The can of an Edison cell is steel, nickel-plated. Naturally cells of this sort are more costly than lead cells--and they are much bulkier because Edison cell is capable of producing an e.m.f. of only little more than half that of the lead cell.
A.C. GENERATORS
While electricity from chemicals is of great importance in modern life, by far the most important and most widely used method of “producing” electricity is by means of generators, which involves the conversion of mechanical energy into electrical
Fig. 14--A hydrometer used for determining the condition of a storage battery.
Fig. 15--Cut-away view of an assembled Edison cell.
energy. To supply the mechanical energy, steam engines are commonly used, and then the energy in coal goes through several conversions, finally resulting tin the production of electricity.
The use of water power as the provider of mechanical energy for the production of electricity is getting to be very general--and in this case there is a conversion of water pressure, to mechanical force, to electric pressure (e.m.f.).
