Electroplating circuit and electroplating method

Abstract

The invention discloses an electroplating circuit and an electroplating method, and the electroplating circuit comprises a power supply device, a first electroplating circuit and a second electroplating circuit. The first electroplating circuit comprises a first anode piece connected to a first anode output end of the power supply device and a first battery piece connecting piece connected to a first cathode output end of the power supply device, and the second electroplating circuit comprises a second anode piece connected to a second anode output end of the power supply device; the second battery piece connecting piece is connected to a second negative electrode output end of the power supply device; during electroplating, the first battery piece connecting piece is connected to the N surface of the battery piece, the second battery piece connecting piece is connected to the P surface of the battery piece, and the difference between the voltage drop of the second electroplating circuit and the voltage drop of the first electroplating circuit is smaller than or equal to a preset voltage value U0, so that a plating layer on the N surface and a plating layer on the P surface of the battery piece can reach corresponding preset thicknesses; and a basis is provided for adjusting the numerical values of the second voltage and the first voltage in the electroplating process.

Description

Technical Field

[0001] The present invention relates to the technical field of electroplating, and particularly relates to an electroplating circuit and an electroplating method. Background Art

[0002] When performing double-sided electroplating on the N side and the P side of a battery cell, in order to obtain different electroplating effects on the N side and the P side of the battery cell, generally, the method of controlling the electroplating duration is adopted to obtain different electroplating effects. For example, in order to make the coating thickness on the P side of the battery cell greater than that on the N side of the battery cell, the electroplating time on the P side of the battery cell can be increased. However, this will lead to an increase in the overall electroplating time of the battery cell and affect the electroplating efficiency of the battery cell. Summary of the Invention

[0003] The object of the present invention is to provide an electroplating circuit and an electroplating method, which can achieve different electroplating effects on both sides of a battery cell on the premise that the electroplating time on both sides of the battery cell is the same.

[0004] To achieve the above object, the technical solutions provided in the embodiments of the present invention are as follows.

[0005] In a first aspect, an embodiment of the present invention provides an electroplating circuit, including a power supply device, a first electroplating line, and a second electroplating line;

[0006] The first electroplating line includes a first anode member connected to the first positive output terminal of the power supply device, and a first battery cell connecting member connected to the first negative output terminal of the power supply device. The second electroplating line includes a second anode member connected to the second positive output terminal of the power supply device, and a second battery cell connecting member connected to the second negative output terminal of the power supply device;

[0007] During electroplating operation, the first battery cell connecting member is connected to the N side of the battery cell, the second battery cell connecting member is connected to the P side of the battery cell, and the difference between the voltage drop of the second electroplating line and the voltage drop of the first electroplating line is less than or equal to a preset voltage value U0.

[0008] In some embodiments, the power supply device is respectively connected to a first rectifier and a second rectifier. The positive electrode of the first rectifier is connected to the first anode member, the negative electrode of the first rectifier is connected to the first battery cell connecting member, the positive electrode of the second rectifier is connected to the second anode member, and the negative electrode of the second rectifier is connected to the second battery cell connecting member.

[0009] In some embodiments, the power supply device includes a first power supply and a second power supply. The first power supply is connected to the first rectifier, and the second power supply is connected to the second rectifier.

[0010] In some embodiments, the positive electrode of the first rectifier is connected to m first anode components in parallel, the negative electrode of the first rectifier is connected to m first cell connectors in parallel, the positive electrode of the second rectifier is connected to m second anode components in parallel, and the negative electrode of the second rectifier is connected to m second cell connectors in parallel.

[0011] In a second aspect, an embodiment of the present invention further provides an electroplating method, including the following steps:

[0012] Perform double-sided electroplating on the cell, and control the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell to be less than or equal to a preset voltage value.

[0013] In some embodiments, the electroplating method includes the following steps:

[0014] Obtain a preset voltage value U0,

[0015] Obtain the electroplating voltage U1 of the P side of the cell,

[0016] Obtain the electroplating voltage U2 of the N side of the cell,

[0017] If U2 - U1 ≤ U0, keep the values of U1 and U2 unchanged, and continue to electroplate the cell.

