As the third edition of "Handbook of Batteries" notes, Frenchman Georges Leclanche invented the precursor to the dry cell battery, the wet cell, in 1866. This battery was a momentous step towards the modern dry cell, but had its impracticalities. It was not portable and lacked a tight seal. German Carl Gassner later improved upon the wet cell design by making the first commercial dry cell battery. Particularly, he added a zinc casing to his "dry cell" battery, thus sealing it and making it much more practical and marketable.
Basic dry cell batteries are very simple. A cathode or rod of carbon is encased by a paste with very limited moisture, and sealed by an outer zinc casing. The paste, or electrolyte, is ammonium chloride or zinc chloride.
Button cell, AA, AAA, C and D are common names of dry cell batteries. These batteries are also known by their chemical makeup, for example, lithium, alkaline, and carbon zinc. Power usage, life span, voltage, size, and temperature and moisture conditions are all factors that require different types of batteries. There are also rechargeable dry cell batteries, called lithium-ion (Li-ion), nickle/cadmium (NiCd) and nickle metal hydride (NiMH). These batteries are used for power-draining applications such as cameras. Because they last longer and can be recharged, they are also beneficial to the environment due to lower quantities of waste.
Batteries have a wide degree of applications, from ordinary household use, to professional fields such as medical, military and scientific. Dry cell batteries with a long lifespan, such as lithium, are used for specialized applications, including pacemakers, while batteries with shorter lifespans, for example AA, power household flashlights and TV remotes.
The inappropriate disposal of dry cell batteries contributes to human and environmental problems. The acid in batteries can cause burns in humans, while the metals can pollute the ground and water. Environmental Health & Safety Online points out that "88 percent of the total mercury and 50 percent of the cadmium in the municipal solid waste stream" can be attributed to dry cell batteries. To reduce and control the toxins of batteries reaching the environment, the US Mercury-Containing and Rechargeable Battery Management Act became law in 1996. Talk to your local hardware supply store or municipal government for ways to responsibly turn in dead batteries for proper disposal.