Coin cell batteries function similarly to larger batteries like AA and AAA batteries. They generate electricity through a chemical reaction between two different metals, acting as electrodes.
Coin Cell Battery Components
A coin cell battery's construction is key to understanding its operation:
- Electrodes: The battery consists of two electrodes: a cathode (positive terminal) and an anode (negative terminal). These are made of complementary metals that react chemically.
- Body: Typically, stainless steel forms the bottom body of the battery, which also serves as the positive terminal.
- Negative Terminal: The metallic top, insulated from the positive terminal, forms the negative terminal.
- Electrolyte: An electrolyte solution or paste exists between the electrodes, facilitating the movement of ions and completing the electrical circuit.
The Chemical Reaction
The core of a coin cell battery's function is a chemical reaction:
- Oxidation: At the anode (negative terminal), a metal undergoes oxidation, releasing electrons.
- Electron Flow: These electrons flow through an external circuit (powering a device) to the cathode (positive terminal).
- Reduction: At the cathode, another metal undergoes reduction, consuming the electrons.
- Ion Transport: Ions move through the electrolyte to balance the charge created by the electron flow.
This continuous chemical reaction generates a steady flow of electrons, providing electrical power. Once the reactive materials are depleted, the battery is considered dead.
