User Manual

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Charging Efficiency
The charging efficiency ( ) of a battery is expressed by
the following formula:
(Ah) Ampere hours Discharged
=
(Ah) Ampere hours Charged
The charging efficiency varies depending upon the state
of charge of the battery, temperatures and charging rates.
Figure 30 illustrates the concept of the state of charge
and charging efficiency. As shown in Figure 31, Yuasa NP
batteries exhibit very high charging efficiency, even at
low charging rates, unlike some nickel cadmium batteries.
Cyclic Service Life
There are a number of factors that will affect the length of
cyclic service of a battery. The most significant are ambient
operating temperature, discharge rate, depth of discharge,
and the manner in which the battery is recharged.
Generally speaking, the most important factor is depth of
discharge. Figure 32 illustrates the effects of depth of
discharge on cyclic life.
EXPECTED SERVICE LIFE OF NP BATTERIES