The a-Si/c-Si Heterojunction Technology (HJT) or Heterojunction with intrinsic thin layer (HIT) solar cell have been fabricated in mass production，the average conversion efficiency of HJT solar cells with 3 bus bar, 5 bus bar and smart wire structures have reached 20%, 21% and 22% respectively. One of the biggest obstructions for HIT module manufacturing is the Cell-to-Module (CTM) stringing process where much power loss happened due to high temperature. The higher temperature in stringing process makes passivation quality worse and introduces much more defects. In this article, we present our investigation on CTM string connection methods, especially on which undergo low temperature to avoid thermal micro damage on cell’s functional structure. Several kinds of string connection are elaborated. The discussion will give some directions for further laboratory research and HJT manufacturing.