[0018] In some embodiments, the electroplating method includes the following steps: Synchronously obtain the electroplating voltage U1 of the P side of the cell and the electroplating voltage U2 of the N side of the cell at preset time intervals.

[0019] If U2 - U1 > U0, increase the value of U1 or decrease the value of U2 so that U2 - U1 ≤ U0.

[0020] In some embodiments, the electroplating method includes the following steps: If U2 - U1 > U0, continuously increase the value of U1 by a times the value of U1 each time until U2 - U1 ≤ U0, or continuously decrease the value of U2 by b times the value of U2 each time until U2 - U1 ≤ U0; where a > 1 and b < 1. Preferably, the range of a is 1.01 - 1.5, and the range of b is 0.5 - 0.99.

[0021] In some embodiments, the electroplating method includes the following steps: Electroplate the N sides of m cells using a first electroplating circuit, and electroplate the P sides of m cells using a second electroplating circuit;

[0022] Obtain the average preset voltage value U of the cell 0s ,

[0023] Obtain the total voltage U of the first electroplating circuit 1s ,

[0024] Obtain the total voltage U of the second electroplating circuit2s ,

[0025] If U 2s -U 1s > mU 0s , increase the value of U 1s or reduce the value of U 2s so that U 2s -U 1s ≤ U0.

[0026] In a third aspect, an embodiment of the present invention further provides an electroplating method, including the following steps:

[0027] Electroplate the N side of the battery cell using the first electroplating circuit, and electroplate the P side of the battery cell using the second electroplating circuit;

[0028] Obtain a preset voltage value U0,

[0029] Obtain the system resistance R1 in the electroplating state of the first electroplating circuit, and obtain the system resistance R2 in the electroplating state of the second electroplating circuit;

[0030] Obtain the current I1 in the electroplating state of the first electroplating circuit, and obtain the current I2 in the electroplating state of the second electroplating circuit;

[0031] If I2 × R2 - I1 × R1 > U0, increase the value of I1 or reduce the value of I2 so that I2 × R2 - I1 × R1 ≤ U0.

[0032] In some embodiments, the electroplating method includes the following steps: synchronously obtain the current I1 in the electroplating state of the first electroplating circuit and the current I2 in the electroplating state of the second electroplating circuit at preset time intervals;

[0033] If I2 × R2 - I1 × R1 ≤ U0, continue electroplating the battery cell.

[0034] Due to the application of the above technical solutions, compared with the prior art, the embodiments of the present invention have the following advantages: The electroplating circuit and electroplating method in this embodiment can achieve that the coatings on the N side and the P side of the battery cell reach the corresponding preset thickness; it also provides a basis for adjusting the numerical values of the second voltage and the first voltage during the electroplating process. When the numerical value of one of the voltages changes, according to the relationship between the second voltage and the first voltage, the numerical value of the other voltage can be quickly adjusted. Description of the Drawings

[0035] Att Figure 1 is the first structural schematic diagram of the electroplating circuit in the embodiment of the present invention;

[0036] Att Figure 2 is the second structural schematic diagram of the electroplating circuit in the embodiment of the present invention;

[0037] Appendix Figure 3 It is the third structural schematic diagram of the electroplating circuit in the embodiment of the present invention;

[0038] Appendix Figure 4 It is the fourth structural schematic diagram of the electroplating circuit in the embodiment of the present invention;

[0039] Appendix Figure 5 It is the fifth structural schematic diagram of the electroplating circuit in the embodiment of the present invention;

[0040] Among them, the meanings of the reference numerals are as follows:

[0041] Solar cell 1, first solar cell connecting member 101, second solar cell connecting member 102; first anode member 11, second anode member 12, power supply 20, first power supply 21, second power supply 22, rectifier 30, first rectifier 31, second rectifier 32, first anode member main circuit wire 411, first connection rod 412, first anode member branch circuit wire 413, first adjustable resistor 414, first cathode main circuit wire 415, second anode member main circuit wire 421, second connection rod 422, second anode member branch circuit wire 423, second adjustable resistor 424, second cathode main circuit wire 425, counter 50, PLC 60. Detailed implementation manners

[0042] The following elaborates on the preferred embodiments of the present invention in conjunction with the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art. It should be noted here that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation to the present invention.

