HJT Solar Cell and Its Advantages

HJT Solar cell is a thin film of amorphous silicon deposited on crystalline silicon. It combines the advantages of crystalline silicon cells and thin film cells. Compared with PERC, a mainstream high-efficiency photovoltaic cell, heterojunction conversion efficiency and power generation are higher.

1. Better conversion efficiency. HJT efficiency potential exceeds 28%, which is much higher than PERC cells. At the same time, HJT can be upgraded to new perovskite photovoltaic cells. From the theoretical efficiency point of view, the efficiency of single-layer perovskite can reach 31%, the efficiency of double-junction perovskite stack can reach 35%, and the efficiency of triple-junction perovskite stack can reach more than 45%.

2. The process flow is more simplified and the space for cost reduction is greater. HJT is a low-temperature process that can reduce the use of silicon wafers. It has advantages in both silicon wafer cost (facilitating thinning and reducing thermal damage) and non-silicon cost (saving fuel). At the same time, HJT only requires 4 processes. From the perspective of the complete industrial chain, compared with the PERC 8 processes and the TOPCon 9-12 processes, the cost is lower.

3. Lower light-induced attenuation. The degradation rate of HJT batteries in 10 years is less than 3%, and the power generation decline in 25 years is only 8%. The decay speed is much lower than PERC and TOPCon cells.

4. Low temperature coefficient and high stability. In an environment of 82 degrees Celsius, HJT photoelectric conversion efficiency is 13% higher than traditional modules.

5. Higher double-sided rate. HJT has a double-sided symmetrical structure, and the double-sided ratio is expected to increase to 93-98%. However, PERC and TOPCon are both around 80%, which is difficult to improve. HJT can obtain more than 10% annual power generation gain.

6. High response to low light. Under the same conditions, heterojunction can generate electricity earlier in the morning and later in the evening than PERC, effectively increasing the power generation time by about 10%.