Bought a new AC Li-Ion/Poly charger for dNaNo batteries. First had to made a few mods to the charging station.
Cut away the original charging unit board:
Solder on the connecting wires and make a hole on the side of the charging station:
Here's my new AC charger which is a TLP X15. Cost is around USD60.
After charging an empty dNaNo battery here is the result:
Final Capacity: 138mah
Final Voltage: 4.21V
Charging current: 0.3A
Charging time: 33 minutes
Good thing is I no longer have to use AA batteries and I can now "top up" the batteries as the stock charging station would not allow you to charge unless the battery has less than 40% capacity.
Kev