Abstract: The present invention provides for a novel system and method of charging rechargeable batteries of all types, sizes, and voltages, including lithium-ion batteries, through the application of an oscillatory or other time-dependent voltage and/or current prior to, following, and/or simultaneously with the application of a constant voltage and/or current during the charging phase of the rechargeable battery. The novel battery charging method results in a reduction in charging time and an increase in discharge capacity and cell lifetime without adversely affecting the capacity of the battery.