CN116564839A - A kind of test method of solar battery unit - Google Patents

Abstract

The invention provides a test method for a solar battery unit, which belongs to the field of photovoltaic technology; the test method can solve the problems of probe row shading, conversion efficiency distortion and the like when the solar battery is tested by a traditional pressure measurement method, and reduces the difficulty of battery testing; The above test method can avoid the problem that the actual power generation performance of the battery in the same module is different due to welding and other processes after the battery is divided into bins, ensure that the electrical performance of each unit is closer, and can effectively reduce the risk of component mismatch; The screening of solar battery unit structure and comprehensive monitoring of battery welding conditions have good application value.

Description

A kind of test method of solar battery unit

technical field

The invention belongs to the technical field of photovoltaics, and in particular relates to a testing method for a solar cell unit.

Background technique

Silicon wafers undergo a series of processes such as texturing and diffusion to obtain finished batteries. The differences in silicon wafers and unstable factors in the production process may lead to greater differences in the electrical performance of batteries in the same batch. Therefore, it is necessary to test the batteries and follow the The actual conversion efficiency of the battery is graded to meet the subsequent production and sales requirements of the module.

Currently commonly used batteries mainly include MBB batteries, busbar-free batteries, batteries with special structures including shingled batteries, and new batteries with grooves embedded in metal paste. However, traditional solar cell testing generally gathers photogenerated current through the pressure test busbar, and the number of probe rows cannot increase arbitrarily with the increase in the number of busbars due to the shading of the probe row. At least a few main grids that are pressed by the probes will cause the transmission path of the photo-generated current to become longer and the line loss will increase, which will lead to distortion of the electrical performance data obtained by the test. The busbar-free battery has no busbar, so it is impossible to achieve test sorting through the conventional busbar pressure test method, and the solution of contacting the battery fine grid through the probe row may increase the test instability, and the fluctuation of FF and series resistance becomes larger. It is difficult to realize the direct testing and sorting of battery slices; the non-contact testing method is limited by the accuracy of the sensor, and it is temporarily impossible to realize the effective sorting test of the battery without bus bar. Moreover, traditional testing methods cannot guarantee the electrical performance consistency of multiple small pieces of shingled cells after cutting, which leads to an increased risk of component mismatch.

In addition, the traditional component manufacturing process can reduce the power loss caused by component mismatch due to battery mixing. However, in battery welding and other processes, due to slight exposure, virtual soldering, different degrees of shading, and flux crystallization and other abnormalities, the difference in actual power generation performance of the battery after these processes will intensify, resulting in the power generated by mismatching components. The loss is further increased.

Therefore, it is necessary to develop a test method for solar cell units aiming at the deficiencies of the prior art.

Contents of the invention

Aiming at the deficiencies in the prior art, the present invention provides a test method for a solar cell unit; the test method can solve problems such as shading of probe rows and distortion of conversion efficiency when solar cells are tested by traditional pressure measurement methods, and reduce the battery capacity. Difficulty of the test; the test method can avoid the problem that the actual power generation performance of the battery in the same component is different due to welding and other processes after the battery is divided into bins, and ensure that the electrical performance of each unit is closer, which can effectively reduce the risk of component mismatch; the test The method realizes the screening of solar battery cell structure and comprehensive monitoring of battery welding conditions, which has good application value.

The present invention achieves the above-mentioned technical purpose through the following technical means.

The invention provides a test method for a solar battery unit, which includes: using the metal wire or bus bar of the solar battery unit as the power-taking point, the photo-generated current generated by the solar battery unit is collected from the power-taking point, and then conducted to the The data collector calculates the electrical performance data of the battery unit through the software control system.

Preferably, the steps of the test method are:

Place the solar battery unit in the loading box of the loading unit, and the loading robot will transfer the solar battery unit to the transmission mechanism, and the solar battery unit will be transmitted to the test position of the test system unit through the transmission mechanism, and the solar battery unit will be sent to the After specifying the test position, the upper power-taking unit and the lower power-taking unit move from the standby point to the clamping point, and form good contact with the metal wire or the surface of the bus bar of the solar cell unit; The collected data is transmitted to the data collector through four wires, and then the electrical performance data of the battery unit is calculated by the software control system;

After the test is completed, the upper power-taking unit and the lower power-taking unit return to the standby position, the solar battery unit is transferred to the binning unit by the transmission mechanism, and the sheet-feeding manipulator sorts the battery unit into different material boxes according to the gear setting of the control system Inside, complete the test.