[0043] Such as Figure 1 Or Figure 3As shown in the figure, this embodiment provides an electroplating circuit, including a power supply device, a first electroplating circuit, and a second electroplating circuit. The first electroplating circuit includes a first anode member 11 connected to the first positive output terminal of the power supply device, and a first cell connecting member 101 connected to the first negative output terminal of the power supply device. The second electroplating circuit includes a second anode member 12 connected to the second positive output terminal of the power supply device, and a second cell connecting member 102 connected to the second negative output terminal of the power supply device. During electroplating, the first cell connecting member 101 is connected to the N surface of cell 1, and the second cell connecting member 102 is connected to the P surface of cell 2. The difference between the voltage drop of the second electroplating circuit and the voltage drop of the first electroplating circuit is less than or equal to the preset voltage value U0 of cell 1. Alternatively, define the voltage applied to the N surface of cell 1 as the first voltage, and the voltage applied to the P surface of cell 1 as the second voltage. The difference between the second voltage and the first voltage is less than or equal to the preset voltage value U0 of cell 1. Through this electroplating circuit, the coatings on the N surface and the P surface of cell 1 can reach the corresponding preset thickness; it also provides a basis for adjusting the values of the second voltage and the first voltage during the electroplating process. When the value of one of the voltages changes, according to the relationship between the second voltage and the first voltage, the value of the other voltage can be quickly adjusted. During the electroplating process, the cell is in a moving state, and at different time periods, different regions on the cell will be electroplated correspondingly. If the difference between the second voltage and the first voltage is kept less than or equal to the preset voltage value U0 of cell 1, the electroplating uniformity between different regions on one side of the cell can be improved, that is, the intra-cell uniformity of the cell can be improved.

[0044] During electroplating, part of the first electroplating circuit is immersed in the electroplating solution, and part of the second electroplating circuit is also immersed in the electroplating solution. The electroplating solution will connect and conduct the two sides of cell 1, making the first electroplating circuit and the second electroplating circuit connected. In addition, the first electroplating circuit is connected to the N surface of cell 1, and the second electroplating circuit is connected to the P surface of cell 1. Cell 1 itself will also be conducted, making the first electroplating circuit and the second electroplating circuit connected again. If the connection situation between the first electroplating circuit and the second electroplating circuit is not considered, only based on the difference in electroplating requirements on the two sides of cell 1, the theoretical voltage acting on the two sides of cell 1 can be calculated. Then, actually, the first electroplating circuit and the second electroplating circuit will be connected, and the connected area between the two will share the voltage, resulting in the actual voltage acting on the two sides of cell 1 being different from the theoretical voltage and unable to meet the electroplating requirements on the two sides of cell 1. Therefore, it is necessary to compensate for the voltage drop of the second electroplating circuit and the voltage drop of the first electroplating circuit, and the compensation value is the preset voltage value U0. The preset voltage value U0 depends on the difference in electroplating requirements on the two sides of cell 1 and the voltage sharing situation in the connected area between the first electroplating circuit and the second electroplating circuit. For example, the preset voltage value U0 is equal to the theoretical voltage difference U between the two sides of cell 1. 01and the open-circuit voltage U OL The sum, i.e., U0 = U 01 + U OL , can reduce the influence of the open-circuit voltage U OL on the plating uniformity of the battery cells.

[0045] Furthermore, as electroplating progresses, the value of the theoretical voltage difference U 01 increases, causing the value of U0 to also increase. Therefore, it is necessary to appropriately reduce the value of U0.

