Contact means for a solar cell

Abstract

A kind of contact device of solar cell, belong to photovoltaic testing device field, including upper contact and lower contact;Its characterized in that: the upper contact includes transparent support plate and wire group;The wire group includes multiple parallelly arranged wires;The wire group is arranged on the lower surface of the aforementioned transparent support plate;The lower contact includes several parallelly arranged test knives;The top of the test knife is provided with conductive strip;The conductive strip is located on the same horizontal plane.By the structural improvement of existing testing device, the electrical performance test of large size solar cell of multiple main line is realized;The contact device of the utility model has simple structure, is easy to manufacture, is easy to operate, and preparation cost is low, and is suitable for promotion and application.

Description

Technical Field

[0001] This utility model belongs to the field of photovoltaic testing devices, and in particular relates to a contact device for solar cells. Background Technology

[0002] During the production and research and development of solar cells, electrical correlation tests are required to assess their performance. These tests involve applying electricity to the two electrodes of the solar cell or collecting electrical signals at the electrodes for testing. Electrical contact devices are essential in all electrical correlation tests to establish detachable electrical contact with the solar cell under test.

[0003] Conventional solar cells range in size from 156mm to 230mm, with one side being the positive electrode and the other the negative electrode. During testing, the positive and negative electrodes must be contacted separately. In addition, for accurate testing, a Kelvin four-wire system is used, meaning that the positive electrode current and voltage must be collected separately, and the negative electrode current and voltage must be collected separately.

[0004] To achieve higher photoelectric efficiency, solar cells now have a large number of main grid lines, or even without main grid lines but with a large number of pre-installed series solder strips (both main grid lines and series solder strips are collectively referred to as main lines), sometimes as many as 16-40 BB. In current testing, a metal blade corresponding to the solar cell's main lines is commonly used to collect electrical signals from the solar cell's light-receiving surface, while a probe array corresponding to the main lines is used to collect electrical signals from the solar cell's back-light-receiving surface. However, this contact device is no longer suitable for solar cells with a large number of solder strips. This is because the metal blade is generally quite thick, causing severe shading and significantly affecting the solar cell's light reception; simultaneously, the large number of main lines requires a large number of probe arrays, which are expensive, resulting in a very high cost for the contact device. Summary of the Invention

[0005] The present invention aims to solve the above problems and provide a contact device suitable for large-size solar cells with many main wires.

[0006] The contact device for the solar cell of this utility model includes an upper contact and a lower contact.

[0007] The upper contact element includes a transparent support plate and a wire assembly;

[0008] The conductor group includes multiple parallel conductors; the conductor group is disposed on the lower surface of the aforementioned transparent support plate;

[0009] The lower contact includes several parallel test blades; a conductive strip is provided on the top of each test blade; the conductive strips are located on the same horizontal plane.

[0010] During testing of the solar cell under test, the cell is positioned between the upper and lower contacts, which are connected from both sides. Simulated light shines onto the solar cell through a transparent support plate. The wires on the upper contact make electrical contact with the grid lines on the front side of the solar cell, collecting the electrical signal from the light-receiving surface. The conductive strip at the top of the test blade makes electrical contact with the grid lines on the back side of the solar cell, collecting the electrical signal from the back side, thus completing the test. The parallel arrangement of multiple test blades facilitates the removal of any battery fragments and also allows for better coordination with the adsorption claws of automated devices.

[0011] Furthermore, in the contact device for the solar cell described in this invention, the position of the wire corresponds to the position of the main wire of the solar cell under test; the direction of the test blade is consistent with that of the aforementioned wire; and the position of the test blade corresponds to the position of the aforementioned wire. By having the wire and the test blade contact the solar cell under test from the front and back sides respectively, the solar cell under test can be tested.

[0012] Furthermore, in the contact device of the solar cell described in this utility model, the conductor group includes a current conductor group and a voltage conductor group; the conductors in the current conductor group are electrically conductive to each other; the conductors in the voltage conductor group are electrically conductive to each other. By setting up the current conductor group and the voltage conductor group, and ensuring that the conductors in the voltage conductor group are not conductive to the conductors in the current conductor group, a Kelvin four-wire system can be achieved, effectively improving the testing accuracy.

[0013] Furthermore, in the contact device of the solar cell described in this utility model, the number of wires in the current wire group is 1-20 times the number of wires in the aforementioned voltage wire group.

[0014] Furthermore, in the contact device of the solar cell described in this utility model, the distance between the voltage conductor group and the current conductor group is between 0.01-5mm, thereby ensuring the accuracy of voltage acquisition.

[0015] Furthermore, in the contact device of the solar cell described in this utility model, the width of the wire is 0.02mm-2mm. With a large number of wires, the wires of this size result in less shading of the solar cell under test, thus meeting the testing requirements. The thickness of the transparent support plate is 2mm-20mm. During the test, the transparent support plate reflects or absorbs light, but these light losses are uniform and are relatively easy to compensate for.