Preferably, the upper material box includes a material box for solar cell testing, a partition type material box or other structural material boxes.

Preferably, the loading robot transfers the battery cells to the conveying mechanism by means of vacuum suction or grasping.

Preferably, when there is a bus bar on the front of the solar battery unit, the upper power-taking unit includes a probe row of the upper power-taking unit and a probe-row bracket of the upper power-taking unit connected thereto;

The lower power-taking unit includes a conductive metal plate, a plurality of vacuum holes are provided on the top of the conductive metal plate, an insulating pad is provided on the top edge of the conductive metal plate, and a vacuum valve interface is provided on the side of the conductive metal plate; An insulating sealing layer is arranged under the plate, and a bottom bracket is arranged under the insulating sealing layer.

Preferably, during the test, the probe row of the upper power harvesting unit is in contact with the bus bar of the solar battery unit, and the bus bar is located above the insulating pad of the lower power harvesting unit.

Preferably, when there are bus bars on both sides of the solar battery unit, the upper power-taking unit includes a support for the upper power-taking unit, and the two sides of the support for the upper power-taking unit are respectively provided with probe rows for the upper power-taking unit. And the insulation pressing block of the upper power-taking unit;

The lower power-taking unit includes a lower power-taking unit support, and the two sides of the lower power-taking unit support are respectively provided with lower power-taking unit probe rows and lower power-taking unit insulating pressing blocks, and the lower power-taking unit probes A lower power-taking unit battery bearing platform is provided between the row and the lower power-taking unit insulation pressing block;

The position of the probe row of the lower power-taking unit corresponds to the insulating pressing block of the upper power-taking unit, and the position of the probe row of the upper power-taking unit corresponds to the insulating pressing block of the lower power-taking unit.

Preferably, when the solar battery unit is tested, the probe row of the upper power-taking unit and the insulating pressing block of the lower power-taking unit clamp the upper bus bar in the middle when the probe row of the lower power-taking unit is in the clamping position, and the probe row of the lower power-taking unit When the insulation pressing block of the upper power-taking unit is in the clamping position, the lower bus bar is clamped in the middle.

Preferably, the structure of the solar battery unit includes: a structure with a grid structure extending over the cell area and a current collecting structure perpendicular to the grid structure at the edge or outside of the battery.

Preferably, the fine grid structure is made of metal paste or metal wires.

Preferably, the current collecting structure is made of metal paste or metal wire.

Compared with prior art, the beneficial effect of the present invention is that

The test method for the solar battery unit of the present invention is applicable to batteries or battery units that have a fine grid structure all over the battery area on the front or both sides and have a current collection structure perpendicular to the fine grid structure on the edge or outside of the battery, wherein the battery The cell type of the cell can be freely selected from PERC, TopCon, HJT, IBC and other types of cells, and also includes single/double-sided cells using patterns such as no busbar, multi-busbar, and shingled on this basis, which has a wide range of applications.

The test method of the present invention can test the new solar cell unit formed by the combination of solar cells and metal wires. The power-taking point of the test method is not on the silver grid on the surface of the battery as in conventional battery testing, but on the metal grid connected to the battery. On the wire; the method directly samples the electrical performance data in the edge of the battery or the external current collection structure, avoiding the interference of the sampling device on the light intensity in the standard light intensity test, and the test result is more accurate.

The test method of the present invention directly tests the solar battery unit, which can simultaneously realize the comprehensive test and sorting of the battery’s own characteristics and welding conditions, and simplify the assembly process; the test and sorting of the solar battery unit by the method can avoid the battery from In welding and other processes, the difference in actual power generation performance is intensified due to various process abnormalities, which makes the electrical performance of each power generation unit of the component closer and reduces the risk of component mismatch.

Description of drawings

Figure 1 is a schematic diagram of the structure of a solar cell unit, in which (a)~(b) are single-sided solar cell units with only one bus bar; (c)~(d) are double-sided solar cell units with only one bus bar .

Fig. 2 is three views of the lower power-taking unit for testing the solar cell unit structure with only one bus bar, in which (a) is a top view, (b) is a main view, and (c) is a left view.

Fig. 3 is a structural schematic diagram of an upper power-taking unit for testing a solar cell unit structure with only one bus bar.

FIG. 4 is a schematic diagram of testing a single-sided solar cell unit with only one bus bar.

Figure 5 is a bifacial solar cell unit with two bus bars.