[0046] In some embodiments, the power supply device can be a multi-output DC power supply. Preferably, the magnitude of the DC current output by each output terminal is variable to facilitate adjusting the voltage in the first plating circuit and / or the second plating circuit according to process requirements. The power supply device can also be two DC power supplies, one for the first plating circuit and the other for the second plating circuit. Preferably, the magnitude of the output current of the DC power supply is variable to facilitate adjusting the voltage in the first plating circuit and / or the second plating circuit according to process requirements. As Figure 2 , the power supply device can also include a power supply 20 and a rectifier 30. The power supply 20 outputs an alternating current, which is rectified by the rectifier 30 to output a direct current. Both the power supply 20 and the rectifier 30 can be one or more. When there is one, the output terminal of the rectifier 30 should be multiple and capable of outputting different currents.

[0047] Specifically, the power supply device is respectively connected to a first rectifier 31 and a second rectifier 32. The positive pole of the first rectifier 31 is connected to the first anode member 11, the negative pole of the first rectifier 31 is connected to the first battery cell connection member 101, the positive pole of the second rectifier 32 is connected to the second anode member 12, and the negative pole of the second rectifier 32 is connected to the second battery cell connection member 102.

[0048] Specifically, as Figure 4 or Figure 5 shown, the power supply device includes a first power supply 21 and a second power supply 22. The first power supply 21 is connected to the first rectifier 31, and the second power supply 22 is connected to the second rectifier 32. The positive pole of the first rectifier 31 is connected to the first anode member 11, the negative pole of the first rectifier 31 is connected to the first battery cell connection member 101, the positive pole of the second rectifier 32 is connected to the second anode member 12, and the negative pole of the second rectifier 32 is connected to the second battery cell connection member 102.

[0049] In some embodiments, the positive electrode of the first rectifier 31 is connected to m first anode members 11 in parallel, and the negative electrode of the first rectifier 31 is connected to m first cell connecting members 101 in parallel. The m first anode members 11 and the m first cell connecting members 101 are arranged in one-to-one correspondence. The positive electrode of the second rectifier 32 is connected to m second anode members 12 in parallel, and the negative electrode of the second rectifier 32 is connected to m second cell connecting members 102 in parallel. The m second anode members 12 and the m second cell connecting members 102 are arranged in one-to-one correspondence. During electroplating, the m first cell connecting members 101 are connected to the N surfaces of the m cells 1 in one-to-one correspondence, and the N surfaces of the m cells 1 are arranged opposite to the m first anode members 11 in one-to-one correspondence; the m second cell connecting members 102 are connected to the P surfaces of the m cells 1 in one-to-one correspondence, and the P surfaces of the m cells 1 are arranged opposite to the m second anode members 12 in one-to-one correspondence. Then, the preset voltage value U0 is equal to the theoretical voltage difference mU of both sides of the m cells 1 01 and the open-circuit voltage mU OL sum, that is, U0 = mU 01 + mU OL . Wherein, m is a positive integer.

[0050] In some embodiments, the m first anode members 11 are all horizontally arranged and spaced along a preset direction to form a first anode member group; the m second anode members 12 are all horizontally arranged and spaced along a preset direction to form a second anode member group; the second anode member group is arranged directly below the first anode member group, and a cell channel is formed between the second anode member group and the first anode member group. The cells 1 will be electroplated when passing through the cell channel. The number of cells 1 entering the cell channel is n, and it is impossible to ensure that all areas on the n cells 1 are electroplated synchronously. The effective electroplating area is equivalent to the area of αn cells 1, and the preset voltage value U0 = αnU 01 + αnU OL . Wherein, n and m are positive integers, and n may not be equal to m, 0 < α < 1.

[0051] Specifically, as Figure 2 or Figure 4 shown, the electroplating circuit includes two groups of anode members arranged opposite to each other up and down. One group of anode members located above includes a plurality of first anode members 11 spaced along the cell conveying direction, and one group of anode members located below includes a plurality of second anode members 12 spaced along the cell conveying direction. The first anode members 11 and the second anode members 12 are arranged opposite to each other. Preferably, each first anode member 11 is arranged opposite to a second anode member 12.

