Section 39 (Electronics - Design And Function - 1 Of 4): Battery: Terminology: Charging
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The process by which a battery is supplied with energy by a charger or the generator (GEN) in the car. During charging, the lead sulfate in the plates is converted back to pure lead on the negative plates and to lead oxide on the positive plate. Water is consumed, sulfuric acid is formed and the density of the acid increases.
This reaction can be written:
2 PbSO4 + 2 H2 O → PbO2 + Pb + 2 H2 SO4