Photovoltaic conductive method and preparation of electroplating reduction pretreatment agent

Abstract

The invention provides a photovoltaic conductive method and a preparation method of an electroplating reduction pretreatment agent, and the method comprises the following steps: for a photovoltaic substrate, electroplating the surface of a photovoltaic material by using the high potential of the same family or adjacent family of metal zinc, gallium, tin, indium, copper and the like so as to carry out conductive treatment, and covering the surface of the photovoltaic substrate with an electroplating reducing agent; putting the treated photovoltaic substrate into a copper sulfate electroplating solution, and electroplating to metallize the surface of a photovoltaic material, so that the photovoltaic material has conductivity; compared with traditional photovoltaic production, the method is more convenient, safer and lower in cost, the whole electroplating process (electroplating reduction pretreatment-copper electroplating) can be completed on one line, more equipment cost is saved, PVD and metal palladium are replaced with the electroplating reduction pretreatment agent, and cost output is greatly reduced from raw materials.

Description

Technical Field

[0001] The invention belongs to the technical field of circuit board electroplating, and specifically relates to a photovoltaic conductive method and the preparation of an electroplating reduction pretreatment agent. Background Art

[0002] Energy is the most basic driving force for the development and economic growth of the entire world and the foundation for human survival.

[0003] Solar energy is an inexhaustible energy source. If we can obtain electricity from solar energy, it will benefit mankind. People use the photovoltaic effect to manufacture solar cells for photoelectric conversion. It is completely different from other power generation principles in the past. It has the following characteristics: ① No danger of exhaustion; ② Absolutely clean (pollution-free); ③ Not limited by the geographical distribution of resources; ④ Can generate electricity near the electricity consumption point; ⑤ High energy quality; ⑥ Users are emotionally easy to accept; ⑦ It takes a short time to obtain energy. The disadvantages are: ① The energy distribution density of the irradiation is small, that is, it takes up a huge area; ② The energy obtained is related to meteorological conditions such as the four seasons, day and night, and cloudy and sunny weather. But in general, the disadvantages do not outweigh the advantages. As a new energy source, solar energy has great advantages, so it is favored by countries around the world.

[0004] In the past, silver paste was mainly used as a conductive metal and was an important consumable required for the production of photovoltaic cells.

[0005] It is composed of silver powder, glass powder, organic matter and additives. After a series of quality inspections, it is transported to the battery manufacturer. Through screen printing technology, a silver electrode grid structure is formed on the thin surface of the battery cell to collect and conduct current on the surface of the battery cell. Its performance is related to the photoelectric performance of photovoltaic cells. Therefore, it is the core material in the production process of photovoltaic cells. Its cost is very high, with a cost of 0.07 yuan per watt, accounting for 33% of the non-silicon cost of the battery cell. It accounts for 8%-10% of the overall cost of the battery cell. Among the raw materials of photovoltaic silver paste, silver powder, as a precious metal, plays a decisive role, accounting for 98% of the cost structure of photovoltaic silver paste raw materials;

[0006] As a non-renewable energy, the cost and utilization rate of raw materials are often difficult to reach the required level.

[0007] In summary, the present invention provides a method for photovoltaic conductivity and preparation of an electroplating reduction pretreatment agent to solve the above problems. Summary of the invention

[0008] In order to solve the above technical problems, the present invention provides a photovoltaic conductivity method and the preparation of an electroplating reduction pretreatment agent to solve the problems in the prior art that the cost and the utilization rate of raw materials are often difficult to reach the required level.

[0009] A method for photovoltaic conductivity, comprising:

[0010] For photovoltaic substrates, the high potential of metals such as zinc, gallium, tin, indium, copper, etc., which are in the same group or adjacent group, is used to electroplate the surface of the photovoltaic material for conductivity, wherein the electroplating reducing agent covers the surface of the photovoltaic substrate;

[0011] The treated photovoltaic substrate is then placed in a copper sulfate electroplating solution to metallize the surface of the photovoltaic material, thereby making it conductive.

[0012] Furthermore, the surface of the photovoltaic substrate includes an oxide layer material such as ITO / CTO / TTO.

