Welding wire bonding glue for photovoltaic 0BB assembly as well as preparation method and application of welding wire bonding glue

Abstract

The invention relates to the technical field of solar photovoltaics, in particular to welding wire bonding glue for a photovoltaic 0BB assembly and a preparation method and application of the welding wire bonding glue. The welding wire bonding glue for the photovoltaic 0BB assembly comprises the following components in parts by weight, comprising the following components in parts by weight: 20 to 50 parts of vinyl silicone resin, 20 to 50 parts of vinyl silicone oil, 10 to 20 parts of octavinyl dimethyl siloxy polyhedral oligomeric silsesquioxane, 1 to 10 parts of heptaisobutyl trisilanol polyhedral oligomeric silsesquioxane, 0.5 to 3 parts of methacryloyloxypropyl cyclotetrasiloxane, 0.5 to 3 parts of acryloyloxypropyl polyhedral oligomeric silsesquioxane and 5 to 20 parts of a thixotropic agent. 1-10 parts of hydrogen-containing silicone oil and 0.05-2 parts of an anti-poisoning microcapsule catalyst. The welding wire bonding glue for the photovoltaic 0BB assembly prepared by the invention has good adhesion to low-temperature welding wires, yellowing resistance, low volatile components at high temperature and good high and low temperature impact performance.

Description

Technical Field

[0001] The present invention relates to the field of solar photovoltaic technology, and in particular to a welding wire adhesive for photovoltaic 0BB components and a preparation method and application thereof. Background Art

[0002] Traditional PERC, new TOPcon cells and HJT (heterojunction) cells, especially HJT cells, require a high amount of silver paste. Under the premise of energy saving and cost reduction, reducing the use of silver paste has become one of the important ways to reduce costs.

[0003] Busbar-free modules, also known as 0BB technology, are an innovative photovoltaic cell module technology that eliminates the busbar of traditional cells and uses welding strips to derive current in the module link. Specifically, busbar-free cells use welding strips to collect fine grid current and interconnect cells. The width of the welding strip is smaller than the width of the traditional busbar. In addition, busbar-free cells usually use copper welding strips, and the original silver electrode busbar is completely replaced, realizing the function of base metal replacing the traditional silver busbar. The benefits of 0BB are: 1) reduce silver consumption; 2) enhance conductivity; 3) low-temperature packaging process can carry thinner silicon wafers.

[0004] At present, the main bonding materials for 0BB solder strips are UV glue, heat-curing epoxy glue, and heat-curing organic silicone glue. Among them, light-curing materials have been widely studied and rapidly promoted in various industries due to their many outstanding advantages such as fast curing speed, environmental friendliness, low energy consumption, and no solvent volatilization. However, UV light-curing glue also has its own limitations. Conventional UV light-curing glue has obvious limitations in the application scenarios of yellowing resistance and small molecule migration, and UV curing has certain damage to the battery cell; epoxy glue has high adhesion to welding wire, but epoxy glue has disadvantages such as high brittleness and yellowing; organic silicone system has natural aging resistance, but organic silicone has low bonding strength to welding strips. In 0BB packaging applications, the welding wire used is tin-plated copper low-temperature welding wire. In order to make the welding wire and the gate line have good adhesion during the lamination process, flux is usually added, but this flux will affect the curing and bonding strength of the glue. Summary of the invention

[0005] In view of the above deficiencies in the prior art, the object of the present invention is to provide a welding wire adhesive for photovoltaic 0BB components and a preparation method and application thereof.

[0006] To achieve the above objectives, the technical solutions adopted are:

[0007] One of the purposes of the present invention is to provide a welding wire adhesive for photovoltaic 0BB components, which comprises the following components in parts by weight: 20-50 parts of vinyl silicone resin, 20-50 parts of vinyl silicone oil, 10-20 parts of octavinyldimethylsiloxy cage polysilsesquioxane, 1-10 parts of heptaisobutyltrisilanol cage polysilsesquioxane, 0.5-3 parts of methacryloyloxypropyl cyclotetrasiloxane, 0.5-3 parts of acryloxypropyl cage polysilsesquioxane, 5-20 parts of thixotropic agent, 1-10 parts of hydrogen-containing silicone oil, and 0.05-2 parts of anti-poisoning microcapsule catalyst.

[0008] Preferably, the vinyl silicone resin is an MQ silicone resin containing vinyl groups, with a vinyl mass content of 1%-2% and a viscosity of 4000-8000 mPa.s.

[0009] Preferably, the vinyl silicone oil is a vinyl double-seal silicone oil with a viscosity of 5000-10000 mPa.s and a vinyl mass content of 0.15%-0.17%.

