projects a shaped spot to the battery cell 500, the front of the entire battery cell 500 can realize laser enhanced contact optimization. Optionally, the conveyor 130 can be a conveyor chain or a conveyor slide rail chute structure, etc., which is not particularly limited.

[0058] In some embodiments, the density of the air outlet holes 211 on the air cooling tube 210 gradually decreases along the conveying direction of the carrier 110. Specifically, the conveying direction of the carrier 110 is also the conveying direction of the battery cell 500. Figure 1The x' in the figure points to the direction of x. Since the previous process of the battery cell 500 before the laser projection shaping spot treatment is a high temperature sintering process, after the battery cell 500 is sintered at high temperature through this process, the battery cell 500 is transported by a conveyor 130. The temperature of the front end of the battery cell 500 along the transport direction is relatively low, while the temperature of the rear end is relatively high due to being close to the high temperature sintering station. At this time, the density of the air outlet holes 211 on the air cooling tube 210 is set to gradually decrease along the transport direction of the carrier 110, so that when the battery is just transported to the bottom of the air cooling tube 210, it can be quickly cooled down, thereby making the cooling efficiency of the entire battery cell 500 relatively high.

[0059] In some embodiments, the distance between the air cooling tube 210 and the supporting surface is inversely proportional to the density of the air outlet holes 211 on the air cooling tube 210. That is, the farther the distance from the supporting surface, the greater the density of the air outlet holes 211 on the air cooling tube 210, thereby effectively ensuring the heat dissipation of the battery cell 500.

[0060] See also Figure 3 , the cooling assembly 200 of the laser enhanced contact optimization device provided in one embodiment of the present application also includes a liquid cooling tube 230, and the liquid cooling tube 230 is in contact with the carrier 110. By contacting the liquid cooling tube 230 with the carrier 110, the liquid cooling tube 230 cools the carrier 110, and then cools the battery cell 500 carried on the carrier 110. That is to say, in the present application, the front of the battery cell 500 is cooled by the air cooling tube 210, and the back of the battery cell 500 is cooled by the liquid cooling tube 230, so that both the front and back of the battery cell 500 can be cooled quickly, shortening the time required for the entire battery cell 500 to cool down, so that the temperature of the battery cell 500 can be quickly reduced to room temperature or below room temperature. In one embodiment, the temperature of the battery cell 500 can continue to drop to below 25°C through the liquid cooling tube 230.

[0061] See also Figure 3 Specifically, the liquid cooling pipe 230 includes a liquid inlet channel 231 and a liquid outlet channel 232 respectively contacting the carrier 110. The liquid inlet channel 231 is used to inject the coolant, and the liquid outlet channel 232 is used to discharge the coolant. Through the circulation of the coolant, the liquid cooling pipe 230 can cool the carrier 110.

[0062] See also Figure 3, the laser enhanced contact optimization device provided in one embodiment of the present application further includes a controller 400; a temperature sensor 111 is provided on the carrier 110, and the temperature sensor 111 is electrically connected to the controller 400; a flow regulating valve 233 is provided on the liquid cooling pipe 230, and specifically, the flow regulating valve 233 is provided on the liquid inlet channel 231, and the flow regulating valve 233 is electrically connected to the controller 400. By providing the temperature sensor 111, the temperature sensor 111 can measure the temperature of the carrier 110, and then determine the temperature of the battery cell 500. By electrically connecting the temperature sensor 111 to the controller 400, and providing the flow regulating valve 233 on the liquid cooling pipe 230, and the flow regulating valve 233 is electrically connected to the controller 400, the controller 400 can adjust the flow regulating valve 233 according to the temperature value measured by the temperature sensor 111, and then adjust the water flow rate of the liquid cooling pipe 230, so that the cooling operation of the battery cell 500 is more intelligent and accurate, and the waste of energy is reduced. For example, when the temperature of the battery cell 500 has dropped below the preset temperature, the flow regulating valve 233 can be adjusted by the controller 400 to adjust the water outlet flow rate of the liquid cooling pipe 230 to a smaller value or a non-water-discharging state; and when the temperature of the battery cell 500 is much higher than the preset temperature, the flow regulating valve 233 can be adjusted by the controller 400 to adjust the water outlet flow rate of the liquid cooling pipe 230 to a larger value to speed up the cooling rate of the battery cell 500.

[0063] See also Figure 3 The air cooling pipe 210 of the laser enhanced contact optimization device provided in one embodiment of the present application is provided with an air flow regulating valve, and the air flow regulating valve is electrically connected to the controller 400. By electrically connecting the controller 400 to the air flow regulating valve, the controller 400 can adjust the air flow regulating valve according to the temperature value measured by the temperature sensor 111, and then adjust the air flow rate of the air cooling pipe 210, so that the cooling operation of the battery cell 500 is more intelligent and accurate, and the waste of energy is reduced.