[0013] Furthermore, using a metal of the same group or adjacent group as the main salt, one of metal zinc, gallium, tin, indium, and nickel as the raw material, and matching with a corresponding chelating agent, reducing agent, and wetting agent, the bonding strength and conductivity of the photovoltaic panel substrate are improved.

[0014] A method for preparing an electroplating reduction pretreatment agent, comprising a main salt, a conductive salt, a reducing agent, a chelating agent, a wetting agent and a defoaming agent, the balance being water;

[0015] The following steps are also included:

[0016] Step 1: Weigh the specified weight portions of the main salt and the chelating agent, dissolve them in part of the water, and stir them evenly to obtain a mixture A, and place it at 50° for more than two hours;

[0017] Step 2: Add the reducing agent to mixture A and let it stand for about 30 minutes, then add the remaining water from other ingredients and stir to mix.

[0018] Further, the raw materials include:

[0019] Main salt: The main salt is a metal of the same group or adjacent group, such as zinc, gallium, tin, indium, nickel, copper, etc., and its main compounds including zinc sulfate, gallium sulfate, indium sulfate, nickel sulfate hexahydrate, stannous sulfate, copper sulfate pentahydrate, etc.;

[0020] Conductive salts: phosphates;

[0021] Reducing agent: at least two substances selected from catechol, sodium hypophosphite, resorcinol, hydroquinone, glyoxylic acid, hydrazine hydrate, sodium borohydride, ascorbic acid, borane, acrolein, etc.;

[0022] Chelating agents: at least two of the following: phosphates, aminocarboxylic acids, 1,3-diketones, hydroxycarboxylic acids, pyrophosphates, polyamines, citric acid, sodium ethylenediaminetetraacetate, etc.;

[0023] Wetting agent: at least two substances selected from triethylhexyl phosphate, sodium lauryl sulfate, methyl amyl alcohol, cellulose derivatives, polyacrylamide, guar gum, fatty acid polyethylene glycol esters, alkylphenol polyoxyethylene ether, nonylphenol polyoxyethylene ether, etc.;

[0024] Defoaming agent: at least one of special modified polyether, phosphate, etc.

[0025] Further, the following raw materials in parts by weight are also included:

[0026] Main salt: 10-100 parts;

[0027] Conductive salt: 1-5 parts;

[0028] Chelating agent: 15-80 parts;

[0029] Reducing agent: 15-50 parts;

[0030] Wetting agent: 2-10 parts;

[0031] Defoaming agent: 0.1-2 parts;

[0032] The balance is water.

[0033] Furthermore, the water is deionized water.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The present invention utilizes the photovoltaic substrate to oxidize the metal material. The high potential of the same or adjacent group makes the surface of the photovoltaic material conductively enhanced by electrochemical reduction plating, so that it has strong conductivity. The same or adjacent group metal is used as the main salt, and metal zinc, gallium, tin, indium, nickel and other raw materials are used. The corresponding chelating agent, reducing agent, wetting agent, etc. can improve the substrate bonding strength and conductivity of the oxide layer material such as ITO / CTO / TTO of the photovoltaic panel, and can effectively improve the mutual bonding strength with the copper layer.

[0036] 2. Compared with traditional photovoltaic production, the present invention is more convenient, safer and has lower cost. It can complete the entire electroplating process (electroplating reduction pretreatment - electroplating copper) on one line, saving more equipment costs. The electroplating reduction pretreatment agent replaces PVD and metal palladium, which greatly reduces the cost output from the raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0038] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0039] like Figure 1 As shown, the present invention provides a method for photovoltaic conductivity, comprising:

[0040] For photovoltaic substrates, the high potential of metals such as zinc, gallium, tin, indium, copper, etc., which are in the same group or adjacent group, is used to electroplate the surface of the photovoltaic material for conductivity, wherein the electroplating reducing agent covers the surface of the photovoltaic substrate;

[0041] The treated photovoltaic substrate is then placed in a copper sulfate electroplating solution to metallize the surface of the photovoltaic material, thereby making it conductive.

[0042] As an embodiment of the present invention, the surface of the photovoltaic substrate includes an oxide layer material such as ITO / CTO / TTO.

