Electric contact test knife of solar cell

Abstract

An electric contact test knife for a solar cell belongs to the field of solar cell test devices and is characterized by comprising a knife body, a flexible strip and a conductive strip, the cutter body is arched; fixing holes are formed in the two ends of the cutter body; the flexible strip is arranged at the top of the cutter body; the conductive strip is arranged on the flexible strip, and the flexible strip is located between the conductive strip and the cutter body. A conductive strip and a flexible strip are sequentially arranged at the top of an arched test knife from top to bottom, the conductive strip is used for being in contact with a to-be-tested solar cell to collect electric signals, and the flexible strip is used for being deformed when the conductive strip is in contact with the to-be-tested solar cell, so that the contact surface of the conductive strip and the to-be-tested solar cell is increased; the device provides stable and reliable contact, reduces the possibility that the solar cell to be tested is fragile, does not need to be adjusted when testing the solar cell modules to be tested with different main grid numbers, is simple in structure, is easy to operate, is low in manufacturing and later maintenance cost, and is suitable for popularization and application.

Description

Technical Field

[0001] The utility model belongs to the field of solar cell testing devices, in particular to an electric contact testing knife for solar cells. Background Art

[0002] A solar cell is a thin semiconductor sheet that can generate electricity through the photovoltaic effect when exposed to light. The generated current is collected and conducted through the grid lines. During the production and development process, it is necessary to conduct electrical tests on the performance of solar cells. During the test, it is necessary to apply power to the two poles of the solar cell, or to collect electrical signals at the two poles of the solar cell for related tests. Electrical contact devices are required in all electrical tests to form detachable electrical contact with the solar cell to be tested.

[0003] Conventional solar cells generally have a positive electrode on one side and a negative electrode on the other side, and the positive and negative electrodes need to be in contact separately. The grid lines on the surface of solar cells are in various forms. But they can be mainly divided into MBB grid lines and 0BB grid lines. The main body of the MBB grid line is a large number of parallel thin grid lines, and then a number of main grid lines and series thin grid lines are used to form a cross; the number of main grid lines M ranges from 2 to 20; the main body of the 0BB grid line is a large number of parallel thin grid lines, but there is no main grid line.

[0004] For MBB-type gate lines, existing testing solutions generally use upper and lower probe rows for electrical contact and testing. However, when testing different numbers of main gates, the probe rows need to be adjusted, which is time-consuming and labor-intensive. For 0BB-type gate lines, existing testing solutions have problems such as fragility, unreliable contact, and complex and costly testing equipment. Summary of the invention

[0005] The utility model aims to solve the above-mentioned problem and provides an electric contact test knife for solar cells which is compatible with both MBB-type and 0BB-type grid lines.

[0006] The solar cell electrical contact test knife of the utility model comprises a knife body, a flexible strip and a conductive strip;

[0007] The knife body is in a bow shape;

[0008] Both ends of the knife body are provided with fixing holes;

[0009] The flexible strip is arranged on the top of the aforementioned knife body;

[0010] The conductive strip is arranged on the flexible strip, and the flexible strip is located between the conductive strip and the blade body.

[0011] During the test, the blade body is fixed on the test device through the fixing holes at both ends. After the conductive strip is in electrical contact with the solar cell to be tested, the blade body provides support, and the flexible strip between the blade body and the conductive strip undergoes elastic deformation, thereby ensuring good and reliable contact between the conductive strip and the solar cell to be tested, and then reliably and stably collecting electrical signals during the test.

[0012] Furthermore, the solar cell electrical contact test knife of the utility model also includes a film;

[0013] The film wraps the aforementioned flexible strip and is fixedly arranged on the knife body;

[0014] The film is located between the conductive strip and the flexible strip. By arranging the film to wrap the flexible strip, the flexible strip is more firmly fixed, and while reducing left-right twisting and swinging, the flexible strip is further protected.

[0015] Furthermore, in the solar cell electrical contact test knife of the utility model, a groove is provided on the top of the knife body; the lower end of the flexible strip is clamped in the groove. By providing the groove, the flexible strip is clamped in the groove, and the connection is more stable and firm, and it is not easy to slide out or separate from the knife body, thereby improving the test accuracy and service life of the test knife.

[0016] Furthermore, in the solar cell electrical contact test knife of the utility model, the conductive strip is provided with two conductive areas; the two conductive areas are insulated and provided with two conductive areas, which are respectively used to collect voltage and current signals, thereby realizing Kelvin four-wire collection.

[0017] Furthermore, in the solar cell electrical contact test knife of the utility model, two sections of conductive strips are symmetrically arranged on the knife body.

[0018] Furthermore, the solar cell electrical contact test knife of the utility model has a knife body with a length of 10-50 cm, a thickness of 0.5-10 mm, and a height of 1-100 mm.

[0019] Furthermore, in the solar cell electrical contact test knife of the utility model, the thickness of the film is 0.01-2 mm.

