Diamond wire slicing technology
The cutting process of crystalline silicon material accounts for a high proportion of non-silicon cost in the photovoltaic industry. Diamond wire cutting is a new technology of cutting processing, which is to fix the diamond wire by bonding and electroplating the diamond on the straight steel wire. Perform high speed round-trip cutting. The cost of the diamond wire slice is lower than that of the conventional mortar slice, and the cost of the mono crystal diamond wire slice is slightly lower than that of the polycrystalline diamond wire slice. At present, mono-crystal sections have basically been popularized with diamond wire slices, and polycrystalline is rapidly transitioning from the mortar slice to the diamond wire slice.
PERC PV cells (passivated emitter and back battery technology)
The biggest difference between this technology and the conventional solar cell is that the back surface dielectric film is passivated, and the local gold PERC cell is contacted, which effectively reduces the electron recombination speed of the back surface, and at the same time improves the light passivation emission reflection of the back surface. In terms of market, at the end of 2018, the global PERC solar cell production capacity is about 70GW, and the annual PERC solar cell production exceeds 55GW in 2018. It is expected that the global PERC PV cell production capacity will be close to 100GW by the end of 2019. PERC photovoltaic cells will be further stable and efficient in the next few years and become the mainstream position of photovoltaic cell products.
“King Kong line + black silicon” technology
Black silicon technology refers to: A surface veneering process is added to the surface of the conventional texturing process with high reflectivity and obvious line marks, which reduces the surface reflectance, thereby improving the light absorption capacity of the silicon wafer and the efficiency of the solar cell. The dry black silicon technology is stable and mature, the suede structure is uniform, and the efficiency is the highest, but new equipment and processes with higher costs are needed. Limited by the high capital expenditure of equipment, dry black silicon technology is currently mainly mass production in some tier-one solar cell manufacturers, such as JA, Jinko, GCL, and CECEP, and there is still room for further development. The new cost of wet black silicon technology is relatively small, and the efficiency can be increased by 0.3%-0.5%.
Double-sided photovoltaic cell technology
Double-sided solar photovoltaic cells are one of the other key breakthrough technologies for PV companies in recent years. Compared with conventional solar cells, this type of photovoltaic cells mainly add double-sided paste printing and boron doping (such as spin coating, printing high temperature propulsion and solid source diffusion). This type of photovoltaic cell also features both sides to absorb incident light, thereby increasing the amount of electricity generated by photovoltaic cells and solar modules. Taking a double-sided dual-core mono-crystal 72-piece photovoltaic module as an example, depending on the actual power generation environment, the backside overflow is about 10%-25%, and the power generation capacity is increased up to 25%. In the recent years, N-type single crystal double-sided photovoltaic cell modules have gradually released production capacity.
The technology uses 12 grid lines. The grid lines enhance the current collection capability while reducing the internal loss of the photovoltaic cells and increasing the effective light-receiving area, so that the solar module power is increased by at least one gear (5W). In addition, MBB different from the design of the main grid wire and the solder ribbon of the traditional photovoltaic cell, the 12-gate design effectively reduces the residual stress of the gate line, and finally the probability of cracking of the photovoltaic cell component is greatly reduced. Moreover, due to the small gap between the grid lines, the probability of cracking and chipping of the solar cell sheet is greatly reduced.
Stack solar photovoltaic technology
Using the slicing technology to redesign the grid lines to cut the solar cells into small pieces of reasonable shape, each small piece of solar cells is superimposed and arranged, welded and fabricated into strings, and then serially and vertically formatted and laminated into photovoltaic modules, thus making solar cells Connect to each other in a tighter way. Under the same use area, laminated solar panels can place more than 13% more photovoltaic cells than conventional photovoltaic modules, and due to the optimization of the structure of the solar modules, the use of a solderless strip design greatly reduces the line loss of the solar panels. Ultimately, the output power of the solar module is greatly improved. This technology has the advantage of higher efficiency and lower loss. Stack technology will undoubtedly revolutionize the encapsulated technology of China’s efficient solar module manufacturers.
Half-chip photovoltaic cell technology
The half-piece solar cell module cuts the traditional photovoltaic cell in series, reduces the current mismatch loss, reduces the current loss inside the photovoltaic module, and the output power is about 10w higher than the same size of the whole photovoltaic cell assembly, and the hot spot temperature is about 25C lower than the temperature of the same size solar cell module.