[0043] As an embodiment of the present invention, a metal of the same group or adjacent group is used as the main salt, and one of the metals zinc, gallium, tin, indium, and nickel is used as the raw material, in combination with corresponding chelating agents, reducing agents, and wetting agents to improve the bonding strength and conductivity of the photovoltaic panel substrate.

[0044] A method for preparing an electroplating reduction pretreatment agent, comprising a main salt, a conductive salt, a reducing agent, a chelating agent, a wetting agent and a defoaming agent, the balance being water;

[0045] The following steps are also included:

[0046] Step 1: Weigh the specified weight portions of the main salt and the chelating agent, dissolve them in part of the water, and stir them evenly to obtain a mixture A, and place it at 50° for more than two hours;

[0047] Step 2: Add the reducing agent to mixture A and let it stand for about 30 minutes, then add the remaining water from other ingredients and stir to mix.

[0048] As an embodiment of the present invention, the raw materials include:

[0049] Main salt: The main salt is a metal of the same group or adjacent group, such as zinc, gallium, tin, indium, nickel, copper, etc., and its main compounds including zinc sulfate, gallium sulfate, indium sulfate, nickel sulfate hexahydrate, stannous sulfate, copper sulfate pentahydrate, etc.;

[0050] Conductive salts: phosphates;

[0051] Reducing agent: at least two substances selected from catechol, sodium hypophosphite, resorcinol, hydroquinone, glyoxylic acid, hydrazine hydrate, sodium borohydride, ascorbic acid, borane, acrolein, etc.;

[0052] Chelating agents: at least two of the following: phosphates, aminocarboxylic acids, 1,3-diketones, hydroxycarboxylic acids, pyrophosphates, polyamines, citric acid, sodium ethylenediaminetetraacetate, etc.;

[0053] Wetting agent: at least two substances selected from triethylhexyl phosphate, sodium lauryl sulfate, methyl amyl alcohol, cellulose derivatives, polyacrylamide, guar gum, fatty acid polyethylene glycol esters, alkylphenol polyoxyethylene ether, nonylphenol polyoxyethylene ether, etc.;

[0054] Defoaming agent: at least one of special modified polyether, phosphate, etc.

[0055] As an embodiment of the present invention, the following raw materials in parts by weight are also included:

[0056] Main salt: 10-100 parts;

[0057] Conductive salt: 1-5 parts;

[0058] Chelating agent: 15-80 parts;

[0059] Reducing agent: 15-50 parts;

[0060] Wetting agent: 2-10 parts;

[0061] Defoaming agent: 0.1-2 parts;

[0062] The balance is water.

[0063] As an embodiment of the present invention, deionized water is used.

[0064] Different types of photovoltaic substrates are subjected to conductive pretreatment (Sn-Cu, I N-Cu, NI-Cu, etc.) by different processes. The electroplating reducing agent is used on the surface of the photovoltaic material to accelerate the conductive treatment of the substrate surface through current and non-current state, forming a layer of dense small crystal tin, zinc, nickel, indium, copper and other metal elements, and then the treated photovoltaic substrate is placed in a copper sulfate electroplating solution for electroplating. Electrolysis is used to form a uniform, dense, and well-bonded metal on the surface of the photovoltaic material. The current process of not using PVD magnetron is solved, the cost is reduced, and the bonding force of the copper surface circuit is also well guaranteed.

[0065] The present invention utilizes the oxidized metal material of the photovoltaic substrate. The high potential of the same group or neighboring group makes the surface of the photovoltaic material conductively enhanced through electrochemical reduction plating, so that it has strong conductivity. The same group or neighboring group metal is used as the main salt, and metal zinc, gallium, tin, indium, nickel and other raw materials are used. The corresponding chelating agent, reducing agent, wetting agent and the like can improve the substrate bonding strength and conductivity of the oxide layer materials such as ITO / CTO / TTO of the photovoltaic panel, and can effectively improve the mutual bonding strength with the copper layer. Compared with traditional photovoltaic production, it is more convenient, safer and has lower cost. It can realize one line to complete the entire electroplating process (electroplating reduction pretreatment-electroplating copper), saving more equipment costs. The electroplating reduction pretreatment agent replaces PVD and metal palladium, which greatly reduces the cost output from the raw materials.

