This video presentation is represented by electrical4u.com
An online electrical engineering study site. Let us discuss about zinc carbon battery
This was first experimentally demonstrated by French scientist Georges Leclanche. This is known as Leclanche cell, and it was invented, and patented by him in 1866
In this battery cell, one glass jar was used as main container
The container was filled with ammonium chloride solution as electrolyte. In this battery cell, a porous pot was filled with one to one mixture of manganese dioxide
and carbon powder. A carbon rod was inserted into this mixture. The porous pot along with this mixture and carbon rod served as positive electrode, or
cathode and this was placed in the ammonium chloride solution in the jar
A zinc rod was immersed in this electrolyte, as negative electrode, or anode
In Leclanche battery cell, zinc is used as anode, manganese dioxide is used as cathode
and ammonium chloride is used as electrolyte. During discharge, zinc anode involves in oxidation reaction, and each zinc atom, involved in
this reaction releases two electrons. That is, Zn becomes Zn2 plus and two electrons these electrons come to the cathode through
external load circuit. In Leclanche battery cell, ammonium chloride exists in electrolyte mixture as NH4 plus
and Cl minus ions. In cathode, manganese dioxide will be reduced to Mn2O3 in reaction with ammonium ion
In addition to Mn2O3 this reaction also produces ammonia and water. Overall reaction is, Zn, plus 2 MnO2, plus 2 NH4Cl, equals Mn2O3, plus Zn with end bracket
NH3, 2, Cl2, plus H2O. Standard voltage rating of a zinc carbon battery is determined by type of anode and cathode
materials used in the battery cell. In zinc carbon battery cell, zinc is anode material and manganese dioxide is cathode
material. Electrode potential of zinc is minus 0.76 volt whereas electrode potential of manganese
dioxide is 1.23. Therefore, theoretical voltage of each cell should be minus minus 0.76 plus 1.23 equals
1.99 V but considering many practical conditions, the actual voltage output of a standard zinc
carbon battery is not more than 1.5 volt. Thank you. Hope, you got a clear and basic idea
So, please do not forget to watch more technical video presentation, and many more, in electrical4u.com