|Silver Oxide is the nickname for a silver oxide-alkaline-zinc primary battery. And it's nicely priced for the dependability and power it delivers.
The image to the left is a typical Silver Oxide round battery. Additional information and a more detailed cutaway view are available by clicking on the image.
Two types of Silver Oxide batteries are available, one type with a sodium hydroxide (NaOH) electrolyte and the other with a potassium hydroxide (KOH) electrolyte. Sodium hydroxide types last two to three years making them highly suitable for quartz analog digital watches or digital watches without backlights. Potassium hydroxide types are better for the short bursts of higher current drains that are required from LCD watches with backlights. Hearing aids and electronic measuring instruments also use batteries with a potassium hydroxide electrolyte in combination with a special separator to match the application.
The Silver Oxide battery has a higher closed circuit voltage than a Mercuric Oxide battery and a flatter discharge curve than the Alkaline Manganese Dioxide battery.
The current delivery capabilities of a Silver Oxide cell are determined by the type of electrolyte used, as shown in the chart at the left. Like the Mercuric Oxide cell, when the potassium electrolyte is used, the cell offers less resistance to current flow. This allows the cell to operate at a higher efficiency under heavier current drains. At low current drains, both the sodium hydroxide (NaOH) and potassium hydroxide (KOH) electrolyte operate with the same efficiency.
The open circuit voltage is 1.6 volts. With current drain it is typically 1.5 volts or more. Silver Oxide cells exhibit a very flat operating voltage discharge curve that has a higher voltage than Mercuric Oxide cells. The chart to the right illustrates this comparison.
Silver Oxide Battery Characteristics
|| Zn + Ag2O KOH --> ZnO + 2Ag
Zn + Ag2O NaOH --> ZnO + 2Ag
||32║ F to 130║ F (0║ C to 54.4║ C) with KOH electrolyte.
NaOH electrolyte operates less well at low temperatures.
||Hearing aids, watches, calculators, photoelectric exposure meters, instruments, and pagers.
||Low internal resistance. KOH electrolyte is lower than with NaOH electrolyte.
||Loses less than 10% after 5 years.
||-40║ F to 150║ F ( -40║ to 60║ C)
||Not recyclable; check with your local authority (city/county/parish) for proper disposal.