NOVELTY - The apparatus has voltage sensing units (30) i.e. arithmetic amplifiers, for sensing voltage charged in each electric energy storage cell i.e. supercapacitor cell (10). Two sets of bypass discharge units (50, 70) are connected to each electric energy storage cell in parallel, respectively, for bypassing and discharging charged electric energy according to a control signal. A control unit (90) receives voltage information from the voltage sensing units for determining whether the bypass discharge units are controlled to equalize charged voltage values of the electric energy storage cells.    USE - Electric energy storage apparatus for use with an electric car, a hydrogen fuel cell vehicle, and a power supply such as solar energy power supply and industrial power supply i.e. uninterruptible power supply (UPS).    ADVANTAGE - The apparatus includes a voltage equalization circuit for preventing an operation from stopping malfunction of the electric energy storage cell due to voltage unbalance between unit cells of the electric energy storage cell. The bypass lines move the bypass current to one of the bypass lines according to the voltage of the electric energy storage cell, thus effectively implementing the voltage equalization at the time of high-speed charging and discharging, and increasing reliability of the electric energy storage apparatus. The apparatus rapidly moves a large amount of current through the bypass line while making the bypass resistance smaller than another bypass resistance, thus increasing voltage of the electric energy storage cell for stabilizing the voltage and improving the reliability of the electric energy storage cell.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for equalizing voltage of an electric energy storage apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a block diagram of an electric energy storage apparatus.    Supercapacitor (10)    Voltage sensing units (30)    Bypass discharge units (50, 70)    Control unit (90)