[0010] More preferably, the viscosity of the vinyl silicone oil is 5000-6000 mPa.s.

[0011] Preferably, the octavinyldimethylsiloxy cage-like polysilsesquioxane ( POSS106) is an organic and inorganic hybrid cage-like polysilsesquioxane with a molecular size of 1.5 nm and a structure of:

[0012]

[0014] Preferably, the heptaisobutyltrisilanol cage-like polysilsesquioxane ( POSS201) is an organic and inorganic hybrid cage-like polysilsesquioxane with a molecular size of 1.5 nm and a structure of:

[0015]

[0016] Preferably, the methacryloxypropyl cyclotetrasiloxane ( CTS102) is an organic and inorganic hybrid cyclotetrasiloxane with a viscosity of 100-300mPa.s and a structure of:

[0017]

[0018] Preferably, the acryloxypropyl cage-type polysilsesquioxane ( POSS1013) is a cage-like polysilsesquioxane with a nanoscale molecular size and a viscosity of 1800-2200 mPa.s. The structure is:

[0019]

[0020] Preferably, the hydrogen-containing silicone oil is a silicone oil with H-terminated and pendant H functional bonds, with a hydrogen content of 5.0-10.0 mmoles / g, and its structure is as follows:

[0021]

[0022] Among them, M=1~10, D=1~10.

[0023] Preferably, the anti-poisoning microcapsule catalyst is a microcapsule type platinum catalyst;

[0024] Preferably, the thixotropic agent is hydrophobic fumed silica or hydrophilic fumed silica. The hydrophilic fumed silica is at least one of Wacker's T40, Evonik's A300, and A380; the hydrophobic fumed silica is at least one of Wacker's H30, Evonik's R202, R972, and R974, etc., and the hydrophobic fumed silica is more preferred.

[0025] The second object of the present invention is to provide a method for preparing a welding wire adhesive for photovoltaic 0BB components, comprising the following steps: adding 20-50 parts of vinyl silicone resin, 20-50 parts of vinyl silicone oil, 10-20 parts of octavinyldimethylsiloxy cage polysilsesquioxane, 1-10 parts of heptaisobutyltrisilanol cage polysilsesquioxane, 0.5-3 parts of methacryloxypropyl cyclotetrasiloxane, and 0.5-3 parts of acryloxypropyl cage polysilsesquioxane to a reaction container and stirring, setting the temperature to 80°C, stirring for 3 hours, and then naturally cooling to room temperature, adding 5-20 parts of thixotropic agent, continuing to stir at room temperature for 1 hour, adding 1-10 parts of hydrogenated silicone oil and 0.05-2 parts of anti-poisoning microcapsule catalyst, and stirring at room temperature for 1 hour to obtain welding wire adhesive for photovoltaic 0BB components.

[0026] The third purpose of the present invention is to provide an application of the welding wire adhesive for photovoltaic 0BB components in the field of photovoltaic 0BB components.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: the welding wire adhesive for photovoltaic 0BB modules described in the present invention. The silicone resin used mainly provides the strength of the silicon system, and the vinyl content is controlled at 1%-2%. If the viscosity is too low, it will be brittle, and if the viscosity is too high, there will be problems with the processability, so it is most appropriate to control the viscosity of the vinyl silicone oil to 5000-6000mpa.s; the introduction of octavinyldimethylsiloxy cage polysilsesquioxane is mainly to improve the wear resistance and hardness of the product, followed by the introduction of the cage polysilsesquioxane structure, and its structure has good adhesion to the welding wire; the introduction of heptaisobutyltrisilanol cage polysilsesquioxane is mainly because it contains hydroxyl groups in its structure, which is very helpful for the viscosity stability of the addition type silica gel , and secondly, it will also be of great help to the bonding of the welding wire; the introduction of methacryloxypropyl cyclotetrasiloxane and acryloxypropyl cage polysilsesquioxane is mainly to improve the adhesion to the welding wire. The structure of cage polysilsesquioxane has good wettability with metal, especially after adding flux, its strength attenuation is low; the addition of thixotropic agent is to ensure a certain glue height after printing, and also to ensure its transparency and printing process characteristics; the introduction of anti-poisoning catalyst is mainly to ensure its curing speed and stability. The flux on the surface of the welding wire will affect the platinum catalyst, but the anti-poisoning catalyst will not be affected by this. DETAILED DESCRIPTION

[0028] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0029] Example 1

[0030] Add 30 parts of vinyl silicone resin with a viscosity of 6000 mPa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000 mPa.s and a vinyl content of 0.15%, 10 parts of octavinyldimethylsiloxy cage polysilsesquioxane, 5 parts of heptaisobutyltrisilanol cage polysilsesquioxane, 2 parts of methacryloxypropyl cyclotetrasiloxane, and 2 parts of acryloxypropyl cage polysilsesquioxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, then cool naturally to room temperature, add 10 parts of H30 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0 mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0031] Example 2

