Product Manual

Document No. 6-0100 Rev. E
Page 21 of 41
5.6 Deep Discharge Recovery
Batteries that have been in storage for long periods of time without boost charging, or have
been kept deeply discharged for an extended time, may need to be charged at constant current
instead of constant voltage to restore capacity. The following procedure is effective if the
batteries are not too badly sulfated. WARNING: This procedure should only be done in a
well ventilated area because a significant amount of hydrogen gases may be released
from the battery.
1. Stabilize the battery at 20-30°C (68-86°F) for at least 24 hours.
2. Charge at a constant current of 5% of rated (24 hour) capacity until the voltage reaches 2.60
VPC (15.6 volts for a 12 volt battery), then continue charging at this rate for an additional 4
hours. Note that the charging voltage may get as high as 3.0 volts per cell, so the power
supply must be capable of outputting this level to maintain constant current. This constant
current charge may take 16 to 20 hours.
CAUTION: If the battery becomes hot (above 55°C/130°F) during this charge, stop the
current and allow the battery to cool to room temperature before continuing.
NOTE: The above procedure should be performed by an experienced battery maintenance
facility utilizing the proper charging and test equipment. For information regarding Concorde’s
recommended test equipment go to: www.concordebattery.com/accessories.php.
5.7 Servicing
SunXtender® AGM batteries do not need electrolyte additions as do flooded lead-acid batteries,
but periodic servicing is essential to assure continued integrity of the battery system. Servicing
should include good record keeping to document the life history of the battery system and to
identify whether corrective action needs to be taken.
The following servicing schedule is recommended:
Installation
1. Within the first week of operation, put the battery system on a full charge cycle and record
the following parameters (baseline readings):
a. Charger amperage output
b. Absorption voltage at battery system terminals
c. Float voltage at battery system terminals
d. Ripple voltage at battery system terminals (see Note 1)
e. Voltage of each battery when charger is in float mode (see Note 2)
f. Ambient temperature
2. Allow the battery system to discharge until it reaches the low voltage disconnect, and record
the following parameters:
a. Run time
b. Capacity delivered (Ampere-hours)
c. Average DC load (amperes)
d. Endpoint voltage at battery system terminals
3. After discharging, return the battery to a fully charged condition as soon as possible.