Fig. 6 is a schematic structural diagram of the upper and lower power-taking units used for testing the upper and lower bus bars.

FIG. 7 is a schematic structural diagram of a double-sided solar cell unit with two bus bars during testing.

Reference signs:

1-solar cell; 2-front wire; 3-back wire; 4-bus bar; 5-vacuum hole; 6-conductive metal plate; 7-bottom bracket; 8-vacuum valve interface; 9-insulation seal layer; 10-insulation pad; 11-probe row of the upper power-taking unit; 12-probe row bracket of the upper power-taking unit; 13-insulation block of the upper power-taking unit; 14-support of the upper power-taking unit; Electric unit insulation pressing block; 16-lower power-taking unit probe row; 17-bottom power-taking unit bracket; 18-lower power-taking unit battery bearing platform.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

Example 1

The invention provides a test method for a solar battery unit, comprising: placing the solar battery unit in the loading box of the loading unit, the loading manipulator transfers the solar battery unit to the transmission mechanism, and transfers the solar battery unit to the transmission mechanism through the transmission mechanism. Transfer to the test position of the test system unit. After the solar battery unit is sent to the designated test position, the upper power-taking unit and the lower power-taking unit move from the standby point to the clamping point, and the surface of the metal wire or bus bar 4 of the solar battery unit Form a good contact; the photo-generated current generated by the solar battery unit is collected from the power-taking point and transmitted to the data collector through four wires, and then the software control system calculates the electrical performance data of the battery unit; after the test is completed, the power-taking unit and The lower power-taking unit returns to the stand-by position, the solar battery unit is transferred to the binning unit by the transmission mechanism, and the sheet-feeding manipulator sorts the battery unit into different material boxes according to the gear setting of the control system to complete the test. In a specific implementation process, the loading box includes a solar cell testing box, a partitioned box or other structural boxes; the loading robot transfers the battery cells to the delivery mechanism by means of vacuum adsorption or grabbing.

As shown in Figures 1 to 4, when only the front side of the solar cell unit has a bus bar 4, the upper power-taking unit includes a probe row 11 of the upper power-taking unit and a probe-row bracket 12 of the upper power-taking unit connected thereto; The lower power-taking unit includes a conductive metal plate 6, a plurality of vacuum holes 5 are provided on the top of the conductive metal plate 6, an insulating pad 10 is provided on the top edge of the conductive metal plate 6, and a vacuum valve is provided on the side of the conductive metal plate 6 An interface 8 ; an insulating sealing layer 9 is provided below the conductive metal plate 6 , and a bottom bracket 7 is provided below the insulating sealing layer 9 . During the test, the probe row 11 of the upper power-taking unit is in contact with the bus bar 4 of the solar battery unit, and the bus bar 4 is located above the insulating pad 10 of the lower power-taking unit.

In the specific implementation process, since the probe row 11 of the upper power-taking unit is not used to test the main grid of the solar cell, but contacts the metal wire/bus bar 4 of the solar cell unit, the coating requirements on the surface of the probe can be appropriately reduced. The contact resistance can meet the test requirements. And because there is only one probe row 11 of the upper power-taking unit, the shading is greatly improved compared with the conventional battery test. When the battery unit structure is such that the bus bars are arranged outside the battery area, the probe row 11 of the upper power-taking unit of the upper power-taking unit is also arranged outside the battery area, without shielding the battery itself. Therefore, compared with the traditional solar cell test, which needs to calculate the shading area of the probe row (large), and then convert the shading to obtain the actual efficiency of the battery, this test method may cause less influence on the distortion of electrical performance data.

In the specific implementation process, the lower power-taking unit is designed as a conductive metal plate that can absorb vacuum. The metal material of the lower power-taking unit that directly contacts the back electrode/back metal wire of the battery unit requires good electrical conductivity and low contact resistance (such as copper). A certain number of vacuum suction holes 5 are opened on the upper surface of the conductive metal plate 6, which are used to absorb the battery unit at the moment of the test, so as to ensure that the battery back electrode/back wire of the battery unit is in good contact with the conductive metal plate 6. The size of the vacuum hole 5 , the number of openings, and the distribution of the holes are determined by the flow rate required for different sizes of the adsorption battery cells. The bottom bracket 7 requires insulation, and is assembled on the same bracket as the upper power-taking unit. Since the upper power-taking unit compresses the battery area by only one bus bar 4, there is even no pressure on the battery area of the battery unit at all. Therefore, it is necessary to ensure that the back of the battery can fully contact the lower power-taking unit, and the vacuum can meet the requirements in a state of less pressure/no pressure.

