Adaptive four-stage charging characteristic: constant current ("bulk") phase, constant voltage ("absorption") phase, float voltage ("float") phase, storage voltage ("storage") phase The microprocessor-controlled 'adaptive' battery management system of the Phoenix charger can be adapted to different battery types. 'Adaptive' means that the charging characteristic is automatically adapted to the type of battery utilisation. The right amount of charge: adapted constant voltage time In the case of low battery discharge (e.g. a yacht connected to shore power), a short constant voltage phase is selected to prevent overcharging. After a deep discharge, the constant voltage phase is automatically extended to ensure that the battery is fully charged. Preventing damage due to excessive gassing: the battery protection mode In order to shorten the charging time, the highest possible charging current was selected together with a high constant voltage. However, to prevent excessive gassing towards the end of the constant current phase, the Phoenix charger limits the speed of the voltage increase after the gassing voltage has been reached. Less maintenance and ageing when the battery is at rest: storage mode Storage mode is always activated if no discharge has taken place within 24 hours. In storage mode, the charge retention voltage is then reduced to 2.2 V/cell (13.2 V for a 12 V battery) in order to minimise gassing and corrosion on the positive plates. Once a week, the voltage is increased to the level of the gassing voltage. This achieves a kind of equalising charge that prevents electrolyte stratification and sulphation - the two main causes of premature battery failure.