In the process of using solar street lights, in order to ensure long-term and useful lighting effects, the function of solar panels must be guaranteed. If there is a failure, the use of the entire system of solar street lights will be affected. What kind of failures often occur? How to avoid and prevent it?
Hot spot problem
During the use of solar street lights, some dust, leaves and other debris will inevitably fall on the solar panel, which will form part of the shadow on the solar panel. Changes occur as a result of partial heating, and over time some significant burn-out hot spots will appear.
Constitute the result
When the solar panel hot spot effect reaches a certain level, the welding points of the panel components will be melted, the grid lines will be destroyed, and the entire panel components will be gradually damaged, which will not only seriously affect the lighting system, but at least reduce the to 10% of its life.
In the early design, when the cells of the panel are connected in series, a diode is connected in parallel, which has a good voltage dividing effect and can effectively avoid the hot spot effect of the solar panel, in addition, in the later stage, When installing, you should also pay attention to avoid installing it in a sheltered place, do not allow a little shelter, and pay attention to regularly cleaning up dust and other debris on it.
Solar panels are made of crystalline silicon. Due to the characteristics of its own crystal structure, it is easy to crack, which constitutes the cause of cracking. Essentially, there are two types, one is mechanical stress and the other is thermal stress. , initially only some small cracks will appear in the cell, which is difficult to detect with the naked eye, but after a long time, it will develop into fragments, which are visible to the naked eye at this time.
Constitute the result
When the crack causes the grid line to be thick, the collected current will not be output normally, and the result will be partial or even complete failure of the cells, which will have a great impact on the power output of the solar street light, resulting in its incorrect attenuation, and then At the same time, the cracking problem of the battery board continues to expand under the mechanical load, which may also lead to open circuit damage, which will also cause a hot spot effect.
In the process of production, transportation, installation and protection of the solar panel, it is necessary to fully consider its simple cracking characteristics, avoid hitting or kneading with hard objects, and reduce the possibility of cracking of the components.
Snail pattern problem
Solar panels tend to have some black or white linear patterns that look like the traces of a snail crawling over, which is called a snail pattern. This is often a crack in a battery component, and moisture enters the crack through the resin backplane and packaging material. This moisture will react with the silver in the desired finger electrode of the battery, resulting in the dispersion of silver ions.
At this time, through the illumination of sunlight, silver ions will chemically react with other substances to generate silver oxide and silver sulfide, and then they will form the snail pattern we see along the crack, which is actually a photovoltaic circle.
Constitute the result
In fact, the snail pattern is accompanied by the cracking problem of the battery, so the result of the composition is the same. First, the aesthetics are greatly reduced, and secondly, when the crack reaches 8% of the battery surface area, it will be damaged. The panel itself constitutes a significant adverse effect, reaching 12% of the surface area, and the function of the panel will decrease linearly, resulting in the attenuation of the power and life of the panel.
During the production, transportation, installation and protection of the solar panel, try to avoid bumping or kneading. Some manufacturers use glass packaging to replace the back panel during production, and may add a barrier layer to prevent moisture from passing through. The resin backplane can reduce the occurrence of snail patterns to a certain extent, but this time it will increase the cost.