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How do oxidation-reduction reactions produce electric current in batteries?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

Batteries produce electric current by spatially separating the two halves of an oxidation-reduction reaction—a process where electrons are transferred from a reducing agent to an oxidizing agent.123

In a battery, these reactions occur at two separate electrodes:
* Anode: The reducing agent (typically a metal) undergoes oxidation, giving up electrons.43
* Cathode: The oxidizing agent (often a metal oxide or sulfide) undergoes reduction, accepting electrons.43

Because the oxidation and reduction processes are physically separated, the electrons released at the anode cannot transfer directly to the oxidizing agent. Instead, they are forced to travel through an external circuit to reach the cathode, creating a flow of electric current. To maintain the circuit and balance the flow of charge, an electrolyte within the battery allows ions to migrate between the electrodes, completing the internal path for the chemical reaction.1354

This separation of redox processes converts chemical energy into electrical energy, providing the driving force (voltage) necessary to power external devices.15