ABSTRACT
When manufacturing PV modules, the low individual power output of solar crystalline cells means that the solar cells are first connected in series (cell stringing). The front contacts of each cell are soldered with the back contacts of the next cell. Some manufacturers already use lead-free solder or lead-free connections. By connecting the negative pole (front) of each cell with the positive pole (back) of the following cell, the cells are connected in series. The individual cells are spaced several millimetres apart. Back-contacted solar cells are easy to connect together since strings are formed entirely on the back of the cells. This allows the cell spacing to be much smaller.
