As a new lithium ion battery, it can gain its best performance only after twice or three times 100% DOD(depth of discharge) cycles. BENZO Energy recommend to charge 4 hours in the first three cycles, and don’t charge it for over 12 hours as traditional NiMH battery and NiCd battery. Because most rechargeable lithium batteries have protection circuit PCB/BMS, when its fully charged, the PCB will stop charging to protect it, it means its no use to charge any more if its full. Begin with the fourth time, you can charge one hour more after the indication of being fully charged.