[0052] As Figure 2As shown, the power supply 20 is connected to the rectifier 30. The first positive output terminal of the rectifier 30 is connected to the first anode main circuit wire 411. The first anode main circuit wire 411 is connected to the first connection rod 412. The first connection rod 412 is connected to the first anode 11 through the first anode branch wire 413. Each first anode branch wire 413 is connected to one first anode 11. In order to ensure that the line resistance between the first connection rod 412 and each first anode 11 is consistent, a first adjustable resistor 414 is provided on each first anode branch wire 413 to adjust the line resistance between the first connection rod 412 and each first anode 11 to make it consistent.

[0053] The second positive output terminal of the rectifier 30 is connected to the second anode main circuit wire 421. The second anode main circuit wire 421 is connected to the second connection rod 422. The second connection rod 422 is connected to the second anode 12 through the second anode branch wire 423. Each second anode branch wire 423 is connected to one second anode 12. In order to ensure that the line resistance between the second connection rod 422 and each second anode 12 is consistent, a second adjustable resistor 424 is provided on each second anode branch wire 423 to adjust the line resistance between the second connection rod 422 and each second anode 12 to make it consistent.

[0054] A cell plating channel is formed between two sets of anodes arranged vertically. The cell 1 is conveyed to the plating channel for plating. When entering the plating channel, the counter 50, such as a photoelectric counter, counts the cells 1 entering the plating channel. The first negative output terminal of the rectifier 30 is connected to the first cathode main circuit wire 415. The first cathode main circuit wire 415 is connected to a plurality of parallel first cathode branch wires. Each first cathode branch wire is connected to the N side of a cell 1. The second negative output terminal of the rectifier 30 is connected to the second cathode main circuit wire 425. The second cathode main circuit wire 425 is connected to a plurality of parallel second cathode branch wires. Each second cathode branch wire is connected to the P side of a cell 1. The power supply 20, the rectifier 30, and the counter 50 are communicatively connected to the PLC 60. The PLC 60 controls the output current of the power supply 20 and / or the rectifier according to the counting result of the counter 50. For example, if there are 5 cells in the plating channel, the output current of the first positive output terminal of the rectifier is 5I; if there are 8 cells in the plating channel, the output current of the first positive output terminal of the rectifier is 8I.

[0055] Figure 4 The structure shown and Figure 2Basically the same, except that: the power supply device includes a first power supply 21 and a second power supply 22. The first power supply 21 is connected to a first rectifier 31. The positive output terminal of the first rectifier 31 is connected to the first anode main circuit wire 411, and the negative output terminal of the first rectifier 31 is connected to the first cathode main circuit wire 415. The second power supply 22 is connected to a second rectifier 32. The positive output terminal of the second rectifier 32 is connected to the second anode main circuit wire 421, and the negative output terminal of the second rectifier 32 is connected to the second cathode main circuit wire 425.

[0056] In some embodiments, as Figure 5 shown, the m first anode members 11 are all vertically arranged and spaced apart along a preset direction to form a first anode member group; the m second anode members 12 are all vertically arranged and spaced apart along a preset direction to form a second anode member group; the m first anode members 11 and the m second anode members 12 are arranged in an interleaved manner, and an electroplating interval is formed between adjacent first anode member 11 and second anode member 12. After the battery wafer 1 is placed in the electroplating interval, it can be electroplated. Then, the preset voltage value U0 is equal to the theoretical voltage difference mU of both sides of the m battery wafers 1 01 and the open circuit voltage mU OL sum, that is, U0 = mU 01 + mU OL . Wherein, m is a positive integer.

