CN-115621365-B - Photovoltaic device preparation process

Abstract

The invention provides a preparation process of a photovoltaic device, which comprises the following steps of S1, adopting a pure copper sheet with the thickness of 0.25mm, welding and attaching the copper sheet and an aluminum radiator through a welding process, S2, welding and attaching a bypass diode and a terminal seat to a circuit substrate in an SMT mode through a middle height Wen Xigao, S3, fixing a chip with silver paste, conducting wire bonding and packaging, and then conducting 175 ℃ two-hour curing on the chip and the circuit substrate, S4, uniformly scraping and coating the chip on the copper sheet of the aluminum radiator through a stainless steel solder paste net by using 138 ℃ low-temperature solder paste, preheating the copper sheet through a reflow soldering furnace, S5, fixing a battery module on the copper sheet on the aluminum radiator which is pre-coated with the low-temperature solder paste, and conducting overheating for 10 minutes through the reflow soldering furnace. The invention solves the problems that the heat conduction is blocked and the power generation efficiency is affected due to the fact that the hole heat concentration is easily formed by combining the traditional battery module and the radiator through the heat conduction silica gel, and has simple process and low cost.

Inventors

• Zhao kunshan
• YANG JINXIANG

Assignees

• 大庆华研环保应用技术研发中心有限公司

Dates

Publication Date

20260512

Application Date

20221104

Claims (6)

1. 1. The preparation process of the photovoltaic device comprises a battery module and an aluminum radiator, wherein the battery module comprises a bypass diode, a terminal seat, a battery assembly and a circuit substrate; the method is characterized by comprising the following steps of: S1, adopting a pure copper sheet with the thickness of 0.25mm, and welding and attaching the copper sheet and an aluminum radiator through a welding process at 450 ℃, wherein the radiator is required to be insulated to different degrees according to the size of the radiator during welding, and the heat insulation temperature is required to be controlled at 380 ℃ for a 200g radiator as an example; S2, welding and bonding the bypass diode and the terminal seat with the circuit substrate in an SMT mode through a medium height Wen Xigao at 245 ℃; s3, carrying out die bonding and wire bonding packaging on the chip by silver paste to form a battery assembly, and then curing the chip and the circuit substrate for two hours at 175 ℃ to form a battery module; s4, uniformly scraping the low-temperature tin paste at 138 ℃ on a copper sheet welded on an aluminum radiator in advance through a stainless steel tin paste net, and passing through an eight-section furnace of a reflow furnace, wherein the highest temperature of the reflow furnace is 150 ℃; S5, preheating a reflow soldering furnace; And S6, fixing the battery module on the copper sheet on the aluminum radiator which is coated with the low-temperature solder paste in advance by using a clamp, and overheating the copper sheet for 10 minutes by using a reflow soldering furnace to achieve the low-temperature soldering effect, wherein the surface temperature of a bonding pad of the circuit substrate is controlled at 138 ℃, and once the low-temperature solder paste reaches the melting point, the heat source is required to be removed immediately and the temperature is reduced.
2. 2. The process of claim 1, wherein the circuit substrate is a copper circuit substrate.
3. 3. The process of claim 1, wherein the circuit substrate is provided with bonding pads, the bonding pads comprise a negative bonding pad and a positive bonding pad, and the battery assembly is connected with the negative bonding pad and the positive bonding pad.
4. 4. The process for manufacturing a photovoltaic device according to claim 1, wherein the battery assembly comprises a battery chip, a packaging line and a packaging body shell, the packaging line is connected to two ends of the battery chip, the battery chip is arranged in the packaging body shell, and the packaging body shell is connected with the upper surface of the circuit substrate.
5. 5. The process of claim 1, wherein the number of the terminal blocks is 2, and the terminal blocks are disposed on a diagonal line of the circuit substrate.
6. 6. The process according to claim 1, wherein the silver paste in step S3 has a silver content of 85%.

