A method and apparatus for charging a rechargeable battery comprises determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery. The battery is charged with a voltage Vhv which is higher than the Vsafe. The charging voltage is removed and open circuit voltage of the battery is measured. The charging and measuring steps are repeated when the open circuit voltage is less than Vsafe, and the charging process is terminated when the open circuit voltage is substantially equal to Vsafe.