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As charging circuits have evolved it is time to understand what
the newer excepted perimeters are for charging a lead acid battery.
http://www.chargingchargers.com/tutorials/charging.html
Three Stage Battery Charging
The BULK stage involves about 80% of the recharge, wherein the
charger current is held constant (in a constant current charger), and
voltage increases. The properly sized charger will give the battery as
much current as it will accept up to charger capacity
(25% of battery capacity in amp hours), and not raise a wet battery over 125° F, or
an AGM or GEL (valve regulated) battery over 100° F.
The ABSORPTION stage (the remaining 20%, approximately) has the
charger holding the voltage at the charger's absorption voltage
(between 14.1 VDC and 14.8 VDC, depending on charger set points)
and decreasing the current until the battery is fully charged. Some
charger manufacturers call this absorption stage an equalization
stage. We don't agree with this use of the term. If the battery
won't hold a charge, or the current does not drop after the
expected recharge time, the battery may have some permanent
sulphation.
The FLOAT stage is where the charge voltage is reduced to between
13.0 VDC and 13.8 VDC and held constant, while the current is reduced
to less than 1% of battery capacity. This mode can be used to maintain
a fully charged battery indefinitely.
Recharge time can be approximated by dividing the amp hours to be
replaced by 90% of the rated output of the charger. For example, a
100 amp hour battery with a 10 % discharge would need 10 amps
replaced. Using a 5 amp charger, we have 10 amp hours divided by
90% of 5 amps (.9x5) amps = 2.22 hour recharge time estimate.
A deeply discharged battery deviates from this formula, requiring
more time per amp to be replaced.
Recharge frequency recommendations vary from expert to expert.
It appears that depth of discharge affects battery life more than
frequency of recharge. For example, recharging when the equipment
is not going to be used for a while (meal break or whatever), may
keep the average depth of discharge above 50% for a service day.
This basically applies to battery applications where the average
depth of discharge falls below 50% in a day, and the battery can
be fully recharged once during a 24 hour period.
the newer excepted perimeters are for charging a lead acid battery.
http://www.chargingchargers.com/tutorials/charging.html
Three Stage Battery Charging
The BULK stage involves about 80% of the recharge, wherein the
charger current is held constant (in a constant current charger), and
voltage increases. The properly sized charger will give the battery as
much current as it will accept up to charger capacity
(25% of battery capacity in amp hours), and not raise a wet battery over 125° F, or
an AGM or GEL (valve regulated) battery over 100° F.
The ABSORPTION stage (the remaining 20%, approximately) has the
charger holding the voltage at the charger's absorption voltage
(between 14.1 VDC and 14.8 VDC, depending on charger set points)
and decreasing the current until the battery is fully charged. Some
charger manufacturers call this absorption stage an equalization
stage. We don't agree with this use of the term. If the battery
won't hold a charge, or the current does not drop after the
expected recharge time, the battery may have some permanent
sulphation.
The FLOAT stage is where the charge voltage is reduced to between
13.0 VDC and 13.8 VDC and held constant, while the current is reduced
to less than 1% of battery capacity. This mode can be used to maintain
a fully charged battery indefinitely.
Recharge time can be approximated by dividing the amp hours to be
replaced by 90% of the rated output of the charger. For example, a
100 amp hour battery with a 10 % discharge would need 10 amps
replaced. Using a 5 amp charger, we have 10 amp hours divided by
90% of 5 amps (.9x5) amps = 2.22 hour recharge time estimate.
A deeply discharged battery deviates from this formula, requiring
more time per amp to be replaced.
Recharge frequency recommendations vary from expert to expert.
It appears that depth of discharge affects battery life more than
frequency of recharge. For example, recharging when the equipment
is not going to be used for a while (meal break or whatever), may
keep the average depth of discharge above 50% for a service day.
This basically applies to battery applications where the average
depth of discharge falls below 50% in a day, and the battery can
be fully recharged once during a 24 hour period.
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