[0064] It should be noted that when laser enhanced contact optimization is performed on the battery cell 500, the air cooling tube 210 and the liquid cooling tube 230 can work simultaneously with the laser assembly 300, so that the temperature of the battery cell 500 is always maintained in a relatively low temperature range during the entire laser enhanced contact optimization process.

[0065] See also Figure 4 In some embodiments, the laser assembly 300 includes a scanning galvanometer 310 and a focusing mirror 320. The laser light path 330 passes through the scanning galvanometer 310 and the focusing mirror 320 and then projects to the front of the battery cell 500, thereby achieving laser enhanced contact optimization of the battery cell 500.

[0066] See also Figure 4 , the carrier assembly 100 of the laser enhanced contact optimization device provided in one embodiment of the present application also includes a power supply (not shown in the figure) and an electrode 120; the first end of the power supply is electrically connected to the carrier 110, the second end of the power supply is electrically connected to the input end of the electrode 120, and the output end of the electrode 120 is used to be electrically connected to the battery cell 500. By electrically connecting the first end of the power supply to the carrier 110, the second end of the power supply is connected to the input end of the electrode 120, and the output end of the electrode 120 is electrically connected to the battery cell 500, a reverse bias voltage is applied to the battery cell 500. Specifically, the positive electrode of the power supply is electrically connected to the carrier 110, and the carrier 110 is made of metal; the negative electrode of the power supply is electrically connected to the electrode 120. The voltage of the power supply is stabilized at a certain value of 5V-30V. Optionally, the voltage of the power supply is 5V, 30V or 15V.

[0067] See also Figure 4 The electrode 120 of the laser enhanced contact optimization device provided in one embodiment of the present application includes a main line (not shown in the figure) and a plurality of sub-lines connected to the main line; the main line is electrically connected to the power supply, and the sub-lines are used to electrically connect to the grid lines of the battery cell 500. By connecting a plurality of sub-lines to the main line, the electrical connection between the electrode 120 and the battery cell 500 is achieved, which is relatively simple and convenient. It should be noted that the sub-line can be directly pressed on the main grid line on the front of the battery cell 500, or it can be electrically connected to the main grid line without being pressed on the main grid line. By increasing the pressing and lifting action of the sub-line relative to the main grid line, the problem of no electrode 120 blocking when laser shaping the battery cell 500 is achieved.

[0068] In some of the embodiments, the sub-line can be a probe, which is connected to the end of the main grid line by the probe and a first potential is given to the probe, thereby achieving electrical connection between the sub-line and the grid line of the battery cell 500. This method does not block the shaping spot and is conducive to precise control of the optimization effect.

[0069] In some other embodiments, the sub-wire is a conductive wire, which is abutted against the main grid line of the battery cell 500 by the conductive wire, and a first potential is given to the conductive wire, thereby achieving electrical connection between the sub-wire and the grid line of the battery cell 500.

[0070] The present application also provides a method for optimizing ohmic contacts of solar cells, which uses the laser enhanced contact optimization device described in any of the above embodiments to perform laser enhanced contact optimization on a cell 500 of a solar cell. The method for optimizing ohmic contacts of solar cells includes:

[0071] S10 : placing the battery cell 500 on the carrier assembly 100 .

[0072] The battery cell 500 is supported by the support assembly 100 , so that a bearing force can be applied to the battery cell 500 through the support assembly 100 during the ohmic contact optimization process.

[0073] S20: Cooling the battery cell 500 using the cooling assembly 200 so that the temperature of the battery cell 500 reaches a preset temperature.

[0074] The battery cell 500 is cooled by the cooling assembly 200 so that the temperature of the battery cell 500 reaches a preset temperature, thereby effectively reducing the temperature of the battery cell 500.

[0075] S30: using the laser assembly 300 to project a shaped light spot onto the battery cell 500, and using the carrier assembly 100 to apply a reverse bias voltage to the battery cell 500.

[0076] The laser assembly 300 projects a shaping spot onto the cell 500, and a pressure-bearing assembly is used to apply a reverse bias voltage to the cell 500, so that the cell 500 can be laser-enhanced contact optimized. At the same time, since the method performs laser shaping on the cell 500 after the temperature of the cell 500 is lowered, the temperature of the cell 500 during laser shaping is relatively low, so that when the laser assembly 300 projects a shaping spot onto the cell 500, the built-in electric field of the cell 500 can be weakened, which is beneficial for injecting more carriers into the cell 500, thereby reducing the contact resistance between the metal layer and the semiconductor layer of the cell 500, and the passivation layer will not be damaged, thereby making the final prepared cell 500 have better performance and higher photoelectric conversion efficiency.

