Leclanché Cell

 

The original consumer battery the Leclanché cell was invented and patented in 1866 by Georges Leclanché.
	It consisted of a glass jar containing a porous pot with a central carbon element surrounded by powdered manganese dioxide. This formed the positive electrode. The negative electrode being a zinc rod standing in the jar which was half-filled with ammonium chloride solution, thickened by the addition of sand or sawdust. By 1868 20,000 such cells were in use and this original design, with little alteration, continued in use for nearly a hundred years.
Disadvantages included its weight and bulk, the breakable glass container and the possibility of dangerous spillage.