|
GFX
sealed lead acid batteries is an extensive, economical and memory
free power source. In order to maximize battery service life,
it is important to select a suitable charger and to charge the battery in an upright position. Overcharge will reduce
electrolyte and cause quick damage to battery. The charging method
depends on the battery application as follows: |
|
Cyclic
operation
The range of controlled voltage is 2.4V~2.5V / per cell (6V battery
is 7.2V~7.5V, 12V battery is 14.4V~15V), limit initial current
is 0.4CA or less. The battery is fully charged as long as the
charging voltage reaches 7.5V (6V battery) or 15V (12V battery)
and charging current drops to approximately 0.01CA. After that,
the charger should either be disconnected or switched to float
voltage.
Float
or standby operations
The range of controlled voltage is 2.25V~2.3V/ per cell (6V battery
is 6.75V~6.9V, 12V battery is 13.5V~13.8V). When battery held
at above voltage, charger will fit its current level and maintain
itself in a fully charged condition.
Recharge
battery during storage
Refresh battery during long-term storage. The regulation range
of controlled voltage and current as same as cyclic operation,
also short time charge allowed if it is constant voltage charger.
Rapid
charge
When the batteries are charged rapidly, a large current is required
for supplying energy into the battery in a short time. Therefore
the charging cut-off devices are installed to avoid overcharging
and damaging the battery.
Charging
voltage relate to temperature
The charging voltage is recommended to be adjusted to compensate
for the battery temperature. That may be done by detecting of
ambient temperature near the battery instead of the battery temperature.
(a)
Cycle use
(b) Trickle use
 |
Constant
voltage charging (Fig7,8)
The constant voltage charger is the most suitable and effective
method to charge sealed lead acid batteries. Its output voltage
is preset to protect batteries without overcharging. This method
is sufficient enough for the batteries used in general application.
Fig.7
Constant voltage charger circuits 
Charging
time
Time is required to complete each charge that depend on the battery
discharging condition, characteristics of charger, or the temperature
during charge. The following shows the estimated time to charge
the battery for cyclic use.
Cyclic use
1) Discharge current more than 0.25CA
Charging time = Cdis / I + (3 ~ 5) h
2) Discharge current less than 0.25CA
Charging time = Cdis / I + (6 ~ 10) h
*Cdis: Ampere-hour discharge before charge (Ah).
* I : Initial charging current (A)
|