[0057] On the other hand, the embodiments of the present application further provide an electroplating method, including the following steps:

[0058] Perform double-sided electroplating on the battery wafer, and control the difference between the electroplating voltage of the P side of the battery wafer and the electroplating voltage of the N side of the battery wafer to be less than or equal to the preset voltage value U0. The electroplating voltage of the N side of the battery wafer can be understood as the first voltage, and the electroplating voltage of the P side of the battery wafer can be understood as the second voltage. By this method, it is possible to achieve that the coatings on the N side and the P side of the battery wafer 1 reach the corresponding preset thickness; it also provides a basis for adjusting the numerical values of the second voltage and the first voltage during the electroplating process. When the numerical value of one of the voltages changes, according to the relationship between the second voltage and the first voltage, the numerical value of the other voltage can be quickly adjusted. During the electroplating process, the battery wafer is in a moving state, and at different time periods, different regions on the battery wafer will be electroplated correspondingly. If the difference between the second voltage and the first voltage is kept less than or equal to the preset voltage value U0 of the battery wafer 1, the electroplating uniformity between different regions on one side of the battery wafer can be improved, that is, the intra-wafer uniformity of the battery wafer can be improved.

[0059] During electroplating, part of the first electroplating circuit is immersed in the electroplating solution, and part of the second electroplating circuit is also immersed in the electroplating solution. The electroplating solution will connect and conduct both sides of the cell 1, causing the first electroplating circuit and the second electroplating circuit to be connected. In addition, the first electroplating circuit is connected to the N side of the cell 1, and the second electroplating circuit is connected to the P side of the cell 1. The cell 1 itself will also be conducted, causing the first electroplating circuit and the second electroplating circuit to be connected again. If the connection between the first electroplating circuit and the second electroplating circuit is not considered, and only based on the difference in electroplating requirements on both sides of the cell 1, the theoretical voltage acting on both sides of the cell 1 can be calculated. However, in fact, the first electroplating circuit and the second electroplating circuit will be connected, and the connected area will divide the voltage, resulting in the actual voltage acting on both sides of the cell 1 being different from the theoretical voltage and unable to meet the electroplating requirements on both sides of the cell 1. Therefore, it is necessary to compensate for the voltage drop of the second electroplating circuit and the voltage drop of the first electroplating circuit, and the compensation value is the preset voltage value U0. The preset voltage value depends on the difference in electroplating requirements on both sides of the cell 1 and the voltage division situation in the connected area between the first electroplating circuit and the second electroplating circuit. For example, the preset voltage value U0 is equal to the theoretical voltage difference U 01 and the open-circuit voltage U OL sum, that is, U0 = U 01 + U OL , which can reduce the influence of the open-circuit voltage U OL on the electroplating uniformity of the cell.

[0060] In some embodiments, the electroplating method includes: obtaining the preset voltage value U0, obtaining the electroplating voltage U1 of the P side of the cell, obtaining the electroplating voltage U2 of the N side of the cell, and if U2 - U1 ≤ U0, keeping the values of U1 and U2 unchanged and continuing to electroplate the cell.

[0061] In some embodiments, the electroplating method includes: synchronously obtaining the electroplating voltage U1 of the P side of the cell and the electroplating voltage U2 of the N side of the cell at every preset time interval. If U2 - U1 > U0, increasing the value of U1 or reducing the value of U2 so that U2 - U1 ≤ U0.

[0062] In some embodiments, the electroplating method includes: if U2 - U1 > U0, the value of U1 is continuously increased by a times the value of U1 each time until U2 - U1 ≤ U0, or the value of U2 is continuously decreased by b times the value of U2 each time until U2 - U1 ≤ U0; where a > 1 and b < 1. The range of a is preferably 1.01 - 1.5, and the range of b is preferably 0.5 - 0.99. For example, the Uoc of the HJT double-sided cell is about 0.75V. Control the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell to be less than or equal to 0.75V. When the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell is greater than 0.75V, the electroplating voltage of the N side of the cell is continuously increased by 1.1 times the electroplating voltage of the N side of the cell each time until the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell is less than or equal to 0.75V.

