A circuit current balancing apparatus balances circuit currents among units of a battery device. The circuit current balancing apparatus is provided with a plurality of cell stacks respectively composed of at least one cell. The apparatus balances a circuit current of a control circuit connected to each of the plurality of cell stacks for controlling and monitoring a status of the cell stack. The apparatus also includes a comparator for calculating and outputting a voltage difference between an output voltage of the corresponding cell stack and a voltage of the control circuit connected to the corresponding cell stack, and a current source for adding or subtract a dummy current to/from a circuit current of the control circuit in correspondence with the output of the comparator.