Energy storage apparatus

Improved energy storage apparatus that is compact and less expensive is disclosed. High-voltage lines are no longer required, and heat energy can be simply dissipated from each storage module in the apparatus. A switchable inductive balancing element is electrically connected in parallel with each storage cell in each storage module, through which energy or electrical charge can be shifted among the individual storage cells in each storage module using suitably designed magnetic circuits. A power resistor and a module switch are electrically connected in parallel with the series circuit formed by the storage cells in of each storage module and the switchable inductive cell balancing elements in each module are magnetically coupled to a single switchable inductive module balancing element in the module, or each is magnetically coupled to a switchable inductive balancing element of a respective transformer.