[0077] In one of the embodiments, the preset temperature T satisfies the condition: 5°C≤T≤50°C. By setting the value of the preset temperature T within a range of greater than or equal to 5°C and less than or equal to 50°C, when the laser assembly 300 projects a shaped light spot on the battery cell 500, the temperature of the battery cell 500 can be within a lower range, and the laser enhanced contact optimization effect of the battery cell 500 is better. In one of the embodiments, the preset temperature T is 5°C. In another embodiment, the preset temperature T is 50°C. In another embodiment, the preset temperature T is 25°C.

[0078] In one of the embodiments, step S30: using the laser assembly 300 to project a shaped light spot onto the battery cell 500 specifically includes: in a dark field environment, using the laser assembly 300 to project a shaped light spot onto the battery cell 500; wherein the dark field environment is an environment light intensity less than 10W / m2.

[0079] By using the laser assembly 300 to project a shaped light spot onto the battery cell 500 in a dark field environment, the influence of external ambient light on laser shaping can be reduced when performing laser enhanced contact optimization on the battery cell 500, thereby achieving a better effect of laser enhanced contact optimization on the battery cell 500.

[0080] It should be understood that in the embodiments of the present application, at least part of the steps in the preparation method may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed in turn or alternately with other steps or at least part of the steps or stages in other steps.

[0081] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A laser enhanced contact optimization device, characterized in that: The laser enhanced contact optimization device comprises: A carrier assembly (100), the carrier assembly (100) comprising a carrier platform (110), the carrier platform (110) having a carrier surface, the carrier surface being used to carry a battery cell (500) and apply a reverse bias voltage to the battery cell (500); A cooling assembly (200), the cooling assembly (200) being used to cool the battery cell (500); the cooling assembly (200) comprising a cooling element (220) and an air cooling pipe (210) in communication with the cooling element (220); the cooling element (220) being used to provide cooling gas to the air cooling pipe (210); the air cooling pipe (210) being provided with air outlet holes (211); the density of the air outlet holes (211) on the air cooling pipe (210) gradually decreases along the conveying direction of the carrier platform (110); the air outlet holes (211) are configured to face the carrier surface; A laser component (300) is used to project a shaped light spot onto the battery sheet (500).

2. The laser enhanced contact optimization device according to claim 1, characterized in that: The air cooling pipe (210) is an annular component connected end to end, the annular component encloses an annular area, and the annular area is arranged opposite to the bearing surface.

3. The laser enhanced contact optimization device according to claim 2, characterized in that: The outer diameter of the annular area is greater than the outer contour size of the bearing surface.

4. The laser enhanced contact optimization device according to claim 1, characterized in that: The bearing assembly (100) further comprises a conveying member (130), and the bearing platform (110) is slidably disposed on the conveying member (130).

5. The laser enhanced contact optimization device according to claim 1, characterized in that: The cooling assembly (200) further comprises a liquid cooling pipe (230), wherein the liquid cooling pipe (230) is in contact with the supporting platform (110).

6. The laser enhanced contact optimization device according to claim 5, characterized in that: The laser enhanced contact optimization device also includes a controller (400); A temperature sensor (111) is provided on the carrier platform (110), and the temperature sensor (111) is electrically connected to the controller (400); The liquid cooling pipe (230) is provided with a flow regulating valve (233), and the flow regulating valve (233) is electrically connected to the controller (400).

7. The laser enhanced contact optimization device according to claim 6, characterized in that: The air cooling pipe (210) is provided with an air flow regulating valve, and the air flow regulating valve is electrically connected to the controller (400).

8. The laser enhanced contact optimization device according to any one of claims 1 to 7, characterized in that: The bearing assembly (100) further comprises a power source and an electrode (120); The first end of the power source is electrically connected to the carrier platform (110), the second end of the power source is electrically connected to the input end of the electrode (120), and the output end of the electrode (120) is used to be electrically connected to the battery cell (500).

9. The laser enhanced contact optimization device according to claim 8, characterized in that: The electrode (120) comprises a main line and a plurality of sub-lines connected to the main line; The main line is electrically connected to the power source, and the sub-line is used to be electrically connected to the grid line of the battery cell (500).

10. A method for optimizing ohmic contacts of solar cells, characterized in that: The laser enhanced contact optimization device according to any one of claims 1 to 9 is used to perform laser enhanced contact optimization on a cell of a solar cell, and the solar cell ohmic contact optimization method comprises: Placing the battery cell on the carrier assembly; Using a cooling component to cool the battery cell so that the temperature of the battery cell reaches a preset temperature; A laser component is used to project a shaped light spot onto the battery cell, and a carrier component is used to apply a reverse bias voltage to the battery cell.

11. The method for optimizing ohmic contact of a solar cell according to claim 10, characterized in that: The preset temperature T satisfies the condition: 5℃≤T≤50℃。 12. The method for optimizing ohmic contact of a solar cell according to claim 10, characterized in that: The step of using a laser component to project a shaped light spot onto the cell specifically includes: In a dark field environment, the laser assembly is used to project a shaped light spot onto the cell; The dark field environment is an environment with a light intensity less than 10 W / m 2 .

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