Storage battery selection by rated voltage

Storage batteries are packaged with storage-battery elements with the number depending on required rated voltage of the entire battery. Rated voltage of one storage-battery element is equal to 1,2 V. Rated voltage of battery is calculated by formula:

Ubat = Uel×nel 

where Ubat is rated battery voltage, V,
Uel is rated element voltage, V,
nel is a number of elements in a battery, pcs.

Consequently, if, for instance, one needs storage battery with rated voltage equal to 48 V, then the required number of elements is equal to (48÷1,2) = 40 pcs.

At selection of nickel-cadmium storage battery one should take into account that recommended final voltage of element is equal to 1 V. Moreover, one should take into consideration that voltage drop across interconnecting cables and buses must not exceed 2%.