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Charging Batteries
The batteries can be charged by using good quality AC powered battery charger or from
alternative energy sources like solar panels, wind or hydro systems.
Make sure an appropriate battery charge controller is used. It is recommended that the
batteries may be charged at 10% to 13 % of the Ampere Hour capacity (20 hour discharge
rate). Also, for complete charging (return of 100 % capacity ), it is recommended that a 3
stage charger may be used (Constant current bulk charging followed by constant voltage
boost / absorption charging followed by constant voltage float charging).
Batteries, alternators and separators on vehicles / RVs
It is recommended that for powering the inverter, one or more auxiliary deep cycle batteries
should be used that are separate from the SLI batteries. The inverter should be powered
from the deep cycle batteries. For charging the SLI and the auxiliary deep cycle batteries,
the output from the alternator should be fed to these two sets of batteries through a battery
separator of appropriate capacity. The battery separator is a device that will allow the
alternator to charge the two sets of batteries when the engine is running. The separator
will allow the inverter to be operated from the auxiliary batteries and also prevent the SLI
batteries from charging the auxiliary deep cycle batteries when the engine is not running.
Battery separators are available from auto / RV / marine parts suppliers A majority of
smaller vehicles have 40 to 105 Ampere alternator and RVs have 100 to 130 Ampere
alternator. When in use, the alternators heat up and their output current capacity can drop
by up to 25%. When heated up, their charging voltage may also not reach the desired
absorption voltage and will result in return of only about 80% of the battery capacity.
In case the current output of the standard alternator is not adequate to charge the two
sets of batteries rapidly and fully to 100% of their capacity, use heavy duty alternator that
can produce higher current and voltage required to charge multiple battery systems.
These alternators are available with auto / RV parts suppliers.
