Disclosed are charging control methods for a rechargeable battery and portable computers. The charging control method includes acquiring a control parameter for a charge current of the rechargeable battery; modifying, based on the control parameter, the charge current from a first charge current to a second charge current less than the first charge current; and charging the rechargeable battery with the second charge current. Compared with conventional methods of charging the battery always with the maximal charge current, the present disclosure can improve the battery's lifetime.