Pressurizing structure for laser-assisted sintering

Abstract

The embodiment of the utility model provides a pressurizing structure for laser-assisted sintering, and relates to the technical field of solar cells, the pressurizing structure comprises a power supply, a plurality of first contact electrodes and a plurality of second contact electrodes, the power supply comprises a positive electrode and a negative electrode, and each first contact electrode comprises a first end and a second end which are opposite to each other; the first ends of the plurality of first contact electrodes are electrically connected with the positive electrode of the power supply, the second ends of the plurality of first contact electrodes are electrically connected with the positive electrode of the power supply, and the plurality of first contact electrodes are used for applying first voltage to the N-region grid line slurry. Each second contact electrode comprises a third end and a fourth end which are opposite to each other, the third ends of the plurality of second contact electrodes are electrically connected with the negative electrode of the power supply, the fourth ends of the plurality of second contact electrodes are electrically connected with the negative electrode of the power supply, and the plurality of second contact electrodes are used for applying a second voltage to the P-region grid line slurry so as to apply a bias voltage to the grid line slurry, the advantages of laser-assisted sintering are better exerted, and the efficiency and performance of the solar cell are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a laser-assisted sintering pressurizing structure. BACKGROUND

[0002] The grid lines of the interdigitated back contact (IBC) cell are arranged on the back surface, and the front surface is not provided with grid lines. Since the front surface is not shielded by the grid lines, the photoelectric conversion rate of the IBC cell is relatively high.

[0003] At present, laser-assisted sintering can be used to form grid lines on the back surface of the IBC cell. Based on this, how to take advantage of laser-assisted sintering to improve the efficiency and performance of solar cells has become a problem to be solved in the field. CONTENT OF THE UTILITY MODEL

[0004] The present application provides a laser-assisted sintering pressurizing structure, which aims to improve the efficiency and performance of solar cells.

[0005] The present application provides a laser-assisted sintering pressurizing structure, which includes a power supply, a plurality of first contact electrodes and a plurality of second contact electrodes. The power supply includes a positive electrode and a negative electrode. The first contact electrode includes opposite first and second ends. The first ends of the plurality of first contact electrodes are electrically connected to the positive electrode of the power supply, and the second ends of the plurality of first contact electrodes are electrically connected to the positive electrode of the power supply. The plurality of first contact electrodes are used to apply a first voltage to the N-zone grid line paste. The second contact electrode includes opposite third and fourth ends. The third ends of the plurality of second contact electrodes are electrically connected to the negative electrode of the power supply, and the fourth ends of the plurality of second contact electrodes are electrically connected to the negative electrode of the power supply. The plurality of second contact electrodes are used to apply a second voltage to the P-zone grid line paste.

[0006] The pressurizing structure provided by the embodiments of the present application has a simple structure and low cost, and can be repeatedly used. In the process of laser-assisted sintering, the pressurizing structure can easily apply a bias voltage to the grid line paste. The process is simple and the cost is low. The advantages of laser-assisted sintering can be better utilized to improve the efficiency and performance of solar cells.

[0007] According to one embodiment of the present application, the pressurizing structure further includes a first connecting line and a second connecting line. The first connecting line is electrically connected to the first ends of the plurality of first contact electrodes, and the first connecting line is electrically connected to the positive electrode of the power supply. The second connecting line is electrically connected to the second ends of the plurality of first contact electrodes, and the second connecting line is electrically connected to the positive electrode of the power supply, so as to realize the parallel connection of the plurality of first contact electrodes and the positive electrode of the power supply.

[0008] According to one embodiment of the present application, the pressing structure further comprises a third connecting line and a fourth connecting line. The third connecting line is electrically connected to the third end of the plurality of second contact electrodes, and the third connecting line is electrically connected to the negative pole of the power supply. The fourth connecting line is electrically connected to the fourth end of the plurality of second contact electrodes, and the fourth connecting line is electrically connected to the negative pole of the power supply, so as to realize the parallel connection of the plurality of second contact electrodes and the negative pole of the power supply.

[0009] According to one embodiment of the present application, the plurality of first contact electrodes and the plurality of second contact electrodes are arranged on the same plane, so that the first contact electrodes can be in contact with the N-zone gate line paste, and the second contact electrodes can be in contact with the P-zone gate line paste at the same time.

[0010] According to one embodiment of the present application, the first contact electrodes and the second contact electrodes are alternately arranged in the first direction, so that the first contact electrodes can be in contact with the N-zone gate line paste, and the second contact electrodes can be in contact with the P-zone gate line paste.

