Caution, do not try this at home. This is against every precaution on the warning label of the battery.
This spring I found that my newest Electrifly 3s lithium-polymer would not charge. I checked with a voltmeter and found that the battery had just dropped below the voltage where my hobbico mkII would charge it.
Undeterred by the warning label, I decided to trick the charger. I assumed (apparently correctly) that the lithium-polymer mode is the only one (of three) that checks voltage. I set the battery to charge on NiMH mode and watched the voltage. I let the charger bring the battery up the less than half a volt to the proper zone, and switched over to lithium-polymer mode. I watched the balance of the cycle with no problems, and have been flying all summer on this battery.