[0016] Furthermore, in the contact device for the solar cell described in this utility model, several sets of wires are arranged in parallel; several sets of test blades are arranged in parallel corresponding to the sets of wires. The multiple sets of wires arranged in parallel are not electrically connected to each other, and the multiple sets of test blades arranged in parallel are also not electrically connected to each other, allowing for the simultaneous testing of multiple solar cells and effectively improving testing efficiency.

[0017] Furthermore, in the contact device of the solar cell described in this invention, a strip-shaped hole is formed on the transparent support plate. This allows an infrared thermometer to collect infrared radiation from the solar cell under test during testing, enabling infrared temperature measurement.

[0018] Furthermore, in the contact device for the solar cell described in this utility model, the test blade is fixedly mounted on the base plate. This unified mounting of the test blades on the base plate facilitates replacement according to the requirements of the main line of the solar cell under test, improving operational efficiency. The conductive strips at both ends of the test blade are designed in an arc shape, effectively preventing breakage of the conductive strips due to deformation of the test blade during testing.

[0019] Furthermore, in the contact device of the solar cell described in this utility model, the base plate is provided with several slots or grooves for fixing the test blades. By providing slots or grooves, the test blades can be fixed more easily; it also facilitates adjusting the spacing of the test blades according to the main line of the solar cell module under test, so as to quickly adapt to solar cells under test with different main lines.

[0020] The contact device for solar cells described in this utility model includes an upper contact and a lower contact. The upper contact includes a transparent support plate and a wire assembly. The lower contact is a test blade structure. By improving the structure of existing testing devices, the electrical performance testing of large-size solar cells with multiple main lines can be achieved. The contact device described in this utility model has a simple structure, is easy to manufacture, convenient to operate, and has low manufacturing cost, making it suitable for widespread application. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the upper contact member structure according to an embodiment of the present utility model;

[0022] Figure 2 This is a schematic diagram of the contact device structure of the solar cell according to an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the test knife structure described in an embodiment of the present utility model;

[0024] Figure 4 This is a schematic diagram of the upper contact member structure according to an embodiment of the present utility model;

[0025] Among them, 1-transparent support plate, 2-first wire group, 3-current wire group, 4-voltage wire group, 5-strip hole, 6-second wire group, 7-first test blade group, 8-base plate, 9-second test blade group, 10-conductive strip, 11-flexible strip, 12-test blade. Detailed Implementation

[0026] The contact device for the solar cell of this utility model will be described in detail below with reference to the accompanying drawings and embodiments.

[0027] This embodiment discloses a contact device for a solar cell, including an upper contact and a lower contact; such as Figure 1 As shown, the upper contact includes a transparent support plate 1 and a wire assembly; the wire assembly includes multiple parallel wires; the wires correspond to the main wires of the solar cell under test; the wire assembly is disposed on the lower surface of the aforementioned transparent support plate 1; the lower contact includes several parallel test blades 12; a conductive strip 10 is disposed on the top of each test blade 12; the conductive strip 10 is located on the same horizontal plane. The test blades 12 are aligned with the direction of the aforementioned wires; the position of the test blades 12 corresponds to the position of the aforementioned wires.

[0028] In this embodiment, the conductor group includes a current conductor group 3 and a voltage conductor group 4; the conductors within the conductor group are electrically conductive to each other, while the conductors in the voltage conductor group 4 are not conductive to the conductors in the current conductor group 3, thus achieving a Kelvin four-wire test. The test blade 12 is fixedly mounted on the base plate 8. A strip-shaped hole 5 is formed on the transparent support plate 1. In specific applications, the conductors can be any combination of silver wire, copper wire, silver-plated copper wire, gold-plated copper wire, etc.

[0029] In this embodiment, 12mm thick ultra-clear glass is used as the transparent support plate 1, such as... Figure 1 As shown, there are two conductor groups, namely conductor group 2 and conductor group 6, which can test two solar cells simultaneously. Each conductor group includes a current conductor group 3 with 22 conductors and a voltage conductor group 4 with 4 conductors. The number of current conductors is 5.5 times that of voltage conductors. All conductors are on the same plane and are made of 0.3mm silver-plated copper wire. The total shading width is 0.3*(22+4)=7.8mm, which is significantly improved compared to the shading width of a conventional probe array of 3X16=48mm. The conductors are in near-perpendicular contact with the fine grid lines of the solar cell (angle between 80-100 degrees). The voltage conductors in the voltage conductor group and the current conductors in the nearest current conductor group 3 are spaced 1mm apart but are not conductive, ensuring a four-wire system.

[0030] Correspondingly, the test blades 12 used in the lower contact are also provided in two sets, namely the first test blade group 7 and the second test blade group 9. In this embodiment, each group includes 26 blades. The conductive strip 10 at the top of the test blade 12 is provided with a current conductive area and a voltage conductive area; the hardness of the flexible strip 11 at the bottom of the conductive strip 10 is 30; the flexible strip 11 can be selected as a rubber strip, silicone strip, silicone foam strip, hollow latex tube, etc., as needed to ensure that it can deform well so as to achieve good electrical contact between the test blade 12 and the solar cell under test.

