Patent ID: 8896272

Claim:
A method comprising: generating a current from a regulator, in a current control mode, to a terminal of a battery pack over a first time period, wherein the battery pack comprises a battery cell and an equivalent series resistance in series inside the battery pack; transitioning the regulator from the current control mode to a constant voltage mode when a voltage on the terminal of the battery pack increases to a first voltage level; and generating a constant voltage to the battery pack in the constant voltage mode over a second time period following the first time period, wherein the constant voltage is set to a second voltage level at which the battery pack is considered fully charged, wherein a difference between the first voltage level and the second voltage level corresponds to a voltage produced by said equivalent series resistance and said current at the end of said current control mode just prior to said transitioning so that the voltage on the battery cell, during current control mode, is less than a maximum battery cell voltage, and wherein the voltage on the battery cell, just prior to said transitioning, is approximately equal to the second voltage level, and wherein the first voltage level is determined dynamically based on the equivalent series resistance of the battery pack.