What are the characteristics and advantages of photovoltaic heterojunction cells?
HJT heterojunction cell subverts the traditional cell structure, and has the advantages of high conversion efficiency, simple manufacturing process, thin silicon wafer application, low temperature coefficient, no-light attenuation and potential attenuation, double-sided power generation, etc., while the advantages of heterojunction components in conversion efficiency, significantly more than PERC. PERC is 10 percent less efficient than the heterojunction, meaning that the heterojunction will generate 10 percent more power than PERC over the entire power cycle of the same battery component.
Characteristics and advantages of heterojunction cell (HJT cell)
1. No PID phenomenon: Since the upper surface of the battery is TCO, the charge will not produce polarization phenomenon on the TCO of the battery surface, and no PID phenomenon. At the same time the measured data also confirmed this point. Application and prospect of heterojunction solar cells
2, low temperature manufacturing process: HJT battery corner stone processing temperature is below 250, to avoid the low production efficiency and high cost of high temperature diffusion process of the system, the and low temperature process makes a – Si thin film optical band gap, deposition rate, absorption coefficient and hydrogen content to get more precise control, also can avoid the high temperature thermal stress caused by the adverse effects, etc.
3, high efficiency: HJT battery has been refreshing the world record of mass-produced battery conversion efficiency. HJT cells are 1-2% more efficient than P-type monocrystalline silicon cells, and the difference is slowly increasing.
4. Technical application and prospect of heterojunction solar cells with high illumination stability: Staebler-Wronski effect common in amorphous silicon solar cells will not appear in HJT solar cells. At the same time, the N-type silicon wafer used by HJT battery is doped with phosphorus, which almost causes attenuation phenomenon without light.
5, to thin development: HJT battery process temperature is low, the upper and lower surface structure is symmetrical, no mechanical stress generation, can smoothly achieve thin; In addition, for n-type silicon substrates with higher lifetime (SRV<100cm/s), the thinner the wafer, the higher the open circuit voltage can be obtained.
Although the technology of heterojunction solar cell is so good, it has not been widely used in the market at present. The main reason is the cost factor. One is the high price of production equipment, and the other is expensive consumables.
The power of a photovoltaic module is equal to the product of the effective cell area, solar radiation intensity and cell efficiency in the module. As a result, replacing PERC cells with heterojunction cells in the future will result in more powerful components, resulting in lower costs per watt and per kilowatt for power investors.