In one implementation, a method for charging a battery system is provided. The method includes enabling determining if a charger is coupled to a battery system, the battery system including one or more cells and a charge enable transistor. The method also includes enabling determining if a voltage level of the cells is less than a predetermined first low voltage level. If the voltage level of the cells is less than the predetermined first low voltage level, enabling charging of the cells at a reduced rate including adjusting a voltage applied to the charge transistor gate terminal to regulate a voltage seen by the charger to a level that is less than a predetermined second voltage level. Additionally, when the voltage of the cells reaches the predetermined first low voltage level, the method includes substantially fully enabling the charge transistor to allow for charging at full rate by the charger.