As shown in Figures 5 to 7, when there are bus bars 4 on both sides of the solar battery unit, the upper power-taking unit includes an upper power-taking unit support 14, and the two sides of the upper power-taking unit support 14 are respectively provided with There are probe rows 11 of the upper power-taking unit and insulating pressing blocks 13 of the upper power-taking unit; the lower power-taking unit includes a lower power-taking unit support 17, and lower power-taking The unit probe row 16 and the lower power-taking unit insulation pressing block 15, and the lower power-taking unit battery bearing platform 18 is arranged between the lower power-taking unit probe row 16 and the lower power-taking unit insulation pressing block 15; The position of the probe row 16 of the power-taking unit corresponds to the insulating pressing block 13 of the upper power-taking unit, and the position of the probe row 11 of the upper power-taking unit corresponds to the insulating pressing block 15 of the lower power-taking unit. When testing the solar battery unit, the upper bus bar is clamped between the upper bus bar when the probe row 11 of the upper power-taking unit and the insulating pressing block 13 of the lower power-taking unit are in the clamping position, and the probe row of the lower power-taking unit 16 and the insulating pressing block 15 of the upper power-taking unit clamp the lower bus bar in the middle when they are in the clamping position.

In the specific implementation process, when the probe row 11 of the upper power-taking unit and the insulating pressing block 15 of the lower power-taking unit are in the clamping position, the upper bus bar 4 is tightly clamped in the middle, so that the load generated by the battery unit under the standard light intensity The current is conducted to the upper power-taking unit through the bus bar 4 . When the probe row 16 of the lower power-taking unit and the insulating pressing block 13 of the upper power-taking unit are in the clamping position, the lower bus bar 4 is tightly clamped in the middle, so that the carriers generated by the battery unit under the standard light intensity pass through the bus bar 4 conduct to the lower power-taking unit.

In this embodiment, the structure of the solar cell unit includes: a fine grid structure throughout the cell area or a current collecting structure perpendicular to the fine grid structure at the edge or outside of the battery. Wherein, the fine grid structure is made of metal paste or metal wire; the structure for collecting current is made of metal paste or metal wire.

Example 2

When testing the solar battery unit structure shown in Figure 1(a)~(d), when the above-mentioned solar battery units reach the designated test position of the test system unit, the upper power-taking unit moves from the standby point to the clamping point position, the vacuum of the lower power-taking unit is turned on, and the solar simulator starts to work. The upper and lower power-taking units collect the light-generated current of the battery unit by contacting the battery unit metal wire or the bus bar 4, and transmit it to the data collector. The software control system calculates the battery current. The electrical performance data of the unit. After obtaining the electrical performance parameters, the upper power-taking unit returns to the standby position, and the lower power-taking unit vacuums and closes. The battery cell is transferred to the next cell by the transfer mechanism. Among them, the positions of the standby point and the clamping point, the degree of vacuum suction, etc. can be set according to actual needs. When the upper and lower power-taking units are at the clamping point, it is necessary to ensure that the upper power-taking unit is in good contact with the bus bar 4 of the battery unit, and that the lower power-taking unit is in good contact with the battery back electrode/back wire 3 of the battery unit, so that The photo-generated current can be transmitted from the battery unit to the power-taking unit.

Example 3

When testing the structure of the solar battery unit shown in Figure 5, the battery unit reaches the designated test position of the test system unit, and the upper and lower power-taking units move from the position of the standby point to the position of the clamping point. The positions of the standby point and the clamping point can be set as required parameter. However, when the upper and lower power-taking units are at the clamping point, it is necessary to ensure that the upper and lower power-taking units are in good contact with the bus bars 4 above and below the solar cell unit, so that the photo-generated current can be transmitted from the battery unit to the power-taking unit to complete collection. After the upper and lower power extraction units are in place, the solar simulator starts to work. The upper and lower power acquisition units collect the photogenerated current of the battery unit and transmit it to the data collector. The software control system calculates the electrical performance data of the battery unit. After obtaining the electrical performance parameters, the upper and lower power-taking units return to the standby position, and the battery unit is transferred to the next unit by the transfer mechanism.

The described embodiment is a preferred implementation of the present invention, but the present invention is not limited to the above-mentioned implementation, without departing from the essence of the present invention, any obvious improvement, replacement or modification that those skilled in the art can make Modifications all belong to the protection scope of the present invention.

