335-355W C6-Series Mwt Monocrystalline Silicon High-Efficiency Solar Panel

Structure and composition
1) Tempered glass
Its function is to protect the main body of power generation (such as cells), and the selection of light transmission is required. 1. The light transmission rate must be high (generally more than 91%); 2. Ultra-white tempered treatment
2) EVA
It is used to bond and fix the tempered glass and the main body of power generation (such as cell). The quality of transparent EVA material directly affects the life of the module. The EVA exposed to the air is easy to age and yellow, which affects the light transmittance of the module. In addition to the quality of EVA itself, the power generation quality of the module is also very affected by the lamination process of the module manufacturer. Component life.
3) Cells
The main function is to generate electricity. The mainstream in the main power generation market is crystalline silicon solar cells and thin-film solar cells, both of which have their own advantages and disadvantages. Crystal silicon solar cells have relatively low equipment costs, but the consumption and cell costs are high, but the photoelectric conversion efficiency is also high, which is more suitable for power generation under outdoor sunlight; thin-film solar cells have relatively high equipment costs, but consume and battery The cost is very low, but the photoelectric conversion efficiency is more than half that of the crystalline silicon cell, but the low light effect is very good, and it can generate electricity under ordinary light, such as the solar cell on the calculator.
4) EVA
solar panel
The function is as above, mainly bonding and packaging the main body of the power generation and the backplane
5) Backplane
Function, sealing, insulation, waterproofing (usually TPT, TPE and other materials must be resistant to aging, most component manufacturers have a 25-year warranty, tempered glass, aluminum alloy is generally no problem, the key lies in whether the backplane and silica gel can achieve Require.)
6) Aluminum alloy
Protect the laminate, play a certain role in sealing and supporting
7) Junction box
Protect the entire power generation system and act as a current transfer station. If the component is short-circuited, the junction box will automatically disconnect the short-circuit battery string to prevent the entire system from being burned. The most important thing in the junction box is the selection of diodes. Depending on the type of cell in the assembly, the corresponding diodes are also different.
8) Silica gel
The sealing function is used to seal the junction between the component and the aluminum alloy frame, and the component and the junction box. Some companies use double-sided adhesive tape and foam instead of silica gel. Silicone is widely used in China. The process is simple, convenient, easy to operate, and the cost is very low.

Material classification
Crystalline silicon materials (including polycrystalline silicon and monocrystalline silicon) are the most important photovoltaic materials, with a market share of more than 90%, and will remain the mainstream materials for solar cells for a long period of time in the future. The demand for polysilicon mainly comes from semiconductors and solar cells. According to different purity requirements, it is divided into electronic grade and solar grade. Among them, electronic grade polysilicon accounts for about 55%, and solar grade polysilicon accounts for 45%.
Crystalline silicon solar cells: polycrystalline silicon solar cells, monocrystalline silicon solar cells.
Amorphous silicon panels: thin-film solar cells, organic solar cells.
Chemical dye panels: dye-sensitized solar cells.
Flexible solar cell

Monocrystalline silicon
The photoelectric conversion efficiency of monocrystalline silicon solar cells is about 18%, and the highest is 24%. This is the highest photoelectric conversion efficiency of all types of solar cells, but the production cost is so large that it cannot be widely used. Since monocrystalline silicon is generally encapsulated with toughened glass and waterproof resin, it is durable and has a service life of up to 25 years.

Polysilicon
The production process of polycrystalline silicon solar cells is similar to that of monocrystalline silicon solar cells, but the photoelectric conversion efficiency of polycrystalline silicon solar cells has to be reduced a lot, and its photoelectric conversion efficiency is about 16%. In terms of production cost, it is cheaper than monocrystalline silicon solar cells, the materials are simple to manufacture, the power consumption is saved, and the total production cost is lower, so it has been developed in a large amount. In addition, the service life of polycrystalline silicon solar cells is shorter than that of monocrystalline silicon solar cells. In terms of cost performance, monocrystalline silicon solar cells are slightly better.

Amorphous silicon
Amorphous silicon solar cell is a new type of thin film solar cell that appeared in 1976. It is completely different from monocrystalline silicon and polycrystalline silicon solar cells. The process is greatly simplified, the silicon material consumption is low, and the power consumption is lower. The advantage is that it can generate electricity in low light conditions. However, the main problem of amorphous silicon solar cells is that the photoelectric conversion efficiency is low, the international advanced level is about 10%, and it is not stable enough. As time goes by, its conversion efficiency decays.

