HIT (Heterojunction In-line) solar cells refer to silicon solar cells that employ a HIT structure. The HIT structure involves depositing two layers of undoped (intrinsic) hydrogenated amorphous silicon on a crystalline silicon wafer: one undoped (intrinsic) hydrogenated amorphous silicon and the other doped with the opposite type of doping. This process improves the performance of the PN junction, resulting in a conversion efficiency exceeding 25% and an open-circuit voltage of 729mV. Furthermore, the entire process can be implemented below 200°C.
Compared to traditional crystalline silicon technology, HIT (heterojunction) solar cells utilize amorphous silicon thin films. The front and back surfaces of the crystalline silicon substrate in HIT solar cells undergo excellent passivation treatment, resulting in increasingly sophisticated and complete surface passivation processes.
Advantages of HIT heterojunction solar cells
1. Wide range of applications: HIT heterojunction solar cells play an indispensable role in various economic fields such as solar panels, urban public transportation, communication equipment, power installation projects, national defense technology, ocean voyages, and domestic aviation.
2. High potential for efficiency improvement: The N-type silicon wafer used in HIT heterojunction cells has a higher minority carrier lifetime, and the corresponding structure with amorphous silicon passivation treatment can also achieve a lower surface recombination rate. As a result, the open-circuit voltage of silicon heterojunction solar cells is much higher than that of traditional monocrystalline silicon solar cells, and its efficiency potential is up to 2% greater than that of current PERC cells using P-type silicon wafers.
3. Low cost and simple manufacturing process: HIT heterojunction solar cells combine the advantages of ultra-low temperature manufacturing of thin-film solar cells, avoiding the high-temperature processes of traditional solar cells. The HIT process is relatively simple, requiring only four steps to complete the entire production process.
4. High stability and high efficiency: HIT heterojunction cells have good light stability. No Staebler-Wronski effect was found in the amorphous silicon thin film in the heterojunction, which means that the cell conversion efficiency will not show any signs of degradation due to light exposure.
5. Double-sided battery: HIT heterojunction battery is a very good double-sided battery. There is basically no color difference between the front and back sides, and the bifaciality (referring to the ratio of the efficiency of the back side of the battery to the efficiency of the front side) can reach more than 90%, and can reach as high as 98%. The core competitiveness of the back side power generation is obvious.
2. Discharge
Emergency energy storage vehicles or megawatt-level stationary energy storage stations are specially designed with output interfaces (generally, two types are designed according to user requirements: high-power three-phase output interface and conventional single-phase output socket).
3. Maintenance
Normally, you only need to check the parameters of each individual cell on the lithium-ion battery management system display screen; no manual maintenance is required. The battery management system features a visible capacity display, voltage display, and displays of the temperature and minimum or maximum voltage of each individual cell.
