Lithium Manganese Battery

 

Lithium manganese dioxide coin cells have a high energy density and can be made very thin. They are a 3-volt system with a flat discharge curve. Lithium cells are also found in cylindrical format often with two cells joined to form a 6-volt battery. Because of their high energy density they have found use in fully automatic cameras, especially those which require high power to drive auto focus and film winding motors. They are, of course, quite expensive.