Multiple compounds
Multi-compound solar cells refer to solar cells that are not made of a single element semiconductor material. There are many kinds of researches in various countries, most of which have not been industrialized. The main ones are as follows: a) cadmium sulfide solar cells b) gallium arsenide solar cells c) copper indium selenium solar cells (new multi-element band gap gradient Cu(In, Ga) Se2 thin-film solar cell)
Cu(In, Ga)Se2 is a kind of solar light absorbing material with excellent performance. It has a gradient energy band gap (the energy level difference between the conduction band and the valence band). It can expand the solar energy absorption spectrum range and improve the photoelectric conversion. efficiency. Based on it, thin-film solar cells with significantly improved photoelectric conversion efficiency than silicon thin-film solar cells can be designed. The achievable photoelectric conversion rate is 18%. Moreover, this type of thin-film solar cell has no performance degradation effect (SWE) caused by light radiation. Its photoelectric conversion efficiency is about 50~75% higher than that of commercial thin-film solar panels. Solar cells have the highest level of photoelectric conversion efficiency in the world.

Flexible battery
Flexible thin-film solar cells are distinguished from conventional solar cells.
Conventional solar cells are generally structured with EVA material and solar cells between two layers of glass. Such components are heavier and require a support during installation and are not easy to move.
Flexible thin-film solar cells do not need to use glass backsheets and cover plates, and are 80% lighter than double-glazed solar cell components. Flexible cells using pvc backsheets and ETFE thin film cover plates can even be bent arbitrarily, which is convenient to carry. There is no need for special brackets during installation, and it can be easily installed on the roof and used on the top of a tent.
The disadvantage is that the photoelectric conversion efficiency is lower than that of conventional crystalline silicon modules.

Application field
1. User solar power: (1) Small power supplies ranging from 10-100W, used in remote areas without electricity, such as plateaus, islands, pastoral areas, border posts, and other military and civilian life electricity, such as lighting, TV, radio cassette recorders, etc.; (2) 3 -5KW home roof grid-connected power generation system; (3) Photovoltaic water pump: solve the problem of drinking and irrigation in deep water wells in areas without electricity.
2. Transportation: such as navigation lights, traffic/railway signal lights, traffic warning/sign lights, Yuxiang street lights, high-altitude obstruction lights, highway/railway wireless phone booths, power supply for unattended road teams, etc.
3. Communication/communication field: solar unattended microwave relay station, optical cable maintenance station, broadcasting/communication/paging power system; rural carrier telephone photovoltaic system, small communication machine, soldier GPS power supply, etc.
4. Petroleum, marine and meteorological fields: cathodic protection solar power systems for oil pipelines and reservoir gates, life and emergency power supplies for oil rigs, marine testing equipment, meteorological/hydrological observation equipment, etc.
5. Lamp power supply: such as garden lights, street lights, portable lights, camping lights, climbing lights, fishing lights, black lights, tapping lights, energy-saving lights, etc.
6. Photovoltaic power station: 10KW-50MW independent photovoltaic power station, wind-solar (diesel) complementary power station, various large parking plant charging stations, etc.
7. Solar building: The combination of solar power generation and building materials will enable future large-scale buildings to achieve power self-sufficiency, which is a major development direction in the future.
8. Other areas include: (1) Supporting vehicles: solar vehicles/electric vehicles, battery charging equipment, automotive air conditioners, ventilators, cold drink boxes, etc.; (2) Solar hydrogen production and fuel cell regenerative power generation systems; (3) Sea water Desalination of equipment power supply; (4) Satellites, spacecraft, space solar power stations, etc.

Principle of power generation
A solar cell is a device that responds to light and can convert light energy into electricity. There are many kinds of materials that can produce photovoltaic effect, such as: single crystal silicon, polycrystalline silicon, amorphous silicon, gallium arsenide, indium copper selenide and so on. Their power generation principles are basically the same, and now take crystalline silicon as an example to describe the process of photovoltaic power generation. P-type crystalline silicon can be doped with phosphorus to obtain N-type silicon, forming a P-N junction.
When the light irradiates the surface of the solar cell, part of the photons are absorbed by the silicon material; the energy of the photons is transferred to the silicon atoms, causing the electrons to undergo transitions, becoming free electrons, gathering on both sides of the PN junction to form a potential difference. When the circuit is connected to the outside Under the action of this voltage, there will be a current flowing through the external circuit to produce a certain output power. The essence of this process is: the process of converting photon energy into electrical energy.
1. Solar power generation There are two methods of solar power generation, one is the light-heat-electric conversion method, and the other is the light-electric direct conversion method.

solar panel
(1) The light-heat-electric conversion method uses solar radiation to generate electricity. Generally, a solar collector converts the absorbed heat into vapor of the working fluid, and then drives a steam turbine to generate electricity. The former process is a light-heat conversion process; the latter process is a heat-electric conversion process, which is the same as ordinary thermal power generation. Solar thermal power plants have high efficiency. However, since their industrialization is currently in the initial stage, the investment is currently high. A 1,000MW solar thermal power station requires an investment of 2 to 2.5 billion U.S. dollars, and the average investment for 1 kW is 2,000 to 2,500 U.S. dollars. Therefore, it is suitable for small-scale special occasions, and large-scale utilization is very economically uneconomical, and it cannot compete with ordinary thermal power plants or nuclear power plants.
(2) Light-to-electricity direct conversion method This method uses the photoelectric effect to directly convert solar radiation energy into electrical energy. The basic device of light-to-electricity conversion is solar cells. A solar cell is a device that directly converts sunlight energy into electrical energy due to the photovoltaic effect. It is a semiconductor photodiode. When the sun shines on the photodiode, the photodiode will turn the sun's light energy into electrical energy to produce Current. When many batteries are connected in series or in parallel, a square array of solar cells with relatively large output power can be formed. Solar cells are a promising new type of power source, with three major advantages of permanence, cleanliness and flexibility. Solar cells have a long lifespan. As long as the sun exists, solar cells can be invested once and used for a long time; and thermal power generation and nuclear power generation. In contrast, solar cells do not cause environmental pollution; solar cells can be large, medium and small, as large as a medium-sized power station of a million kilowatts, or as small as a solar battery pack for one household, which is unmatched by other power sources.

