Dave> The WF-139 actually uses a CC algorithm.
AW = "This charger uses CC/CV charging. It charges fast on CC and slow on CV to top off."
Dave> some WF-139's trickle charge.
You can check the ending voltage yourself W.
AW = "The new WF-139 won't trickle charge after the LED turns green."
Dave> Also, as for terminating at 4.20 Volts
AW = "( newer version .. terminates at 4.2V +/- 0.05V ). I have done testing with over 50 pcs. of them and none of them charges above 4.25V."
Pila IBC Charger Compendium post #1
and
***NEW***Intelligent Charger for LiIon cells post#1
I don't know whom this guy Dave is that he can make a thousand unsubstantiated posts and not know anything. In 2010, both should do what you need and carry over into the newer high tech cells that are coming down the line.