Partial discharge fault detector for battery testing

A method of testing a battery, the method comprising:

• applying a voltage to an assembly comprising a first battery electrode, a second battery electrode and a separator layer disposed between the first and second battery electrodes, wherein the voltage is less than a threshold value of a characteristic breakdown voltage of the separator layer;
• logging measures of a current caused by partial discharges in the separator layer caused by the contaminants or voids in the separator layer, or at an interface between the first battery electrode and the separator layer, or at an interface between the second battery electrode and the separator layer, or in the separator layer;
• and
• outputting the measures of the current of the partial discharges caused by the partial discharges to determine a pass or a fail for the assembly.

A system for testing batteries, the system comprising:

• a controller comprising a processor;
• a tangible, non-transitory computer-readable medium that stores instructions, which when executed by the processor causes the processor to:
• apply a voltage from a voltage source to an assembly comprising a first battery electrode, a second battery electrode and a separator layer disposed between the first and second battery electrodes, wherein the voltage is less than a threshold value of a characteristic breakdown voltage of the separator layer;
• control a current logger connected to the second battery electrode to measure a current caused by partial discharges in the separator layer caused by the contaminants or voids in the separator layer, or at an interface between the first battery electrode and the separator layer, or at an interface between the second battery electrode and the separator layer, or in the separator layer;
• and
• determine a pass or a fail for the assembly.