A method and a system for charging a battery in hybrid vehicles and electric vehicles are provided. An amount of energy consumption for charging a battery is calculated by taking the sum of a first amount of energy for charging a high voltage battery and a second amount of energy for use by a low voltage auxiliary system during charging. An optimal charge current for a charger is determined based on a charging option. The charging option provides a set of desired charging parameters for a charger controller. A state of charge of the battery is determined within a state of charge range. The charger controller provides a charge current to the battery. The charge current is the optimal charge current up to a maximum charge current for the state of charge range of the battery.