Hey,
I recently built a QAV250 quad, and alongside with it, I got a B3AC Wolfpack charger..
The battery I have is a Wolfpack 1800mah 11.1v 25c. This takes an extremely long time to charge, and after a while, the first 2 cells will be around 4.2v and the 3rd cell is always around 3.9v and doesn't go above that no matter how long I charge.. so is there an issue with the battery? Or the charger? The charger light doesn't even go green after 6 hours of charging.. the battery voltage seems to be the same..
Should I get a better charger, like a B6AC?

I had a similar problem with my B3AC from RCBazaar. The issue was solved once I got a better charger. I had accidentally shorted the charger's balance point and that led to my charger giving up on me :p. Right now I own a fake Imax B6 from RCHyper and have had no issues yet although I don't use it much.

All the best
Nitesh.