[0066] Embodiment 1:

[0067] A method for preparing an electroplating reduction pretreatment agent comprises the following raw materials:

[0068] Main salts: stannous sulfate, nickel sulfate hexahydrate, gallium sulfate, indium sulfate, copper sulfate pentahydrate

[0069] Conductive salt: phosphate

[0070] Chelating agents: phosphates, 1,3-diketone, etc.

[0071] Reducing agent: catechol, glyoxylic acid, ascorbic acid, borane, etc.

[0072] Wetting agent: sodium dodecyl sulfate, alkylphenol polyoxyethylene ether, etc.

[0073] Defoamer: Polyether defoamer

[0074] The balance is water;

[0075] Among them, the following raw materials are included in weight:

[0076] Main salt: 10-100 parts;

[0077] Conductive salt: 1-5 parts;

[0078] Chelating agent: 20-80 parts;

[0079] Reducing agent: 15-20 parts;

[0080] Wetting agent: 2-10 parts;

[0081] Defoaming agent: 0.1-2 parts;

[0082] Water: Remaining.

[0083] Wherein, deionized water is used.

[0084] The following steps are also included:

[0085] Step 1: Weigh the specified weight portions of the main salt and the chelating agent, dissolve them in part of the water, and stir them evenly to obtain a mixture A, and place it at 50° for more than two hours;

[0086] Step 2: Add the reducing agent to mixture A and let it stand for about 30 minutes, then add the remaining water from other ingredients and stir to mix.

[0087] Embodiment 2:

[0088] Main salts: stannous sulfate, nickel sulfate hexahydrate, gallium sulfate, indium sulfate, copper sulfate pentahydrate

[0089] Conductive salt: phosphate

[0090] Chelating agents: phosphates, pyrophosphates, sodium EDTA, etc.

[0091] Reducing agent: resorcinol, ascorbic acid, borane, hydrazine hydrate, etc.

[0092] Wetting agent: sodium dodecyl sulfate, alkylphenol polyoxyethylene ether, etc.

[0093] Defoamer: Polyether defoamer

[0094] The balance is water.

[0095] Among them, the following raw materials are included in weight:

[0096] Main salt: 10-100 parts;

[0097] Conductive salt: 1-5 parts;

[0098] Chelating agent: 15-50 parts;

[0099] Reducing agent: 30-50 parts;

[0100] Wetting agent: 2-10 parts;

[0101] Defoaming agent: 0.1-2 parts;

[0102] Water: Remaining.

[0103] Wherein, deionized water is used.

[0104] The following steps are also included:

[0105] Step 1: Weigh the specified weight portions of the main salt and the chelating agent, dissolve them in part of the water, and stir them evenly to obtain a mixture A, and place it at 50° for more than two hours;

[0106] Step 2: Add the reducing agent to mixture A and let it stand for about 30 minutes, then add the remaining water from other ingredients and stir to mix.

[0107] In order to replace the traditional silver paste conductivity and the later PVD as conductive copper, copper is used instead of silver to increase the bonding strength.

[0108] In order to reduce costs and processes, electroplating reduction pretreatment agents are proposed. Their purpose is to replace PVD and other processes and to increase their bonding strength.

[0109] In the past, the process of replacing silver paste with electroless nickel plating after PVD, other palladium, silver and other catalyst metals, now uses electrochemical reduction of metals to form a uniform, dense and well-bonded metal on the surface of photovoltaic materials. It plays a key role in the conductivity and bonding strength of the back-end electroplated copper.

[0110] The photovoltaic substrate is used to oxidize the metal material. The high potential of the same or adjacent group makes the surface of the photovoltaic material more conductive through electrochemical reduction plating, thus making it have strong conductivity.

[0111] In the past, the process of replacing silver paste with electroless nickel plating after PVD, other palladium, silver and other catalyst metals, now uses electrochemical reduction of metals to form a uniform, dense and well-bonded metal on the surface of photovoltaic materials. It plays a key role in the conductivity and bonding strength of the back-end electroplated copper.

