A motorist could keep a charger rated a couple of amperes to ten or fifteen amperes for upkeep of car batteries or to recharge a automobile battery that has by chance discharged. Some chargers use pulse know-how, during which a series of electrical pulses is fed to the battery. The DC pulses have a strictly controlled rise time, pulse width, pulse repetition rate and amplitude. This technology works with any dimension and sort of battery, including automotive and valve-regulated ones. The first stage is known as “bulk absorption”; the charging current shall be held excessive and fixed and is limited by the capability of the charger.