[0020] Furthermore, in the solar cell electrical contact test knife of the utility model, the conductive strip is an FPC flexible printed circuit board or a wire; the diameter of the wire is 0.05-2mm. The conductive strip is made by using mature printed circuit board technology, which is inexpensive, high-precision, beautiful and durable.

[0021] Furthermore, in the solar cell electrical contact test knife of the utility model, a tail wire and a contact terminal are arranged on the knife body; by presetting the tail wire and the contact terminal, the electrical signal collected by the conductive strip can be conveniently introduced into the external processor, thereby improving the test efficiency.

[0022] The electrical contact test knife for solar cells of the utility model is provided with a conductive strip and a flexible strip in sequence from top to bottom on the top of the bow-shaped test knife. The conductive strip is used for contacting the solar cell to be tested to collect electrical signals. The flexible strip is used for deforming when the conductive strip contacts the solar cell to be tested, thereby increasing the contact surface between the conductive strip and the solar cell to be tested, providing stable and reliable contact, while limiting the occurrence of fragility of the solar cell to be tested. No adjustment is required when testing solar cell modules to be tested with different numbers of main grids. The utility model has a simple structure, is easy to operate, has low manufacturing and later maintenance costs, and is suitable for popularization and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a front view of the electrical contact test blade structure of the solar cell described in the first embodiment of the utility model;

[0024] Figure 2 A top view of the electrical contact test blade structure of the solar cell described in Example 1 of the utility model;

[0025] Figure 3 This is a schematic diagram of the structure of the tail wire and the contact terminal according to the first embodiment of the utility model;

[0026] Figure 4 A schematic diagram of a structure in which two conductive regions are arranged on the conductive strip according to the first embodiment of the utility model;

[0027] Figure 5 This is a schematic diagram of the structure of the solar cell electrical contact test knife according to the second embodiment of the utility model;

[0028] Figure 6 This is a schematic diagram of the structure of the solar cell electrical contact test knife according to the third embodiment of the present utility model;

[0029] Figure 7 This is a schematic diagram of the structure of the solar cell electrical contact test knife according to the fourth embodiment of the utility model;

[0030] Among them, 1-conductive strip, 2-flexible strip, 3-knife body, 4-fixing hole, 5-film, 6-voltage collection area, 7-current collection area, 8-glass, 9-solar cell to be tested, 10-negative electrode test knife, 11-positive electrode test knife. DETAILED DESCRIPTION

[0031] The electrical contact test knife for solar cells of the utility model is described in detail below through the accompanying drawings and embodiments.

[0032] Embodiment 1

[0033] This embodiment discloses a solar cell electrical contact test knife, such as Figure 1 , Figure 2 As shown, it includes a blade body 3, a flexible strip 2 and a conductive strip 1; the blade body 3 is bow-shaped; fixing holes 4 are provided at both ends of the blade body 3; the flexible strip 2 is provided on the top of the aforementioned blade body 3; the conductive strip 1 is provided on the aforementioned flexible strip 2, and the flexible strip 2 is located between the conductive strip 1 and the blade body 3.

[0034] In the disclosed embodiment, the blade body 3 is 37.2 cm long, 9 mm thick, and 45 mm high. The length of the blade body 3 is about 1.5 times the length of the solar cell 9 to be tested. If the thickness is too thin, it is easy to bend. If the thickness is too thick, the distance between the blade bodies 3 arranged in parallel is too large, and the electrical signal cannot be collected well. In this embodiment, two sections of conductive strips 1 are symmetrically arranged on the blade body 3. The two independent conductive strips 1 are independently arranged on the blade body 3 and are located at the same height. Each section of conductive strip 1 is electrically in contact with a solar cell respectively, and the conductive strip 1 and the blade body 3 are insulated. The flexible strip 2 and the blade body 3, and the conductive foil and the flexible strip 2 are all bonded with cloth-based tape. In specific applications, the blade body 3 can be made of metal, POM, phenolic resin and other materials, or can be made of hard PCB.

[0035] In the disclosed embodiment, a groove is provided on the top of the knife body 3, and the groove depth is 1mm; the lower end of the flexible strip 2 is clamped in the groove, so that the flexible strip 2 is clamped in the groove, and the connection is more stable and firm, and it is not easy to slip out or separate from the knife body 3, thereby improving the test accuracy and service life of the test knife. The size of the flexible strip 2 is 3X3mm, and the length is 99mm, which is consistent with the length of the installation part of the knife body 3. Figure 4 As shown, the conductive strip 1 is provided with two conductive areas; the two conductive areas are insulated. In the embodiment of the present disclosure, the conductive strip 1 is an FPC flexible printed circuit board, and the two conductive areas include a voltage collection area 6 and a current collection area 7 (the current collection area 7 has a larger area because current flows through it), which are respectively used to collect voltage and current signals to realize Kelvin four-wire collection.

[0036] like Figure 3 As shown, the blade body 3 is provided with tail wires and contact terminals, including voltage wires and voltage contact terminals, current wires and current contact terminals, and the contact terminals are 4mm banana plugs. By presetting the tail wires and contact terminals, the electrical signals collected by the conductive strip 1 can be conveniently introduced into the external processor to improve the test efficiency.

