Systems and methods for isolation resistance monitoring in a battery bank

A battery module comprising:

• one or more battery cells;
• an isolation resistance measurement circuit coupled to the one or more battery cells;
• and
• a battery monitoring system controller coupled to the one or more battery cells and to the isolation resistance measurement circuit, the battery monitoring system controller including a processing logic circuit configured to:
• receive a time synchronization signal from a control system;
• determine, based on the time synchronization signal and a unique identifier assigned to the battery monitoring system controller, a start time for an isolation resistance measurement;
• operate the isolation resistance measurement circuit to perform an isolation resistance measurement process starting at the start time;
• report a result of the isolation resistance measurement to the control system;
• update the start time based on a cycle time that is the same for each battery monitoring system controller;
• and
• at the updated start time, repeat the acts of performing the isolation resistance measurement process, reporting the result, and updating the start time.

A method comprising:

• sending a time synchronization signal from a control system to each of a plurality of battery monitoring system controllers, wherein each battery monitoring system controller is coupled to a different one of a plurality of batteries in a battery bank and wherein each battery monitoring system controller stores a unique controller identifier;
• and
• within each battery monitoring system controller:
• determining, based on the time synchronization signal and the unique controller identifier, a start time for an isolation resistance measurement, wherein the start time determined by each battery monitoring system controller is different from the start time determined by each other battery monitoring system controller and wherein the start times determined by different battery monitoring system controllers are separated by a duration sufficient to complete the isolation resistance measurement;
• in response to the start time arriving, performing an isolation resistance measurement process;
• reporting a result of the isolation resistance measurement process to the control system;
• updating the start time based on a cycle time that is the same for each battery monitoring system controller;
• and
• in response to the updated start time arriving, repeating the acts of performing the isolation resistance measurement process, reporting the result, and updating the start time.