Common Problems and Causes of Silicon Solar Cells

Common Problems and Causes of Silicon Solar Cells


Because the production capacity of crystalline silicon solar cells accounts for more than 90% of solar cells, the situation described below only represents a kind that is in the leading position in the solar cell market at this stage. A complete set of solar cell power generation systems include solar cell arrays, inverter, batteries, controller and load. Different problems are inevitably encountered during the actual operation of solar cells.
 
1. The heat spot effect of solar panels
In some specific cases, the shaded solar cell module will be regarded as a load to consume the electrical energy emitted by other photovoltaic modules irradiated by light, and the shaded part will generate heat and cause the heat spot effect. This effect severely damages the module performance, reducing the output power of the panel and shortening its lifespan. The electrical energy from the solar panel components irradiated by the light is almost completely consumed. The additional bypass diode is connected in parallel with the positive and negative poles of the battery pack to effectively prevent the damage caused by this effect.
 
Because the solar panels are usually installed outdoors in a wide and sunny place or on the roof of the house, shade occurs due to stooping of birds, droppings, dust accumulation and dry leaves, or partial shade happens due to improper distance design and placement in the module matrix for large solar cells in the long-term operation. If the hot spot effect generates too much heat, beyond the bearing range, the solder joints on the modules will be melted and the grid lines will be damaged; even a large area or all of the photovoltaic modules will be discarded.
 
2. Hidden cracks of the photovoltaic module
When a solar cell module is subjected to great mechanical or thermal stress, hidden cracks that are invisible to the human eye may appear in the unit module. The thin grid lines are broken due to hidden cracks. The thin grid lines cannot transmit various currents to the main grid lines, which will cause some cells or even all cells to fail to work. The occurrence of cracks in any unit module will reduce the power of the photovoltaic modules, and the cracked modules will work for too long under load, which may generate heat, cause the hot spot effect, burn the solar cell module, and affect the service life of the modules.
 
In the manufacturing process of modules, due to defects such as welding slags, foreign matter and contact welding in the welding process, excessive force during cleaning and transmission may cause cracks; back and forth transportation and bumped roads will cause the module to tilt and deform during transportation, resulting in cracks. In the installation process, unpacking, manual transportation and stepping may cause the components to have a hidden crack. During operation and maintenance, excessive cleaning and violence may cause the module to have a hidden crack.
 
3. Snail patterns
Snail patterns containing Ag substance refer to the appearance of dark lines and vertical and horizontal distribution on the surface of photovoltaic modules, like the traces of snails crawling, also known as lightning patterns, earthworm patterns or worm patterns, which mostly appear in hidden cracked parts and edges. However, at present, there is still a lack of in-depth exploration and proof on the specific formation principle of snail patterns, and the issue of the influence of snail patterns on photovoltaic modules has been controversial.