Solar panels are mainly composed of: solar cells, photovoltaic glass, current strip, PVC, outer frame, and other materials. The most critical material is the solar cell. The main function of solar cells is to convert light energy into electricity, a phenomenon called the photovoltaic effect. Among the many solar cells, the more conventional ones are monocrystalline silicon solar cells and polycrystalline silicon solar cells.
In sunny areas, it is better to use polycrystalline solar cells because the production process of polycrystalline solar cells is relatively simple and the price is relatively cheap. In areas with more rainy days and less sunlight, it is better to use monocrystalline solar cells because the performance parameters of monocrystalline solar cells are more stable, but of course, the corresponding manufacturing cost is more expensive than polycrystalline solar cells.
First, for any solar lights, we must first understand the solar cells, solar cells have five major electrical performance parameters:
1, It is the short-circuit current
2, is the peak current
3， Voc is the open-circuit voltage
4, Vm is the peak voltage
5, Pm is the peak power
Pm is the peak power = Im is the peak current * Vm is the peak voltage
(Note: The above formula varies according to the external characteristics of the solar cells.)
For a single solar cell, it is a PN junction, which has all the characteristics of a PN junction except that it produces electricity when sunlight shines on it. Under standard lighting conditions, it has a rated output voltage of 0.48 V. Solar panels used in solar lighting fixtures are composed of multiple solar cells connected together.
Charge & discharge controller
Regardless of the type of solar lights, a well-performing charge & discharge control circuit is essential. In order to prolong the service life of the battery, it’s charging & discharging conditions must be limited to prevent the battery from being overcharged as well as over-discharged.
In addition, because the input energy for solar panel power generation is very unstable, the control of battery charging is more complicated than the control of ordinary battery charging. For the design of solar lights, success or failure often depends on the success or failure of the charge/discharge control circuit.
Without a well-performing charge & discharge control circuit, it is impossible to have well-performing solar lights. Charge & discharge controller must be to the following characteristics.
1、Prevent reverse charging
In order to meet the better application of solar lights in practice, remote control systems, radar induction systems, etc. are also added to the charging and discharging control system.
Because the input energy of solar panel power generation is very unstable, so generally need to configure the battery to work, solar lights are no exception, must be configured with battery to work. Usually, solar lights use 32650 lithium iron phosphate batteries, 18650 ternary lithium batteries.
32650 lithium iron phosphate battery is a lithium-ion battery with lithium iron phosphate as the cathode material. Lithium-ion battery cathode materials are mainly composed of lithium cobaltate, lithium manganate, lithium nickelate, ternary materials, lithium iron phosphate, and so on.
Among them, lithium cobaltate is currently the majority of lithium-ion battery cathode material lithium iron phosphate crystals in the P-O bond is stable, difficult to decompose even at high temperatures or overcharge degree charging will not collapse the structure of heat or the formation of strong oxidizing substances, so it has good safety.
32650 lithium iron phosphate battery conventional parameters for 3.2V or 6.4V.
18650 type ternary lithium battery is more commonly used in electronic products, often used as a battery cell in the laptop computer. The definition of its model law is: such as 18650 type, that is, the diameter of the battery is 18mm, the length of 65mm cylindrical type of battery. As the battery industry continues to develop, there are square batteries, 22650 lithium batteries, etc., on the battery follow-up, we will write a special article to introduce.
We know that the lamp mainly consists of two parts: electricity and light, and the light source is an important part of the solar lihgts. Its role is: through the control system and power supply system to convert electrical energy into light energy, irradiation to the surface of the object so as to achieve the purpose of lighting.
The light source of solar lights generally consists of an aluminum substrate and LED. LED is usually divided into SMD and COB, the SMD LED used in solar lights is usually in the form of 2835, 3030, 5730 packages. the main parameters of LED are.
4、Color rendering index
Among them, good quality LED chips not only have a better lighting effect but energy-saving and environmental protection to extend the life of the lamp. The main brands are CREE, OSRAM, Bridgelux , SANAN, SSC, etc.
Different color temperature actual effect is also different, to 3000K, 4000K, 6500K is the most widely used, according to the local weather conditions to choose the color temperature is very necessary, for example, rainy weather areas, choose 3000K or 4000K solar lights better because the low color temperature of the light penetration is stronger.
Structural components (referred to as the lamp body or housing) is the carrier that integrates the above four systems together, and also has the function of protecting each component and regulating the luminous effect.
It is generally composed of housing, mounting bracket, reflector, waterproof rubber ring, glass or PC lens, etc. Currently, the most widely used materials for solar lights are die-casting aluminum, extruded aluminum profiles, plastic. Different materials will also affect the performance of waterproof, dustproof, explosion-proof, heat dissipation.
Die-cast aluminum has the characteristics of one-piece molding, high strength, good heat dissipation, and reasonable price.
Extruded aluminum profiles are roughly the same as die-cast aluminum, the difference is that it is difficult to mold in one piece thus leading to assembly trouble, waterproof, dustproof performance is slightly worse than die-cast aluminum.
Plastic has the characteristics of integrated molding, low cost, plastic lamp body has been more and more consumers welcome in recent years.
Energy is a very important resource in today’s industrialized world. As traditional energy sources become less and less available, coupled with the ever-changing environment of the earth, new energy sources will be one of the most important needs in the future.
Lighting is an essential need for human life and work, and the application of solar energy to lighting fixtures is an important direction for the future lighting industry.
A good solar lamp not only needs the above components, but also to ensure the quality, stability, and coordination of each component, and more rigorous, scientific production and inspection processes. So choosing good solar lights is actually choosing a trustworthy manufacturer. I hope that today’s introduction will give you some understanding of solar lights.