Sometimes a mistake may happen…. This photo shows a ZG-LFP 20AH cell that has a reversed polarity marking. The problem was cased during the final part of the production, as the outer sleeve with the polarity symbols (plus/minus signs) was put in opposite direction.  The cell is completely OK, only the marking is reversed. 

This real situation shows that even after a multiple checking of the production, a faulty product may slip out. This case also shows the need for the final responsibility of checking during the installation of the cells. There is always need to check everything to the very last detail and not relying just on signs and marking. 

In this case we have honored the warranty and replaced the cell with another new cells with proper marking.