How does solar cell work?

Solar batteries have many practical applications. They are particularly suitable for areas where grid access is difficult to reach such as high mountains, beyond islands, or serving space operations; specifically, satellites orbiting the earth orbit, handheld computers, remote cell phones, pumping equipment .

What is solar battery? How does it work?

Solar batteries ( solar cells / photovoltaic batteries) are devices that directly convert sunlight energy ( solar energy) into electrical energy (electricity) based on the photoelectric effect. The photoelectric effect is the ability to emit electrons when light is illuminated by matter.

Solar panels, large surface panels that collect sunlight and turn it into electricity, are made of many photovoltaic cells that perform the process of generating electricity from sunlight.

Semiconductors

Silicon is known as a semiconductor. "Semiconductors are intermediate materials between conductors and insulators. Semiconductors act as an insulator at low temperatures and conductivity at room temperature." With such properties, silicon is an important component in the construction of solar cells.

Silicon has a limited electrical conductivity but it has a very fine crystalline structure for making semiconductors. The silicon atom needs four electrons to neutralize the charge, but the outer shell of a silicon atom has only half of the electrons needed, so it will adhere to other atoms to find a way to neutralize the charge.

To increase the conductivity of silicon, scientists have ' implicated ' it by combining it with other materials. This process is called ' doping ' and silicon doped with impurities creates more free electrons and holes. A silicon semiconductor has two parts, each of which is doped with another material. The first part is mixed with phosphorus , phosphorus needs 5 electrons to neutralize the charge and has enough 5 electrons in its shell. When combined with silicon, an electron will be redundant. Electrons are specific to negative charges, so this part will be called N-type silicon (N electrode). To create P-type silicon (P electrode), scientists combine silicon with boron . Boron only needs 3 electrons to neutralize the charge and when combined with silicon it will create holes that need to be filled with electrons.

When silicon semiconductors are exposed to energy, free electrons at the N-electrode will move to fill the holes on the electrode P. Then the electrons from the N-electrode and the P-electrode will be together. create electric field. Solar cells will become a diode , allowing electrons to travel from the P-electrode to N-electrode, not allowing reverse movement.

Of course, to activate the process requires energy to contact the silicon cells.Sunlight consists of very small particles called photons emitted from the sun, small particles of energy that can come into contact with solar cells and loosen the bonding of electrons at the N electrode. The movement of free elentrons from N-electrode to P-electrode creates an electric current.

When the electric field is created, all we need to do is collect and convert it into usable current. An inverter attached to solar cells will turn DC current (DC) into alternating current (AC). Alternating current is the current we are using everywhere.

Current solar cells are still ineffective

Technologies that turn sunlight into electricity are still ineffective. Solar panels have not been able to absorb all the energy of sunlight. In general, the best solar cells currently can only transfer 25% of the energy it receives into electricity. Why so? The fact that sunlight, like all other types of light, consists of a spectrum with different wavelengths, each with a different intensity. There are too weak wavelengths that cannot release electrons and some wavelengths are too strong for silicon.

Moreover, solar panels should be placed in extremely special positions. The angle of the solar panels needs to be calculated in order to get the maximum amount of sunlight and of course solar panels are only really useful if placed in a place with lots of sunlight. Placing solar panels in sunny, sunny places will turn them into ridiculous and expensive artworks.

Black silicon can create a revolution in the solar cell industry

Scientists are still studying to develop more efficient solar panels. Solar cells are thin films, produced from cadmium , much thinner than silicon cells and are better able to absorb solar energy. But right now, the ability to convert the collected energy into cadmium solar cell electricity is still quite poor. However, scientists want to learn more about this type of solar cell because they are cheap and convenient.

One of the other major innovations worth mentioning is ' black silicon '. Black silicon is a processed silicon that has a black surface because black absorbs light better.

Black silicon will create solar cells that are better absorbable, especially in areas of low light or often exposed to low-light sunlight. The biggest drawback at the moment is that the process of creating black for silicon increases its surface area, which increases the recombination ability of electrons. Free electrons will search for recombination with silicon cells rather than moving to join another atom to create an electric current.

The process of studying black silicon is still ongoing. Recently, Finnish scientists have found a way to reduce recombination cases, increasing the ability to convert sunlight into electricity to 22.1%. This level of metabolism is still not as typical as silicon but it will certainly be improved in the future.

1. Spray batteries turn all surfaces into solar cells
2. Solar batteries will be usable at night