Claims (10)

1. A test method for a solar cell unit, characterized in that, comprising: taking the metal wire or the bus bar (4) of the solar cell unit as the power-taking point, the photo-generated current produced by the solar cell unit is collected from the power-taking point, and then It is transmitted to the data collector through four wires, and then the electrical performance data of the battery unit is calculated by the software control system. 2. the testing method of solar cell unit according to claim 1, is characterized in that, described testing method is: Place the solar battery unit in the loading box of the loading unit, and the loading robot will transfer the solar battery unit to the transmission mechanism, and the solar battery unit will be transmitted to the test position of the test system unit through the transmission mechanism, and the solar battery unit will be sent to the After specifying the test position, the upper power-taking unit and the lower power-taking unit move from the standby point to the clamping point, and form good contact with the surface of the metal wire or bus bar (4) of the solar battery unit; then the photo-generated current generated by the solar battery unit is from The power point is collected and transmitted to the data collector through four wires, and then the software control system calculates the electrical performance data of the battery unit; After the test is completed, the upper power-taking unit and the lower power-taking unit return to the standby position, the solar battery unit is transferred to the binning unit by the transmission mechanism, and the sheet-feeding manipulator sorts the battery unit into different material boxes according to the gear setting of the control system Inside, complete the test. 3 . The method for testing a solar cell unit according to claim 2 , wherein the loading box includes a solar cell testing box, a partitioned box or other structural boxes. 4 . 4 . The method for testing solar battery units according to claim 2 , wherein the loading manipulator transfers the battery units to the transfer mechanism by means of vacuum adsorption or grasping. 5. The method for testing a solar battery unit according to claim 2, characterized in that, when there is a bus bar (4) on the front of the solar battery unit, the upper power-taking unit includes a probe row (11 ) and the probe row bracket (12) connected to it; The lower power-taking unit includes a conductive metal plate (6), a plurality of vacuum suction holes (5) are provided on the top of the conductive metal plate (6), and an insulating pad (10) is provided on the top edge of the conductive metal plate (6), A vacuum valve interface (8) is provided on the side of the conductive metal plate (6); an insulating sealing layer (9) is provided under the conductive metal plate (6), and a bottom bracket (7) is provided under the insulating sealing layer (9). ). 6. The method for testing a solar battery unit according to claim 5, characterized in that, during the test, the probe row (11) of the upper power-taking unit of the upper power-taking unit is in contact with the bus bar (4) of the solar battery unit, so The bus bar (4) is located above the insulating pad (10) of the lower power-taking unit. 7. The method for testing solar battery units according to claim 2, characterized in that, when there are bus bars (4) on both sides of the solar battery unit, the upper power-taking unit includes an upper power-taking unit bracket ( 14), the two sides of the upper power-taking unit bracket (14) are respectively provided with the upper power-taking unit probe row (11) and the upper power-taking unit insulating pressing block (13); The lower power-taking unit includes a lower power-taking unit support (18), and the two sides of the lower power-taking unit support (18) are respectively provided with lower power-taking unit probe rows (16) and lower power-taking unit insulating pressing blocks (15), the battery bearing platform (18) of the lower power-taking unit is provided between the probe row (16) of the lower power-taking unit and the insulating pressing block (15) of the lower power-taking unit; The position of the probe row (16) of the lower power-taking unit corresponds to the insulating press block (13) of the upper power-taking unit, and the position of the probe row (11) of the upper power-taking unit corresponds to the insulating press block (15) of the lower power-taking unit . 8. The method for testing a solar battery unit according to claim 7, characterized in that, when testing a solar battery unit, the probe row (11) of the upper power-taking unit and the insulating pressing block (15) of the lower power-taking unit The upper bus bar (4) is sandwiched in the clamping position, and the probe row (16) of the lower power-taking unit and the insulating pressing block (13) of the upper power-taking unit are in the clamping position to clamp the lower bus bar (4) Sandwiched in the middle. 9. The method for testing a solar cell unit according to claim 2, wherein the structure of the solar cell unit comprises: a fine grid structure throughout the cell area and a confluence perpendicular to the fine grid structure at the edge or outside of the cell The structure of the current. 10 . The method for testing a solar battery unit according to claim 9 , wherein the fine grid structure is made of metal paste or metal wire; and the structure for collecting current is made of metal paste or metal wire. 11 .