Concorde SunXtender Manual

Document No. 6-0100 Rev. E
Page 20 of 41
For repetitive deep cycling applications (deeper than 50% DOD), chargers should have an
output current of at least 0.2C (20 Amps for a 100 Ah battery). If the output current is less than
this value, the cycle life of the battery may be negatively affected. If a charger with at least 0.2C
output is not practical, an alternative charge profile using a low rate constant current stage at
the end of the absorption stage will normally improve the cycle life. The constant current stage
should be at 0.02C (2 Amps for a 100Ah battery) for no more than one hour.
Some types of battery chargers allow the user to input the Peukert constant to obtain an
optimum charging profile. For Sun Xtender® batteries, the recommended value of the Peukert
constant is n = 1.12.
5.5 Conditioning
Conditioning should be done when the battery is showing symptoms of capacity loss or when
the float voltages of series-connected batteries show excessive variation. These conditions can
be caused by letting the battery dwell too long in a low state of charge condition, or by repetitive
undercharging.
NOTE: Some chargers use the term Equalizing Charge instead of Conditioning Charge. An
Equalizing Charge is generally applied to flooded lead acid batteries that are susceptible to acid
stratification. However, an Equalizing Charge may be used to provide a Conditioning Charge for
Sun Xtender® batteries as described below.
To apply a Conditioning Charge, first go through the normal charge cycle to bring the battery to
full charge. The Conditioning Charge should then be applied by charging for 8 hours using the
volts per cell (VPC) given in the following equation:
VPC (Conditioning) = 0.00004T
2
- 0.006T + 2.705 (where T = °C).
At 25°C, the conditioning voltage is 2.58 VPC (15.5 volts for a 12 volt battery). By using the
temperature-compensated voltage, calculated from the above equation, batteries that are not in
controlled temperature environments may be conditioned without bringing them to room
temperature. If temperature compensation is not available, it is best to bring the battery to room
temperature before applying the conditioning charge.