[0032] Add 40 parts of vinyl silicone resin with a viscosity of 7000 mPa.s and a vinyl content of 1.2%, 30 parts of vinyl silicone oil with a viscosity of 6000 mPa.s and a vinyl content of 0.15%, 15 parts of octavinyldimethylsiloxy caged polysilsesquioxane, 5 parts of heptaisobutyltrisilanol caged polysilsesquioxane, 2 parts of methacryloxypropyl cyclotetrasiloxane, and 2 parts of acryloxypropyl caged polysilsesquioxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, then cool naturally to room temperature, add 10 parts of H30 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0 mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0033] Example 3

[0034] Add 30 parts of vinyl silicone resin with a viscosity of 6000 mPa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000 mPa.s and a vinyl content of 0.15%, 15 parts of octavinyldimethylsiloxy cage polysilsesquioxane, 8 parts of heptaisobutyltrisilanol cage polysilsesquioxane, 2 parts of methacryloxypropyl cyclotetrasiloxane, and 2 parts of acryloxypropyl cage polysilsesquioxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, then cool naturally to room temperature, add 10 parts of H30 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0 mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0035] Comparative Example 1

[0036] Add 30 parts of vinyl silicone resin with a viscosity of 6000mpa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000mpa.s and a vinyl content of 0.15%, 10 parts of ordinary model DY-VMQ102 vinyl dimethyl silicone resin, 5 parts of heptaisobutyltrisilanol cage-like polysilsesquioxane, 2 parts of methacryloxypropyl cyclotetrasiloxane, and 2 parts of acryloxypropyl cage-type polysilsesquioxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, then cool naturally to room temperature, add 10 parts of H30 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0037] Comparative Example 2

[0038] Add 30 parts of vinyl silicone resin with a viscosity of 6000mPa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000mPa.s and a vinyl content of 0.15%, 10 parts of octavinyldimethylsiloxy caged polysilsesquioxane, 5 parts of heptaisobutyltrisilanol caged polysilsesquioxane, and 4 parts of commercially available KH-570 siloxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, then cool naturally to room temperature, add 10 parts of H30 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0039] Comparative Example 3

[0040] Add 30 parts of vinyl silicone resin with a viscosity of 6000mPa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000mPa.s and a vinyl content of 0.15%, 15 parts of octavinyldimethylsiloxy cage-like polysilsesquioxane, and 4 parts of commercially available KH-570 siloxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, and then naturally cool to room temperature. After adding 10 parts of H30 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0041] Comparative Example 4

[0042] Add 30 parts of vinyl silicone resin with a viscosity of 6000 mPa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000 mPa.s and a vinyl content of 0.15%, 10 parts of octavinyldimethylsiloxy caged polysilsesquioxane, 5 parts of heptaisobutyltrisilanol caged polysilsesquioxane, 2 parts of methacryloxypropyl cyclotetrasiloxane, and 2 parts of acryloxypropyl caged polysilsesquioxane into a reactor and stir. Set the temperature to 80°C, stir for 3 hours, and then cool naturally to room temperature. After adding 10 parts of Evonik R972 thixotropic agent, continue stirring at room temperature for 1 hour, add 5 parts of 6.0 mmoles / g hydrogen-containing silicone oil and 1 part of Jiangmen Kejunchi PT-2500D anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which is sealed and stored.

[0043] Comparative Example 5

[0044] 30 parts of vinyl silicone resin with a viscosity of 6000 mPa.s and a vinyl content of 1.2%, 40 parts of vinyl silicone oil with a viscosity of 7000 mPa.s and a vinyl content of 0.15%, 10 parts of octavinyldimethylsiloxy cage polysilsesquioxane, 5 parts of heptaisobutyltrisilanol cage polysilsesquioxane, 2 parts of methacryloxypropyl cyclotetrasiloxane, and 2 parts of acryloxypropyl cage polysilsesquioxane were added to a reactor and stirred. The temperature was set to 80°C and stirred for 3 hours, then naturally cooled to room temperature, 10 parts of H30 thixotropic agent were added, and stirring was continued at room temperature for 1 hour. 5 parts of 6.0 mmoles / g hydrogen-containing silicone oil, 1 part of Heraeus Pt=5000 ppm catalyst, and 0.5 parts of acetylene alcohol inhibitor were added, and stirred at room temperature for 1 hour to obtain 0BB component welding wire bonding glue, which was sealed and stored.