[0063] In some embodiments, the electroplating method includes: electroplating the N sides of m cells using a first electroplating circuit, and electroplating the P sides of m cells using a second electroplating circuit; obtaining the average preset voltage value U of the cells 0s , obtaining the total voltage U of the first electroplating circuit 1s , obtaining the total voltage U of the second electroplating circuit 2s , if U 2s - U 1s > mU 0s , increase the value of U 1s or reduce the value of U 2s such that U 2s - U 1s ≤ U0. For example, electroplating the N sides of 10 HJT cells using a first electroplating circuit, and electroplating the P sides of 10 HJT cells using a second electroplating circuit. The Uoc of a single HJT double-sided cell is about 0.75V. Control the difference between the electroplating voltage of the P sides of 10 HJT cells and the electroplating voltage of the N sides of 10 HJT cells to be less than or equal to 7.5V. When the difference between the electroplating voltage of the P sides of the cells and the electroplating voltage of the N sides of the cells is greater than 7.5V, the electroplating voltage of the N sides of the cells is continuously increased by 1.1 times the electroplating voltage of the N sides of the cells each time until the difference between the electroplating voltage of the P sides of the cells and the electroplating voltage of the N sides of the cells is less than or equal to 7.5V.

[0064] On the other hand, an embodiment of the present application also provides an electroplating method, including the following steps:

[0065] The N side of the cell is electroplated using the first electroplating circuit, and the P side of the cell is electroplated using the second electroplating circuit; a preset voltage value U0 is obtained, the system resistance R1 in the electroplating state of the first electroplating circuit is obtained, and the system resistance R2 in the electroplating state of the second electroplating circuit is obtained; the current I1 in the electroplating state of the first electroplating circuit is obtained, and the current I2 in the electroplating state of the second electroplating circuit is obtained; if I2×R2 - I1×R1 > U0, increase the value of I1 or decrease the value of I2 so that I2×R2 - I1×R1 ≤ U0. For example, the N side of the HJT cell is electroplated using the first electroplating circuit, and the P side of the HJT cell is electroplated using the second electroplating circuit. The Uoc of the HJT double-sided cell is about 0.75V. Control the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell to be less than or equal to 0.75V. When the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell is greater than 0.75V, continuously increase the current of the first electroplating circuit by 1.1 times the current of the first electroplating circuit each time, or continuously decrease the current of the second electroplating circuit by 0.9 times the current of the second electroplating circuit each time until the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell is less than or equal to 0.75V. The result of I1×R1 can be understood as the first voltage, and the result of I2×R2 can be understood as the second voltage. Through this method, the coatings on the N side and the P side of the cell 1 can reach the corresponding preset thickness; it also provides a basis for adjusting the numerical values of the second voltage and the first voltage during the electroplating process. When the numerical value of one of the voltages changes, according to the relationship between the second voltage and the first voltage, the numerical value of the other voltage can be quickly adjusted. During the electroplating process, the cell is in a moving state. At different time periods, different areas on the cell will be electroplated correspondingly. If the difference between the second voltage and the first voltage is kept less than or equal to the preset voltage value U0 of the cell 1, the electroplating uniformity between different areas on one side of the cell can be improved, that is, the in-cell uniformity of the cell can be improved.

[0066] In some embodiments, the current I1 in the electroplating state of the first electroplating circuit and the current I2 in the electroplating state of the second electroplating circuit are synchronously obtained at preset time intervals; if I2×R2 - I1×R1 ≤ U0, continue to electroplate the cell. The current I1 in the electroplating state of the first electroplating circuit and the current I2 in the electroplating state of the second electroplating circuit are monitored in real time to keep the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell within a suitable process parameter range and maintain the electroplating uniformity.

[0067] The above embodiments are only for illustrating the technical concept and characteristics of the present invention, and their purpose is to enable those familiar with this technology to understand the content of the present invention and implement it. It should not be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. An electroplating circuit, characterized in that, It includes a power supply device, a first electroplating circuit and a second electroplating circuit; The first electroplating circuit includes a first anode connected to the first positive output terminal of the power supply device, and a first cell connector connected to the first negative output terminal of the power supply device. The second electroplating circuit includes a second anode connected to the second positive output terminal of the power supply device, and a second cell connector connected to the second negative output terminal of the power supply device; During electroplating operation, the first cell connector is connected to the N side of the cell, the second cell connector is connected to the P side of the cell, and the difference between the voltage drop of the second electroplating circuit and the voltage drop of the first electroplating circuit is less than or equal to a preset voltage value U0.

