GB430791A - A method of and apparatus for charging accumulator batteries in series - Google Patents

Abstract

430,791. Charging and discharging batteries. BRITANNIA BATTERIES, Ltd., Union Street, Redditch, Worcestershire.- (Accumulatoren-Fabrik Akt.-Ges.; 3, Askanischer Platz, Berlin) Oct. 25, 1934, No. 30636. [Class 38 (iv)] In a system for charging a number of batteries 61, 62, 63, in series, the occurrence of a voltage across any battery exceeding the gassing voltage, due, for example, to gassing or sulphation, causes insertion of a resistance W, W2 or W3, in shunt with that battery so as to reduce its charging current without affecting the current flowing through the other batteries. This is effected by relays sch1, sch2 and sch3 responsive to the voltages across the respective batteries and arranged to switch in the resistances W1, W2, W3. Auxiliary contacts k1, k2, k3 on these relays control the circuit of a relay sp which is de-energized and opens a circuit breaker n to disconnect the resistances from the batteries when all the batteries have reached the gassing state. Fully charged batteries may automatically be disconnected from the circuit and may be replaced by equivalent resistances or the charging voltage may be automatically reduced. In a modification two batteries are charged in series and a single resistance is controlled by a relay so as to be connected in shunt with the battery which first reaches gassing voltage and to be disconnected when both batteries have reached this state. The relay has a differential action and the energization of its two coils is controlled by further relays responsive to the voltages of the respective batteries. Further relays responsive to the state of charge of the battieies cut out a fully charged battery and replace it by a resistance. When all the batteries are cut out the supply circuit is opened.