💏intro to chemistry review

Lead acid battery

Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025

Definition

A lead acid battery is a type of rechargeable battery that uses lead dioxide and sponge lead for its electrodes, with sulfuric acid as the electrolyte. It is commonly used in automotive applications and uninterruptible power supplies.

5 Must Know Facts For Your Next Test

  1. Lead acid batteries operate based on the chemical reaction between lead dioxide (PbO2), sponge lead (Pb), and sulfuric acid (H2SO4).
  2. During discharge, lead dioxide and sponge lead are converted into lead sulfate (PbSO4) while generating electrical energy.
  3. The overall cell reaction can be represented as: $$\text{PbO}_2 + \text{Pb} + 2\text{H}_2\text{SO}_4 \rightarrow 2\text{PbSO}_4 + 2\text{H}_2\text{O}$$.
  4. Lead acid batteries have a nominal voltage of approximately 2 volts per cell, with typical car batteries having six cells to produce a total of 12 volts.
  5. They are known for their high surge currents, making them ideal for engine starting applications.
2,589 studying →