HJT battery, also known as heterojunction battery, is a special PN junction, which is composed of amorphous silicon and crystalline silicon. It is an N-type battery in which an amorphous silicon film is deposited on crystalline silicon.

HIT (heterojunction with intrinsic thin film) battery was first developed by Sanyo Company of Japan in 1990. Because HIT has been registered as a trademark by Sanyo, it is also called HJT, HDT or SHJ.

The laboratory efficiency of HIT battery reaches more than 26%, and the average mass production efficiency of existing mainstream manufacturers reaches 23%. In terms of efficiency, it is indeed a step higher than PERC battery. HJT battery technology is very simple.

At present, PERC, the mainstream battery technology in the market, needs 8- 10 processes, while HJT process has only 4 processes, namely, cleaning and texturing, amorphous silicon film deposition, TCO film preparation and screen printing. Among them, cleaning, texturing and screen printing are all traditional silicon battery processes, while HJT's unique process is used for amorphous silicon film deposition and TCO film deposition.