Experimental procedures are exposed that allow quantitative conclusions about the use of alternate mode (alternation of constant current charge and open-circuit periods) instead of floating mode (constant voltage condition) in standby applications of VRLA batteries. The level of capacity and the rate of a recharge following a discharge period are particularly studied. The influence of the three parameters of an alternate mode, that is to say the charging current, the maximum and minimum voltages, is especially discussed, with regard to the previously described responses.