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2.6 Adaptive Battery Management
Lead-acid batteries should be charged in three stages, which are
[1]
bulk or constant-current charge,
[2]
absorption or topping
charge
and [3]
float charge.
Several hours of absorption charge are needed to fully charge the
battery and prevent early failure to sulfation¹.
The relatively high voltage during absorption does however
accelerate aging due to grid corrosion on the positive plates.
Adaptive Battery Management
limits corrosion by reducing
absorption time when possible, that is: when charging a battery
that is already (nearly) fully charged.
2.7 Storage mode: less corrosion of the positive plates
Even the lower float charge voltage that follows the absorption
period will cause grid corrosion. It is therefore essential to reduce
the charge voltage even further when the battery remains
connected to the charger during more than 48 hours.
2.8 Reconditioning
A lead-acid battery that has been insufficiently charged or has
been left discharged during days or weeks will deteriorate due to
sulfation¹. If caught in time, sulfation can sometimes be partially
reversed by charging the battery with low current up to a higher
voltage.
Remarks:
a)
Reconditioning should be applied only occasionally to flat plate VRLA
(gel and AGM) batteries because the resulting gassing will dry out the
electrolyte.
b)
Cylindrical cell VRLA batteries build more internal pressure before
gassing and will therefore lose less water when subjected to
reconditioning. Some manufacturers of cylindrical cell batteries
therefore recommend the reconditioning setting in case of cyclic
application.
c)
Reconditioning can be applied to flooded batteries to “equalise” the
cells and to prevent acid stratification.
d)
Some battery charger manufactures recommend pulse charging to
reverse sulfation. However, most battery experts agree that there is
no conclusive proof that pulse charging works any better than
constant voltage charging. This is confirmed by our own tests.
