OPzV Battery Operation Manual
6
Fig.3-1
Available Capacity vs. Ambient Temperature
3.2 Temperature and Floating Voltage
The purpose of choosing proper floating voltage is to make the battery operate in a best
condition. If the floating voltage is higher, and then the floating current is also higher, it will
accelerate corrosion of the grid and shorten life of the battery. If the floating voltage is lower, the
battery can’t be kept in fully charged state; this will cause sulfate, decrease the capacity, and also
shorten the life of the battery.
Table 3-3 is floating voltage of VRLA battery at 25
℃
. And temperature compensation
coefficient is -3Mv/
℃
/cell
Table 3-3 Floating Voltage of VRLA Battery
（
25
℃）
Series
Floating voltage
（
V/cell
）
OPzV
2.23
±
0.02
The formula to calculate float voltage at different temperatures:
V
T
= V
25
- (T-25)×0.003
V
T
—Floating charge voltage at T temperature
V
25
—Floating charge voltage at 25
℃
,
When the float voltage is lower than 2.20V/cell or higher than 2.30V/cell after being adjusted
by temperature compensation coefficient, we suggest stopping making temperature
compensate and charge the battery with 2.20V/cell or 2.30V/cell.
3.3 Temperature and equalization charge
VRLA battery needs equalization charge periodically to guarantee normal operation. Table 3-4
is equalization voltage of VRLA battery at 25
℃
. And temperature compensation coefficient is
-5mV/
℃
/cell.
