Page 131 - Lindens Handbook of Batteries
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5.8 PRINCIPLES OF OPERATION
FIGURE 5.8 Battery contact designs that prevent reverse installation of cells.
Two commonly used battery circuits that are potentially dangerous without proper battery orienta-
tion are:
1. Series/parallel with one battery reversed (Fig. 5.9). In this circuit, battery 3 has been reversed. As
a result, batteries 1–3 are now in series and are charging battery 4. This condition can be avoided,
if possible, by using a single series string of larger batteries. Further, as discussed in Sec. 5.2.1, the
use of diodes in each series section will at least prevent one parallel stack from charging the other.
2. Multicell series stack with one battery reversed in position (Fig. 5.10). The fourth battery is
reversed and will be charged when the circuit is closed to operate the device. Depending on
the magnitude of the current, the battery may vent or rupture. The magnitude of the current is
dependent on the device load, the battery voltage, the condition of the reversed battery, and other
conditions of the discharge.
FIGURE 5.9 Series/parallel circuit; FIGURE 5.10 One cell reversed in a series stack;
cell 4 being charged cell 4 being charged.
