In order to shorten the loading time, the highest possible charging current was selected together with a high constant voltage. However, in order for an excessive gas development to be avoided towards the end of the constant trump phase, the charger limits the speed of the voltage climb after the gas voltage has been reached. (See loading curve between 14.4 V and 15.0 V in Figure 2.) The warehouse mode is always activated if no discharge has been carried out within 24 hours. In storage mode, the loading tension is then reduced to 2.2 V/cell (13.2 V for a 24 V battery) in order to minimize gas development and corrosion on the positive plates. Once a week, the voltage is increased to the level of the gas voltage. This achieves a kind of compensation charge that prevents the electrolystal lay.
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