ZTS MBT-LA2 - Manual (Page 11)

temperature, and the specified cut-off voltage. Most
batteries have a rated capacity, expressed in amp-hours
(AH), that is based on a 20 hour constant discharge
to a cut-off voltage of 1.75v per cell. For example, a
6v battery with a rated capacity of 5AH should deliver
250mA for 20 hours before its voltage drops to 5.25v.
Capacity will decrease at higher rates of discharge and
increase with lower rates of discharge. A new battery
will achieve optimum capacity only after several com-
plete charge-discharge cycles, or by float charging it
for at least 30 days.
Self Discharge
Batteries that are stored at room temperature will
lose, on average, about 3% of their charge per month
through self discharge. Thus a new, fully charged bat-
tery which has been stored for a year may test 60%
until it is recharged.
Battery Life
SLA batteries will lose capacity through aging. For
example, a battery on float charge (stand-by use) will
fall to about 60% of its original rated capacity after
3-5 years of service. In cyclic use, a typical battery
will produce about 500 charge-discharge cycles before
falling to 60% of original rated capacity. Other factors
that affect capacity are the depth and rate of discharge,
ambient temperature, and charging method.
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