[0045] The performance of the encapsulation adhesive for photovoltaic 0BB technology of the present invention was tested by the following experiment, and the results are shown in Table 1.

[0046] Table 1. Performance index table of examples and comparative examples

[0047]

[0048]

[0049] From the above results, it can be seen that the welding wire adhesive for photovoltaic 0BB components of the present invention has good adhesion to the welding tape. In comparative examples 1 and 3, when octavinyldimethylsiloxy cage polysilsesquioxane or heptaisobutyltrisilanol cage polysilsesquioxane is not added, the bonding strength becomes lower, and the strength is even lower after adding flux; secondly, the addition of heptaisobutyltrisilanol cage polysilsesquioxane has a good effect on viscosity stability; at the same time, comparative examples 2 and 3 choose to add other silane coupling agents, and their transparency will also decrease. In comparative example 4, different thixotropic agents are mainly selected, which have a great difference in transparency; in comparison with comparative example 5, it is found that the use of anti-poisoning capsule structure catalyst is mainly the use of the side effect of flux on the catalyst, which significantly improves the side effect of flux on the catalyst and meets the bonding performance of the welding tape for photovoltaic component 0BB technology.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A welding wire adhesive for photovoltaic 0BB components, characterized in that: The invention comprises the following components in parts by weight: 20-50 parts of vinyl silicone resin, 20-50 parts of vinyl silicone oil, 10-20 parts of octavinyldimethylsiloxy cage-like polysilsesquioxane, 1-10 parts of heptaisobutyltrisilanol cage-like polysilsesquioxane, 0.5-3 parts of methacryloxypropyl cyclotetrasiloxane, 0.5-3 parts of acryloxypropyl cage-type polysilsesquioxane, 5-20 parts of thixotropic agent, 1-10 parts of hydrogen-containing silicone oil and 0.05-2 parts of anti-poisoning microcapsule catalyst.

2. According to claim 1, the welding wire adhesive for photovoltaic OBB components is characterized in that: The vinyl silicone resin is an MQ silicone resin containing vinyl groups, with a vinyl mass content of 1%-2% and a viscosity of 4000-8000 mpa.s.

3. According to claim 1, the welding wire adhesive for photovoltaic OBB components is characterized in that: The vinyl silicone oil is a vinyl double-seal silicone oil with a viscosity of 5000-10000 mpa.s and a vinyl mass content of 0.15%-0.17%.

4. According to claim 3, the welding wire adhesive for photovoltaic OBB components is characterized in that: The viscosity of the vinyl silicone oil is 5000-6000mpa.s.

5. According to claim 1, the welding wire adhesive for photovoltaic OBB components is characterized in that: The structure of the octavinyldimethylsiloxy cage-like polysilsesquioxane is:

6. The welding wire adhesive for photovoltaic OBB components according to claim 1, characterized in that: The heptaisobutyltrisilanol cage-like polysilsesquioxane structure is:

7. The welding wire adhesive for photovoltaic OBB components according to claim 1, characterized in that: The methacryloyloxypropyl cyclotetrasiloxane has a viscosity of 100-300 mPa.s and a structure of:

8. According to claim 1, the welding wire adhesive for photovoltaic OBB components is characterized in that: The structure of the acryloxypropyl cage-type polysilsesquioxane is: The hydrogen-containing silicone oil is silicone oil with H end-capping and pendant H functional bonds, and the hydrogen content is 5.0-10.0 mmoles / g; the anti-poisoning microcapsule catalyst is a microcapsule type platinum catalyst; the thixotropic agent is hydrophobic fumed silica powder or hydrophilic fumed silica.

9. A method for preparing a welding wire adhesive for photovoltaic 0BB modules as claimed in claims 1 to 8, characterized in that: The following steps are involved: Add 20-50 parts of vinyl silicone resin, 20-50 parts of vinyl silicone oil, 10-20 parts of octavinyldimethylsiloxy cage polysilsesquioxane, 1-10 parts of heptaisobutyltrisilanol cage polysilsesquioxane, 0.5-3 parts of methacryloxypropyl cyclotetrasiloxane, and 0.5-3 parts of acryloxypropyl cage polysilsesquioxane into a reaction container and stir. Set the temperature to 80°C, stir for 3 hours, then cool naturally to room temperature, add 5-20 parts of thixotropic agent, continue stirring at room temperature for 1 hour, add 1-10 parts of hydrogen-containing silicone oil and 0.05-2 parts of anti-poisoning microcapsule catalyst, and stir at room temperature for 1 hour to obtain welding wire bonding glue for photovoltaic 0BB components.

10. An application of the welding wire adhesive for photovoltaic 0BB components as described in any one of claims 1 to 8 in the field of photovoltaic 0BB components.

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