[0037] When testing, the test knife is fixed on the test device by passing the bolt through the fixing hole 4. After the conductive strip 1 is in electrical contact with the solar cell 9 to be tested, the knife body 3 provides support, and the flexible strip 2 between the knife body 3 and the conductive strip 1 undergoes elastic deformation, thereby ensuring that the conductive strip 1 and the solar cell 9 to be tested achieve good and reliable contact, thereby reliably and stably collecting electrical signals during the test. When adjusting or maintaining, the position of the test knife can be adjusted or the test knife can be replaced after loosening the screw.

[0038] Embodiment 2

[0039] Based on the above-mentioned embodiment 1, the solar cell electrical contact test knife described in this embodiment is different from that in embodiment 1 in that it further includes a film 5; the film 5 wraps the aforementioned flexible strip 2 and is fixedly arranged on both sides of the knife body 3 through the two ends of the film 5; the film 5 is located between the conductive strip 1 and the flexible strip 2. In the disclosed embodiment, the film 5 is fixed on the knife body 3 and arranged along the long side of the knife body 3; Figure 5 As shown, the film 5 wraps the flexible strip 2, the film 5 has a thickness of 0.05 mm, and is bonded to the blade 3 by a cloth-based tape. By wrapping the flexible strip 2 with the film 5, the flexible strip 2 is more firmly fixed, and the flexible strip 2 is further protected while reducing left and right twisting and swinging.

[0040] Embodiment 3

[0041] Based on the electrical contact test knife of the solar cell described in the above embodiment 1 or embodiment 2, multiple test knives described in the above embodiments are used, arranged in parallel, and located on one side of the solar cell 9 to be tested. All conductive strips 1 are in a plane and contact a solar cell together. Multiple test knives can improve the contact reliability with the solar cell, reduce the resistance of the electrical signal path, and thus obtain more accurate test results. Multiple test knives can be made fixed as a whole, or the spacing can be adjusted. Figure 6 As shown, two test areas are set at the same time, all the test knives on the left side contact the same solar cell, and all the test knives on the right side contact another solar cell. Two solar cells can be tested at the same time and ensure that they will not interfere with each other, which can significantly improve the test efficiency.

[0042] Embodiment 4

[0043] Based on the electrical contact test blade of the solar cell described in the first or second embodiment, a test blade structure for BC solar cells is disclosed. During the test of the BC solar cell, since the positive and negative electrodes are both located on one side of the solar cell, according to the characteristics of the grid line structure spacing of the BC cell, such as Figure 7As shown, a plurality of the test knives described in the aforementioned embodiments are selected and arranged in parallel to form a positive test knife 11 and a negative test knife 10. The positive test knife 11 collects positive electrical signals, and the negative test knife 10 collects negative electrical signals. According to common knowledge, a transparent support plate is arranged on the other side of the BC solar cell, and glass 8 is used in this embodiment.

[0044] In the process of testing conventional bifacial solar cells, the electrical signal of one side of the solar cell is collected through multiple parallel test blades, and the electrical signal of the other side of the solar cell is collected through a probe row or a wire or a metal strip or a metal table or the test blade described in the above embodiment, thereby realizing the collection of positive and negative signals of the solar cell.

Claims

1. An electrical contact test knife for solar cells, characterized in that: It includes a blade body, a flexible strip and a conductive strip; The knife body is in a bow shape; Both ends of the knife body are provided with fixing holes; The flexible strip is arranged on the top of the aforementioned knife body; The conductive strip is arranged on the flexible strip, and the flexible strip is located between the conductive strip and the blade body.

2. The solar cell electrical contact test knife according to claim 1, characterized in that: Also includes films; The film wraps the aforementioned flexible strip and is fixedly arranged on the knife body; The film is located between the conductive strip and the flexible strip.

3. The solar cell electrical contact test knife according to claim 1 or 2, characterized in that: The top of the knife body is provided with a groove; the lower end of the flexible strip is clamped in the groove.

4. The solar cell electrical contact test knife according to claim 3, characterized in that: The conductive strip is provided with two conductive areas; the two conductive areas are insulated from each other.

5. The solar cell electrical contact test knife according to claim 4, characterized in that: Two sections of conductive strips are symmetrically arranged on the knife body.

6. The solar cell electrical contact test knife according to claim 5, characterized in that: The blade body has a length of 10-50 cm, a thickness of 0.5-10 mm, and a height of 1-100 mm.

7. The solar cell electrical contact test knife according to claim 2, characterized in that: The thickness of the film is 0.01-2 mm.

8. The solar cell electrical contact test knife according to claim 7, characterized in that: The conductive strip is an FPC flexible printed circuit board or a conductive wire; the diameter of the conductive wire is 0.05-2 mm.

9. The solar cell electrical contact test knife according to claim 8, characterized in that: The knife body is provided with a tail wire and a contact terminal.

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