Power calculation
The solar AC power generation system is composed of solar panels, charge controllers, inverters and batteries; the solar DC power generation system does not include inverters. In order to enable the solar power generation system to provide sufficient power for the load, it is necessary to select various components reasonably according to the power of the electrical appliances. Take the 100W output power and use it for 6 hours a day as an example to introduce the calculation method:
1. First, calculate the number of watt-hours consumed per day (including the loss of the inverter): if the conversion efficiency of the inverter is 90%, when the output power is 100W, the actual output power required should be 100W/90 %=111W; if it is used for 5 hours a day, the output power is 111W*5 hours=555Wh.
2. Calculate the solar panel: Calculate according to the effective daily sunshine time of 6 hours, and take into account the charging efficiency and the loss during the charging process, the output power of the solar panel should be 555Wh/6h/70%=130W. Among them, 70% is the actual power used by the solar panels during the charging process.

Power generation efficiency
The highest photoelectric conversion efficiency of monocrystalline silicon solar is 24%, which is the highest photoelectric conversion efficiency of all types of solar cells. However, the production cost of monocrystalline silicon solar cells is so great that it has not been widely and universally used in large numbers. In terms of production cost, polycrystalline silicon solar cells are cheaper than monocrystalline silicon solar cells, but the photoelectric conversion efficiency of polycrystalline silicon solar cells is much lower. In addition, the service life of polycrystalline silicon solar cells is also shorter than that of monocrystalline silicon solar cells. . Therefore, in terms of cost performance, monocrystalline silicon solar cells are slightly better.
Researchers have found that some compound semiconductor materials are suitable for solar photovoltaic conversion films. For example, CdS, CdTe; III-V compound semiconductors: GaAs, AIPInP, etc.; thin-film solar cells made of these semiconductors show very good photoelectric conversion efficiency. Semiconductor materials with multiple gradient band gaps can expand the solar energy absorption spectrum, thereby increasing the photoelectric conversion efficiency. A large number of practical applications of thin-film solar cells present broad prospects. Among these multi-element semiconductor materials, Cu(In,Ga)Se2 is an excellent solar light absorbing material. Based on it, thin-film solar cells with significantly higher photoelectric conversion efficiency than silicon can be designed, and the achievable photoelectric conversion rate is 18%.

Service life
The service life of solar panels is determined by the materials of the cells, tempered glass, EVA, TPT, etc. Generally, the service life of solar panels made by manufacturers who use better materials can reach 25 years, but with the impact of the environment, solar cells The material of the board will age with time. Under normal circumstances, the power will attenuate by 30% after 20 years, and the power will attenuate by 70% after 25 years.
Production process editing Voice
Slicing, cleaning, preparation of suede, peripheral etching, removal of backside PN+ junction, preparation of upper and lower electrodes, preparation of anti-reflection film, sintering, test and classification, etc. 10 steps.
Specific manufacturing process description of solar cells
(1) Slicing: Using multi-line cutting, the silicon rod is cut into square silicon wafers.
(2) Cleaning: Use conventional silicon wafer cleaning methods to clean, and then use acid (or alkali) solution to remove 30-50um from the cut damage layer on the surface of the silicon wafer.
(3) Preparation of suede: anisotropically etch the silicon wafer with an alkaline solution to prepare suede on the surface of the silicon wafer.
(4) Phosphorus diffusion: Coating source (or liquid source, or solid phosphorous nitride sheet source) is used for diffusion to form a PN+ junction, the junction depth is generally 0.3-0.5um.
(5) Peripheral etching: The diffusion layer formed on the peripheral surface of the silicon wafer during diffusion will short-circuit the upper and lower electrodes of the battery. Use masked wet etching or plasma dry etching to remove the peripheral diffusion layer.
(6) Remove the back PN+ junction. Commonly used wet etching or grinding method to remove the backside PN+ junction.
(7) Making the upper and lower electrodes: using vacuum evaporation, electroless nickel plating or aluminum paste printing and sintering processes. First make the bottom electrode, and then make the top electrode. Aluminum paste printing is a widely used process method.
(8) Making anti-reflection film: In order to reduce the incident reflection loss, it is necessary to cover the surface of the silicon wafer with a