A question about battery chargers

摘要

I am trying to build myself a battery charger using a PICAXE, using delta V as the detection of full charge but it constantly cuts out early; eg, after 20 seconds. I won't bore you with the code but basically it reads the voltage (using readadc10 for higher resolution) and compares it to the previous reading. If its higher, it repeats this process; if it's lower, it double checks.