Here's a sweet little USB charger for your BT2.0 Batteries. It can charge up to 1A, and charges to 4.20v (not high voltage). It also works as a quick battery voltage checker, for SV or HV batteries :)
If youre looking to charge your BT2.0 batteries to HV, just grab some adapters here and a charger like this one.
Check out our growing BT2.0 section HERE