what is the temp of the battery after a charge? if its barely warm, it may have false peaked. also, what is your mv setting? if its too low, that may cause the false peak. finally, what is your setting for the charge capacity? it should be at least 100%
you may try this:
1. fully discharge your 1500 stick pack. the cutoff should be .90v per cell or 5.4v for the whole pack. it would be better if you can borrow a discharger with at a 20amp discharge rate (the ice only goes up to 10amps)
2. after about an hour or two rest, charge the battery. the battery should be warm to the touch when it peaks. if it is barely warm and the charger stops, it false peaked.
3. after the charger stops and the pack is warm, that means it is fully charged. check the capacity in mah. if it is near 1500, that means that the pack is still good and your settings for the charger is correct. remember, you fully discharged the pack before charging so the capacity should be near the rating. also, check the peak voltage. good packs normally show about 9.1volts up to 9.5volts for a 6-cell pack.
4. if after charging, the battery is warm and the capacity only shows less than 1000mah, there may be something wrong with the battery. check the peak voltage, if it is more than 10volts, the pack may have a bad cell. i suggest getting a new 1500mah stick pack, because it may be cheaper to buy a new pack than tearing down the pack and replacing the bad cell.
hope this helps
i too have yokomo's version of the ice charger (with blue backlight and temp probe) and i highly recommend the optional temp probe so you can have another safety cutoff to avoid overcharging your batts