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CRYSTAL® BATTERY USER MANUAL
3.5.3 Influence of Temperature on Capacity
The discharge characteristics and temperature of
batteries are closely related. When the temperature is
low, the
discharge capacity of the battery will be reduced. For
example, when the temperature is dropped from 25°C
(77˚F) to 0°C (32˚F), the capacity of the battery will
drop to about 95% of its rated capacity.
As the ambient temperature rises, the battery capacity
will increase within a certain range, for example, the
battery capacity will rise to about 105% of the rated
capacity when the temperature rises from 25°C (77˚F)
to 40°C (104˚F), however if the temperature continues
to rise, the capacity increase will slow down, and not
increase further.
In Figure 3 you will see the effect of temperature
on the capacity of the GRGS, GRFT, and GRLS series
Crystal® batteries.
Figure 3. Crystal® relationship between discharge
capacity and temperature.
3.5.4 Discharge Voltage
The termination voltage refers to the battery voltage
dropping during discharge to the minimum
working voltage required for operation. The
termination voltage and the discharge current are
closely related. Generally, during high current
discharge, the termination voltage of the battery
should be set lower. Please refer to the batteries’ data
sheet for model-specific information on low voltage
disconnect points.
Over discharging below the termination voltage
should be avoided since the over discharging could
only gain a small amount of additional capacity, but
drastically reduce the battery’s service life.
Table 3 Termination voltage of Crystal® batteries
when discharged at different current.
120
100
80
60
40
20
-40˚C
-40˚F
-30˚C
-22˚F
-20˚C
-4˚F
-10˚C
14˚F
0˚C
32˚F
10˚C
50˚F
20˚C
68˚F
30˚C
86˚F
40˚C
104˚F
50˚C
122˚F
60˚C
140˚F
CAPACITY (%)
TEMPERATURE
DISCHARGE CURRENT (A)
0.05C or less than the discharge gap
1.9
1.85
1.8
1.75
1.7
1.6
1.5
1.3
0.05C or similar to this value
0.1C or similar to this value
DISCHARGE VOLTAGE
(V/P/CELL)
0.2C or similar to this value
0.2C - 0.5C
0.5C - 1C
1C - 3C
3C