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The charger has a reactivation feature to awaken a sleeping lithium battery. The
protection circuit of lithium battery will typically turn the battery off and make it unusable if
over-discharged. This can happen when storing a lithium battery pack in a discharged
state for any length of time as self-discharge would gradually deplete the remaining
charge. Without the wake-up feature to reactivate and recharge batteries, these batteries
would become unserviceable and the packs would be discarded. The charger will apply a
small charge current to activate the protection circuit and if a correct cell voltage can be
reached, it starts a normal charge.
The charge controller has a reactivation feature to awaken a sleeping lithium battery. The
protection circuit of lithium battery will typically turn the battery off and make it unusable if
over-discharged. This can happen when storing a lithium battery pack in a discharged
state for any length of time as self-discharge would gradually deplete the remaining
charge. Without the wake-up feature to reactivate and recharge batteries, these batteries
would become unserviceable and the packs would be discarded. The charge controller
will apply a small charge current to activate the protection circuit and if a correct cell
voltage can be reached, it starts a normal charge.
Four Charging Stages
Lithium Battery Activation
Float Charge:
After the constant voltage stage, the charger will reduce the battery voltage to
a float voltage set point. Once the battery is fully charged, there will be no more chemical
reactions and all the charge current would turn into heat or gas. Because of this, the charger will
reduce the voltage charge to smaller quantity, while lightly charging the battery. The purpose for
this is to offset the power consumption while maintaining a full battery storage capacity. In the
event that a load drawn from the battery exceeds the charge current, the charger will no longer
be able to maintain the battery to a Float set point and the charger will end the float charge stage
and refer back to bulk charging.
Constant Charging:
When the battery reaches the constant voltage set point, the charger will
start to operate in constant charging mode, where it is no longer MPPT charging. The current will
drop gradually. This has two stages, equalize and boost, and they are not carried out constantly
in a full charge process to avoid too much gas precipitation or overheating of the battery.
Boost Charge:
Boost stage maintains a charge for 2 hours by default.
Equalization:
Is carried out every 28 days of the month. It is intentional overcharging of
the battery for a controlled period of time. Certain types of batteries benefit from periodic
equalizing charge, which can stir the electrolyte, balance battery voltage and complete
chemical reaction. Equalizing charge increases the battery voltage, higher than the standard
complement voltage, which gasifies the battery electrolyte.
Over-charging and excessive gas precipitation may damage the battery plates
and activate material shedding on them. Too high of equalizing charge or for
too long may cause damage. Please carefully review the specific
requirements of the battery used in the system.
WARNING
