Within Dell Power Manager software, selecting either the Default mode of Adaptive Charge or ExpressCharge™ can recharge system battery from 0% up to 35% within 20 minutes when system is powered-off and battery temperature is between 16-45 degrees Celsius. With ExpressCharge™ mode enabled, the system battery can then continue charging up to 80% within 60 minutes. After charging has reached 80% capacity, charging speed will return to normal speed. Recommended for use with the provided Dell power adapter; not recommended with a smaller capacity power adapter. Charging time may vary +/-10% due to system tolerance.