[0031] When testing the solar cell under test, such as Figure 2 As shown, the solar cell under test is located between the upper and lower contacts, which contact the solar cell from both sides. Simulated light shines through the transparent support plate 1 onto the solar cell under test. The wires on the upper contact make electrical contact with the grid lines on the front side of the solar cell, collecting the electrical signal from the light-receiving surface of the solar cell. The conductive strip 10 at the top of the test blade 12 makes electrical contact with the grid lines on the back side of the solar cell, collecting the electrical signal from the back side of the solar cell. The 22 current wires on the upper contact, the 4 voltage wires, and the conductive strip 10 on the lower contact are then connected to an external testing system to complete the testing of the solar cell under test.

[0032] In this public example, such as Figure 3 As shown, based on existing technology, the conductive strips 10 at both ends of the test blade 12 are set in an arc shape, with an approximate arc radius of more than 2mm in the bending area. The arc shape can effectively prevent the conductive strips 10 from breaking due to deformation of the test blade 12 during the test.

[0033] In practical applications, multiple test blades 12 can be fixed to a base plate 8, which is relatively simple and easy to implement. Alternatively, multiple test blades 12 can be detachably fixed to the base plate 8, adapting to solar cells with different main lines by replacing different positioning plates. Depending on the specific application, the base plate 8 can also be provided with several slots or grooves for fixing the test blades 12. These slots or grooves facilitate easy connection, repair, and replacement of the test blades 12, and also allow for easy adjustment of the spacing between the test blades 12 according to the main line of the solar cell module under test, thus quickly adapting to solar cells under test with different main lines.

[0034] Meanwhile, in specific applications, the solar cells under test located between the upper and lower contacts can be automatically transported and replaced by setting up a rotating wheel structure and trays. The rotating wheel structure rotates multiple trays one by one to the upper and lower contacts for electrical performance testing, effectively improving testing efficiency.

[0035] Based on the disclosed embodiments, the wire assembly disposed on the transparent support plate 1 in the embodiments can be fixed to the transparent support plate 1 by adhesive / embedding, or it can be disposed on the transparent support plate 1 by means of printing, electroplating, vapor deposition, sputtering conductive materials, etc. Figure 4The diagram shows a implementation using a printed circuit board, featuring two lead groups: a first lead group 2 and a second lead group 6. These include a first current lead group 3, a first voltage lead group 4, a second current lead group 3, and a second voltage lead group 4. This allows for simultaneous testing of two solar cells while maintaining a Kelvin four-wire configuration. Although all lead groups are on the same horizontal plane, the printed circuit board can be layered to ensure that the V+ and I+ signals of the first solar cell and the second solar cell can be acquired independently.

Claims

1. A contact device for a solar cell, comprising an upper contact and a lower contact; characterized in that: The upper contact element includes a transparent support plate and a wire assembly; The conductor group includes multiple parallel conductors; the conductor group is disposed on the lower surface of the aforementioned transparent support plate; The lower contact includes several parallel test blades; a conductive strip is provided on the top of each test blade; the conductive strips are located on the same horizontal plane.

2. The contact device for the solar cell according to claim 1, characterized in that: The position of the wire corresponds to the position of the main wire of the solar cell under test; the direction of the test blade is consistent with that of the aforementioned wire; the position of the test blade corresponds to the position of the aforementioned wire.

3. The contact device for the solar cell according to claim 1 or 2, characterized in that: The conductor group includes a current conductor group and a voltage conductor group; the conductors in the current conductor group are electrically conductive to each other; the conductors in the voltage conductor group are electrically conductive to each other.

4. The contact device for the solar cell according to claim 3, characterized in that: The number of conductors in the current conductor group is 1 to 20 times the number of conductors in the aforementioned voltage conductor group.

5. The contact device for the solar cell according to claim 4, characterized in that: The distance between the voltage conductor group and the current conductor group is between 0.01 and 5 mm.

6. The contact device for the solar cell according to claim 3, characterized in that: The width of the conductor is 0.02mm-2mm; the thickness of the transparent support plate is 2mm-20mm.

7. The contact device for the solar cell according to claim 3, characterized in that: Several sets of wires are arranged side by side; several sets of test blades are arranged side by side corresponding to the sets of wires.

8. The contact device for the solar cell according to claim 7, characterized in that: The transparent support plate has strip holes.

9. The contact device for the solar cell according to claim 8, characterized in that: The test blade is fixedly mounted on the base plate; the conductive strips at both ends of the test blade are arc-shaped.

10. The contact device for the solar cell according to claim 9, characterized in that: The base plate is provided with several slots or grooves for fixing the test blade.

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