[0011] According to one embodiment of the present application, the pressing structure further comprises a first fixing member and a second fixing member. The first fixing member is used to apply pressure to the first contact electrodes, so that the first contact electrodes can be in electrical contact with the N-zone gate line paste, and the automatic design of applying the bias voltage is facilitated. The second fixing member is used to apply pressure to the second contact electrodes, so that the second contact electrodes can be in electrical contact with the P-zone gate line paste, and the automatic design of applying the bias voltage is facilitated. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the present application, the following will briefly introduce the drawings needed to be used in some embodiments of the present application. Obviously, the drawings in the following description are only the drawings of some embodiments of the present application, and other drawings can also be obtained by those skilled in the art according to these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams, and are not the actual size of the product involved in the embodiments of the present application or the actual flow of the method.

[0013] Figure 1 The structural schematic diagram of the solar cell provided by the embodiments of the present application;

[0014] Figure 2 The schematic diagram of the pressing structure of the laser-assisted sintering provided by the embodiments of the present application;

[0015] Figure 3 The process schematic diagram of the laser-assisted sintering provided by the embodiments of the present application.

[0016] REFERENCE SIGNS:

[0017] 1. solar cell; 10, N zone gate line; 11, P zone gate line; 12, N zone gate line paste; 13, P zone gate line paste; 2, pressure structure; 20, first fixing member; 21, second fixing member; 3, power supply; 4, first contact electrode; 41, first end; 42, second end; 5, second contact electrode; 51, third end; 52, fourth end; 6, first connecting line; 7, second connecting line; 8, third connecting line; 9, fourth connecting line. DETAILED DESCRIPTION

[0018] The technical solutions in some embodiments of the present application will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments of the present application. Based on the embodiments provided in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0019] Unless otherwise required by context, the term "comprises" in the specification and claims is to be construed as open, inclusive, meaning "including but not limited to".

[0020] Hereinafter, the terms "first" and "second" are used only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first" and "second" can explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0021] In describing some embodiments, the term "connected" and its derivatives can be used. The term "connected" should be interpreted broadly, for example, "connected" can be fixedly connected, or detachably connected, or integrated; can be directly connected, or indirectly connected through an intermediate medium. For example, in describing some embodiments, the term "connected" can be used to indicate that two or more components have direct physical or electrical contact with each other.

[0022] In addition, the use of "based on" means open and inclusive, because the process, step, calculation or other action "based on" one or more stated conditions or values can be based on additional conditions or values beyond those stated in practice.

[0023] Exemplary embodiments are described herein with reference to cross-sectional illustrations that are idealized examples. In the drawings, the thickness of layers and regions are exaggerated for clarity. Accordingly, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and / or tolerances, are to be expected. Thus, the exemplary embodiments should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result from, for example, manufacturing. For example, an etched region illustrated as a rectangle will typically have rounded or curved features. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region of a device and are not intended to limit the scope of the exemplary embodiments.

[0024] Embodiments of the present application provide a solar cell, Figure 1 A structure diagram of the solar cell provided by embodiments of the present application is shown.

[0025] Referring to Figure 1 The solar cell 1 can be an Interdigitated Back Contact (IBC) cell, and the back surface of the IBC cell is provided with a plurality of N-zone grid lines 10 and a plurality of P-zone grid lines 11, which are arranged in a finger-shaped interdigitated manner along the direction X.

[0026] The solar cell 1 can also be a Tunneling Oxide Passivated Contact Back Contact (TBC) cell or a Heterojunction Back Contact (HBC) cell.

[0027] In the process of preparing the above-mentioned solar cell 1, the grid line paste is arranged on the N-zone and P-zone of the back surface of the solar cell 1, and the grid line paste is sintered by laser-assisted sintering to form the N-zone grid lines 10 and the plurality of P-zone grid lines 11.

[0028] Based on this, embodiments of the present application also provide a pressurizing structure for laser-assisted sintering of a solar cell, Figure 2 A structure diagram of the pressurizing structure for laser-assisted sintering provided by embodiments of the present application is shown.

[0029] Referring to Figure 2 The pressurizing structure for laser-assisted sintering 2 includes a power supply 3, a first contact electrode 4, and a second contact electrode 5.

