Rechargeable energy storage system isolation detection

A method for assessing loss of isolation for rechargeable energy storage systems (RESSs), comprising:

• collecting isolation resistance data with a data collection module on a controller for a plurality of RESSs operating onboard a fleet of vehicles, each RESS operating onboard a vehicle to store and supply electrical power for a traction motor, wherein the isolation resistance data is based on measuring input voltages and output voltages of battery packs of each of the plurality of RESSs;
• applying statistical methods and engineering rules with an intelligent filtering and reprocessing module on the controller configured for applying statistical methods and engineering rules to remove erroneous peaks and duplicate values from the isolation resistance data;
• generating one or more isolation rules based on the isolation resistance data with a prognostic module on the controller, the isolation rules representing thresholds for determining whether a loss of isolation has occurred;
• applying the isolation rules to the isolation resistance data to identify one or more of the RESSs having an isolation issue;
• and
• identifying an isolation issue type with an assessment module on the controller for the RESSs determined to have the isolation issue, wherein the assessment module is configured for employing a severity index and a severity assessment to determine a severity and provide an early warning to a customer of each vehicle having the loss of isolation utilizing an alert module configured for transmitting an alert to an operating system onboard each vehicle to be provided the early warning.

A system for assessing loss of isolation for rechargeable energy storage systems (RESSs), comprising:

• a data collection module on a controller configured for determining isolation resistance data for a plurality of RESSs, the RESSs configured to store and supply electrical power for a traction motor of a vehicle associated therewith, wherein the isolation resistance data is based on measuring input voltages and output voltages of battery packs of each of the plurality of RESSs;
• an intelligent filtering and reprocessing module on the controller configured for generating filtered isolation resistance data by applying statistical methods and engineering rules to remove erroneous peaks and duplicate values from the isolation resistance data;
• and
• a prognostic module on the controller and configured for:
• generating a water intrusion signature and a cell corrosion signature based on the filtered isolation resistance data, the water intrusion signature representing characteristics associated with a water intrusion type of isolation loss and the cell corrosion signature representing characteristics associated with a cell corrosion type of isolation loss;
• determining whether a loss of isolation has occurred for one or more of the RESSs based at least in part on determining whether the water intrusion and/or cell corrosion signatures match with the isolation data associated therewith;
• and
• an assessment module on the controller configured for characterizing each loss of isolation, wherein the assessment module is configured for employing a severity index and a severity assessment to determine a severity and provide an early warning to a customer of each vehicle having the loss of isolation utilizing an alert module configured for transmitting an alert to an operating system onboard each vehicle to be provided the early warning.