Basic electrochemical processes
Rechargeable batteries - Lead-acid batteries

The fact that the ionic conductor is involved in the reactions at the electrodes, as we shall see, is a significant feature of the lead-acid battery. This is an aqueous sulfuric acid solution whose concentration changes during the electrochemical process. This point will be explained in greater detail later, but it should be noted that in the concentration range to be considered, the acid is not completely dissociated. Sulfuric acid dissociates in aqueous media in two stages:

• first dissociation: ${\text{H}}_2{\text{SO}}_4+{\text{H}}_2\text{O}\to {\text{H}}_3{\text{O}}^{+}+{\text{HSO}}_4^{-}$

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