2. The electroplating circuit according to claim 1, wherein: The power supply device is respectively connected to a first rectifier and a second rectifier. The positive pole of the first rectifier is connected to the first anode, the negative pole of the first rectifier is connected to the first cell connector, the positive pole of the second rectifier is connected to the second anode, and the negative pole of the second rectifier is connected to the second cell connector.

3. The electroplating circuit according to claim 2, wherein: The power supply device includes a first power supply and a second power supply. The first power supply is connected to the first rectifier, and the second power supply is connected to the second rectifier.

4. The electroplating circuit according to claim 2, characterized in that: The positive pole of the first rectifier is connected to m parallel-connected first anodes, the negative pole of the first rectifier is connected to m parallel-connected first cell connectors, the positive pole of the second rectifier is connected to m parallel-connected second anodes, and the negative pole of the second rectifier is connected to m parallel-connected second cell connectors.

5. An electroplating method, characterized in that, It includes the following steps: Perform double-sided electroplating on the cell, and control the difference between the electroplating voltage of the P side of the cell and the electroplating voltage of the N side of the cell to be less than or equal to a preset voltage value.

6. The electroplating method according to claim 5, wherein: Obtain the preset voltage value U0, Obtain the electroplating voltage U1 of the P side of the cell, Obtain the electroplating voltage U2 of the N side of the cell, If U2 - U1 ≤ U0, keep the values of U1 and U2 unchanged, and continue to electroplate the cell.

7. The electroplating method according to claim 6, wherein: Synchronously obtain the electroplating voltage U1 of the P side of the cell and the electroplating voltage U2 of the N side of the cell at every preset time interval, If U2 - U1 > U0, increase the value of U1 or decrease the value of U2 so that U2 - U1 ≤ U0.

8. The electroplating method according to claim 6, wherein: If U2 - U1 > U0, continuously increase the value of U1 by a times the value of U1 each time until U2 - U1 ≤ U0, or continuously decrease the value of U2 by b times the value of U2 each time until U2 - U1 ≤ U0; wherein, a > 1, b < 1.

9. The electroplating method according to claim 8, wherein: The range of a is 1.01 - 1.5, and the range of b is 0.5 - 0.

99.

10. The electroplating method according to claim 5, wherein: Use the first electroplating circuit to electroplate the N sides of m cells, and use the second electroplating circuit to electroplate the P sides of m cells; Obtain the average preset voltage value U of the battery cell 0s , Obtain the total voltage U of the first electroplating circuit 1s , Obtain the total voltage U of the second electroplating circuit 2s , If U 2s -U 1s >mU 0s , increase the value of U 1s or decrease the value of U 2s such that U 2s -U 1s ≤U0.

11. An electroplating method, characterized in that, It includes the following steps: Use the first electroplating circuit to electroplate the N side of the cell, and use the second electroplating circuit to electroplate the P side of the cell; Obtain the preset voltage value U0, Obtain the system resistance R1 in the electroplating state of the first electroplating circuit, and obtain the system resistance R2 in the electroplating state of the second electroplating circuit; Obtain the current I1 in the electroplating state of the first electroplating circuit, and obtain the current I2 in the electroplating state of the second electroplating circuit; If I2×R2 - I1×R1 > U0, increase the value of I1 or decrease the value of I2 so that I2×R2 - I1×R1 ≤ U0.

12. The electroplating circuit according to claim 11, wherein: Synchronously obtain the current I1 in the electroplating state of the first electroplating circuit and the current I2 in the electroplating state of the second electroplating circuit every preset time interval; if I2×R2 - I1×R1 ≤ U0, continue to electroplate the battery cell.

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