Battery Pack State of Health Estimation via Unit Correction

The patent divides the battery pack into individual battery units and tracks SOC and aging processes for each unit separately. By segmenting the monitoring approach, the system can identify correction opportunities for each unit based on its own voltage, current, and temperature characteristics, rather than treating the entire pack as a single entity. This enables accurate SOH estimation by considering cumulative capacity changes at correction opportunities for specific units.

The patent implements a feedback mechanism by continuously monitoring voltage, current, and temperature of each battery unit during charging and discharging processes. When a correction opportunity is detected (based on consistent SOC measurements), the system uses this feedback information to calculate cumulative capacity changes and update SOH estimates. This feedback loop allows the system to adapt to inconsistent aging processes among different battery units.

The patent prepares for accurate SOH estimation by continuously monitoring and tracking voltage, current, and temperature of each battery unit during normal operation. When conditions indicate a correction opportunity (consistent SOC measurements), the system is already prepared with the necessary data to calculate cumulative capacity changes. This preliminary monitoring action ensures that when the right moment arrives, accurate SOH calculation can be performed immediately without losing monitoring opportunities.

The patent employs periodic assessment of SOC consistency among battery units to identify correction opportunities. By periodically checking whether battery units have reached states suitable for accurate SOC measurement, the system determines optimal moments for SOH calculation. This periodic action transforms continuous monitoring into discrete, accurate measurement opportunities, resolving the conflict between continuous monitoring and accurate calculation timing.