What is a dry-cell battery?

Answer 1

A dry cell uses chemicals that are in solid or powder form, as opposed to lead acid batteries that use a liquid electrolyte. The term is generally used to refer to standard non-rechargeable batteries.

Answer 2

In dry cell battery the electrolyte is mixed with silica to hold it in a gel like consistency. In absorbed glass mat batteries the electrolyte is usually held by glass fibers and thus the electrolyte cannot leak or spill over. These are two types of dry cell batteries. In wet cell batteries the electrolyte is in liquid form, comprising a solution of dilute sulphuric acid. As electrolyte dries up it can be replenished in wet cell or flooded cell batteries but it is impossible in sealed gel batteries and difficult in AGM batteries with sealed bodies.

Answer 3

A dry cell has the electrolyte immobilized as a paste, with only enough moisture in the paste to allow current to flow. As opposed to a wet cell, the battery can be operated in any random position, and will not spill its electrolyte if inverted.

While a dry cell's electrolyte is not truly completely free of moisture and must contain some moisture to function, it has the advantage of containing no sloshing liquid that might leak or drip out when inverted or handled roughly, making it highly suitable for small portable electric devices. By comparison, the first wet cells were typically fragile glass containers with lead rods hanging from the open top, and needed careful handling to avoid spillage. An inverted wet cell would leak, while a dry cell would not. Lead-acid batteries would not achieve the safety and portability of the dry cell, until the development of the gel battery.

A common dry cell battery is the zinc-carbon battery, using a cell sometimes called the dry Leclanché cell, with a nominal voltage of 1.5 volts, the same nominal voltage as the alkaline battery (since both use the same zinc-manganese dioxide combination).

The makeup of a standard dry cell is a zinc anode (negative pole), usually in the form of a cylindrical pot, with a carbon cathode (positive pole) in the form of a central rod. The electrolyte is ammonium chloride in the form of a paste next to the zinc anode. The remaining space between the electrolyte and carbon cathode is taken up by a second paste consisting of ammonium chloride and manganese dioxide, the latter acting as a depolarize. In some more modern types of so called 'high power' batteries, the ammonium chloride has been replaced by zinc chloride.

Answer 4

Anywhere lightweight portable power is required and the risks of spilling wet cells would be unacceptable.