NOVELTY - The system (100) has an analog to digital converter (44) operably connected to sense windings (36) for measuring a charge state of particular battery cell (22), where combination of row winding (34) and articular column winding (38) are electrically connected for alternately producing magnetic states in a saturable magnetic core for sensing or balancing the charge state of the battery cell. A semiconductor is connected to the battery cell to prevent leakage of charge. A transformer (24) is electrically connected to a reference voltage supply to calibrate a detector of the charge state.    USE - Battery system for monitoring individual battery voltages during discharge i.e. battery under load, or charging and for balancing battery cells e.g. lithium-ion cells, fuel cells and electrochemical cells. Uses include but are not limited to hybrid cars, aerospace/spacecraft applications, telecommunication power supplies, computer power supplies, uninterruptible power supplies, electric utility energy storage and commercial applications.    ADVANTAGE - The system can sense voltages and/or balancing individual cells or banks of battery cells with less complex circuitry and inherent galvanic isolation while providing the ability to spot a single bad cell in a battery that comprise several hundred or more battery cells. The system allows control electronics to be programmed to perform an auto calibration at desired intervals to reduce cell voltage measurement inaccuracies. The system utilizes parallel/series arrangements of diodes to improve failure tolerance. The system allows a transistor type current source to reduce the duration of spikes due to the inductance of the transformer. The system allows a sensor to be utilized to sense the magnetic saturation by measuring the resulting increase in row or column winding current that occurs at saturation, thus accurately eliminating or reducing unnecessary pulses and control the required pulse length. The semiconductors limits leakage current drains on the cells and provides inherent limits on overcharge rates.    DETAILED DESCRIPTION - The semiconductor is a diode (32), transistor, or MOSFET. An INDEPENDENT CLAIM is also included for a method for monitoring a battery system.    DESCRIPTION OF DRAWING(S) - The drawing shows a circuit block diagram of a battery cell array layout.    Battery cell (22)    Transformer (24)    Row winding (34)    Sense windings (36)    Articular column winding (38)    Analog to digital converter (44)    Battery system (100)