[0030] The first contact electrode 4 comprises opposite first and second ends 41 and 42, the first ends 41 of the plurality of first contact electrodes 4 are electrically connected to the positive pole of the power supply 3, the second ends 42 of the plurality of first contact electrodes 4 are electrically connected to the positive pole of the power supply 3, and the plurality of first contact electrodes 4 are connected in parallel to form a loop. The first contact electrode 4 receives a first voltage from the positive pole of the power supply 3 and is used to apply the first voltage to the N-zone gate line paste.

[0031] The second contact electrode 5 comprises opposite third and fourth ends 51 and 52, the third ends 51 of the plurality of second contact electrodes 5 are electrically connected to the negative pole of the power supply 3, the fourth ends 52 of the plurality of second contact electrodes 5 are electrically connected to the negative pole of the power supply 3, and the plurality of second contact electrodes 5 are connected in parallel to form a loop. The second contact electrode 5 receives a second voltage from the negative pole of the power supply 3 and is used to apply the second voltage to the P-zone gate line paste, and the first voltage and the second voltage form a bias voltage.

[0032] The pressurizing structure 2 provided by the embodiment of the present application has simple structure and low cost, and can be repeatedly used. In the process of laser-assisted sintering, the bias voltage can be easily applied to the gate line paste through the pressurizing structure 2, the process is simple and the cost is low, the advantages of laser-assisted sintering can be better played, and the efficiency and performance of the solar cell 1 can be improved.

[0033] In some embodiments, referring to Figure 2 The pressurizing structure 2 further comprises a first connecting line 6 and a second connecting line 7, the first connecting line 6 is electrically connected to the first ends 41 of the plurality of first contact electrodes 4, and the first connecting line 6 is electrically connected to the positive pole of the power supply 3. The second connecting line 7 is electrically connected to the second ends 42 of the plurality of first contact electrodes 4, and the second connecting line 7 is electrically connected to the positive pole of the power supply 3, so as to realize the parallel connection of the plurality of first contact electrodes 4 and the positive pole of the power supply 3.

[0034] In some embodiments, referring to Figure 2 The pressurizing structure 2 further comprises a third connecting line 8 and a fourth connecting line 9, the third connecting line 8 is electrically connected to the third ends 51 of the plurality of second contact electrodes 5, and the third connecting line 8 is electrically connected to the negative pole of the power supply 3. The fourth connecting line 9 is electrically connected to the fourth ends 52 of the plurality of second contact electrodes 5, and the fourth connecting line 9 is electrically connected to the negative pole of the power supply 3, so as to realize the parallel connection of the plurality of second contact electrodes 5 and the negative pole of the power supply 3.

[0035] In some embodiments, referring to Figure 2 The plurality of first contact electrodes 4 and the plurality of second contact electrodes 5 are arranged on the same plane.

[0036] It can be understood that the N-area grid line paste and the P-area grid line paste on the back of the solar cell 1 are located in the same plane, and the first contact electrode 4 and the second contact electrode 5 are arranged in the same plane so that the first contact electrode 4 can contact the N-area grid line paste and the second contact electrode 5 can contact the P-area grid line paste at the same time.

[0037] In some embodiments, referring to Figure 2 , the first contact electrode 4 and the second contact electrode 5 are arranged alternately along the direction X.

[0038] It can be understood that the N-area grid line 10 and the P-area grid line 11 are arranged in a finger-shaped cross pattern on the back of the solar cell 1 along the direction X, that is, the N-area grid line paste and the P-area grid line paste are arranged in a finger-shaped cross pattern. Based on this, the first contact electrode 4 and the second contact electrode 5 are arranged alternately along the direction X so that the first contact electrode 4 can contact the N-area grid line paste and the second contact electrode 5 can contact the P-area grid line paste.

[0039] Figure 3 A process diagram of laser-assisted sintering is provided for the embodiments of the present application.

[0040] Referring to Figure 3 , in the process of laser-assisted sintering, the pressing structure 2 is placed on the back of the solar cell 1, and the spacing between the first contact electrode 4 and the second contact electrode 5 can be flexibly adjusted according to the designed spacing of the N-area grid line paste 12 and the P-area grid line paste 13. Then, the first contact electrode 4 is in pressure contact with the N-area grid line paste 12, and the second contact electrode 5 is in pressure contact with the P-area grid line paste 13. A first voltage is applied to the N-area grid line paste 12 through the first contact electrode 4, and a second voltage is applied to the P-area grid line paste through the second contact electrode 5. The bias voltage formed by the first voltage and the second voltage is continuously adjustable in the range of 1V-26V, which can be adjusted according to different conditions of the grid line paste and the laser, so as to achieve the best sintering effect.

