Dry Cell and Mercury Cell: Primary Cells: This type of cells can be used only so long as the active materials are present in the cells. Once these are consumed, the chemical reaction stops and the cell cannot be recharged or used again. The two most common primary cells are the Dry Cell and Mercury Cell. Dry Cell: It is a compact form of Leclanche Cell in which anode consists of Zn container and Cathode is a graphite rod surrounded by powdered MnO2 and carbon. The space between the electrodes is filled with a moist paste of NH4Cl and ZnCl2. … Continue reading Primary Cells- Dry Cell and Mercury Cell