Description

Photovoltaic device preparation process Technical Field The invention relates to the technical field of photovoltaic modules, in particular to a preparation process of a photovoltaic device. Background Photovoltaic power generation is a technology that uses the photovoltaic effect of a semiconductor interface to directly convert light energy into electrical energy. The photovoltaic cell has the advantages of being free from influence of building orientation, long in illumination receiving time, capable of avoiding shadow interference to the greatest extent and the like. In the prior art, a packaging mode of a photovoltaic battery module adopts COB (Chip On Board), and is limited by packaging production equipment and welding temperature limitation when parts are welded in the production process, a module circuit substrate, a bypass diode and a terminal seat can be adopted, firstly, a middle-high Wen Xigao is adopted to carry out welding lamination in an SMT mode, then, after a photovoltaic chip is subjected to die bonding and wire bonding packaging by silver paste (85% of silver content), the photovoltaic chip is solidified for two hours at 175 ℃, in order to avoid that the silver paste at the lamination position of the battery chip is melted due to heating caused by overhigh melting point of soldering tin, and thus, the chip and gold wires are loosened to generate displacement and functional structural damage, the whole process is limited by the working size and the battery size of the packaging equipment in the market, and the production efficiency and the rejection rate of the photovoltaic battery are low. The traditional concentrating photovoltaic gallium arsenide battery module is combined with a radiator in a heat-conducting silica gel way, but heat conduction is blocked due to hole heat concentration which is easy to form, for example, in the Chinese patent publication number CN 207083051U, the publication date 2018.03.09, a low-concentration photovoltaic cell panel radiator fixing device is disclosed, and comprises a glass plate and a silicon battery, the front surface of the silicon battery is fixedly provided with the glass plate, the back surface of the silicon battery is provided with a heat-conducting silica gel pad, the heat-conducting silica gel pad is adhered with the radiator, the outer side surface of the radiator is provided with a left-right corresponding support connecting piece, the outer side surface of the support connecting piece is welded with a bolt hole, the upper side surface and the lower side surface of the support connecting piece are uniformly distributed with corresponding U-shaped connecting pieces, the bottom surface of the U-shaped connecting pieces is tightly attached to the upper side and the lower side surface of the radiator, a fixing screw is arranged at the corresponding position, the upper end surface of the U-shaped connecting pieces is fixedly connected with the upper side and the lower side of the glass plate through clamping grooves, the other end surface of the U-shaped connecting pieces is tightly pressed on the outer side surface of the radiator through fastening bolts. The concentrating photovoltaic gallium arsenide battery module is combined with the radiator, the ideal condition is that the intermediate thermal resistance is minimum, and the solution is welding. The heat conduction efficiency of copper is best to replace by an aluminum radiator in view of cost, the welding joint of copper-aluminum alloy is at an excessive temperature of 450 ℃ and can cause melting of welding points of chips and upper parts, wherein the temperature of each welding point is as follows, the temperature of the chips and the substrate is 175 ℃, and the temperature of the diode, the terminal seat and the substrate is 245 ℃, so that the temperature of the substrate and the radiator is controlled below 150 ℃ in view of the minimum requirement of the above temperature, and therefore, a low-temperature preparation process of a photovoltaic device is required. Disclosure of Invention In order to overcome the problems in the prior art, the invention aims to provide a photovoltaic device preparation process with high power generation efficiency and low preparation cost. In order to achieve the above purpose, the invention provides a preparation process of a photovoltaic device, wherein the device related to the process comprises a battery module and an aluminum radiator, the battery module comprises a bypass diode, a terminal seat, a chip and a circuit substrate, and the preparation process comprises the following steps: s1, adopting a pure copper sheet with the thickness of 0.25mm, and welding and laminating the copper sheet and an aluminum radiator at 450 ℃ through a welding process; S2, welding and bonding the bypass diode and the terminal seat with the circuit substrate in an SMT mode through a medium height Wen Xigao at 245 ℃; s3, carrying out die bonding and wire bonding packagi