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Note:
After a 12 to 24 hour rest period following the initial charge the voltage will drop to
approximately 13.3-13.6V. This is normal, the batteries will not require re-charging. The
same holds true when drawing down the batteries. Once the batteries hit the
determined low voltage point and the load is disconnected, the voltages will rise back
up.
Do not charge the batteries initially to just 13.0 - 13.9 volts. There is a very gradual charge voltage
versus capacity curve when charging, especially between 13.6 to 13.9V. Charging them to a value in
this range (unlike lead acid batteries) can result in a very broad difference in the actual state of charge
versus any other battery in your bank. As a result, any one battery in your bank will prematurely shut
down during charging or discharging. See the charging graph below to understand the characteristics
of the LiFePO4 charging curves.
Many automotive type battery chargers will not reach 14.1V. Please check charger specifications
when selecting your charger or you can contact your KiloVault® distributor for a list of recommended
chargers.
3.1.2.
Do Not Use DC Chargers Exceeding 150 Amps
Although a nominal charge rate of 100A is recommended on an on-going basis, you can use whatever
is available as long as it does not exceed 150A.
After the charger is removed for the initial pre-
installation charge, allow them to rest for a minimum of two hours.
Note:
After the 2-hour rest period, use a DC Voltage meter to ensure that the voltage
difference between each of the batteries is not more than 0.2 volts. Failure to take these
preliminary charging steps will result in reduced capacity, make the batteries
prematurely shutdown during charging or discharging, and could void your warranty.
If the batteries are not charged to exactly the same voltage (preferably above 14.0V), then they are
not truly all at the same state-of-charge. As a result, the BMS in one or more batteries will
protectively shutdown the battery because it has either reached its high voltage maximum ahead of
the other batteries, or prematurely reached its completely discharged voltage. This situation protects
the battery bank by placing it into an open condition.