If you read most of the Marketing Literature out there, advanced charges will always make a major point that they Temperate Compensate the batteries. I spent a little time looking into what this really was about and found this white paper:
http://www.schneider-electric.com/.../ Temp Comp White paper.pdf
Long and short of it: For FLA batteries, use: -0.028 V per 10ºF per 2 V cell.
That is it. For every 10ºF away from the 'standard' 77ºF / 12v battery I need to add or subtract 0.168v from the target charging voltage. As temp rises, I compensate the actual voltage down. For colder, compensate up. This is applied to both the Bulk and the Float set points. So, the actual 'magic' becomes:
setPointVolts += (77-batTemp) * 0.0168 ;
I have to admit - rather anticlimactic.
Oh, during my research also picked up a warning about stopping Bulk Charging if the battery raises over 125ºF. When that happens it is best to stop, or worst case drop down to the Float voltages.
It actually took more coding for that then the All Powerful Temperature Compensation!