[0041] At the same time, a large spot laser is used to irradiate the back of the solar cell 1. The laser uses infrared light with a wavelength of 1064nm or green light with a wavelength of 532nm, and the laser is a continuous laser with a power greater than 200W. A large spot is generated by defocusing and superimposed to cover the entire back of the solar cell 1. Under the irradiation of the laser, the photo-generated carriers generated by the solar cell 1 form a local current under the action of the bias voltage. The current is transmitted along the low-resistance path (grid line paste) to form a high-density current, so that the grid line paste generates heat, the passivation film on the back of the solar cell 1 is burned through, and the silver in the grid line paste and the silicon in the light-absorbing layer of the solar cell 1 diffuse and sinter with each other, thereby forming the N-area grid line 10 and the plurality of P-area grid lines 11.

[0042] Since the lifetime of photo-generated carriers is between microseconds and milliseconds, the current-induced heating time is also in this range, and then it cools down rapidly, the sintering formed silver-silicon alloy reduces the contact resistance of both, and the contact area of the gate line paste with the passivation film is small and the heating time of the gate line paste is short, which does not affect the passivation performance of the passivation film, and is conducive to improving the efficiency and performance of the solar cell 1 after laser-assisted sintering.

[0043] In some embodiments, referring to Figure 3 The pressing structure 2 further comprises a first fixing member 20 for applying pressure to the first contact electrode 4 to make the first contact electrode 4 in electrical contact with the N-zone gate line paste 12, which facilitates the automation design of applying the bias voltage.

[0044] Exemplarily, the first fixing member 20 can be a clip to clamp the first contact electrode 4 and the N-zone gate line paste 12 together to realize the electrical contact between the first contact electrode 4 and the N-zone gate line paste 12.

[0045] Referring to Figure 3 The pressing structure 2 further comprises a second fixing member 21 for applying pressure to the second contact electrode 5 to make the second contact electrode 5 in electrical contact with the P-zone gate line paste 13, which facilitates the automation design of applying the bias voltage.

[0046] Exemplarily, the second fixing member 21 can be a clip to clamp the second contact electrode 5 and the P-zone gate line paste 13 together to realize the electrical contact between the second contact electrode 5 and the P-zone gate line paste 13.

[0047] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can think of changes or replacements within the technical scope disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A pressurized structure for laser-assisted sintering, characterized by, The application relates to a pressing structure for a solar cell, comprising: a power supply including a positive pole and a negative pole; a plurality of first contact electrodes for applying a first voltage to N-zone gate line paste; the first contact electrodes include opposite first ends and second ends, the first ends of the plurality of first contact electrodes are electrically connected to the positive pole of the power supply, and the second ends of the plurality of first contact electrodes are electrically connected to the positive pole of the power supply; a plurality of second contact electrodes for applying a second voltage to P-zone gate line paste; the second contact electrodes include opposite third ends and fourth ends, the third ends of the plurality of second contact electrodes are electrically connected to the negative pole of the power supply, and the fourth ends of the plurality of second contact electrodes are electrically connected to the negative pole of the power supply.

2. The pressurized structure of claim 1, wherein The pressing structure further comprises a first connecting line and a second connecting line; the first connecting line is electrically connected to the first ends of the plurality of first contact electrodes, and the first connecting line is electrically connected to the positive pole of the power supply; the second connecting line is electrically connected to the second ends of the plurality of first contact electrodes, and the second connecting line is electrically connected to the positive pole of the power supply.

3. The pressurized structure of claim 1, wherein The pressing structure further comprises a third connecting line and a fourth connecting line; the third connecting line is electrically connected to the third ends of the plurality of second contact electrodes, and the third connecting line is electrically connected to the negative pole of the power supply; the fourth connecting line is electrically connected to the fourth ends of the plurality of second contact electrodes, and the fourth connecting line is electrically connected to the negative pole of the power supply.

4. The pressurized structure of claim 1, wherein The plurality of first contact electrodes and the plurality of second contact electrodes are arranged on the same plane.

5. The pressurized structure of claim 1, wherein In a first direction, the first contact electrodes and the second contact electrodes are alternately arranged.

6. The pressurized structure of claim 1, wherein The pressing structure further comprises a first fixing member and a second fixing member; the first fixing member is used for applying pressure to the first contact electrodes, so that the first contact electrodes are in electrical contact with the N-zone gate line paste; the second fixing member is used for applying pressure to the second contact electrodes, so that the second contact electrodes are in electrical contact with the P-zone gate line paste.

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