A lead‐acid battery stored in an acid‐starved condition, rather than in a totally flooded state, shows a well‐behaved and predictable decline in open‐circuit voltage with time. The voltage‐time curves of such batteries can be used to determine the rates of the predominant self‐discharge reactions and to study the reaction mechanisms. An abrupt change in the slope of the curve indicates a change in the dominant self‐discharge process. Acid‐starved automotive (SLI) batteries with antimonial‐lead grids show a slope change at 1.85 V/cell. This apparently corresponds to a change in the grid corrosion mechanism. Measurements of gas evolution from these SLI batteries show that the rate of hydrogen evolution is dependent on the acid concentration whereas the rate of evolution of carbon dioxide is independent of acid concentration. Oxygen reacts rapidly at the negative plate.

It is shown that in a structurally controlled lead-acid cell the electrodes, in addition to their electrochemical function, also provide evolved gas recombination sites. The reaction kinetics and the transport properties in the acid electrolyte solution are making the process possible at practical rates. Typical recombination rates for oxygen are of the order of 15 mA/cm 2 (C/10). For hydrogen, the observed starting rate of recombination exceeds self-discharge evolution in a lead-calcium system by a factor of at least 30. A review of various operational characteristics is given including half-cell potentials, cell voltages, internal pressures, and hydrogen partial pressures.

Es wird gezeigt, daß bei bestimmter Wahl der Strukturparameter einer Blei‐Säure‐Zelle die Elektroden, zusätzlich zu ihrer elektrochemischen Funktion, auch Rekombinationsplätze für das entwickelte Gas bilden.

Kurven der Batteriespannung als Funktion der Zeit werden zur Untersuchung der Selbstentladungsreaktionen in Pb‐H, SO4‐KFZ‐Batterien benutzt.