[0112] In the present invention, the anode and cathode are placed in a chemical plating tank and are continuously energized. The current causes negatively charged ions (anions) to move to the anode and positively charged ions (cations) to move to the cathode, thereby covering or plating a uniform metal coating on the surface of the target component. In the process of the energized cations moving to the cathode, the greater the current, the faster the movement speed, and vice versa. Since the photovoltaic substrate itself has poor conductivity, the requirements for current are relatively reduced. At this time, it is necessary to rely on the reduction effect of the solution itself for treatment. It is called a plating reduction pretreatment agent.

[0113] The electroplating reduction pretreatment agent can form a metal thin shell on the surface of the base material (usually an oxidized metal material), and then copper sulfate is electroplated on the surface. It can replace pretreatment processes such as PVD and palladium activation.

[0114] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for photovoltaic conductivity, characterized in that: include: For photovoltaic substrates, the high potential of metals such as zinc, gallium, tin, indium, copper, etc., which are in the same group or adjacent group, is used to electroplate the surface of the photovoltaic material for conductivity, wherein the electroplating reducing agent covers the surface of the photovoltaic substrate; The treated photovoltaic substrate is then placed in a copper sulfate electroplating solution to metallize the surface of the photovoltaic material, thereby making it conductive.

2. The photovoltaic conductive method according to claim 1, characterized in that: The surface of the photovoltaic substrate includes an oxide layer material such as ITO / CTO / TTO.

3. The photovoltaic conductive method according to claim 1, characterized in that: The main salt is a metal of the same group or adjacent group, and one of the metals zinc, gallium, tin, indium, and nickel is used as the raw material, in combination with the corresponding chelating agent, reducing agent, and wetting agent to improve the bonding strength and conductivity of the photovoltaic panel substrate.

4. A method for preparing an electroplating reduction pretreatment agent, applied to the photovoltaic conductivity method as claimed in claims 1-3, characterized in that: It includes main salt, conductive salt, reducing agent, chelating agent, wetting agent and defoaming agent, and the balance is water; The following steps are also included: Step 1: Weigh the specified weight portions of the main salt and the chelating agent, dissolve them in part of the water, and stir them evenly to obtain a mixture A, and place it at 50° for more than two hours; Step 2: Add the reducing agent to mixture A and let it stand for about 30 minutes, then add the remaining water from other ingredients and stir to mix.

5. The method for preparing the electroplating reduction pretreatment agent according to claim 4, characterized in that: The raw materials include: Main salt: The main salt is a metal of the same group or adjacent group, such as zinc, gallium, tin, indium, nickel, copper, etc., and its main compounds including zinc sulfate, gallium sulfate, indium sulfate, nickel sulfate hexahydrate, stannous sulfate, copper sulfate pentahydrate, etc.; Conductive salts: phosphates; Reducing agent: at least two substances selected from catechol, sodium hypophosphite, resorcinol, hydroquinone, glyoxylic acid, hydrazine hydrate, sodium borohydride, ascorbic acid, borane, acrolein, etc.; Chelating agents: at least two of the following: phosphates, aminocarboxylic acids, 1,3-diketones, hydroxycarboxylic acids, pyrophosphates, polyamines, citric acid, sodium ethylenediaminetetraacetate, etc.; Wetting agent: at least two substances selected from triethylhexyl phosphate, sodium lauryl sulfate, methyl amyl alcohol, cellulose derivatives, polyacrylamide, guar gum, fatty acid polyethylene glycol esters, alkylphenol polyoxyethylene ether, nonylphenol polyoxyethylene ether, etc.; Defoaming agent: at least one of special modified polyether, phosphate, etc.

6. The method for preparing the electroplating reduction pretreatment agent according to claim 4, characterized in that: The following raw materials in parts by weight are also included: Main salt: 10-100 parts; Conductive salt: 1-5 parts; Chelating agent: 15-80 parts; Reducing agent: 15-50 parts; Wetting agent: 2-10 parts; Defoaming agent: 0.1-2 parts; The balance is water.

7. The method for preparing the electroplating reduction pretreatment agent according to claim 4, characterized in that: The water used is deionized water.

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