Power-Sonic Sealed Lead Acid Batteries - Technical Manual - Manual (Page 11)

POWER-SONIC Rechargeable Batteries
Temperature
Actual capacity is a function of ambient temperature and rate of discharge. At 20°C (68°F) rated capacity is 100%.
The capacity increases slowly above this temperature and decreases as the temperature falls. Even at -40ºC (-40°F),
however, the Power-Sonic battery will still function at better than 30% of its rated capacity when discharged at the 20-
hour rate (0.05C). At any ambient temperature, the higher the rate of discharge, the lower the available capacity. This
relationship is shown in Figure 6.
Power-Sonic batteries may be discharged at temperatures ranging from -40°C to 60°C (-40°F to 140°F) and charged
at temperatures from -20°C to 50°C (-4°F to 122°F).
While raising ambient temperature increases capacity, it also decreases useful service life. It is estimated that battery
life is halved for each 10°C (18°F) above normal room temperature.
Performance Data
Figure : Relationship between current and discharge time
for different ambient temperatures
Figure : Effect of Temperature on Capacity
Capacity Ratio (%)
Temperature (°C)
Disc
harge Time
Discharge Current (A)